Merge branch 'V2' into feature/V2/BulkSelectionPanel

devGuide/FILE_HISTORY_SPECIFICATION.md

@@ -0,0 +1,319 @@
+# Stirling PDF File History Specification
+
+## Overview
+
+Stirling PDF implements a client-side file history system using IndexedDB storage. File metadata, including version history and tool chains, are stored as `StirlingFileStub` objects that travel alongside the actual file data. This enables comprehensive version tracking, tool history, and file lineage management without modifying PDF content.
+
+## Storage Architecture
+
+### IndexedDB-Based Storage
+File history is stored in the browser's IndexedDB using the `fileStorage` service, providing:
+- **Persistent storage**: Survives browser sessions and page reloads
+- **Large capacity**: Supports files up to 100GB+ with full metadata
+- **Fast queries**: Optimized for file browsing and history lookups
+- **Type safety**: Structured TypeScript interfaces
+
+### Core Data Structures
+
+```typescript
+interface StirlingFileStub extends BaseFileMetadata {
+  id: FileId;                      // Unique file identifier (UUID)
+  quickKey: string;                // Deduplication key: name|size|lastModified
+  thumbnailUrl?: string;           // Generated thumbnail blob URL
+  processedFile?: ProcessedFileMetadata;  // PDF page data and processing results
+  
+  // File Metadata
+  name: string;
+  size: number;
+  type: string;
+  lastModified: number;
+  createdAt: number;
+  
+  // Version Control
+  isLeaf: boolean;                 // True if this is the latest version
+  versionNumber?: number;          // Version number (1, 2, 3, etc.)
+  originalFileId?: string;         // UUID of the root file in version chain
+  parentFileId?: string;           // UUID of immediate parent file
+  
+  // Tool History
+  toolHistory?: ToolOperation[];   // Complete sequence of applied tools
+}
+
+interface ToolOperation {
+  toolName: string;                // Tool identifier (e.g., 'compress', 'sanitize')
+  timestamp: number;               // When the tool was applied
+}
+
+interface StoredStirlingFileRecord extends StirlingFileStub {
+  data: ArrayBuffer;               // Actual file content
+  fileId: FileId;                  // Duplicate for indexing
+}
+```
+
+## Version Management System
+
+### Version Progression
+- **v1**: Original uploaded file (first version)
+- **v2**: First tool applied to original
+- **v3**: Second tool applied (inherits from v2)
+- **v4**: Third tool applied (inherits from v3)
+- **etc.**
+
+### Leaf Node System
+Only the latest version of each file family is marked as `isLeaf: true`:
+- **Leaf files**: Show in default file list, available for tool processing
+- **History files**: Hidden by default, accessible via history expansion
+
+### File Relationships
+```
+document.pdf (v1, isLeaf: false) 
+    ↓ compress
+document.pdf (v2, isLeaf: false)
+    ↓ sanitize  
+document.pdf (v3, isLeaf: true)  ← Current active version
+```
+
+## Implementation Architecture
+
+### 1. FileStorage Service (`fileStorage.ts`)
+
+**Core Methods:**
+```typescript
+// Store file with complete metadata
+async storeStirlingFile(stirlingFile: StirlingFile, stub: StirlingFileStub): Promise<void>
+
+// Load file with metadata
+async getStirlingFile(id: FileId): Promise<StirlingFile | null>
+async getStirlingFileStub(id: FileId): Promise<StirlingFileStub | null>
+
+// Query operations  
+async getLeafStirlingFileStubs(): Promise<StirlingFileStub[]>
+async getAllStirlingFileStubs(): Promise<StirlingFileStub[]>
+
+// Version management
+async markFileAsProcessed(fileId: FileId): Promise<boolean>  // Set isLeaf = false
+async markFileAsLeaf(fileId: FileId): Promise<boolean>       // Set isLeaf = true
+```
+
+### 2. File Context Integration
+
+**FileContext** manages runtime state with `StirlingFileStub[]` in memory:
+```typescript
+interface FileContextState {
+  files: {
+    ids: FileId[];
+    byId: Record<FileId, StirlingFileStub>;
+  };
+}
+```
+
+**Key Operations:**
+- `addFiles()`: Stores new files with initial metadata
+- `addStirlingFileStubs()`: Loads existing files from storage with preserved metadata
+- `consumeFiles()`: Processes files through tools, creating new versions
+
+### 3. Tool Operation Integration
+
+**Tool Processing Flow:**
+1. **Input**: User selects files (marked as `isLeaf: true`)
+2. **Processing**: Backend processes files and returns results
+3. **History Creation**: New `StirlingFileStub` created with:
+   - Incremented version number
+   - Updated tool history
+   - Parent file reference
+4. **Storage**: Both parent (marked `isLeaf: false`) and child (marked `isLeaf: true`) stored
+5. **UI Update**: FileContext updated with new file state
+
+**Child Stub Creation:**
+```typescript
+export function createChildStub(
+  parentStub: StirlingFileStub, 
+  operation: { toolName: string; timestamp: number }, 
+  resultingFile: File, 
+  thumbnail?: string
+): StirlingFileStub {
+  return {
+    id: createFileId(),
+    name: resultingFile.name,
+    size: resultingFile.size,
+    type: resultingFile.type,
+    lastModified: resultingFile.lastModified,
+    quickKey: createQuickKey(resultingFile),
+    createdAt: Date.now(),
+    isLeaf: true,
+    
+    // Version Control
+    versionNumber: (parentStub.versionNumber || 1) + 1,
+    originalFileId: parentStub.originalFileId || parentStub.id,
+    parentFileId: parentStub.id,
+    
+    // Tool History
+    toolHistory: [...(parentStub.toolHistory || []), operation],
+    thumbnailUrl: thumbnail
+  };
+}
+```
+
+## UI Integration
+
+### File Manager History Display
+
+**FileManager** (`FileManager.tsx`) provides:
+- **Default View**: Shows only leaf files (`isLeaf: true`)
+- **History Expansion**: Click to show all versions of a file family
+- **History Groups**: Nested display using `FileHistoryGroup.tsx`
+
+**FileListItem** (`FileListItem.tsx`) displays:
+- **Version Badges**: v1, v2, v3 indicators
+- **Tool Chain**: Complete processing history in tooltips
+- **History Actions**: "Show/Hide History" toggle, "Restore" for history files
+
+### FileManagerContext Integration
+
+**File Selection Flow:**
+```typescript
+// Recent files (from storage)
+onRecentFileSelect: (stirlingFileStubs: StirlingFileStub[]) => void
+// Calls: actions.addStirlingFileStubs(stirlingFileStubs, options)
+
+// New uploads  
+onFileUpload: (files: File[]) => void
+// Calls: actions.addFiles(files, options)
+```
+
+**History Management:**
+```typescript
+// Toggle history visibility
+const { expandedFileIds, onToggleExpansion } = useFileManagerContext();
+
+// Restore history file to current
+const handleAddToRecents = (file: StirlingFileStub) => {
+  fileStorage.markFileAsLeaf(file.id);  // Make this version current
+};
+```
+
+## Data Flow
+
+### New File Upload
+```
+1. User uploads files → addFiles() 
+2. Generate thumbnails and page count
+3. Create StirlingFileStub with isLeaf: true, versionNumber: 1
+4. Store both StirlingFile + StirlingFileStub in IndexedDB
+5. Dispatch to FileContext state
+```
+
+### Tool Processing
+```
+1. User selects tool + files → useToolOperation()
+2. API processes files → returns processed File objects
+3. createChildStub() for each result:
+   - Parent marked isLeaf: false
+   - Child created with isLeaf: true, incremented version
+4. Store all files with updated metadata
+5. Update FileContext with new state
+```
+
+### File Loading (Recent Files)
+```
+1. User selects from FileManager → onRecentFileSelect()
+2. addStirlingFileStubs() with preserved metadata
+3. Load actual StirlingFile data from storage  
+4. Files appear in workbench with complete history intact
+```
+
+## Performance Optimizations
+
+### Metadata Regeneration
+When loading files from storage, missing `processedFile` data is regenerated:
+```typescript
+// In addStirlingFileStubs()
+const needsProcessing = !record.processedFile || 
+                        !record.processedFile.pages || 
+                        record.processedFile.pages.length === 0;
+
+if (needsProcessing) {
+  const result = await generateThumbnailWithMetadata(stirlingFile);
+  record.processedFile = createProcessedFile(result.pageCount, result.thumbnail);
+}
+```
+
+### Memory Management
+- **Blob URL Tracking**: Automatic cleanup of thumbnail URLs
+- **Lazy Loading**: Files loaded from storage only when needed
+- **LRU Caching**: File objects cached in memory with size limits
+
+## File Deduplication
+
+### QuickKey System
+Files are deduplicated using `quickKey` format:
+```typescript
+const quickKey = `${file.name}|${file.size}|${file.lastModified}`;
+```
+
+This prevents duplicate uploads while allowing different versions of the same logical file.
+
+## Error Handling
+
+### Graceful Degradation
+- **Storage Failures**: Files continue to work without persistence
+- **Metadata Issues**: Missing metadata regenerated on demand
+- **Version Conflicts**: Automatic version number resolution
+
+### Recovery Scenarios
+- **Corrupted Storage**: Automatic cleanup and re-initialization
+- **Missing Files**: Stubs cleaned up automatically
+- **Version Mismatches**: Automatic version chain reconstruction
+
+## Developer Guidelines
+
+### Adding File History to New Components
+
+1. **Use FileContext Actions**:
+```typescript
+const { actions } = useFileActions();
+await actions.addFiles(files);  // For new uploads
+await actions.addStirlingFileStubs(stubs);  // For existing files
+```
+
+2. **Preserve Metadata When Processing**:
+```typescript
+const childStub = createChildStub(parentStub, {
+  toolName: 'compress',
+  timestamp: Date.now()
+}, processedFile, thumbnail);
+```
+
+3. **Handle Storage Operations**:
+```typescript
+await fileStorage.storeStirlingFile(stirlingFile, stirlingFileStub);
+const stub = await fileStorage.getStirlingFileStub(fileId);
+```
+
+### Testing File History
+
+1. **Upload files**: Should show v1, marked as leaf
+2. **Apply tool**: Should create v2, mark v1 as non-leaf
+3. **Check FileManager**: History should show both versions
+4. **Restore old version**: Should mark old version as leaf
+5. **Check storage**: Both versions should persist in IndexedDB
+
+## Future Enhancements
+
+### Potential Improvements
+- **Branch History**: Support for parallel processing branches
+- **History Export**: Export complete version history as JSON
+- **Conflict Resolution**: Handle concurrent modifications
+- **Cloud Sync**: Sync history across devices
+- **Compression**: Compress historical file data
+
+### API Extensions
+- **Batch Operations**: Process multiple version chains simultaneously
+- **Search Integration**: Search within tool history and file metadata
+- **Analytics**: Track usage patterns and tool effectiveness
+
+---
+
+**Last Updated**: January 2025  
+**Implementation**: Stirling PDF Frontend v2  
+**Storage Version**: IndexedDB with fileStorage service

frontend/public/locales/en-GB/translation.json

@@ -683,7 +683,116 @@
       "8": "Document #6: Page 10"
     },
     "splitPages": "Enter pages to split on:",
-    "submit": "Split"
+    "submit": "Split",
+    "steps": {
+      "chooseMethod": "Choose Method",
+      "settings": "Settings"
+    },
+    "settings": {
+      "selectMethodFirst": "Please select a split method first"
+    },
+    "error": {
+      "failed": "An error occurred while splitting the PDF."
+    },
+    "method": {
+      "label": "Choose split method",
+      "placeholder": "Select how to split the PDF"
+    },
+    "methods": {
+      "prefix": {
+        "splitAt": "Split at",
+        "splitBy": "Split by"
+      },
+      "byPages": {
+        "name": "Page Numbers",
+        "desc": "Extract specific pages (1,3,5-10)",
+        "tooltip": "Enter page numbers separated by commas or ranges with hyphens"
+      },
+      "bySections": {
+        "name": "Sections",
+        "desc": "Divide pages into grid sections",
+        "tooltip": "Split each page into horizontal and vertical sections"
+      },
+      "bySize": {
+        "name": "File Size",
+        "desc": "Limit maximum file size",
+        "tooltip": "Specify maximum file size (e.g. 10MB, 500KB)"
+      },
+      "byPageCount": {
+        "name": "Page Count",
+        "desc": "Fixed pages per file",
+        "tooltip": "Enter the number of pages for each split file"
+      },
+      "byDocCount": {
+        "name": "Document Count",
+        "desc": "Create specific number of files",
+        "tooltip": "Enter how many files you want to create"
+      },
+      "byChapters": {
+        "name": "Chapters",
+        "desc": "Split at bookmark boundaries",
+        "tooltip": "Uses PDF bookmarks to determine split points"
+      },
+      "byPageDivider": {
+        "name": "Page Divider",
+        "desc": "Auto-split with divider sheets",
+        "tooltip": "Use QR code divider sheets between documents when scanning"
+      }
+    },
+    "value": {
+      "fileSize": {
+        "label": "File Size",
+        "placeholder": "e.g. 10MB, 500KB"
+      },
+      "pageCount": {
+        "label": "Pages per File",
+        "placeholder": "e.g. 5, 10"
+      },
+      "docCount": {
+        "label": "Number of Files",
+        "placeholder": "e.g. 3, 5"
+      }
+    },
+    "tooltip": {
+      "header": {
+        "title": "Split Methods Overview"
+      },
+      "byPages": {
+        "title": "Split at Page Numbers",
+        "text": "Split your PDF at specific page numbers. Using 'n' splits after page n. Using 'n-m' splits before page n and after page m.",
+        "bullet1": "Single split points: 3,7 (splits after pages 3 and 7)",
+        "bullet2": "Range split points: 3-8 (splits before page 3 and after page 8)",
+        "bullet3": "Mixed: 2,5-10,15 (splits after page 2, before page 5, after page 10, and after page 15)"
+      },
+      "bySections": {
+        "title": "Split by Grid Sections",
+        "text": "Divide each page into a grid of sections. Useful for splitting documents with multiple columns or extracting specific areas.",
+        "bullet1": "Horizontal: Number of rows to create",
+        "bullet2": "Vertical: Number of columns to create",
+        "bullet3": "Merge: Combine all sections into one PDF"
+      },
+      "bySize": {
+        "title": "Split by File Size",
+        "text": "Create multiple PDFs that don't exceed a specified file size. Ideal for file size limitations or email attachments.",
+        "bullet1": "Use MB for larger files (e.g., 10MB)",
+        "bullet2": "Use KB for smaller files (e.g., 500KB)",
+        "bullet3": "System will split at page boundaries"
+      },
+      "byCount": {
+        "title": "Split by Count",
+        "text": "Create multiple PDFs with a specific number of pages or documents each.",
+        "bullet1": "Page Count: Fixed number of pages per file",
+        "bullet2": "Document Count: Fixed number of output files",
+        "bullet3": "Useful for batch processing workflows"
+      },
+      "byChapters": {
+        "title": "Split by Chapters",
+        "text": "Use PDF bookmarks to automatically split at chapter boundaries. Requires PDFs with bookmark structure.",
+        "bullet1": "Bookmark Level: Which level to split on (1=top level)",
+        "bullet2": "Include Metadata: Preserve document properties",
+        "bullet3": "Allow Duplicates: Handle repeated bookmark names"
+      }
+    }
   },
   "rotate": {
     "tags": "server side",
@@ -2339,6 +2448,13 @@
     "storageLow": "Storage is running low. Consider removing old files.",
     "supportMessage": "Powered by browser database storage for unlimited capacity",
     "noFileSelected": "No files selected",
+    "showHistory": "Show History",
+    "hideHistory": "Hide History",
+    "fileHistory": "File History",
+    "loadingHistory": "Loading History...",
+    "lastModified": "Last Modified",
+    "toolChain": "Tools Applied",
+    "restore": "Restore",
     "searchFiles": "Search files...",
     "recent": "Recent",
     "localFiles": "Local Files",

frontend/src/components/FileManager.tsx

@@ -1,7 +1,7 @@
 import React, { useState, useCallback, useEffect } from 'react';
 import { Modal } from '@mantine/core';
 import { Dropzone } from '@mantine/dropzone';
-import { FileMetadata } from '../types/file';
+import { StirlingFileStub } from '../types/fileContext';
 import { useFileManager } from '../hooks/useFileManager';
 import { useFilesModalContext } from '../contexts/FilesModalContext';
 import { Tool } from '../types/tool';
@@ -15,12 +15,12 @@ interface FileManagerProps {
 }
 
 const FileManager: React.FC<FileManagerProps> = ({ selectedTool }) => {
-  const { isFilesModalOpen, closeFilesModal, onFilesSelect, onStoredFilesSelect } = useFilesModalContext();
-  const [recentFiles, setRecentFiles] = useState<FileMetadata[]>([]);
+  const { isFilesModalOpen, closeFilesModal, onFileUpload, onRecentFileSelect } = useFilesModalContext();
+  const [recentFiles, setRecentFiles] = useState<StirlingFileStub[]>([]);
   const [isDragging, setIsDragging] = useState(false);
   const [isMobile, setIsMobile] = useState(false);
 
-  const { loadRecentFiles, handleRemoveFile, convertToFile } = useFileManager();
+  const { loadRecentFiles, handleRemoveFile } = useFileManager();
 
   // File management handlers
   const isFileSupported = useCallback((fileName: string) => {
@@ -34,33 +34,26 @@ const FileManager: React.FC<FileManagerProps> = ({ selectedTool }) => {
     setRecentFiles(files);
   }, [loadRecentFiles]);
 
-  const handleFilesSelected = useCallback(async (files: FileMetadata[]) => {
+  const handleRecentFilesSelected = useCallback(async (files: StirlingFileStub[]) => {
     try {
-      // Use stored files flow that preserves original IDs
-      const filesWithMetadata = await Promise.all(
-        files.map(async (metadata) => ({
-          file: await convertToFile(metadata),
-          originalId: metadata.id,
-          metadata
-        }))
-      );
-      onStoredFilesSelect(filesWithMetadata);
+      // Use StirlingFileStubs directly - preserves all metadata!
+      onRecentFileSelect(files);
     } catch (error) {
       console.error('Failed to process selected files:', error);
     }
-  }, [convertToFile, onStoredFilesSelect]);
+  }, [onRecentFileSelect]);
 
   const handleNewFileUpload = useCallback(async (files: File[]) => {
     if (files.length > 0) {
       try {
         // Files will get IDs assigned through onFilesSelect -> FileContext addFiles
-        onFilesSelect(files);
+        onFileUpload(files);
         await refreshRecentFiles();
       } catch (error) {
         console.error('Failed to process dropped files:', error);
       }
     }
-  }, [onFilesSelect, refreshRecentFiles]);
+  }, [onFileUpload, refreshRecentFiles]);
 
   const handleRemoveFileByIndex = useCallback(async (index: number) => {
     await handleRemoveFile(index, recentFiles, setRecentFiles);
@@ -85,7 +78,7 @@ const FileManager: React.FC<FileManagerProps> = ({ selectedTool }) => {
   // Cleanup any blob URLs when component unmounts
   useEffect(() => {
     return () => {
-      // FileMetadata doesn't have blob URLs, so no cleanup needed
+      // StoredFileMetadata doesn't have blob URLs, so no cleanup needed
       // Blob URLs are managed by FileContext and tool operations
       console.log('FileManager unmounting - FileContext handles blob URL cleanup');
     };
@@ -146,7 +139,7 @@ const FileManager: React.FC<FileManagerProps> = ({ selectedTool }) => {
         >
           <FileManagerProvider
             recentFiles={recentFiles}
-            onFilesSelected={handleFilesSelected}
+            onRecentFilesSelected={handleRecentFilesSelected}
             onNewFilesSelect={handleNewFileUpload}
             onClose={closeFilesModal}
             isFileSupported={isFileSupported}

frontend/src/components/fileEditor/FileEditor.tsx

@@ -78,22 +78,6 @@ const FileEditor = ({
   // Use activeStirlingFileStubs directly - no conversion needed
   const localSelectedIds = contextSelectedIds;
 
-  // Helper to convert StirlingFileStub to FileThumbnail format
-  const recordToFileItem = useCallback((record: any) => {
-    const file = selectors.getFile(record.id);
-    if (!file) return null;
-
-    return {
-      id: record.id,
-      name: file.name,
-      pageCount: record.processedFile?.totalPages || 1,
-      thumbnail: record.thumbnailUrl || '',
-      size: file.size,
-      file: file
-    };
-  }, [selectors]);
-
-
   // Process uploaded files using context
   const handleFileUpload = useCallback(async (uploadedFiles: File[]) => {
     setError(null);
@@ -404,13 +388,10 @@ const FileEditor = ({
             }}
           >
             {activeStirlingFileStubs.map((record, index) => {
-              const fileItem = recordToFileItem(record);
-              if (!fileItem) return null;
-
               return (
                 <FileEditorThumbnail
                   key={record.id}
-                  file={fileItem}
+                  file={record}
                   index={index}
                   totalFiles={activeStirlingFileStubs.length}
                   selectedFiles={localSelectedIds}
@@ -421,7 +402,7 @@ const FileEditor = ({
                   onSetStatus={setStatus}
                   onReorderFiles={handleReorderFiles}
                   toolMode={toolMode}
-                  isSupported={isFileSupported(fileItem.name)}
+                  isSupported={isFileSupported(record.name)}
                 />
               );
             })}

frontend/src/components/fileEditor/FileEditorThumbnail.tsx

@@ -8,22 +8,17 @@ import PushPinIcon from '@mui/icons-material/PushPin';
 import PushPinOutlinedIcon from '@mui/icons-material/PushPinOutlined';
 import DragIndicatorIcon from '@mui/icons-material/DragIndicator';
 import { draggable, dropTargetForElements } from '@atlaskit/pragmatic-drag-and-drop/element/adapter';
+import { StirlingFileStub } from '../../types/fileContext';
 
 import styles from './FileEditor.module.css';
 import { useFileContext } from '../../contexts/FileContext';
 import { FileId } from '../../types/file';
+import ToolChain from '../shared/ToolChain';
+
 
-interface FileItem {
-  id: FileId;
-  name: string;
-  pageCount: number;
-  thumbnail: string | null;
-  size: number;
-  modifiedAt?: number | string | Date;
-}
 
 interface FileEditorThumbnailProps {
-  file: FileItem;
+  file: StirlingFileStub;
   index: number;
   totalFiles: number;
   selectedFiles: FileId[];
@@ -64,6 +59,8 @@ const FileEditorThumbnail = ({
   }, [activeFiles, file.id]);
   const isPinned = actualFile ? isFilePinned(actualFile) : false;
 
+  const pageCount = file.processedFile?.totalPages || 0;
+
   const downloadSelectedFile = useCallback(() => {
     // Prefer parent-provided handler if available
     if (typeof onDownloadFile === 'function') {
@@ -109,22 +106,21 @@ const FileEditorThumbnail = ({
 
   const pageLabel = useMemo(
     () =>
-      file.pageCount > 0
-        ? `${file.pageCount} ${file.pageCount === 1 ? 'Page' : 'Pages'}`
+      pageCount > 0
+        ? `${pageCount} ${pageCount === 1 ? 'Page' : 'Pages'}`
         : '',
-    [file.pageCount]
+    [pageCount]
   );
 
   const dateLabel = useMemo(() => {
-    const d =
-      file.modifiedAt != null ? new Date(file.modifiedAt) : new Date(); // fallback
+    const d = new Date(file.lastModified);
     if (Number.isNaN(d.getTime())) return '';
     return new Intl.DateTimeFormat(undefined, {
       month: 'short',
       day: '2-digit',
       year: 'numeric',
     }).format(d);
-  }, [file.modifiedAt]);
+  }, [file.lastModified]);
 
   // ---- Drag & drop wiring ----
   const fileElementRef = useCallback((element: HTMLDivElement | null) => {
@@ -350,7 +346,8 @@ const FileEditorThumbnail = ({
           lineClamp={3}
           title={`${extUpper || 'FILE'} • ${prettySize}`}
         >
-          {/* e.g., Jan 29, 2025 - PDF file - 3 Pages */}
+          {/* e.g.,  v2 - Jan 29, 2025 - PDF file - 3 Pages */}
+          {`v${file.versionNumber} - `}
           {dateLabel}
           {extUpper ? ` - ${extUpper} file` : ''}
           {pageLabel ? ` - ${pageLabel}` : ''}
@@ -360,9 +357,9 @@ const FileEditorThumbnail = ({
       {/* Preview area */}
       <div className={`${styles.previewBox} mx-6 mb-4 relative flex-1`}>
         <div className={styles.previewPaper}>
-          {file.thumbnail && (
+          {file.thumbnailUrl && (
             <img
-              src={file.thumbnail}
+              src={file.thumbnailUrl}
               alt={file.name}
               draggable={false}
               loading="lazy"
@@ -399,6 +396,29 @@ const FileEditorThumbnail = ({
         <span ref={handleRef} className={styles.dragHandle} aria-hidden>
           <DragIndicatorIcon fontSize="small" />
         </span>
+
+        {/* Tool chain display at bottom */}
+        {file.toolHistory && (
+          <div style={{
+            position: 'absolute',
+            bottom: '4px',
+            left: '4px',
+            right: '4px',
+            padding: '4px 6px',
+            textAlign: 'center',
+            fontWeight: 600,
+            overflow: 'hidden',
+            whiteSpace: 'nowrap'
+          }}>
+            <ToolChain
+              toolChain={file.toolHistory}
+              displayStyle="text"
+              size="xs"
+              maxWidth={'100%'}
+              color='var(--mantine-color-gray-7)'
+            />
+          </div>
+        )}
       </div>
     </div>
   );

frontend/src/components/fileManager/CompactFileDetails.tsx

@@ -5,12 +5,12 @@ import ChevronLeftIcon from '@mui/icons-material/ChevronLeft';
 import ChevronRightIcon from '@mui/icons-material/ChevronRight';
 import { useTranslation } from 'react-i18next';
 import { getFileSize } from '../../utils/fileUtils';
-import { FileMetadata } from '../../types/file';
+import { StirlingFileStub } from '../../types/fileContext';
 
 interface CompactFileDetailsProps {
-  currentFile: FileMetadata | null;
+  currentFile: StirlingFileStub | null;
   thumbnail: string | null;
-  selectedFiles: FileMetadata[];
+  selectedFiles: StirlingFileStub[];
   currentFileIndex: number;
   numberOfFiles: number;
   isAnimating: boolean;
@@ -72,12 +72,19 @@ const CompactFileDetails: React.FC<CompactFileDetailsProps> = ({
           <Text size="xs" c="dimmed">
             {currentFile ? getFileSize(currentFile) : ''}
             {selectedFiles.length > 1 && ` • ${selectedFiles.length} files`}
+            {currentFile && ` • v${currentFile.versionNumber || 1}`}
           </Text>
           {hasMultipleFiles && (
             <Text size="xs" c="blue">
               {currentFileIndex + 1} of {selectedFiles.length}
             </Text>
           )}
+          {/* Compact tool chain for mobile */}
+          {currentFile?.toolHistory && currentFile.toolHistory.length > 0 && (
+            <Text size="xs" c="dimmed">
+              {currentFile.toolHistory.map((tool: any) => tool.toolName).join(' → ')}
+            </Text>
+          )}
         </Box>
         
         {/* Navigation arrows for multiple files */}

frontend/src/components/fileManager/FileHistoryGroup.tsx

@@ -0,0 +1,68 @@
+import React from 'react';
+import { Box, Text, Collapse, Group } from '@mantine/core';
+import { useTranslation } from 'react-i18next';
+import { StirlingFileStub } from '../../types/fileContext';
+import FileListItem from './FileListItem';
+
+interface FileHistoryGroupProps {
+  leafFile: StirlingFileStub;
+  historyFiles: StirlingFileStub[];
+  isExpanded: boolean;
+  onDownloadSingle: (file: StirlingFileStub) => void;
+  onFileDoubleClick: (file: StirlingFileStub) => void;
+  onHistoryFileRemove: (file: StirlingFileStub) => void;
+  isFileSupported: (fileName: string) => boolean;
+}
+
+const FileHistoryGroup: React.FC<FileHistoryGroupProps> = ({
+  leafFile,
+  historyFiles,
+  isExpanded,
+  onDownloadSingle,
+  onFileDoubleClick,
+  onHistoryFileRemove,
+  isFileSupported,
+}) => {
+  const { t } = useTranslation();
+
+  // Sort history files by version number (oldest first, excluding the current leaf file)
+  const sortedHistory = historyFiles
+    .filter(file => file.id !== leafFile.id) // Exclude the leaf file itself
+    .sort((a, b) => (b.versionNumber || 1) - (a.versionNumber || 1));
+
+  if (!isExpanded || sortedHistory.length === 0) {
+    return null;
+  }
+
+  return (
+    <Collapse in={isExpanded}>
+      <Box ml="md" mt="xs" mb="sm">
+        <Group align="center" mb="sm">
+          <Text size="xs" fw={600} c="dimmed">
+            {t('fileManager.fileHistory', 'File History')} ({sortedHistory.length})
+          </Text>
+        </Group>
+
+        <Box ml="md">
+          {sortedHistory.map((historyFile, _index) => (
+            <FileListItem
+              key={`history-${historyFile.id}-${historyFile.versionNumber || 1}`}
+              file={historyFile}
+              isSelected={false} // History files are not selectable
+              isSupported={isFileSupported(historyFile.name)}
+              onSelect={() => {}} // No selection for history files
+              onRemove={() => onHistoryFileRemove(historyFile)} // Remove specific history file
+              onDownload={() => onDownloadSingle(historyFile)}
+              onDoubleClick={() => onFileDoubleClick(historyFile)}
+              isHistoryFile={true} // This enables "Add to Recents" in menu
+              isLatestVersion={false} // History files are never latest
+              // onAddToRecents is accessed from context by FileListItem
+            />
+          ))}
+        </Box>
+      </Box>
+    </Collapse>
+  );
+};
+
+export default FileHistoryGroup;

frontend/src/components/fileManager/FileInfoCard.tsx

@@ -2,10 +2,11 @@ import React from 'react';
 import { Stack, Card, Box, Text, Badge, Group, Divider, ScrollArea } from '@mantine/core';
 import { useTranslation } from 'react-i18next';
 import { detectFileExtension, getFileSize } from '../../utils/fileUtils';
-import { FileMetadata } from '../../types/file';
+import { StirlingFileStub } from '../../types/fileContext';
+import ToolChain from '../shared/ToolChain';
 
 interface FileInfoCardProps {
-  currentFile: FileMetadata | null;
+  currentFile: StirlingFileStub | null;
   modalHeight: string;
 }
 
@@ -53,11 +54,36 @@ const FileInfoCard: React.FC<FileInfoCardProps> = ({
           <Divider />
 
           <Group justify="space-between" py="xs">
-            <Text size="sm" c="dimmed">{t('fileManager.fileVersion', 'Version')}</Text>
+            <Text size="sm" c="dimmed">{t('fileManager.lastModified', 'Last Modified')}</Text>
             <Text size="sm" fw={500}>
-              {currentFile ? '1.0' : ''}
+              {currentFile ? new Date(currentFile.lastModified).toLocaleDateString() : ''}
             </Text>
           </Group>
+          <Divider />
+
+          <Group justify="space-between" py="xs">
+            <Text size="sm" c="dimmed">{t('fileManager.fileVersion', 'Version')}</Text>
+            {currentFile &&
+              <Badge size="sm" variant="light" color={currentFile?.versionNumber ? 'blue' : 'gray'}>
+                v{currentFile ? (currentFile.versionNumber || 1) : ''}
+              </Badge>}
+
+          </Group>
+
+          {/* Tool Chain Display */}
+          {currentFile?.toolHistory && currentFile.toolHistory.length > 0 && (
+            <>
+              <Divider />
+              <Box py="xs">
+                <Text size="xs" c="dimmed" mb="xs">{t('fileManager.toolChain', 'Tools Applied')}</Text>
+                <ToolChain
+                  toolChain={currentFile.toolHistory}
+                  displayStyle="badges"
+                  size="xs"
+                />
+              </Box>
+            </>
+          )}
         </Stack>
       </ScrollArea>
     </Card>

frontend/src/components/fileManager/FileListArea.tsx

@@ -4,6 +4,7 @@ import CloudIcon from '@mui/icons-material/Cloud';
 import HistoryIcon from '@mui/icons-material/History';
 import { useTranslation } from 'react-i18next';
 import FileListItem from './FileListItem';
+import FileHistoryGroup from './FileHistoryGroup';
 import { useFileManagerContext } from '../../contexts/FileManagerContext';
 
 interface FileListAreaProps {
@@ -20,8 +21,11 @@ const FileListArea: React.FC<FileListAreaProps> = ({
     recentFiles,
     filteredFiles,
     selectedFilesSet,
+    expandedFileIds,
+    loadedHistoryFiles,
     onFileSelect,
     onFileRemove,
+    onHistoryFileRemove,
     onFileDoubleClick,
     onDownloadSingle,
     isFileSupported,
@@ -50,18 +54,37 @@ const FileListArea: React.FC<FileListAreaProps> = ({
               </Stack>
             </Center>
           ) : (
-            filteredFiles.map((file, index) => (
-              <FileListItem
-                key={file.id}
-                file={file}
-                isSelected={selectedFilesSet.has(file.id)}
-                isSupported={isFileSupported(file.name)}
-                onSelect={(shiftKey) => onFileSelect(file, index, shiftKey)}
-                onRemove={() => onFileRemove(index)}
-                onDownload={() => onDownloadSingle(file)}
-                onDoubleClick={() => onFileDoubleClick(file)}
-              />
-            ))
+            filteredFiles.map((file, index) => {
+              // All files in filteredFiles are now leaf files only
+              const historyFiles = loadedHistoryFiles.get(file.id) || [];
+              const isExpanded = expandedFileIds.has(file.id);
+
+              return (
+                <React.Fragment key={file.id}>
+                  <FileListItem
+                    file={file}
+                    isSelected={selectedFilesSet.has(file.id)}
+                    isSupported={isFileSupported(file.name)}
+                    onSelect={(shiftKey) => onFileSelect(file, index, shiftKey)}
+                    onRemove={() => onFileRemove(index)}
+                    onDownload={() => onDownloadSingle(file)}
+                    onDoubleClick={() => onFileDoubleClick(file)}
+                    isHistoryFile={false} // All files here are leaf files
+                    isLatestVersion={true} // All files here are the latest versions
+                  />
+
+                  <FileHistoryGroup
+                    leafFile={file}
+                    historyFiles={historyFiles}
+                    isExpanded={isExpanded}
+                    onDownloadSingle={onDownloadSingle}
+                    onFileDoubleClick={onFileDoubleClick}
+                    onHistoryFileRemove={onHistoryFileRemove}
+                    isFileSupported={isFileSupported}
+                  />
+                </React.Fragment>
+              );
+            })
           )}
         </Stack>
       </ScrollArea>

frontend/src/components/fileManager/FileListItem.tsx

@@ -3,12 +3,16 @@ import { Group, Box, Text, ActionIcon, Checkbox, Divider, Menu, Badge } from '@m
 import MoreVertIcon from '@mui/icons-material/MoreVert';
 import DeleteIcon from '@mui/icons-material/Delete';
 import DownloadIcon from '@mui/icons-material/Download';
+import HistoryIcon from '@mui/icons-material/History';
+import RestoreIcon from '@mui/icons-material/Restore';
 import { useTranslation } from 'react-i18next';
 import { getFileSize, getFileDate } from '../../utils/fileUtils';
-import { FileMetadata } from '../../types/file';
+import { FileId, StirlingFileStub } from '../../types/fileContext';
+import { useFileManagerContext } from '../../contexts/FileManagerContext';
+import ToolChain from '../shared/ToolChain';
 
 interface FileListItemProps {
-  file: FileMetadata;
+  file: StirlingFileStub;
   isSelected: boolean;
   isSupported: boolean;
   onSelect: (shiftKey?: boolean) => void;
@@ -16,6 +20,8 @@ interface FileListItemProps {
   onDownload?: () => void;
   onDoubleClick?: () => void;
   isLast?: boolean;
+  isHistoryFile?: boolean; // Whether this is a history file (indented)
+  isLatestVersion?: boolean; // Whether this is the latest version (shows chevron)
 }
 
 const FileListItem: React.FC<FileListItemProps> = ({
@@ -25,60 +31,89 @@ const FileListItem: React.FC<FileListItemProps> = ({
   onSelect,
   onRemove,
   onDownload,
-  onDoubleClick
+  onDoubleClick,
+  isHistoryFile = false,
+  isLatestVersion = false
 }) => {
   const [isHovered, setIsHovered] = useState(false);
   const [isMenuOpen, setIsMenuOpen] = useState(false);
   const { t } = useTranslation();
+  const {expandedFileIds, onToggleExpansion, onAddToRecents } = useFileManagerContext();
 
   // Keep item in hovered state if menu is open
   const shouldShowHovered = isHovered || isMenuOpen;
 
+  // Get version information for this file
+  const leafFileId = (isLatestVersion ? file.id : (file.originalFileId || file.id)) as FileId;
+  const hasVersionHistory = (file.versionNumber || 1) > 1; // Show history for any processed file (v2+)
+  const currentVersion = file.versionNumber || 1; // Display original files as v1
+  const isExpanded = expandedFileIds.has(leafFileId);
+
   return (
     <>
       <Box
         p="sm"
         style={{
-          cursor: 'pointer',
-          backgroundColor: isSelected ? 'var(--mantine-color-gray-1)' : (shouldShowHovered ? 'var(--mantine-color-gray-1)' : 'var(--bg-file-list)'),
+          cursor: isHistoryFile ? 'default' : 'pointer',
+          backgroundColor:  isSelected
+              ? 'var(--mantine-color-gray-1)'
+              : (shouldShowHovered ? 'var(--mantine-color-gray-1)' : 'var(--bg-file-list)'),
           opacity: isSupported ? 1 : 0.5,
           transition: 'background-color 0.15s ease',
           userSelect: 'none',
           WebkitUserSelect: 'none',
           MozUserSelect: 'none',
-          msUserSelect: 'none'
+          msUserSelect: 'none',
+          paddingLeft: isHistoryFile ? '2rem' : '0.75rem', // Indent history files
+          borderLeft: isHistoryFile ? '3px solid var(--mantine-color-blue-4)' : 'none' // Visual indicator for history
         }}
-        onClick={(e) => onSelect(e.shiftKey)}
+        onClick={isHistoryFile ? undefined : (e) => onSelect(e.shiftKey)}
         onDoubleClick={onDoubleClick}
         onMouseEnter={() => setIsHovered(true)}
         onMouseLeave={() => setIsHovered(false)}
       >
         <Group gap="sm">
-          <Box>
-            <Checkbox
-              checked={isSelected}
-              onChange={() => {}} // Handled by parent onClick
-              size="sm"
-              pl="sm"
-              pr="xs"
-              styles={{
-                input: {
-                  cursor: 'pointer'
-                }
-              }}
-            />
-          </Box>
+          {!isHistoryFile && (
+            <Box>
+              {/* Checkbox for regular files only */}
+              <Checkbox
+                checked={isSelected}
+                onChange={() => {}} // Handled by parent onClick
+                size="sm"
+                pl="sm"
+                pr="xs"
+                styles={{
+                  input: {
+                    cursor: 'pointer'
+                  }
+                }}
+              />
+            </Box>
+          )}
 
           <Box style={{ flex: 1, minWidth: 0 }}>
             <Group gap="xs" align="center">
               <Text size="sm" fw={500} truncate style={{ flex: 1 }}>{file.name}</Text>
-              {file.isDraft && (
-                <Badge size="xs" variant="light" color="orange">
-                  DRAFT
-                </Badge>
+              <Badge size="xs" variant="light" color={"blue"}>
+                v{currentVersion}
+              </Badge>
+
+            </Group>
+            <Group gap="xs" align="center">
+              <Text size="xs" c="dimmed">
+                {getFileSize(file)} • {getFileDate(file)}
+              </Text>
+
+              {/* Tool chain for processed files */}
+              {file.toolHistory && file.toolHistory.length > 0 && (
+                <ToolChain
+                  toolChain={file.toolHistory}
+                  maxWidth={'150px'}
+                  displayStyle="text"
+                  size="xs"
+                />
               )}
             </Group>
-            <Text size="xs" c="dimmed">{getFileSize(file)} • {getFileDate(file)}</Text>
           </Box>
 
           {/* Three dots menu - fades in/out on hover */}
@@ -117,6 +152,46 @@ const FileListItem: React.FC<FileListItemProps> = ({
                   {t('fileManager.download', 'Download')}
                 </Menu.Item>
               )}
+
+              {/* Show/Hide History option for latest version files */}
+              {isLatestVersion && hasVersionHistory && (
+                <>
+                  <Menu.Item
+                    leftSection={
+                        <HistoryIcon style={{ fontSize: 16 }} />
+                    }
+                    onClick={(e) => {
+                      e.stopPropagation();
+                      onToggleExpansion(leafFileId);
+                    }}
+                  >
+                    {
+                      (isExpanded ?
+                        t('fileManager.hideHistory', 'Hide History') :
+                        t('fileManager.showHistory', 'Show History')
+                      )
+                    }
+                  </Menu.Item>
+                  <Menu.Divider />
+                </>
+              )}
+
+              {/* Restore option for history files */}
+              {isHistoryFile && (
+                <>
+                  <Menu.Item
+                    leftSection={<RestoreIcon style={{ fontSize: 16 }} />}
+                    onClick={(e) => {
+                      e.stopPropagation();
+                      onAddToRecents(file);
+                    }}
+                  >
+                    {t('fileManager.restore', 'Restore')}
+                  </Menu.Item>
+                  <Menu.Divider />
+                </>
+              )}
+
               <Menu.Item
                 leftSection={<DeleteIcon style={{ fontSize: 16 }} />}
                 onClick={(e) => {

frontend/src/components/layout/Workbench.tsx

@@ -42,7 +42,7 @@ export default function Workbench() {
   // Get tool registry to look up selected tool
   const { toolRegistry } = useToolManagement();
   const selectedTool = selectedToolId ? toolRegistry[selectedToolId] : null;
-  const { addToActiveFiles } = useFileHandler();
+  const { addFiles } = useFileHandler();
 
   const handlePreviewClose = () => {
     setPreviewFile(null);
@@ -81,7 +81,7 @@ export default function Workbench() {
                 setCurrentView("pageEditor");
               },
               onMergeFiles: (filesToMerge) => {
-                filesToMerge.forEach(addToActiveFiles);
+                addFiles(filesToMerge);
                 setCurrentView("viewer");
               }
             })}

frontend/src/components/shared/CardSelector.tsx

@@ -0,0 +1,99 @@
+import { Stack, Card, Text, Flex } from '@mantine/core';
+import { Tooltip } from './Tooltip';
+import { useTranslation } from 'react-i18next';
+
+export interface CardOption<T = string> {
+  value: T;
+  prefixKey: string;
+  nameKey: string;
+  tooltipKey?: string;
+  tooltipContent?: any[];
+}
+
+export interface CardSelectorProps<T, K extends CardOption<T>> {
+  options: K[];
+  onSelect: (value: T) => void;
+  disabled?: boolean;
+  getTooltipContent?: (option: K) => any[];
+}
+
+const CardSelector = <T, K extends CardOption<T>>({
+  options,
+  onSelect,
+  disabled = false,
+  getTooltipContent
+}: CardSelectorProps<T, K>) => {
+  const { t } = useTranslation();
+
+  const handleOptionClick = (value: T) => {
+    if (!disabled) {
+      onSelect(value);
+    }
+  };
+
+  const getTooltips = (option: K) => {
+    if (getTooltipContent) {
+      return getTooltipContent(option);
+    }
+    return [];
+  };
+
+  return (
+    <Stack gap="sm">
+      {options.map((option) => (
+        <Tooltip
+          key={option.value as string}
+          sidebarTooltip
+          tips={getTooltips(option)}
+        >
+          <Card
+            radius="md"
+            w="100%"
+            h={'2.8rem'}
+            style={{
+              cursor: disabled ? 'default' : 'pointer',
+              backgroundColor: 'var(--mantine-color-gray-2)',
+              borderColor: 'var(--mantine-color-gray-3)',
+              opacity: disabled ? 0.6 : 1,
+              display: 'flex',
+              flexDirection: 'row',
+              transition: 'all 0.2s ease',
+            }}
+            onMouseEnter={(e) => {
+              if (!disabled) {
+                e.currentTarget.style.backgroundColor = 'var(--mantine-color-gray-3)';
+                e.currentTarget.style.transform = 'translateY(-1px)';
+                e.currentTarget.style.boxShadow = '0 4px 8px rgba(0, 0, 0, 0.1)';
+              }
+            }}
+            onMouseLeave={(e) => {
+              if (!disabled) {
+                e.currentTarget.style.backgroundColor = 'var(--mantine-color-gray-2)';
+                e.currentTarget.style.transform = 'translateY(0px)';
+                e.currentTarget.style.boxShadow = 'none';
+              }
+            }}
+            onClick={() => handleOptionClick(option.value)}
+          >
+            <Flex align={'center'} pl="sm" w="100%">
+              <Text size="sm" c="dimmed" ta="center" fw={350}>
+                {t(option.prefixKey, "Prefix")}
+              </Text>
+              <Text
+                fw={600}
+                size="sm"
+                c={undefined}
+                ta="center"
+                style={{ marginLeft: '0.25rem' }}
+              >
+                {t(option.nameKey, "Option Name")}
+              </Text>
+            </Flex>
+          </Card>
+        </Tooltip>
+      ))}
+    </Stack>
+  );
+};
+
+export default CardSelector;

frontend/src/components/shared/FileCard.tsx

@@ -12,7 +12,7 @@ import { useIndexedDBThumbnail } from "../../hooks/useIndexedDBThumbnail";
 
 interface FileCardProps {
   file: File;
-  record?: StirlingFileStub;
+  fileStub?: StirlingFileStub;
   onRemove: () => void;
   onDoubleClick?: () => void;
   onView?: () => void;
@@ -22,12 +22,11 @@ interface FileCardProps {
   isSupported?: boolean; // Whether the file format is supported by the current tool
 }
 
-const FileCard = ({ file, record, onRemove, onDoubleClick, onView, onEdit, isSelected, onSelect, isSupported = true }: FileCardProps) => {
+const FileCard = ({ file, fileStub, onRemove, onDoubleClick, onView, onEdit, isSelected, onSelect, isSupported = true }: FileCardProps) => {
   const { t } = useTranslation();
   // Use record thumbnail if available, otherwise fall back to IndexedDB lookup
-  const fileMetadata = record ? { id: record.id, name: record.name, type: record.type, size: record.size, lastModified: record.lastModified } : null;
-  const { thumbnail: indexedDBThumb, isGenerating } = useIndexedDBThumbnail(fileMetadata);
-  const thumb = record?.thumbnailUrl || indexedDBThumb;
+  const { thumbnail: indexedDBThumb, isGenerating } = useIndexedDBThumbnail(fileStub);
+  const thumb = fileStub?.thumbnailUrl || indexedDBThumb;
   const [isHovered, setIsHovered] = useState(false);
 
   return (
@@ -177,7 +176,7 @@ const FileCard = ({ file, record, onRemove, onDoubleClick, onView, onEdit, isSel
           <Badge color="blue" variant="light" size="sm">
             {getFileDate(file)}
           </Badge>
-          {record?.id && (
+          {fileStub?.id && (
             <Badge
               color="green"
               variant="light"

frontend/src/components/shared/FileGrid.tsx

@@ -139,7 +139,7 @@ const FileGrid = ({
             <FileCard
               key={fileId + idx}
               file={item.file}
-              record={item.record}
+              fileStub={item.record}
               onRemove={onRemove ? () => onRemove(originalIdx) : () => {}}
               onDoubleClick={onDoubleClick && supported ? () => onDoubleClick(item) : undefined}
               onView={onView && supported ? () => onView(item) : undefined}

frontend/src/components/shared/FilePreview.tsx

@@ -1,7 +1,7 @@
 import React from 'react';
 import { Box, Center } from '@mantine/core';
 import InsertDriveFileIcon from '@mui/icons-material/InsertDriveFile';
-import { FileMetadata } from '../../types/file';
+import { StirlingFileStub } from '../../types/fileContext';
 import DocumentThumbnail from './filePreview/DocumentThumbnail';
 import DocumentStack from './filePreview/DocumentStack';
 import HoverOverlay from './filePreview/HoverOverlay';
@@ -9,7 +9,7 @@ import NavigationArrows from './filePreview/NavigationArrows';
 
 export interface FilePreviewProps {
   // Core file data
-  file: File | FileMetadata | null;
+  file: File | StirlingFileStub | null;
   thumbnail?: string | null;
   
   // Optional features
@@ -22,7 +22,7 @@ export interface FilePreviewProps {
   isAnimating?: boolean;
   
   // Event handlers
-  onFileClick?: (file: File | FileMetadata | null) => void;
+  onFileClick?: (file: File | StirlingFileStub | null) => void;
   onPrevious?: () => void;
   onNext?: () => void;
 }

frontend/src/components/shared/LandingPage.tsx

@@ -7,7 +7,7 @@ import { useFileHandler } from '../../hooks/useFileHandler';
 import { useFilesModalContext } from '../../contexts/FilesModalContext';
 
 const LandingPage = () => {
-  const { addMultipleFiles } = useFileHandler();
+  const { addFiles } = useFileHandler();
   const fileInputRef = React.useRef<HTMLInputElement>(null);
   const { colorScheme } = useMantineColorScheme();
   const { t } = useTranslation();
@@ -15,7 +15,7 @@ const LandingPage = () => {
   const [isUploadHover, setIsUploadHover] = React.useState(false);
 
   const handleFileDrop = async (files: File[]) => {
-    await addMultipleFiles(files);
+    await addFiles(files);
   };
 
   const handleOpenFilesModal = () => {
@@ -29,7 +29,7 @@ const LandingPage = () => {
   const handleFileSelect = async (event: React.ChangeEvent<HTMLInputElement>) => {
     const files = Array.from(event.target.files || []);
     if (files.length > 0) {
-      await addMultipleFiles(files);
+      await addFiles(files);
     }
     // Reset the input so the same file can be selected again
     event.target.value = '';

frontend/src/components/shared/ToolChain.tsx

@@ -0,0 +1,153 @@
+/**
+ * Reusable ToolChain component with smart truncation and tooltip expansion
+ * Used across FileListItem, FileDetails, and FileThumbnail for consistent display
+ */
+
+import React from 'react';
+import { Text, Tooltip, Badge, Group } from '@mantine/core';
+import { ToolOperation } from '../../types/file';
+
+interface ToolChainProps {
+  toolChain: ToolOperation[];
+  maxWidth?: string;
+  displayStyle?: 'text' | 'badges' | 'compact';
+  size?: 'xs' | 'sm' | 'md';
+  color?: string;
+}
+
+const ToolChain: React.FC<ToolChainProps> = ({
+  toolChain,
+  maxWidth = '100%',
+  displayStyle = 'text',
+  size = 'xs',
+  color = 'var(--mantine-color-blue-7)'
+}) => {
+  if (!toolChain || toolChain.length === 0) return null;
+
+  const toolNames = toolChain.map(tool => tool.toolName);
+
+  // Create full tool chain for tooltip
+  const fullChainDisplay = displayStyle === 'badges' ? (
+    <Group gap="xs" wrap="wrap">
+      {toolChain.map((tool, index) => (
+        <React.Fragment key={`${tool.toolName}-${index}`}>
+          <Badge size="sm" variant="light" color="blue">
+            {tool.toolName}
+          </Badge>
+          {index < toolChain.length - 1 && (
+            <Text size="sm" c="dimmed">→</Text>
+          )}
+        </React.Fragment>
+      ))}
+    </Group>
+  ) : (
+    <Text size="sm">{toolNames.join(' → ')}</Text>
+  );
+
+  // Create truncated display based on available space
+  const getTruncatedDisplay = () => {
+    if (toolNames.length <= 2) {
+      // Show all tools if 2 or fewer
+      return { text: toolNames.join(' → '), isTruncated: false };
+    } else {
+      // Show first tool ... last tool for longer chains
+      return {
+        text: `${toolNames[0]} → +${toolNames.length-2} → ${toolNames[toolNames.length - 1]}`,
+        isTruncated: true
+      };
+    }
+  };
+
+  const { text: truncatedText, isTruncated } = getTruncatedDisplay();
+
+  // Compact style for very small spaces
+  if (displayStyle === 'compact') {
+    const compactText = toolNames.length === 1 ? toolNames[0] : `${toolNames.length} tools`;
+    const isCompactTruncated = toolNames.length > 1;
+
+    const compactElement = (
+      <Text
+        size={size}
+        style={{
+          color,
+          fontWeight: 500,
+          whiteSpace: 'nowrap',
+          overflow: 'hidden',
+          textOverflow: 'ellipsis',
+          maxWidth: `${maxWidth}`,
+          cursor: isCompactTruncated ? 'help' : 'default'
+        }}
+      >
+        {compactText}
+      </Text>
+    );
+
+    return isCompactTruncated ? (
+      <Tooltip label={fullChainDisplay} multiline withinPortal>
+        {compactElement}
+      </Tooltip>
+    ) : compactElement;
+  }
+
+  // Badge style for file details
+  if (displayStyle === 'badges') {
+    const isBadgesTruncated = toolChain.length > 3;
+
+    const badgesElement = (
+      <div style={{ maxWidth: `${maxWidth}`, overflow: 'hidden' }}>
+        <Group gap="2px" wrap="nowrap">
+          {toolChain.slice(0, 3).map((tool, index) => (
+            <React.Fragment key={`${tool.toolName}-${index}`}>
+              <Badge size={size} variant="light" color="blue">
+                {tool.toolName}
+              </Badge>
+              {index < Math.min(toolChain.length - 1, 2) && (
+                <Text size="xs" c="dimmed">→</Text>
+              )}
+            </React.Fragment>
+          ))}
+          {toolChain.length > 3 && (
+            <>
+              <Text size="xs" c="dimmed">...</Text>
+              <Badge size={size} variant="light" color="blue">
+                {toolChain[toolChain.length - 1].toolName}
+              </Badge>
+            </>
+          )}
+        </Group>
+      </div>
+    );
+
+    return isBadgesTruncated ? (
+      <Tooltip label={`${toolNames.join(' → ')}`} withinPortal>
+        {badgesElement}
+      </Tooltip>
+    ) : badgesElement;
+  }
+
+  // Text style (default) for file list items
+  const textElement = (
+    <Text
+      size={size}
+      style={{
+        color,
+        fontWeight: 500,
+        whiteSpace: 'nowrap',
+        overflow: 'hidden',
+        textOverflow: 'ellipsis',
+        maxWidth: `${maxWidth}`,
+        cursor: isTruncated ? 'help' : 'default'
+      }}
+    >
+      {truncatedText}
+    </Text>
+  );
+
+  return isTruncated ? (
+    <Tooltip label={fullChainDisplay} withinPortal>
+      {textElement}
+    </Tooltip>
+  ) : textElement;
+};
+
+export default ToolChain;

frontend/src/components/shared/filePreview/DocumentThumbnail.tsx

@@ -1,10 +1,10 @@
 import React from 'react';
 import { Box, Center, Image } from '@mantine/core';
 import PictureAsPdfIcon from '@mui/icons-material/PictureAsPdf';
-import { FileMetadata } from '../../../types/file';
+import { StirlingFileStub } from '../../../types/fileContext';
 
 export interface DocumentThumbnailProps {
-  file: File | FileMetadata | null;
+  file: File | StirlingFileStub | null;
   thumbnail?: string | null;
   style?: React.CSSProperties;
   onClick?: () => void;

frontend/src/components/tools/shared/FileStatusIndicator.tsx

@@ -18,7 +18,7 @@ const FileStatusIndicator = ({
   minFiles = 1,
 }: FileStatusIndicatorProps) => {
   const { t } = useTranslation();
-  const { openFilesModal, onFilesSelect } = useFilesModalContext();
+  const { openFilesModal, onFileUpload } = useFilesModalContext();
   const { files: stirlingFileStubs } = useAllFiles();
   const { loadRecentFiles } = useFileManager();
   const [hasRecentFiles, setHasRecentFiles] = useState<boolean | null>(null);
@@ -45,7 +45,7 @@ const FileStatusIndicator = ({
     input.onchange = (event) => {
       const files = Array.from((event.target as HTMLInputElement).files || []);
       if (files.length > 0) {
-        onFilesSelect(files);
+        onFileUpload(files);
       }
     };
     input.click();

frontend/src/components/tools/split/SplitSettings.tsx

@@ -1,6 +1,7 @@
-import { Stack, TextInput, Select, Checkbox } from '@mantine/core';
+import { Stack, TextInput, Checkbox, Anchor, Text } from '@mantine/core';
+import LocalIcon from '../../shared/LocalIcon';
 import { useTranslation } from 'react-i18next';
-import { isSplitMode, isSplitType, SPLIT_MODES, SPLIT_TYPES } from '../../../constants/splitConstants';
+import { SPLIT_METHODS } from '../../../constants/splitConstants';
 import { SplitParameters } from '../../../hooks/tools/split/useSplitParameters';
 
 export interface SplitSettingsProps {
@@ -57,28 +58,37 @@ const SplitSettings = ({
     </Stack>
   );
 
-  const renderBySizeOrCountForm = () => (
-    <Stack gap="sm">
-      <Select
-        label={t("split-by-size-or-count.type.label", "Split Type")}
-        value={parameters.splitType}
-        onChange={(v) => isSplitType(v) && onParameterChange('splitType', v)}
-        disabled={disabled}
-        data={[
-          { value: SPLIT_TYPES.SIZE, label: t("split-by-size-or-count.type.size", "By Size") },
-          { value: SPLIT_TYPES.PAGES, label: t("split-by-size-or-count.type.pageCount", "By Page Count") },
-          { value: SPLIT_TYPES.DOCS, label: t("split-by-size-or-count.type.docCount", "By Document Count") },
-        ]}
-      />
+  const renderSplitValueForm = () => {
+    let label, placeholder;
+
+    switch (parameters.method) {
+      case SPLIT_METHODS.BY_SIZE:
+        label = t("split.value.fileSize.label", "File Size");
+        placeholder = t("split.value.fileSize.placeholder", "e.g. 10MB, 500KB");
+        break;
+      case SPLIT_METHODS.BY_PAGE_COUNT:
+        label = t("split.value.pageCount.label", "Pages per File");
+        placeholder = t("split.value.pageCount.placeholder", "e.g. 5, 10");
+        break;
+      case SPLIT_METHODS.BY_DOC_COUNT:
+        label = t("split.value.docCount.label", "Number of Files");
+        placeholder = t("split.value.docCount.placeholder", "e.g. 3, 5");
+        break;
+      default:
+        label = t("split-by-size-or-count.value.label", "Split Value");
+        placeholder = t("split-by-size-or-count.value.placeholder", "e.g. 10MB or 5 pages");
+    }
+
+    return (
       <TextInput
-        label={t("split-by-size-or-count.value.label", "Split Value")}
-        placeholder={t("split-by-size-or-count.value.placeholder", "e.g. 10MB or 5 pages")}
+        label={label}
+        placeholder={placeholder}
         value={parameters.splitValue}
         onChange={(e) => onParameterChange('splitValue', e.target.value)}
         disabled={disabled}
       />
-    </Stack>
-  );
+    );
+  };
 
   const renderByChaptersForm = () => (
     <Stack gap="sm">
@@ -104,28 +114,48 @@ const SplitSettings = ({
     </Stack>
   );
 
+  const renderByPageDividerForm = () => (
+    <Stack gap="sm">
+      <Anchor
+        href="https://stirlingpdf.io/files/Auto%20Splitter%20Divider%20(with%20instructions).pdf"
+        target="_blank"
+        size="sm"
+        style={{ display: 'flex', alignItems: 'center', gap: '0.5rem' }}
+      >
+        <LocalIcon icon="download-rounded" width="2rem" height="2rem" />
+        {t("autoSplitPDF.dividerDownload2", "Download 'Auto Splitter Divider (with instructions).pdf'")}
+      </Anchor>
+
+      <Checkbox
+        label={t("autoSplitPDF.duplexMode", "Duplex Mode (Front and back scanning)")}
+        checked={parameters.duplexMode}
+        onChange={(e) => onParameterChange('duplexMode', e.currentTarget.checked)}
+        disabled={disabled}
+      />
+    </Stack>
+  );
+
+  // Don't render anything if no method is selected
+  if (!parameters.method) {
+    return (
+      <Stack gap="sm">
+        <Text c="dimmed" ta="center">
+          {t("split.settings.selectMethodFirst", "Please select a split method first")}
+        </Text>
+      </Stack>
+    );
+  }
+
   return (
     <Stack gap="md">
-      {/* Mode Selector */}
-      <Select
-        label="Choose split method"
-        placeholder="Select how to split the PDF"
-        value={parameters.mode}
-        onChange={(v) => isSplitMode(v) && onParameterChange('mode', v)}
-        disabled={disabled}
-        data={[
-          { value: SPLIT_MODES.BY_PAGES, label: t("split.header", "Split by Pages") + " (e.g. 1,3,5-10)" },
-          { value: SPLIT_MODES.BY_SECTIONS, label: t("split-by-sections.title", "Split by Grid Sections") },
-          { value: SPLIT_MODES.BY_SIZE_OR_COUNT, label: t("split-by-size-or-count.title", "Split by Size or Count") },
-          { value: SPLIT_MODES.BY_CHAPTERS, label: t("splitByChapters.title", "Split by Chapters") },
-        ]}
-      />
-
-      {/* Parameter Form */}
-      {parameters.mode === SPLIT_MODES.BY_PAGES && renderByPagesForm()}
-      {parameters.mode === SPLIT_MODES.BY_SECTIONS && renderBySectionsForm()}
-      {parameters.mode === SPLIT_MODES.BY_SIZE_OR_COUNT && renderBySizeOrCountForm()}
-      {parameters.mode === SPLIT_MODES.BY_CHAPTERS && renderByChaptersForm()}
+      {/* Method-Specific Form */}
+      {parameters.method === SPLIT_METHODS.BY_PAGES && renderByPagesForm()}
+      {parameters.method === SPLIT_METHODS.BY_SECTIONS && renderBySectionsForm()}
+      {(parameters.method === SPLIT_METHODS.BY_SIZE ||
+        parameters.method === SPLIT_METHODS.BY_PAGE_COUNT ||
+        parameters.method === SPLIT_METHODS.BY_DOC_COUNT) && renderSplitValueForm()}
+      {parameters.method === SPLIT_METHODS.BY_CHAPTERS && renderByChaptersForm()}
+      {parameters.method === SPLIT_METHODS.BY_PAGE_DIVIDER && renderByPageDividerForm()}
     </Stack>
   );
 }

frontend/src/components/tooltips/useSplitMethodTips.ts

@@ -0,0 +1,24 @@
+import { useTranslation } from 'react-i18next';
+import { TooltipContent } from '../../types/tips';
+
+export const useSplitMethodTips = (): TooltipContent => {
+  const { t } = useTranslation();
+
+  return {
+    header: {
+      title: t("split.methodSelection.tooltip.title", "Choose Your Split Method")
+    },
+    tips: [
+      {
+        title: t("split.methodSelection.tooltip.header.title", "Split Method Selection"),
+        description: t("split.methodSelection.tooltip.header.text", "Choose how you want to split your PDF document. Each method is optimized for different use cases and document types."),
+        bullets: [
+          t("split.methodSelection.tooltip.bullet1", "Click on a method card to select it"),
+          t("split.methodSelection.tooltip.bullet2", "Hover over each card to see a quick description"),
+          t("split.methodSelection.tooltip.bullet3", "The settings step will appear after you select a method"),
+          t("split.methodSelection.tooltip.bullet4", "You can change methods at any time before processing")
+        ]
+      }
+    ]
+  };
+};

frontend/src/components/tooltips/useSplitSettingsTips.ts

@@ -0,0 +1,134 @@
+import { useTranslation } from 'react-i18next';
+import { TooltipContent } from '../../types/tips';
+import { SPLIT_METHODS, type SplitMethod } from '../../constants/splitConstants';
+
+export const useSplitSettingsTips = (method: SplitMethod | ''): TooltipContent | null => {
+  const { t } = useTranslation();
+
+  if (!method) return null;
+
+  const tooltipMap: Record<SplitMethod, TooltipContent> = {
+    [SPLIT_METHODS.BY_PAGES]: {
+      header: {
+        title: t("split.tooltip.byPages.title", "Split at Page Numbers")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.byPages.title", "Split at Page Numbers"),
+          description: t("split.tooltip.byPages.text", "Extract specific pages or ranges from your PDF. Use commas to separate individual pages and hyphens for ranges."),
+          bullets: [
+            t("split.tooltip.byPages.bullet1", "Single pages: 1,3,5"),
+            t("split.tooltip.byPages.bullet2", "Page ranges: 1-5,10-15"),
+            t("split.tooltip.byPages.bullet3", "Mixed: 1,3-7,12,15-20")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_SECTIONS]: {
+      header: {
+        title: t("split.tooltip.bySections.title", "Split by Grid Sections")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.bySections.title", "Split by Grid Sections"),
+          description: t("split.tooltip.bySections.text", "Divide each page into a grid of sections. Useful for splitting documents with multiple columns or extracting specific areas."),
+          bullets: [
+            t("split.tooltip.bySections.bullet1", "Horizontal: Number of rows to create"),
+            t("split.tooltip.bySections.bullet2", "Vertical: Number of columns to create"),
+            t("split.tooltip.bySections.bullet3", "Merge: Combine all sections into one PDF")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_SIZE]: {
+      header: {
+        title: t("split.tooltip.bySize.title", "Split by File Size")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.bySize.title", "Split by File Size"),
+          description: t("split.tooltip.bySize.text", "Create multiple PDFs that don't exceed a specified file size. Ideal for file size limitations or email attachments."),
+          bullets: [
+            t("split.tooltip.bySize.bullet1", "Use MB for larger files (e.g., 10MB)"),
+            t("split.tooltip.bySize.bullet2", "Use KB for smaller files (e.g., 500KB)"),
+            t("split.tooltip.bySize.bullet3", "System will split at page boundaries")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_PAGE_COUNT]: {
+      header: {
+        title: t("split.tooltip.byPageCount.title", "Split by Page Count")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.byPageCount.title", "Split by Page Count"),
+          description: t("split.tooltip.byPageCount.text", "Create multiple PDFs with a specific number of pages each. Perfect for creating uniform document chunks."),
+          bullets: [
+            t("split.tooltip.byPageCount.bullet1", "Enter the number of pages per output file"),
+            t("split.tooltip.byPageCount.bullet2", "Last file may have fewer pages if not evenly divisible"),
+            t("split.tooltip.byPageCount.bullet3", "Useful for batch processing workflows")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_DOC_COUNT]: {
+      header: {
+        title: t("split.tooltip.byDocCount.title", "Split by Document Count")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.byDocCount.title", "Split by Document Count"),
+          description: t("split.tooltip.byDocCount.text", "Create a specific number of output files by evenly distributing pages across them."),
+          bullets: [
+            t("split.tooltip.byDocCount.bullet1", "Enter the number of output files you want"),
+            t("split.tooltip.byDocCount.bullet2", "Pages are distributed as evenly as possible"),
+            t("split.tooltip.byDocCount.bullet3", "Useful when you need a specific number of files")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_CHAPTERS]: {
+      header: {
+        title: t("split.tooltip.byChapters.title", "Split by Chapters")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.byChapters.title", "Split by Chapters"),
+          description: t("split.tooltip.byChapters.text", "Use PDF bookmarks to automatically split at chapter boundaries. Requires PDFs with bookmark structure."),
+          bullets: [
+            t("split.tooltip.byChapters.bullet1", "Bookmark Level: Which level to split on (1=top level)"),
+            t("split.tooltip.byChapters.bullet2", "Include Metadata: Preserve document properties"),
+            t("split.tooltip.byChapters.bullet3", "Allow Duplicates: Handle repeated bookmark names")
+          ]
+        }
+      ]
+    },
+
+    [SPLIT_METHODS.BY_PAGE_DIVIDER]: {
+      header: {
+        title: t("split.tooltip.byPageDivider.title", "Split by Page Divider")
+      },
+      tips: [
+        {
+          title: t("split.tooltip.byPageDivider.title", "Split by Page Divider"),
+          description: t("split.tooltip.byPageDivider.text", "Automatically split scanned documents using physical divider sheets with QR codes. Perfect for processing multiple documents scanned together."),
+          bullets: [
+            t("split.tooltip.byPageDivider.bullet1", "Print divider sheets from the download link"),
+            t("split.tooltip.byPageDivider.bullet2", "Insert divider sheets between your documents"),
+            t("split.tooltip.byPageDivider.bullet3", "Scan all documents together as one PDF"),
+            t("split.tooltip.byPageDivider.bullet4", "Upload - divider pages are automatically detected and removed"),
+            t("split.tooltip.byPageDivider.bullet5", "Enable Duplex Mode if scanning both sides of divider sheets")
+          ]
+        }
+      ]
+    }
+  };
+
+  return tooltipMap[method];
+};

frontend/src/components/viewer/Viewer.tsx

@@ -372,11 +372,12 @@ const Viewer = ({
         else if (effectiveFile.url?.startsWith('indexeddb:')) {
           const fileId = effectiveFile.url.replace('indexeddb:', '') as FileId /* FIX ME: Not sure this is right - at least probably not the right place for this logic */;
 
-          // Get data directly from IndexedDB
-          const arrayBuffer = await fileStorage.getFileData(fileId);
-          if (!arrayBuffer) {
+          // Get file directly from IndexedDB
+          const file = await fileStorage.getStirlingFile(fileId);
+          if (!file) {
             throw new Error('File not found in IndexedDB - may have been purged by browser');
           }
+          const arrayBuffer = await file.arrayBuffer();
 
           // Store reference for cleanup
           currentArrayBufferRef.current = arrayBuffer;

frontend/src/constants/splitConstants.ts

@@ -1,30 +1,78 @@
-export const SPLIT_MODES = {
+export const SPLIT_METHODS = {
   BY_PAGES: 'byPages',
   BY_SECTIONS: 'bySections',
-  BY_SIZE_OR_COUNT: 'bySizeOrCount',
-  BY_CHAPTERS: 'byChapters'
+  BY_SIZE: 'bySize',
+  BY_PAGE_COUNT: 'byPageCount',
+  BY_DOC_COUNT: 'byDocCount',
+  BY_CHAPTERS: 'byChapters',
+  BY_PAGE_DIVIDER: 'byPageDivider'
 } as const;
 
-export const SPLIT_TYPES = {
-  SIZE: 'size',
-  PAGES: 'pages',
-  DOCS: 'docs'
-} as const;
 
 export const ENDPOINTS = {
-  [SPLIT_MODES.BY_PAGES]: 'split-pages',
-  [SPLIT_MODES.BY_SECTIONS]: 'split-pdf-by-sections',
-  [SPLIT_MODES.BY_SIZE_OR_COUNT]: 'split-by-size-or-count',
-  [SPLIT_MODES.BY_CHAPTERS]: 'split-pdf-by-chapters'
+  [SPLIT_METHODS.BY_PAGES]: 'split-pages',
+  [SPLIT_METHODS.BY_SECTIONS]: 'split-pdf-by-sections',
+  [SPLIT_METHODS.BY_SIZE]: 'split-by-size-or-count',
+  [SPLIT_METHODS.BY_PAGE_COUNT]: 'split-by-size-or-count',
+  [SPLIT_METHODS.BY_DOC_COUNT]: 'split-by-size-or-count',
+  [SPLIT_METHODS.BY_CHAPTERS]: 'split-pdf-by-chapters',
+  [SPLIT_METHODS.BY_PAGE_DIVIDER]: 'auto-split-pdf'
 } as const;
 
-export type SplitMode = typeof SPLIT_MODES[keyof typeof SPLIT_MODES];
-export type SplitType = typeof SPLIT_TYPES[keyof typeof SPLIT_TYPES];
-
-export const isSplitMode = (value: string | null): value is SplitMode => {
-  return Object.values(SPLIT_MODES).includes(value as SplitMode);
+export type SplitMethod = typeof SPLIT_METHODS[keyof typeof SPLIT_METHODS];
+export const isSplitMethod = (value: string | null): value is SplitMethod => {
+  return Object.values(SPLIT_METHODS).includes(value as SplitMethod);
 }
 
-export const isSplitType = (value: string | null): value is SplitType => {
-  return Object.values(SPLIT_TYPES).includes(value as SplitType);
+import { CardOption } from '../components/shared/CardSelector';
+
+export interface MethodOption extends CardOption<SplitMethod> {
+  tooltipKey: string;
 }
+
+export const METHOD_OPTIONS: MethodOption[] = [
+  {
+    value: SPLIT_METHODS.BY_PAGES,
+    prefixKey: "split.methods.prefix.splitAt",
+    nameKey: "split.methods.byPages.name",
+    tooltipKey: "split.methods.byPages.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_CHAPTERS,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.byChapters.name",
+    tooltipKey: "split.methods.byChapters.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_SECTIONS,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.bySections.name",
+    tooltipKey: "split.methods.bySections.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_SIZE,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.bySize.name",
+    tooltipKey: "split.methods.bySize.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_PAGE_COUNT,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.byPageCount.name",
+    tooltipKey: "split.methods.byPageCount.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_DOC_COUNT,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.byDocCount.name",
+    tooltipKey: "split.methods.byDocCount.tooltip"
+  },
+  {
+    value: SPLIT_METHODS.BY_PAGE_DIVIDER,
+    prefixKey: "split.methods.prefix.splitBy",
+    nameKey: "split.methods.byPageDivider.name",
+    tooltipKey: "split.methods.byPageDivider.tooltip"
+  }
+];
+
+

frontend/src/contexts/FileContext.tsx

@@ -22,13 +22,12 @@ import {
   FileId,
   StirlingFileStub,
   StirlingFile,
-  createStirlingFile
 } from '../types/fileContext';
 
 // Import modular components
 import { fileContextReducer, initialFileContextState } from './file/FileReducer';
 import { createFileSelectors } from './file/fileSelectors';
-import { AddedFile, addFiles, consumeFiles, undoConsumeFiles, createFileActions } from './file/fileActions';
+import { addFiles, addStirlingFileStubs, consumeFiles, undoConsumeFiles, createFileActions } from './file/fileActions';
 import { FileLifecycleManager } from './file/lifecycle';
 import { FileStateContext, FileActionsContext } from './file/contexts';
 import { IndexedDBProvider, useIndexedDB } from './IndexedDBContext';
@@ -73,58 +72,44 @@ function FileContextInner({
     dispatch({ type: 'SET_UNSAVED_CHANGES', payload: { hasChanges } });
   }, []);
 
-  const selectFiles = (addedFilesWithIds: AddedFile[]) => {
+  const selectFiles = (stirlingFiles: StirlingFile[]) => {
     const currentSelection = stateRef.current.ui.selectedFileIds;
-    const newFileIds = addedFilesWithIds.map(({ id }) => id);
+    const newFileIds = stirlingFiles.map(stirlingFile => stirlingFile.fileId);
     dispatch({ type: 'SET_SELECTED_FILES', payload: { fileIds: [...currentSelection, ...newFileIds] } });
   }
 
   // File operations using unified addFiles helper with persistence
   const addRawFiles = useCallback(async (files: File[], options?: { insertAfterPageId?: string; selectFiles?: boolean }): Promise<StirlingFile[]> => {
-    const addedFilesWithIds = await addFiles('raw', { files, ...options }, stateRef, filesRef, dispatch, lifecycleManager);
+    const stirlingFiles = await addFiles({ files, ...options }, stateRef, filesRef, dispatch, lifecycleManager, enablePersistence);
 
     // Auto-select the newly added files if requested
-    if (options?.selectFiles && addedFilesWithIds.length > 0) {
-      selectFiles(addedFilesWithIds);
+    if (options?.selectFiles && stirlingFiles.length > 0) {
+      selectFiles(stirlingFiles);
     }
 
-    // Persist to IndexedDB if enabled
-    if (indexedDB && enablePersistence && addedFilesWithIds.length > 0) {
-      await Promise.all(addedFilesWithIds.map(async ({ file, id, thumbnail }) => {
-        try {
-          await indexedDB.saveFile(file, id, thumbnail);
-        } catch (error) {
-          console.error('Failed to persist file to IndexedDB:', file.name, error);
-        }
-      }));
-    }
+    return stirlingFiles;
+  }, [enablePersistence]);
 
-    return addedFilesWithIds.map(({ file, id }) => createStirlingFile(file, id));
-  }, [indexedDB, enablePersistence]);
-
-  const addProcessedFiles = useCallback(async (filesWithThumbnails: Array<{ file: File; thumbnail?: string; pageCount?: number }>): Promise<StirlingFile[]> => {
-    const result = await addFiles('processed', { filesWithThumbnails }, stateRef, filesRef, dispatch, lifecycleManager);
-    return result.map(({ file, id }) => createStirlingFile(file, id));
-  }, []);
-
-  const addStoredFiles = useCallback(async (filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: any }>, options?: { selectFiles?: boolean }): Promise<StirlingFile[]> => {
-    const result = await addFiles('stored', { filesWithMetadata }, stateRef, filesRef, dispatch, lifecycleManager);
+  const addStirlingFileStubsAction = useCallback(async (stirlingFileStubs: StirlingFileStub[], options?: { insertAfterPageId?: string; selectFiles?: boolean }): Promise<StirlingFile[]> => {
+    // StirlingFileStubs preserve all metadata - perfect for FileManager use case!
+    const result = await addStirlingFileStubs(stirlingFileStubs, options, stateRef, filesRef, dispatch, lifecycleManager);
 
     // Auto-select the newly added files if requested
     if (options?.selectFiles && result.length > 0) {
       selectFiles(result);
     }
 
-    return result.map(({ file, id }) => createStirlingFile(file, id));
+    return result;
   }, []);
 
+
   // Action creators
   const baseActions = useMemo(() => createFileActions(dispatch), []);
 
   // Helper functions for pinned files
-  const consumeFilesWrapper = useCallback(async (inputFileIds: FileId[], outputFiles: File[]): Promise<FileId[]> => {
-    return consumeFiles(inputFileIds, outputFiles, filesRef, dispatch, indexedDB);
-  }, [indexedDB]);
+  const consumeFilesWrapper = useCallback(async (inputFileIds: FileId[], outputStirlingFiles: StirlingFile[], outputStirlingFileStubs: StirlingFileStub[]): Promise<FileId[]> => {
+    return consumeFiles(inputFileIds, outputStirlingFiles, outputStirlingFileStubs, filesRef, dispatch);
+  }, []);
 
   const undoConsumeFilesWrapper = useCallback(async (inputFiles: File[], inputStirlingFileStubs: StirlingFileStub[], outputFileIds: FileId[]): Promise<void> => {
     return undoConsumeFiles(inputFiles, inputStirlingFileStubs, outputFileIds, filesRef, dispatch, indexedDB);
@@ -143,8 +128,7 @@ function FileContextInner({
   const actions = useMemo<FileContextActions>(() => ({
     ...baseActions,
     addFiles: addRawFiles,
-    addProcessedFiles,
-    addStoredFiles,
+    addStirlingFileStubs: addStirlingFileStubsAction,
     removeFiles: async (fileIds: FileId[], deleteFromStorage?: boolean) => {
       // Remove from memory and cleanup resources
       lifecycleManager.removeFiles(fileIds, stateRef);
@@ -199,8 +183,7 @@ function FileContextInner({
   }), [
     baseActions,
     addRawFiles,
-    addProcessedFiles,
-    addStoredFiles,
+    addStirlingFileStubsAction,
     lifecycleManager,
     setHasUnsavedChanges,
     consumeFilesWrapper,

frontend/src/contexts/FileManagerContext.tsx

@@ -1,8 +1,9 @@
 import React, { createContext, useContext, useState, useRef, useCallback, useEffect, useMemo } from 'react';
-import { FileMetadata } from '../types/file';
 import { fileStorage } from '../services/fileStorage';
+import { StirlingFileStub } from '../types/fileContext';
 import { downloadFiles } from '../utils/downloadUtils';
 import { FileId } from '../types/file';
+import { groupFilesByOriginal } from '../utils/fileHistoryUtils';
 
 // Type for the context value - now contains everything directly
 interface FileManagerContextValue {
@@ -10,27 +11,34 @@ interface FileManagerContextValue {
   activeSource: 'recent' | 'local' | 'drive';
   selectedFileIds: FileId[];
   searchTerm: string;
-  selectedFiles: FileMetadata[];
-  filteredFiles: FileMetadata[];
+  selectedFiles: StirlingFileStub[];
+  filteredFiles: StirlingFileStub[];
   fileInputRef: React.RefObject<HTMLInputElement | null>;
-  selectedFilesSet: Set<string>;
+  selectedFilesSet: Set<FileId>;
+  expandedFileIds: Set<FileId>;
+  fileGroups: Map<FileId, StirlingFileStub[]>;
+  loadedHistoryFiles: Map<FileId, StirlingFileStub[]>;
 
   // Handlers
   onSourceChange: (source: 'recent' | 'local' | 'drive') => void;
   onLocalFileClick: () => void;
-  onFileSelect: (file: FileMetadata, index: number, shiftKey?: boolean) => void;
+  onFileSelect: (file: StirlingFileStub, index: number, shiftKey?: boolean) => void;
   onFileRemove: (index: number) => void;
-  onFileDoubleClick: (file: FileMetadata) => void;
+  onHistoryFileRemove: (file: StirlingFileStub) => void;
+  onFileDoubleClick: (file: StirlingFileStub) => void;
   onOpenFiles: () => void;
   onSearchChange: (value: string) => void;
   onFileInputChange: (event: React.ChangeEvent<HTMLInputElement>) => void;
   onSelectAll: () => void;
   onDeleteSelected: () => void;
   onDownloadSelected: () => void;
-  onDownloadSingle: (file: FileMetadata) => void;
+  onDownloadSingle: (file: StirlingFileStub) => void;
+  onToggleExpansion: (fileId: FileId) => void;
+  onAddToRecents: (file: StirlingFileStub) => void;
+  onNewFilesSelect: (files: File[]) => void;
 
   // External props
-  recentFiles: FileMetadata[];
+  recentFiles: StirlingFileStub[];
   isFileSupported: (fileName: string) => boolean;
   modalHeight: string;
 }
@@ -41,8 +49,8 @@ const FileManagerContext = createContext<FileManagerContextValue | null>(null);
 // Provider component props
 interface FileManagerProviderProps {
   children: React.ReactNode;
-  recentFiles: FileMetadata[];
-  onFilesSelected: (files: FileMetadata[]) => void; // For selecting stored files
+  recentFiles: StirlingFileStub[];
+  onRecentFilesSelected: (files: StirlingFileStub[]) => void; // For selecting stored files
   onNewFilesSelect: (files: File[]) => void; // For uploading new local files
   onClose: () => void;
   isFileSupported: (fileName: string) => boolean;
@@ -55,7 +63,7 @@ interface FileManagerProviderProps {
 export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
   children,
   recentFiles,
-  onFilesSelected,
+  onRecentFilesSelected,
   onNewFilesSelect,
   onClose,
   isFileSupported,
@@ -68,19 +76,44 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
   const [selectedFileIds, setSelectedFileIds] = useState<FileId[]>([]);
   const [searchTerm, setSearchTerm] = useState('');
   const [lastClickedIndex, setLastClickedIndex] = useState<number | null>(null);
+  const [expandedFileIds, setExpandedFileIds] = useState<Set<FileId>>(new Set());
+  const [loadedHistoryFiles, setLoadedHistoryFiles] = useState<Map<FileId, StirlingFileStub[]>>(new Map()); // Cache for loaded history
   const fileInputRef = useRef<HTMLInputElement>(null);
 
   // Track blob URLs for cleanup
   const createdBlobUrls = useRef<Set<string>>(new Set());
 
+
   // Computed values (with null safety)
   const selectedFilesSet = new Set(selectedFileIds);
 
-  const selectedFiles = selectedFileIds.length === 0 ? [] :
-    (recentFiles || []).filter(file => selectedFilesSet.has(file.id));
+  // Group files by original file ID for version management
+  const fileGroups = useMemo(() => {
+    if (!recentFiles || recentFiles.length === 0) return new Map();
 
-  const filteredFiles = !searchTerm ? recentFiles || [] :
-    (recentFiles || []).filter(file =>
+    // Convert StirlingFileStub to FileRecord-like objects for grouping utility
+    const recordsForGrouping = recentFiles.map(file => ({
+      ...file,
+      originalFileId: file.originalFileId,
+      versionNumber: file.versionNumber || 1
+    }));
+
+    return groupFilesByOriginal(recordsForGrouping);
+  }, [recentFiles]);
+
+  // Get files to display with expansion logic
+  const displayFiles = useMemo(() => {
+    if (!recentFiles || recentFiles.length === 0) return [];
+
+    // Only return leaf files - history files will be handled by separate components
+    return recentFiles;
+  }, [recentFiles]);
+
+  const selectedFiles = selectedFileIds.length === 0 ? [] :
+    displayFiles.filter(file => selectedFilesSet.has(file.id));
+
+  const filteredFiles = !searchTerm ? displayFiles :
+    displayFiles.filter(file =>
       file.name.toLowerCase().includes(searchTerm.toLowerCase())
     );
 
@@ -97,7 +130,7 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     fileInputRef.current?.click();
   }, []);
 
-  const handleFileSelect = useCallback((file: FileMetadata, currentIndex: number, shiftKey?: boolean) => {
+  const handleFileSelect = useCallback((file: StirlingFileStub, currentIndex: number, shiftKey?: boolean) => {
     const fileId = file.id;
     if (!fileId) return;
 
@@ -138,27 +171,214 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     }
   }, [filteredFiles, lastClickedIndex]);
 
-  const handleFileRemove = useCallback((index: number) => {
+  // Helper function to safely determine which files can be deleted
+  const getSafeFilesToDelete = useCallback((
+    fileIds: FileId[],
+    allStoredStubs: StirlingFileStub[]
+  ): FileId[] => {
+    const fileMap = new Map(allStoredStubs.map(f => [f.id, f]));
+    const filesToDelete = new Set<FileId>();
+    const filesToPreserve = new Set<FileId>();
+
+    // First, identify all files in the lineages of the leaf files being deleted
+    for (const leafFileId of fileIds) {
+      const currentFile = fileMap.get(leafFileId);
+      if (!currentFile) continue;
+
+      // Always include the leaf file itself for deletion
+      filesToDelete.add(leafFileId);
+
+      // If this is a processed file with history, trace back through its lineage
+      if (currentFile.versionNumber && currentFile.versionNumber > 1) {
+        const originalFileId = currentFile.originalFileId || currentFile.id;
+
+        // Find all files in this history chain
+        const chainFiles = allStoredStubs.filter((file: StirlingFileStub) =>
+          (file.originalFileId || file.id) === originalFileId
+        );
+
+        // Add all files in this lineage as candidates for deletion
+        chainFiles.forEach(file => filesToDelete.add(file.id));
+      }
+    }
+
+    // Now identify files that must be preserved because they're referenced by OTHER lineages
+    for (const file of allStoredStubs) {
+      const fileOriginalId = file.originalFileId || file.id;
+
+      // If this file is a leaf node (not being deleted) and its lineage overlaps with files we want to delete
+      if (file.isLeaf !== false && !fileIds.includes(file.id)) {
+        // Find all files in this preserved lineage
+        const preservedChainFiles = allStoredStubs.filter((chainFile: StirlingFileStub) =>
+          (chainFile.originalFileId || chainFile.id) === fileOriginalId
+        );
+
+        // Mark all files in this preserved lineage as must-preserve
+        preservedChainFiles.forEach(chainFile => filesToPreserve.add(chainFile.id));
+      }
+    }
+
+    // Final list: files to delete minus files that must be preserved
+    let safeToDelete = Array.from(filesToDelete).filter(fileId => !filesToPreserve.has(fileId));
+
+    // Check for orphaned non-leaf files after main deletion
+    const remainingFiles = allStoredStubs.filter(file => !safeToDelete.includes(file.id));
+    const orphanedNonLeafFiles: FileId[] = [];
+
+    for (const file of remainingFiles) {
+      // Only check non-leaf files (files that have been processed and have children)
+      if (file.isLeaf === false) {
+        const fileOriginalId = file.originalFileId || file.id;
+
+        // Check if this non-leaf file has any living descendants
+        const hasLivingDescendants = remainingFiles.some(otherFile => {
+          // Check if otherFile is a descendant of this file
+          const otherOriginalId = otherFile.originalFileId || otherFile.id;
+          return (
+            // Direct parent relationship
+            otherFile.parentFileId === file.id ||
+            // Same lineage but different from this file
+            (otherOriginalId === fileOriginalId && otherFile.id !== file.id)
+          );
+        });
+
+        if (!hasLivingDescendants) {
+          orphanedNonLeafFiles.push(file.id);
+        }
+      }
+    }
+
+    // Add orphaned non-leaf files to deletion list
+    safeToDelete = [...safeToDelete, ...orphanedNonLeafFiles];
+
+    return safeToDelete;
+  }, []);
+
+  // Shared internal delete logic
+  const performFileDelete = useCallback(async (fileToRemove: StirlingFileStub, fileIndex: number) => {
+    const deletedFileId = fileToRemove.id;
+
+    // Get all stored files to analyze lineages
+    const allStoredStubs = await fileStorage.getAllStirlingFileStubs();
+
+    // Get safe files to delete (respecting shared lineages)
+    const filesToDelete = getSafeFilesToDelete([deletedFileId], allStoredStubs);
+
+    // Clear from selection immediately
+    setSelectedFileIds(prev => prev.filter(id => !filesToDelete.includes(id)));
+
+    // Clear from expanded state to prevent ghost entries
+    setExpandedFileIds(prev => {
+      const newExpanded = new Set(prev);
+      filesToDelete.forEach(id => newExpanded.delete(id));
+      return newExpanded;
+    });
+
+    // Clear from history cache - remove all files in the chain
+    setLoadedHistoryFiles(prev => {
+      const newCache = new Map(prev);
+
+      // Remove cache entries for all deleted files
+      filesToDelete.forEach(id => newCache.delete(id as FileId));
+
+      // Also remove deleted files from any other file's history cache
+      for (const [mainFileId, historyFiles] of newCache.entries()) {
+        const filteredHistory = historyFiles.filter(histFile => !filesToDelete.includes(histFile.id));
+        if (filteredHistory.length !== historyFiles.length) {
+          newCache.set(mainFileId, filteredHistory);
+        }
+      }
+
+      return newCache;
+    });
+
+    // Delete safe files from IndexedDB
+    try {
+      for (const fileId of filesToDelete) {
+        await fileStorage.deleteStirlingFile(fileId as FileId);
+      }
+    } catch (error) {
+      console.error('Failed to delete files from chain:', error);
+    }
+
+    // Call the parent's deletion logic for the main file only
+    onFileRemove(fileIndex);
+
+    // Refresh to ensure consistent state
+    await refreshRecentFiles();
+  }, [getSafeFilesToDelete, setSelectedFileIds, setExpandedFileIds, setLoadedHistoryFiles, onFileRemove, refreshRecentFiles]);
+
+  const handleFileRemove = useCallback(async (index: number) => {
     const fileToRemove = filteredFiles[index];
     if (fileToRemove) {
-      setSelectedFileIds(prev => prev.filter(id => id !== fileToRemove.id));
+      await performFileDelete(fileToRemove, index);
     }
-    onFileRemove(index);
-  }, [filteredFiles, onFileRemove]);
+  }, [filteredFiles, performFileDelete]);
 
-  const handleFileDoubleClick = useCallback((file: FileMetadata) => {
+  // Handle deletion by fileId (more robust than index-based)
+  const handleFileRemoveById = useCallback(async (fileId: FileId) => {
+    // Find the file and its index in filteredFiles
+    const fileIndex = filteredFiles.findIndex(file => file.id === fileId);
+    const fileToRemove = filteredFiles[fileIndex];
+
+    if (fileToRemove && fileIndex !== -1) {
+      await performFileDelete(fileToRemove, fileIndex);
+    }
+  }, [filteredFiles, performFileDelete]);
+
+  // Handle deletion of specific history files (not index-based)
+  const handleHistoryFileRemove = useCallback(async (fileToRemove: StirlingFileStub) => {
+    const deletedFileId = fileToRemove.id;
+
+    // Clear from expanded state to prevent ghost entries
+    setExpandedFileIds(prev => {
+      const newExpanded = new Set(prev);
+      newExpanded.delete(deletedFileId);
+      return newExpanded;
+    });
+
+    // Clear from history cache - remove all files in the chain
+    setLoadedHistoryFiles(prev => {
+      const newCache = new Map(prev);
+
+      // Remove cache entries for all deleted files
+      newCache.delete(deletedFileId);
+
+      // Also remove deleted files from any other file's history cache
+      for (const [mainFileId, historyFiles] of newCache.entries()) {
+        const filteredHistory = historyFiles.filter(histFile => deletedFileId != histFile.id);
+        if (filteredHistory.length !== historyFiles.length) {
+          newCache.set(mainFileId, filteredHistory);
+        }
+      }
+
+      return newCache;
+    });
+
+    // Delete safe files from IndexedDB
+    try {
+        await fileStorage.deleteStirlingFile(deletedFileId);
+    } catch (error) {
+      console.error('Failed to delete files from chain:', error);
+    }
+
+    // Refresh to ensure consistent state
+    await refreshRecentFiles();
+  }, [filteredFiles, onFileRemove, refreshRecentFiles, getSafeFilesToDelete]);
+
+  const handleFileDoubleClick = useCallback((file: StirlingFileStub) => {
     if (isFileSupported(file.name)) {
-      onFilesSelected([file]);
+      onRecentFilesSelected([file]);
       onClose();
     }
-  }, [isFileSupported, onFilesSelected, onClose]);
+  }, [isFileSupported, onRecentFilesSelected, onClose]);
 
   const handleOpenFiles = useCallback(() => {
     if (selectedFiles.length > 0) {
-      onFilesSelected(selectedFiles);
+      onRecentFilesSelected(selectedFiles);
       onClose();
     }
-  }, [selectedFiles, onFilesSelected, onClose]);
+  }, [selectedFiles, onRecentFilesSelected, onClose]);
 
   const handleSearchChange = useCallback((value: string) => {
     setSearchTerm(value);
@@ -196,25 +416,14 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     if (selectedFileIds.length === 0) return;
 
     try {
-      // Get files to delete based on current filtered view
-      const filesToDelete = filteredFiles.filter(file =>
-        selectedFileIds.includes(file.id)
-      );
-
-      // Delete files from storage
-      for (const file of filesToDelete) {
-        await fileStorage.deleteFile(file.id);
+      // Delete each selected file using the proven single delete logic
+      for (const fileId of selectedFileIds) {
+        await handleFileRemoveById(fileId);
       }
-
-      // Clear selection
-      setSelectedFileIds([]);
-
-      // Refresh the file list
-      await refreshRecentFiles();
     } catch (error) {
       console.error('Failed to delete selected files:', error);
     }
-  }, [selectedFileIds, filteredFiles, refreshRecentFiles]);
+  }, [selectedFileIds, handleFileRemoveById]);
 
 
   const handleDownloadSelected = useCallback(async () => {
@@ -235,7 +444,7 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     }
   }, [selectedFileIds, filteredFiles]);
 
-  const handleDownloadSingle = useCallback(async (file: FileMetadata) => {
+  const handleDownloadSingle = useCallback(async (file: StirlingFileStub) => {
     try {
       await downloadFiles([file]);
     } catch (error) {
@@ -243,6 +452,94 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     }
   }, []);
 
+  const handleToggleExpansion = useCallback(async (fileId: FileId) => {
+    const isCurrentlyExpanded = expandedFileIds.has(fileId);
+
+    // Update expansion state
+    setExpandedFileIds(prev => {
+      const newSet = new Set(prev);
+      if (newSet.has(fileId)) {
+        newSet.delete(fileId);
+      } else {
+        newSet.add(fileId);
+      }
+      return newSet;
+    });
+
+    // Load complete history chain if expanding
+    if (!isCurrentlyExpanded) {
+      const currentFileMetadata = recentFiles.find(f => f.id === fileId);
+      if (currentFileMetadata && (currentFileMetadata.versionNumber || 1) > 1) {
+        try {
+          // Get all stored file metadata for chain traversal
+          const allStoredStubs = await fileStorage.getAllStirlingFileStubs();
+          const fileMap = new Map(allStoredStubs.map(f => [f.id, f]));
+
+          // Get the current file's IndexedDB data
+          const currentStoredStub = fileMap.get(fileId as FileId);
+          if (!currentStoredStub) {
+            console.warn(`No stored file found for ${fileId}`);
+            return;
+          }
+
+          // Build complete history chain using IndexedDB metadata
+          const historyFiles: StirlingFileStub[] = [];
+
+          // Find the original file
+
+          // Collect only files in this specific branch (ancestors of current file)
+          const chainFiles: StirlingFileStub[] = [];
+          const allFiles = Array.from(fileMap.values());
+
+          // Build a map for fast parent lookups
+          const fileIdMap = new Map<FileId, StirlingFileStub>();
+          allFiles.forEach(f => fileIdMap.set(f.id, f));
+
+          // Trace back from current file through parent chain
+          let currentFile = fileIdMap.get(fileId);
+          while (currentFile?.parentFileId) {
+            const parentFile = fileIdMap.get(currentFile.parentFileId);
+            if (parentFile) {
+              chainFiles.push(parentFile);
+              currentFile = parentFile;
+            } else {
+              break; // Parent not found, stop tracing
+            }
+          }
+
+          // Sort by version number (oldest first for history display)
+          chainFiles.sort((a, b) => (a.versionNumber || 1) - (b.versionNumber || 1));
+
+          // StirlingFileStubs already have all the data we need - no conversion required!
+          historyFiles.push(...chainFiles);
+
+          // Cache the loaded history files
+          setLoadedHistoryFiles(prev => new Map(prev.set(fileId as FileId, historyFiles)));
+        } catch (error) {
+          console.warn(`Failed to load history chain for file ${fileId}:`, error);
+        }
+      }
+    } else {
+      // Clear loaded history when collapsing
+      setLoadedHistoryFiles(prev => {
+        const newMap = new Map(prev);
+        newMap.delete(fileId as FileId);
+        return newMap;
+      });
+    }
+  }, [expandedFileIds, recentFiles]);
+
+  const handleAddToRecents = useCallback(async (file: StirlingFileStub) => {
+    try {
+      // Mark the file as a leaf node so it appears in recent files
+      await fileStorage.markFileAsLeaf(file.id);
+
+      // Refresh the recent files list to show updated state
+      await refreshRecentFiles();
+    } catch (error) {
+      console.error('Failed to add to recents:', error);
+    }
+  }, [refreshRecentFiles]);
 
   // Cleanup blob URLs when component unmounts
   useEffect(() => {
@@ -274,12 +571,16 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     filteredFiles,
     fileInputRef,
     selectedFilesSet,
+    expandedFileIds,
+    fileGroups,
+    loadedHistoryFiles,
 
     // Handlers
     onSourceChange: handleSourceChange,
     onLocalFileClick: handleLocalFileClick,
     onFileSelect: handleFileSelect,
     onFileRemove: handleFileRemove,
+    onHistoryFileRemove: handleHistoryFileRemove,
     onFileDoubleClick: handleFileDoubleClick,
     onOpenFiles: handleOpenFiles,
     onSearchChange: handleSearchChange,
@@ -288,6 +589,9 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     onDeleteSelected: handleDeleteSelected,
     onDownloadSelected: handleDownloadSelected,
     onDownloadSingle: handleDownloadSingle,
+    onToggleExpansion: handleToggleExpansion,
+    onAddToRecents: handleAddToRecents,
+    onNewFilesSelect,
 
     // External props
     recentFiles,
@@ -300,10 +604,15 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     selectedFiles,
     filteredFiles,
     fileInputRef,
+    expandedFileIds,
+    fileGroups,
+    loadedHistoryFiles,
     handleSourceChange,
     handleLocalFileClick,
     handleFileSelect,
     handleFileRemove,
+    handleFileRemoveById,
+    performFileDelete,
     handleFileDoubleClick,
     handleOpenFiles,
     handleSearchChange,
@@ -311,6 +620,9 @@ export const FileManagerProvider: React.FC<FileManagerProviderProps> = ({
     handleSelectAll,
     handleDeleteSelected,
     handleDownloadSelected,
+    handleToggleExpansion,
+    handleAddToRecents,
+    onNewFilesSelect,
     recentFiles,
     isFileSupported,
     modalHeight,

frontend/src/contexts/FilesModalContext.tsx

@@ -1,15 +1,15 @@
 import React, { createContext, useContext, useState, useCallback, useMemo } from 'react';
 import { useFileHandler } from '../hooks/useFileHandler';
-import { FileMetadata } from '../types/file';
-import { FileId } from '../types/file';
+import { useFileActions } from './FileContext';
+import { StirlingFileStub } from '../types/fileContext';
+import { fileStorage } from '../services/fileStorage';
 
 interface FilesModalContextType {
   isFilesModalOpen: boolean;
   openFilesModal: (options?: { insertAfterPage?: number; customHandler?: (files: File[], insertAfterPage?: number) => void }) => void;
   closeFilesModal: () => void;
-  onFileSelect: (file: File) => void;
-  onFilesSelect: (files: File[]) => void;
-  onStoredFilesSelect: (filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>) => void;
+  onFileUpload: (files: File[]) => void;
+  onRecentFileSelect: (stirlingFileStubs: StirlingFileStub[]) => void;
   onModalClose?: () => void;
   setOnModalClose: (callback: () => void) => void;
 }
@@ -17,7 +17,8 @@ interface FilesModalContextType {
 const FilesModalContext = createContext<FilesModalContextType | null>(null);
 
 export const FilesModalProvider: React.FC<{ children: React.ReactNode }> = ({ children }) => {
-  const { addToActiveFiles, addMultipleFiles, addStoredFiles } = useFileHandler();
+  const { addFiles } = useFileHandler();
+  const { actions } = useFileActions();
   const [isFilesModalOpen, setIsFilesModalOpen] = useState(false);
   const [onModalClose, setOnModalClose] = useState<(() => void) | undefined>();
   const [insertAfterPage, setInsertAfterPage] = useState<number | undefined>();
@@ -36,39 +37,45 @@ export const FilesModalProvider: React.FC<{ children: React.ReactNode }> = ({ ch
     onModalClose?.();
   }, [onModalClose]);
 
-  const handleFileSelect = useCallback((file: File) => {
-    if (customHandler) {
-      // Use custom handler for special cases (like page insertion)
-      customHandler([file], insertAfterPage);
-    } else {
-      // Use normal file handling
-      addToActiveFiles(file);
-    }
-    closeFilesModal();
-  }, [addToActiveFiles, closeFilesModal, insertAfterPage, customHandler]);
-
-  const handleFilesSelect = useCallback((files: File[]) => {
+  const handleFileUpload = useCallback((files: File[]) => {
     if (customHandler) {
       // Use custom handler for special cases (like page insertion)
       customHandler(files, insertAfterPage);
     } else {
       // Use normal file handling
-      addMultipleFiles(files);
+      addFiles(files);
     }
     closeFilesModal();
-  }, [addMultipleFiles, closeFilesModal, insertAfterPage, customHandler]);
+  }, [addFiles, closeFilesModal, insertAfterPage, customHandler]);
 
-  const handleStoredFilesSelect = useCallback((filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>) => {
+  const handleRecentFileSelect = useCallback(async (stirlingFileStubs: StirlingFileStub[]) => {
     if (customHandler) {
-      // Use custom handler for special cases (like page insertion)
-      const files = filesWithMetadata.map(item => item.file);
-      customHandler(files, insertAfterPage);
+      // Load the actual files from storage for custom handler
+      try {
+        const loadedFiles: File[] = [];
+        for (const stub of stirlingFileStubs) {
+          const stirlingFile = await fileStorage.getStirlingFile(stub.id);
+          if (stirlingFile) {
+            loadedFiles.push(stirlingFile);
+          }
+        }
+        
+        if (loadedFiles.length > 0) {
+          customHandler(loadedFiles, insertAfterPage);
+        }
+      } catch (error) {
+        console.error('Failed to load files for custom handler:', error);
+      }
     } else {
-      // Use normal file handling
-      addStoredFiles(filesWithMetadata);
+      // Normal case - use addStirlingFileStubs to preserve metadata
+      if (actions.addStirlingFileStubs) {
+        actions.addStirlingFileStubs(stirlingFileStubs, { selectFiles: true });
+      } else {
+        console.error('addStirlingFileStubs action not available');
+      }
     }
     closeFilesModal();
-  }, [addStoredFiles, closeFilesModal, insertAfterPage, customHandler]);
+  }, [actions.addStirlingFileStubs, closeFilesModal, customHandler, insertAfterPage]);
 
   const setModalCloseCallback = useCallback((callback: () => void) => {
     setOnModalClose(() => callback);
@@ -78,18 +85,16 @@ export const FilesModalProvider: React.FC<{ children: React.ReactNode }> = ({ ch
     isFilesModalOpen,
     openFilesModal,
     closeFilesModal,
-    onFileSelect: handleFileSelect,
-    onFilesSelect: handleFilesSelect,
-    onStoredFilesSelect: handleStoredFilesSelect,
+    onFileUpload: handleFileUpload,
+    onRecentFileSelect: handleRecentFileSelect,
     onModalClose,
     setOnModalClose: setModalCloseCallback,
   }), [
     isFilesModalOpen,
     openFilesModal,
     closeFilesModal,
-    handleFileSelect,
-    handleFilesSelect,
-    handleStoredFilesSelect,
+    handleFileUpload,
+    handleRecentFileSelect,
     onModalClose,
     setModalCloseCallback,
   ]);

frontend/src/contexts/IndexedDBContext.tsx

@@ -4,28 +4,30 @@
  */
 
 import React, { createContext, useContext, useCallback, useRef } from 'react';
-
-const DEBUG = process.env.NODE_ENV === 'development';
 import { fileStorage } from '../services/fileStorage';
 import { FileId } from '../types/file';
-import { FileMetadata } from '../types/file';
+import { StirlingFileStub, createStirlingFile, createQuickKey } from '../types/fileContext';
 import { generateThumbnailForFile } from '../utils/thumbnailUtils';
 
+const DEBUG = process.env.NODE_ENV === 'development';
+
 interface IndexedDBContextValue {
   // Core CRUD operations
-  saveFile: (file: File, fileId: FileId, existingThumbnail?: string) => Promise<FileMetadata>;
+  saveFile: (file: File, fileId: FileId, existingThumbnail?: string) => Promise<StirlingFileStub>;
   loadFile: (fileId: FileId) => Promise<File | null>;
-  loadMetadata: (fileId: FileId) => Promise<FileMetadata | null>;
+  loadMetadata: (fileId: FileId) => Promise<StirlingFileStub | null>;
   deleteFile: (fileId: FileId) => Promise<void>;
 
   // Batch operations
-  loadAllMetadata: () => Promise<FileMetadata[]>;
+  loadAllMetadata: () => Promise<StirlingFileStub[]>;
+  loadLeafMetadata: () => Promise<StirlingFileStub[]>; // Only leaf files for recent files list
   deleteMultiple: (fileIds: FileId[]) => Promise<void>;
   clearAll: () => Promise<void>;
 
   // Utilities
   getStorageStats: () => Promise<{ used: number; available: number; fileCount: number }>;
   updateThumbnail: (fileId: FileId, thumbnail: string) => Promise<boolean>;
+  markFileAsProcessed: (fileId: FileId) => Promise<boolean>;
 }
 
 const IndexedDBContext = createContext<IndexedDBContextValue | null>(null);
@@ -56,26 +58,42 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     if (DEBUG) console.log(`🗂️ Evicted ${toRemove.length} LRU cache entries`);
   }, []);
 
-  const saveFile = useCallback(async (file: File, fileId: FileId, existingThumbnail?: string): Promise<FileMetadata> => {
+  const saveFile = useCallback(async (file: File, fileId: FileId, existingThumbnail?: string): Promise<StirlingFileStub> => {
     // Use existing thumbnail or generate new one if none provided
     const thumbnail = existingThumbnail || await generateThumbnailForFile(file);
 
-    // Store in IndexedDB
-    await fileStorage.storeFile(file, fileId, thumbnail);
+    // Store in IndexedDB (no history data - that's handled by direct fileStorage calls now)
+    const stirlingFile = createStirlingFile(file, fileId);
+
+    // Create minimal stub for storage
+    const stub: StirlingFileStub = {
+      id: fileId,
+      name: file.name,
+      size: file.size,
+      type: file.type,
+      lastModified: file.lastModified,
+      quickKey: createQuickKey(file),
+      thumbnailUrl: thumbnail,
+      isLeaf: true,
+      createdAt: Date.now(),
+      versionNumber: 1,
+      originalFileId: fileId,
+      toolHistory: []
+    };
+
+    await fileStorage.storeStirlingFile(stirlingFile, stub);
+    const storedFile = await fileStorage.getStirlingFileStub(fileId);
 
     // Cache the file object for immediate reuse
     fileCache.current.set(fileId, { file, lastAccessed: Date.now() });
     evictLRUEntries();
 
-    // Return metadata
-    return {
-      id: fileId,
-      name: file.name,
-      type: file.type,
-      size: file.size,
-      lastModified: file.lastModified,
-      thumbnail
-    };
+    // Return StirlingFileStub from the stored file (no conversion needed)
+    if (!storedFile) {
+      throw new Error(`Failed to retrieve stored file after saving: ${file.name}`);
+    }
+
+    return storedFile;
   }, []);
 
   const loadFile = useCallback(async (fileId: FileId): Promise<File | null> => {
@@ -88,14 +106,11 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     }
 
     // Load from IndexedDB
-    const storedFile = await fileStorage.getFile(fileId);
+    const storedFile = await fileStorage.getStirlingFile(fileId);
     if (!storedFile) return null;
 
-    // Reconstruct File object
-    const file = new File([storedFile.data], storedFile.name, {
-      type: storedFile.type,
-      lastModified: storedFile.lastModified
-    });
+    // StirlingFile is already a File object, no reconstruction needed
+    const file = storedFile;
 
     // Cache for future use with LRU eviction
     fileCache.current.set(fileId, { file, lastAccessed: Date.now() });
@@ -104,34 +119,9 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     return file;
   }, [evictLRUEntries]);
 
-  const loadMetadata = useCallback(async (fileId: FileId): Promise<FileMetadata | null> => {
-    // Try to get from cache first (no IndexedDB hit)
-    const cached = fileCache.current.get(fileId);
-    if (cached) {
-      const file = cached.file;
-      return {
-        id: fileId,
-        name: file.name,
-        type: file.type,
-        size: file.size,
-        lastModified: file.lastModified
-      };
-    }
-
-    // Load metadata from IndexedDB (efficient - no data field)
-    const metadata = await fileStorage.getAllFileMetadata();
-    const fileMetadata = metadata.find(m => m.id === fileId);
-
-    if (!fileMetadata) return null;
-
-    return {
-      id: fileMetadata.id,
-      name: fileMetadata.name,
-      type: fileMetadata.type,
-      size: fileMetadata.size,
-      lastModified: fileMetadata.lastModified,
-      thumbnail: fileMetadata.thumbnail
-    };
+  const loadMetadata = useCallback(async (fileId: FileId): Promise<StirlingFileStub | null> => {
+    // Load stub directly from storage service
+    return await fileStorage.getStirlingFileStub(fileId);
   }, []);
 
   const deleteFile = useCallback(async (fileId: FileId): Promise<void> => {
@@ -139,20 +129,22 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     fileCache.current.delete(fileId);
 
     // Remove from IndexedDB
-    await fileStorage.deleteFile(fileId);
+    await fileStorage.deleteStirlingFile(fileId);
   }, []);
 
-  const loadAllMetadata = useCallback(async (): Promise<FileMetadata[]> => {
-    const metadata = await fileStorage.getAllFileMetadata();
+  const loadLeafMetadata = useCallback(async (): Promise<StirlingFileStub[]> => {
+    const metadata = await fileStorage.getLeafStirlingFileStubs(); // Only get leaf files
 
-    return metadata.map(m => ({
-      id: m.id,
-      name: m.name,
-      type: m.type,
-      size: m.size,
-      lastModified: m.lastModified,
-      thumbnail: m.thumbnail
-    }));
+    // All files are already StirlingFileStub objects, no processing needed
+    return metadata;
+
+  }, []);
+
+  const loadAllMetadata = useCallback(async (): Promise<StirlingFileStub[]> => {
+    const metadata = await fileStorage.getAllStirlingFileStubs();
+
+    // All files are already StirlingFileStub objects, no processing needed
+    return metadata;
   }, []);
 
   const deleteMultiple = useCallback(async (fileIds: FileId[]): Promise<void> => {
@@ -160,7 +152,7 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     fileIds.forEach(id => fileCache.current.delete(id));
 
     // Remove from IndexedDB in parallel
-    await Promise.all(fileIds.map(id => fileStorage.deleteFile(id)));
+    await Promise.all(fileIds.map(id => fileStorage.deleteStirlingFile(id)));
   }, []);
 
   const clearAll = useCallback(async (): Promise<void> => {
@@ -179,16 +171,22 @@ export function IndexedDBProvider({ children }: IndexedDBProviderProps) {
     return await fileStorage.updateThumbnail(fileId, thumbnail);
   }, []);
 
+  const markFileAsProcessed = useCallback(async (fileId: FileId): Promise<boolean> => {
+    return await fileStorage.markFileAsProcessed(fileId);
+  }, []);
+
   const value: IndexedDBContextValue = {
     saveFile,
     loadFile,
     loadMetadata,
     deleteFile,
     loadAllMetadata,
+    loadLeafMetadata,
     deleteMultiple,
     clearAll,
     getStorageStats,
-    updateThumbnail
+    updateThumbnail,
+    markFileAsProcessed
   };
 
   return (

frontend/src/contexts/file/FileReducer.ts

@@ -125,16 +125,18 @@ export function fileContextReducer(state: FileContextState, action: FileContextA
         return state; // File doesn't exist, no-op
       }
 
+      const updatedRecord = {
+        ...existingRecord,
+        ...updates
+      };
+
       return {
         ...state,
         files: {
           ...state.files,
           byId: {
             ...state.files.byId,
-            [id]: {
-              ...existingRecord,
-              ...updates
-            }
+            [id]: updatedRecord
           }
         }
       };

frontend/src/contexts/file/fileActions.ts

@@ -6,15 +6,18 @@ import {
   StirlingFileStub,
   FileContextAction,
   FileContextState,
-  toStirlingFileStub,
+  createNewStirlingFileStub,
   createFileId,
-  createQuickKey
+  createQuickKey,
+  createStirlingFile,
+  ProcessedFileMetadata,
 } from '../../types/fileContext';
-import { FileId, FileMetadata } from '../../types/file';
+import { FileId } from '../../types/file';
 import { generateThumbnailWithMetadata } from '../../utils/thumbnailUtils';
 import { FileLifecycleManager } from './lifecycle';
 import { buildQuickKeySet } from './fileSelectors';
-
+import { StirlingFile } from '../../types/fileContext';
+import { fileStorage } from '../../services/fileStorage';
 const DEBUG = process.env.NODE_ENV === 'development';
 
 /**
@@ -69,345 +72,283 @@ export function createProcessedFile(pageCount: number, thumbnail?: string) {
 }
 
 /**
- * File addition types
+ * Generate fresh ProcessedFileMetadata for a file
+ * Used when tools process files to ensure metadata matches actual file content
  */
-type AddFileKind = 'raw' | 'processed' | 'stored';
+export async function generateProcessedFileMetadata(file: File): Promise<ProcessedFileMetadata | undefined> {
+  // Only generate metadata for PDF files
+  if (!file.type.startsWith('application/pdf')) {
+    return undefined;
+  }
+
+  try {
+    const result = await generateThumbnailWithMetadata(file);
+      return createProcessedFile(result.pageCount, result.thumbnail);
+  } catch (error) {
+    if (DEBUG) console.warn(`📄 Failed to generate processedFileMetadata for ${file.name}:`, error);
+  }
+
+  return undefined;
+}
+
+/**
+ * Create a child StirlingFileStub from a parent stub with proper history management.
+ * Used when a tool processes an existing file to create a new version with incremented history.
+ *
+ * @param parentStub - The parent StirlingFileStub to create a child from
+ * @param operation - Tool operation information (toolName, timestamp)
+ * @param resultingFile - The processed File object
+ * @param thumbnail - Optional thumbnail for the child
+ * @param processedFileMetadata - Optional fresh metadata for the processed file
+ * @returns New child StirlingFileStub with proper version history
+ */
+export function createChildStub(
+  parentStub: StirlingFileStub,
+  operation: { toolName: string; timestamp: number },
+  resultingFile: File,
+  thumbnail?: string,
+  processedFileMetadata?: ProcessedFileMetadata
+): StirlingFileStub {
+  const newFileId = createFileId();
+
+  // Build new tool history by appending to parent's history
+  const parentToolHistory = parentStub.toolHistory || [];
+  const newToolHistory = [...parentToolHistory, operation];
+
+  // Calculate new version number
+  const newVersionNumber = (parentStub.versionNumber || 1) + 1;
+
+  // Determine original file ID (root of the version chain)
+  const originalFileId = parentStub.originalFileId || parentStub.id;
+
+  // Copy parent metadata but exclude processedFile to prevent stale data
+  const { processedFile: _processedFile, ...parentMetadata } = parentStub;
+
+  return {
+    // Copy parent metadata (excluding processedFile)
+    ...parentMetadata,
+
+    // Update identity and version info
+    id: newFileId,
+    versionNumber: newVersionNumber,
+    parentFileId: parentStub.id,
+    originalFileId: originalFileId,
+    toolHistory: newToolHistory,
+    createdAt: Date.now(),
+    isLeaf: true, // New child is the current leaf node
+    name: resultingFile.name,
+    size: resultingFile.size,
+    type: resultingFile.type,
+    lastModified: resultingFile.lastModified,
+    thumbnailUrl: thumbnail,
+
+    // Set fresh processedFile metadata (no inheritance from parent)
+    processedFile: processedFileMetadata
+  };
+}
 
 interface AddFileOptions {
-  // For 'raw' files
   files?: File[];
 
   // For 'processed' files
   filesWithThumbnails?: Array<{ file: File; thumbnail?: string; pageCount?: number }>;
 
-  // For 'stored' files
-  filesWithMetadata?: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>;
-
   // Insertion position
   insertAfterPageId?: string;
-}
 
-export interface AddedFile {
-  file: File;
-  id: FileId;
-  thumbnail?: string;
+  // Auto-selection after adding
+  selectFiles?: boolean;
 }
 
 /**
- * Unified file addition helper - replaces addFiles/addProcessedFiles/addStoredFiles
+ * Unified file addition helper - replaces addFiles
  */
 export async function addFiles(
-  kind: AddFileKind,
   options: AddFileOptions,
   stateRef: React.MutableRefObject<FileContextState>,
   filesRef: React.MutableRefObject<Map<FileId, File>>,
   dispatch: React.Dispatch<FileContextAction>,
-  lifecycleManager: FileLifecycleManager
-): Promise<AddedFile[]> {
+  lifecycleManager: FileLifecycleManager,
+  enablePersistence: boolean = false
+): Promise<StirlingFile[]> {
   // Acquire mutex to prevent race conditions
   await addFilesMutex.lock();
 
   try {
     const stirlingFileStubs: StirlingFileStub[] = [];
-    const addedFiles: AddedFile[] = [];
+    const stirlingFiles: StirlingFile[] = [];
 
   // Build quickKey lookup from existing files for deduplication
   const existingQuickKeys = buildQuickKeySet(stateRef.current.files.byId);
-  if (DEBUG) console.log(`📄 addFiles(${kind}): Existing quickKeys for deduplication:`, Array.from(existingQuickKeys));
 
-  switch (kind) {
-    case 'raw': {
-      const { files = [] } = options;
-      if (DEBUG) console.log(`📄 addFiles(raw): Adding ${files.length} files with immediate thumbnail generation`);
+  const { files = [] } = options;
+  if (DEBUG) console.log(`📄 addFiles(raw): Adding ${files.length} files with immediate thumbnail generation`);
 
-      for (const file of files) {
-        const quickKey = createQuickKey(file);
+  for (const file of files) {
+    const quickKey = createQuickKey(file);
 
-        // Soft deduplication: Check if file already exists by metadata
-        if (existingQuickKeys.has(quickKey)) {
-          if (DEBUG) console.log(`📄 Skipping duplicate file: ${file.name} (quickKey: ${quickKey})`);
-          continue;
-        }
-        if (DEBUG) console.log(`📄 Adding new file: ${file.name} (quickKey: ${quickKey})`);
-
-        const fileId = createFileId();
-        filesRef.current.set(fileId, file);
-
-        // Generate thumbnail and page count immediately
-        let thumbnail: string | undefined;
-        let pageCount: number = 1;
-
-        // Route based on file type - PDFs through full metadata pipeline, non-PDFs through simple path
-        if (file.type.startsWith('application/pdf')) {
-          try {
-            if (DEBUG) console.log(`📄 Generating PDF metadata for ${file.name}`);
-            const result = await generateThumbnailWithMetadata(file);
-            thumbnail = result.thumbnail;
-            pageCount = result.pageCount;
-            if (DEBUG) console.log(`📄 Generated PDF metadata for ${file.name}: ${pageCount} pages, thumbnail: SUCCESS`);
-          } catch (error) {
-            if (DEBUG) console.warn(`📄 Failed to generate PDF metadata for ${file.name}:`, error);
-          }
-        } else {
-          // Non-PDF files: simple thumbnail generation, no page count
-          try {
-            if (DEBUG) console.log(`📄 Generating simple thumbnail for non-PDF file ${file.name}`);
-            const { generateThumbnailForFile } = await import('../../utils/thumbnailUtils');
-            thumbnail = await generateThumbnailForFile(file);
-            pageCount = 0; // Non-PDFs have no page count
-            if (DEBUG) console.log(`📄 Generated simple thumbnail for ${file.name}: no page count, thumbnail: SUCCESS`);
-          } catch (error) {
-            if (DEBUG) console.warn(`📄 Failed to generate simple thumbnail for ${file.name}:`, error);
-          }
-        }
-
-        // Create record with immediate thumbnail and page metadata
-        const record = toStirlingFileStub(file, fileId);
-        if (thumbnail) {
-          record.thumbnailUrl = thumbnail;
-          // Track blob URLs for cleanup (images return blob URLs that need revocation)
-          if (thumbnail.startsWith('blob:')) {
-            lifecycleManager.trackBlobUrl(thumbnail);
-          }
-        }
-
-        // Store insertion position if provided
-        if (options.insertAfterPageId !== undefined) {
-          record.insertAfterPageId = options.insertAfterPageId;
-        }
-
-        // Create initial processedFile metadata with page count
-        if (pageCount > 0) {
-          record.processedFile = createProcessedFile(pageCount, thumbnail);
-          if (DEBUG) console.log(`📄 addFiles(raw): Created initial processedFile metadata for ${file.name} with ${pageCount} pages`);
-        }
-
-        existingQuickKeys.add(quickKey);
-        stirlingFileStubs.push(record);
-        addedFiles.push({ file, id: fileId, thumbnail });
-        }
-      break;
+    // Soft deduplication: Check if file already exists by metadata
+    if (existingQuickKeys.has(quickKey)) {
+      if (DEBUG) console.log(`📄 Skipping duplicate file: ${file.name} (quickKey: ${quickKey})`);
+      continue;
     }
+    if (DEBUG) console.log(`📄 Adding new file: ${file.name} (quickKey: ${quickKey})`);
 
-    case 'processed': {
-      const { filesWithThumbnails = [] } = options;
-      if (DEBUG) console.log(`📄 addFiles(processed): Adding ${filesWithThumbnails.length} processed files with pre-existing thumbnails`);
+    const fileId = createFileId();
+    filesRef.current.set(fileId, file);
 
-      for (const { file, thumbnail, pageCount = 1 } of filesWithThumbnails) {
-        const quickKey = createQuickKey(file);
+    // Generate processedFile metadata using centralized function
+    const processedFileMetadata = await generateProcessedFileMetadata(file);
 
-        if (existingQuickKeys.has(quickKey)) {
-          if (DEBUG) console.log(`📄 Skipping duplicate processed file: ${file.name}`);
-          continue;
-        }
-
-        const fileId = createFileId();
-        filesRef.current.set(fileId, file);
-
-        const record = toStirlingFileStub(file, fileId);
-        if (thumbnail) {
-          record.thumbnailUrl = thumbnail;
-          // Track blob URLs for cleanup (images return blob URLs that need revocation)
-          if (thumbnail.startsWith('blob:')) {
-            lifecycleManager.trackBlobUrl(thumbnail);
-          }
-        }
-
-        // Store insertion position if provided
-        if (options.insertAfterPageId !== undefined) {
-          record.insertAfterPageId = options.insertAfterPageId;
-        }
-
-        // Create processedFile with provided metadata
-        if (pageCount > 0) {
-          record.processedFile = createProcessedFile(pageCount, thumbnail);
-          if (DEBUG) console.log(`📄 addFiles(processed): Created initial processedFile metadata for ${file.name} with ${pageCount} pages`);
-        }
-
-        existingQuickKeys.add(quickKey);
-        stirlingFileStubs.push(record);
-        addedFiles.push({ file, id: fileId, thumbnail });
+    // Extract thumbnail for non-PDF files or use from processedFile for PDFs
+    let thumbnail: string | undefined;
+    if (processedFileMetadata) {
+      // PDF file - use thumbnail from processedFile metadata
+      thumbnail = processedFileMetadata.thumbnailUrl;
+      if (DEBUG) console.log(`📄 Generated PDF metadata for ${file.name}: ${processedFileMetadata.totalPages} pages, thumbnail: SUCCESS`);
+    } else if (!file.type.startsWith('application/pdf')) {
+      // Non-PDF files: simple thumbnail generation, no processedFile metadata
+      try {
+        if (DEBUG) console.log(`📄 Generating simple thumbnail for non-PDF file ${file.name}`);
+        const { generateThumbnailForFile } = await import('../../utils/thumbnailUtils');
+        thumbnail = await generateThumbnailForFile(file);
+        if (DEBUG) console.log(`📄 Generated simple thumbnail for ${file.name}: no page count, thumbnail: SUCCESS`);
+      } catch (error) {
+        if (DEBUG) console.warn(`📄 Failed to generate simple thumbnail for ${file.name}:`, error);
       }
-      break;
     }
 
-    case 'stored': {
-      const { filesWithMetadata = [] } = options;
-      if (DEBUG) console.log(`📄 addFiles(stored): Restoring ${filesWithMetadata.length} files from storage with existing metadata`);
-
-      for (const { file, originalId, metadata } of filesWithMetadata) {
-        const quickKey = createQuickKey(file);
-
-        if (existingQuickKeys.has(quickKey)) {
-          if (DEBUG) console.log(`📄 Skipping duplicate stored file: ${file.name} (quickKey: ${quickKey})`);
-          continue;
-        }
-        if (DEBUG) console.log(`📄 Adding stored file: ${file.name} (quickKey: ${quickKey})`);
-
-        // Try to preserve original ID, but generate new if it conflicts
-        let fileId = originalId;
-        if (filesRef.current.has(originalId)) {
-          fileId = createFileId();
-          if (DEBUG) console.log(`📄 ID conflict for stored file ${file.name}, using new ID: ${fileId}`);
-        }
-
-        filesRef.current.set(fileId, file);
-
-        const record = toStirlingFileStub(file, fileId);
-
-        // Generate processedFile metadata for stored files
-        let pageCount: number = 1;
-
-        // Only process PDFs through PDF worker manager, non-PDFs have no page count
-        if (file.type.startsWith('application/pdf')) {
-          try {
-            if (DEBUG) console.log(`📄 addFiles(stored): Generating PDF metadata for stored file ${file.name}`);
-
-            // Get page count from PDF
-            const arrayBuffer = await file.arrayBuffer();
-            const { pdfWorkerManager } = await import('../../services/pdfWorkerManager');
-            const pdf = await pdfWorkerManager.createDocument(arrayBuffer);
-            pageCount = pdf.numPages;
-            pdfWorkerManager.destroyDocument(pdf);
-
-            if (DEBUG) console.log(`📄 addFiles(stored): Found ${pageCount} pages in PDF ${file.name}`);
-          } catch (error) {
-            if (DEBUG) console.warn(`📄 addFiles(stored): Failed to generate PDF metadata for ${file.name}:`, error);
-          }
-        } else {
-          pageCount = 0; // Non-PDFs have no page count
-          if (DEBUG) console.log(`📄 addFiles(stored): Non-PDF file ${file.name}, no page count`);
-        }
-
-        // Restore metadata from storage
-        if (metadata.thumbnail) {
-          record.thumbnailUrl = metadata.thumbnail;
-          // Track blob URLs for cleanup (images return blob URLs that need revocation)
-          if (metadata.thumbnail.startsWith('blob:')) {
-            lifecycleManager.trackBlobUrl(metadata.thumbnail);
-          }
-        }
-
-        // Store insertion position if provided
-        if (options.insertAfterPageId !== undefined) {
-          record.insertAfterPageId = options.insertAfterPageId;
-        }
-
-        // Create processedFile metadata with correct page count
-        if (pageCount > 0) {
-          record.processedFile = createProcessedFile(pageCount, metadata.thumbnail);
-          if (DEBUG) console.log(`📄 addFiles(stored): Created processedFile metadata for ${file.name} with ${pageCount} pages`);
-        }
-
-        existingQuickKeys.add(quickKey);
-        stirlingFileStubs.push(record);
-        addedFiles.push({ file, id: fileId, thumbnail: metadata.thumbnail });
-
+    // Create new filestub with processedFile metadata
+    const fileStub = createNewStirlingFileStub(file, fileId, thumbnail, processedFileMetadata);
+    if (thumbnail) {
+      // Track blob URLs for cleanup (images return blob URLs that need revocation)
+      if (thumbnail.startsWith('blob:')) {
+        lifecycleManager.trackBlobUrl(thumbnail);
       }
-      break;
     }
+
+    // Store insertion position if provided
+    if (options.insertAfterPageId !== undefined) {
+      fileStub.insertAfterPageId = options.insertAfterPageId;
+    }
+
+    existingQuickKeys.add(quickKey);
+    stirlingFileStubs.push(fileStub);
+
+    // Create StirlingFile directly
+    const stirlingFile = createStirlingFile(file, fileId);
+    stirlingFiles.push(stirlingFile);
+  }
+
+  // Persist to storage if enabled using fileStorage service
+  if (enablePersistence && stirlingFiles.length > 0) {
+    await Promise.all(stirlingFiles.map(async (stirlingFile, index) => {
+      try {
+        // Get corresponding stub with all metadata
+        const fileStub = stirlingFileStubs[index];
+
+        // Store using the cleaner signature - pass StirlingFile + StirlingFileStub directly
+        await fileStorage.storeStirlingFile(stirlingFile, fileStub);
+
+        if (DEBUG) console.log(`📄 addFiles: Stored file ${stirlingFile.name} with metadata:`, fileStub);
+      } catch (error) {
+        console.error('Failed to persist file to storage:', stirlingFile.name, error);
+      }
+    }));
   }
 
   // Dispatch ADD_FILES action if we have new files
   if (stirlingFileStubs.length > 0) {
     dispatch({ type: 'ADD_FILES', payload: { stirlingFileStubs } });
-    if (DEBUG) console.log(`📄 addFiles(${kind}): Successfully added ${stirlingFileStubs.length} files`);
   }
 
-  return addedFiles;
+  return stirlingFiles;
   } finally {
     // Always release mutex even if error occurs
     addFilesMutex.unlock();
   }
 }
 
-/**
- * Helper function to process files into records with thumbnails and metadata
- */
-async function processFilesIntoRecords(
-  files: File[],
-  filesRef: React.MutableRefObject<Map<FileId, File>>
-): Promise<Array<{ record: StirlingFileStub; file: File; fileId: FileId; thumbnail?: string }>> {
-  return Promise.all(
-    files.map(async (file) => {
-      const fileId = createFileId();
-      filesRef.current.set(fileId, file);
-
-      // Generate thumbnail and page count
-      let thumbnail: string | undefined;
-      let pageCount: number = 1;
-
-      try {
-        if (DEBUG) console.log(`📄 Generating thumbnail for file ${file.name}`);
-        const result = await generateThumbnailWithMetadata(file);
-        thumbnail = result.thumbnail;
-        pageCount = result.pageCount;
-      } catch (error) {
-        if (DEBUG) console.warn(`📄 Failed to generate thumbnail for file ${file.name}:`, error);
-      }
-
-      const record = toStirlingFileStub(file, fileId);
-      if (thumbnail) {
-        record.thumbnailUrl = thumbnail;
-      }
-
-      if (pageCount > 0) {
-        record.processedFile = createProcessedFile(pageCount, thumbnail);
-      }
-
-      return { record, file, fileId, thumbnail };
-    })
-  );
-}
-
-/**
- * Helper function to persist files to IndexedDB
- */
-async function persistFilesToIndexedDB(
-  stirlingFileStubs: Array<{ file: File; fileId: FileId; thumbnail?: string }>,
-  indexedDB: { saveFile: (file: File, fileId: FileId, existingThumbnail?: string) => Promise<any> }
-): Promise<void> {
-  await Promise.all(stirlingFileStubs.map(async ({ file, fileId, thumbnail }) => {
-    try {
-      await indexedDB.saveFile(file, fileId, thumbnail);
-    } catch (error) {
-      console.error('Failed to persist file to IndexedDB:', file.name, error);
-    }
-  }));
-}
 
 /**
  * Consume files helper - replace unpinned input files with output files
+ * Now accepts pre-created StirlingFiles and StirlingFileStubs to preserve all metadata
  */
 export async function consumeFiles(
   inputFileIds: FileId[],
-  outputFiles: File[],
+  outputStirlingFiles: StirlingFile[],
+  outputStirlingFileStubs: StirlingFileStub[],
   filesRef: React.MutableRefObject<Map<FileId, File>>,
-  dispatch: React.Dispatch<FileContextAction>,
-  indexedDB?: { saveFile: (file: File, fileId: FileId, existingThumbnail?: string) => Promise<any> } | null
+  dispatch: React.Dispatch<FileContextAction>
 ): Promise<FileId[]> {
-  if (DEBUG) console.log(`📄 consumeFiles: Processing ${inputFileIds.length} input files, ${outputFiles.length} output files`);
+  if (DEBUG) console.log(`📄 consumeFiles: Processing ${inputFileIds.length} input files, ${outputStirlingFiles.length} output files with pre-created stubs`);
 
-  // Process output files with thumbnails and metadata
-  const outputStirlingFileStubs = await processFilesIntoRecords(outputFiles, filesRef);
-
-  // Persist output files to IndexedDB if available
-  if (indexedDB) {
-    await persistFilesToIndexedDB(outputStirlingFileStubs, indexedDB);
+  // Validate that we have matching files and stubs
+  if (outputStirlingFiles.length !== outputStirlingFileStubs.length) {
+    throw new Error(`Mismatch between output files (${outputStirlingFiles.length}) and stubs (${outputStirlingFileStubs.length})`);
   }
 
-  // Dispatch the consume action
+  // Store StirlingFiles in filesRef using their existing IDs (no ID generation needed)
+  for (let i = 0; i < outputStirlingFiles.length; i++) {
+    const stirlingFile = outputStirlingFiles[i];
+    const stub = outputStirlingFileStubs[i];
+
+    if (stirlingFile.fileId !== stub.id) {
+      console.warn(`📄 consumeFiles: ID mismatch between StirlingFile (${stirlingFile.fileId}) and stub (${stub.id})`);
+    }
+
+    filesRef.current.set(stirlingFile.fileId, stirlingFile);
+
+    if (DEBUG) console.log(`📄 consumeFiles: Stored StirlingFile ${stirlingFile.name} with ID ${stirlingFile.fileId}`);
+  }
+
+  // Mark input files as processed in storage (no longer leaf nodes)
+  if(!outputStirlingFileStubs.reduce((areAllV1, stub) => areAllV1 && (stub.versionNumber == 1), true)) {
+    await Promise.all(
+      inputFileIds.map(async (fileId) => {
+        try {
+          await fileStorage.markFileAsProcessed(fileId);
+          if (DEBUG) console.log(`📄 Marked file ${fileId} as processed (no longer leaf)`);
+        } catch (error) {
+          if (DEBUG) console.warn(`📄 Failed to mark file ${fileId} as processed:`, error);
+        }
+      })
+    );
+  }
+
+  // Save output files directly to fileStorage with complete metadata
+  for (let i = 0; i < outputStirlingFiles.length; i++) {
+    const stirlingFile = outputStirlingFiles[i];
+    const stub = outputStirlingFileStubs[i];
+
+    try {
+      // Use fileStorage directly with complete metadata from stub
+      await fileStorage.storeStirlingFile(stirlingFile, stub);
+
+      if (DEBUG) console.log(`📄 Saved StirlingFile ${stirlingFile.name} directly to storage with complete metadata:`, {
+        fileId: stirlingFile.fileId,
+        versionNumber: stub.versionNumber,
+        originalFileId: stub.originalFileId,
+        parentFileId: stub.parentFileId,
+        toolChainLength: stub.toolHistory?.length || 0
+      });
+    } catch (error) {
+      console.error('Failed to persist output file to fileStorage:', stirlingFile.name, error);
+    }
+  }
+
+  // Dispatch the consume action with pre-created stubs (no processing needed)
   dispatch({
     type: 'CONSUME_FILES',
     payload: {
       inputFileIds,
-      outputStirlingFileStubs: outputStirlingFileStubs.map(({ record }) => record)
+      outputStirlingFileStubs: outputStirlingFileStubs
     }
   });
 
   if (DEBUG) console.log(`📄 consumeFiles: Successfully consumed files - removed ${inputFileIds.length} inputs, added ${outputStirlingFileStubs.length} outputs`);
   // Return the output file IDs for undo tracking
-  return outputStirlingFileStubs.map(({ fileId }) => fileId);
+  return outputStirlingFileStubs.map(stub => stub.id);
 }
 
 /**
@@ -518,6 +459,97 @@ export async function undoConsumeFiles(
 /**
  * Action factory functions
  */
+
+/**
+ * Add files using existing StirlingFileStubs from storage - preserves all metadata
+ * Use this when loading files that already exist in storage (FileManager, etc.)
+ * StirlingFileStubs come with proper thumbnails, history, processing state
+ */
+export async function addStirlingFileStubs(
+  stirlingFileStubs: StirlingFileStub[],
+  options: { insertAfterPageId?: string; selectFiles?: boolean } = {},
+  stateRef: React.MutableRefObject<FileContextState>,
+  filesRef: React.MutableRefObject<Map<FileId, File>>,
+  dispatch: React.Dispatch<FileContextAction>,
+  _lifecycleManager: FileLifecycleManager
+): Promise<StirlingFile[]> {
+  await addFilesMutex.lock();
+
+  try {
+    if (DEBUG) console.log(`📄 addStirlingFileStubs: Adding ${stirlingFileStubs.length} StirlingFileStubs preserving metadata`);
+
+    const existingQuickKeys = buildQuickKeySet(stateRef.current.files.byId);
+    const validStubs: StirlingFileStub[] = [];
+    const loadedFiles: StirlingFile[] = [];
+
+    for (const stub of stirlingFileStubs) {
+      // Check for duplicates using quickKey
+      if (existingQuickKeys.has(stub.quickKey || '')) {
+        if (DEBUG) console.log(`📄 Skipping duplicate StirlingFileStub: ${stub.name}`);
+        continue;
+      }
+
+      // Load the actual StirlingFile from storage
+      const stirlingFile = await fileStorage.getStirlingFile(stub.id);
+      if (!stirlingFile) {
+        console.warn(`📄 Failed to load StirlingFile for stub: ${stub.name} (${stub.id})`);
+        continue;
+      }
+
+      // Store the loaded file in filesRef
+      filesRef.current.set(stub.id, stirlingFile);
+
+      // Use the original stub (preserves thumbnails, history, metadata!)
+      const record = { ...stub };
+
+      // Store insertion position if provided
+      if (options.insertAfterPageId !== undefined) {
+        record.insertAfterPageId = options.insertAfterPageId;
+      }
+
+      // Check if processedFile data needs regeneration for proper Page Editor support
+      if (stirlingFile.type.startsWith('application/pdf')) {
+        const needsProcessing = !record.processedFile ||
+                                !record.processedFile.pages ||
+                                record.processedFile.pages.length === 0 ||
+                                record.processedFile.totalPages !== record.processedFile.pages.length;
+
+        if (needsProcessing) {
+          if (DEBUG) console.log(`📄 addStirlingFileStubs: Regenerating processedFile for ${record.name}`);
+
+          // Use centralized metadata generation function
+          const processedFileMetadata = await generateProcessedFileMetadata(stirlingFile);
+          if (processedFileMetadata) {
+            record.processedFile = processedFileMetadata;
+            record.thumbnailUrl = processedFileMetadata.thumbnailUrl; // Update thumbnail if needed
+            if (DEBUG) console.log(`📄 addStirlingFileStubs: Regenerated processedFile for ${record.name} with ${processedFileMetadata.totalPages} pages`);
+          } else {
+            // Fallback for files that couldn't be processed
+            if (DEBUG) console.warn(`📄 addStirlingFileStubs: Failed to regenerate processedFile for ${record.name}`);
+            if (!record.processedFile) {
+              record.processedFile = createProcessedFile(1); // Fallback to 1 page
+            }
+          }
+        }
+      }
+
+      existingQuickKeys.add(stub.quickKey || '');
+      validStubs.push(record);
+      loadedFiles.push(stirlingFile);
+    }
+
+    // Dispatch ADD_FILES action if we have new files
+    if (validStubs.length > 0) {
+      dispatch({ type: 'ADD_FILES', payload: { stirlingFileStubs: validStubs } });
+      if (DEBUG) console.log(`📄 addStirlingFileStubs: Successfully added ${validStubs.length} files with preserved metadata`);
+    }
+
+    return loadedFiles;
+  } finally {
+    addFilesMutex.unlock();
+  }
+}
+
 export const createFileActions = (dispatch: React.Dispatch<FileContextAction>) => ({
   setSelectedFiles: (fileIds: FileId[]) => dispatch({ type: 'SET_SELECTED_FILES', payload: { fileIds } }),
   setSelectedPages: (pageNumbers: number[]) => dispatch({ type: 'SET_SELECTED_PAGES', payload: { pageNumbers } }),

frontend/src/hooks/tools/addPassword/useAddPasswordOperation.test.ts

@@ -119,7 +119,6 @@ describe('useAddPasswordOperation', () => {
   test.each([
     { property: 'toolType' as const, expectedValue: ToolType.singleFile },
     { property: 'endpoint' as const, expectedValue: '/api/v1/security/add-password' },
-    { property: 'filePrefix' as const, expectedValue: 'translated-addPassword.filenamePrefix_' },
     { property: 'operationType' as const, expectedValue: 'addPassword' }
   ])('should configure $property correctly', ({ property, expectedValue }) => {
     renderHook(() => useAddPasswordOperation());

frontend/src/hooks/tools/addPassword/useAddPasswordOperation.ts

@@ -30,7 +30,6 @@ export const addPasswordOperationConfig = {
   buildFormData: buildAddPasswordFormData,
   operationType: 'addPassword',
   endpoint: '/api/v1/security/add-password',
-  filePrefix: 'encrypted_', // Will be overridden in hook with translation
   defaultParameters: fullDefaultParameters,
 } as const;
 
@@ -39,7 +38,6 @@ export const useAddPasswordOperation = () => {
 
   return useToolOperation<AddPasswordFullParameters>({
     ...addPasswordOperationConfig,
-    filePrefix: t('addPassword.filenamePrefix', 'encrypted') + '_',
     getErrorMessage: createStandardErrorHandler(t('addPassword.error.failed', 'An error occurred while encrypting the PDF.'))
   });
 };

frontend/src/hooks/tools/addWatermark/useAddWatermarkOperation.ts

@@ -39,7 +39,6 @@ export const addWatermarkOperationConfig = {
   buildFormData: buildAddWatermarkFormData,
   operationType: 'watermark',
   endpoint: '/api/v1/security/add-watermark',
-  filePrefix: 'watermarked_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -48,7 +47,6 @@ export const useAddWatermarkOperation = () => {
 
   return useToolOperation<AddWatermarkParameters>({
     ...addWatermarkOperationConfig,
-    filePrefix: t('watermark.filenamePrefix', 'watermarked') + '_',
     getErrorMessage: createStandardErrorHandler(t('watermark.error.failed', 'An error occurred while adding watermark to the PDF.'))
   });
 };

frontend/src/hooks/tools/adjustPageScale/useAdjustPageScaleOperation.ts

@@ -16,7 +16,6 @@ export const adjustPageScaleOperationConfig = {
   buildFormData: buildAdjustPageScaleFormData,
   operationType: 'adjustPageScale',
   endpoint: '/api/v1/general/scale-pages',
-  filePrefix: 'scaled_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/autoRename/useAutoRenameOperation.ts

@@ -28,7 +28,6 @@ export const autoRenameOperationConfig = {
   buildFormData: buildAutoRenameFormData,
   operationType: 'autoRename',
   endpoint: '/api/v1/misc/auto-rename',
-  filePrefix: 'autoRename_',
   preserveBackendFilename: true, // Use filename from backend response headers
   defaultParameters,
 } as const;

frontend/src/hooks/tools/automate/useAutomateOperation.ts

@@ -42,6 +42,5 @@ export function useAutomateOperation() {
     toolType: ToolType.custom,
     operationType: 'automate',
     customProcessor,
-    filePrefix: '' // No prefix needed since automation handles naming internally
   });
 }

frontend/src/hooks/tools/changePermissions/useChangePermissionsOperation.test.ts

@@ -113,7 +113,6 @@ describe('useChangePermissionsOperation', () => {
   test.each([
     { property: 'toolType' as const, expectedValue: ToolType.singleFile },
     { property: 'endpoint' as const, expectedValue: '/api/v1/security/add-password' },
-    { property: 'filePrefix' as const, expectedValue: 'permissions_' },
     { property: 'operationType' as const, expectedValue: 'change-permissions' }
   ])('should configure $property correctly', ({ property, expectedValue }) => {
     renderHook(() => useChangePermissionsOperation());

frontend/src/hooks/tools/changePermissions/useChangePermissionsOperation.ts

@@ -28,7 +28,6 @@ export const changePermissionsOperationConfig = {
   buildFormData: buildChangePermissionsFormData,
   operationType: 'change-permissions',
   endpoint: '/api/v1/security/add-password', // Change Permissions is a fake endpoint for the Add Password tool
-  filePrefix: 'permissions_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/compress/useCompressOperation.ts

@@ -28,7 +28,6 @@ export const compressOperationConfig = {
   buildFormData: buildCompressFormData,
   operationType: 'compress',
   endpoint: '/api/v1/misc/compress-pdf',
-  filePrefix: 'compressed_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/convert/useConvertOperation.ts

@@ -83,7 +83,7 @@ export const createFileFromResponse = (
     targetExtension = 'pdf';
   }
 
-  const fallbackFilename = `${originalName}_converted.${targetExtension}`;
+  const fallbackFilename = `${originalName}.${targetExtension}`;
 
   return createFileFromApiResponse(responseData, headers, fallbackFilename);
 };
@@ -136,7 +136,6 @@ export const convertOperationConfig = {
   toolType: ToolType.custom,
   customProcessor: convertProcessor, // Can't use callback version here
   operationType: 'convert',
-  filePrefix: 'converted_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/flatten/useFlattenOperation.ts

@@ -17,7 +17,6 @@ export const flattenOperationConfig = {
   buildFormData: buildFlattenFormData,
   operationType: 'flatten',
   endpoint: '/api/v1/misc/flatten',
-  filePrefix: 'flattened_', // Will be overridden in hook with translation
   multiFileEndpoint: false,
   defaultParameters,
 } as const;
@@ -27,7 +26,6 @@ export const useFlattenOperation = () => {
 
   return useToolOperation<FlattenParameters>({
     ...flattenOperationConfig,
-    filePrefix: t('flatten.filenamePrefix', 'flattened') + '_',
     getErrorMessage: createStandardErrorHandler(t('flatten.error.failed', 'An error occurred while flattening the PDF.'))
   });
-};
+};

frontend/src/hooks/tools/ocr/useOCROperation.ts

@@ -88,8 +88,8 @@ export const ocrResponseHandler = async (blob: Blob, originalFiles: File[], extr
     throw new Error(`Response is not a valid PDF. Header: "${head}"`);
   }
 
-  const base = stripExt(originalFiles[0].name);
-  return [new File([blob], `ocr_${base}.pdf`, { type: 'application/pdf' })];
+  const originalName = originalFiles[0].name;
+  return [new File([blob], originalName, { type: 'application/pdf' })];
 };
 
 // Static configuration object (without t function dependencies)
@@ -98,7 +98,6 @@ export const ocrOperationConfig = {
   buildFormData: buildOCRFormData,
   operationType: 'ocr',
   endpoint: '/api/v1/misc/ocr-pdf',
-  filePrefix: 'ocr_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/redact/useRedactOperation.ts

@@ -37,7 +37,6 @@ export const redactOperationConfig = {
       throw new Error('Manual redaction not yet implemented');
     }
   },
-  filePrefix: 'redacted_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/removeCertificateSign/useRemoveCertificateSignOperation.ts

@@ -16,7 +16,6 @@ export const removeCertificateSignOperationConfig = {
   buildFormData: buildRemoveCertificateSignFormData,
   operationType: 'remove-certificate-sign',
   endpoint: '/api/v1/security/remove-cert-sign',
-  filePrefix: 'unsigned_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -25,7 +24,6 @@ export const useRemoveCertificateSignOperation = () => {
 
   return useToolOperation<RemoveCertificateSignParameters>({
     ...removeCertificateSignOperationConfig,
-    filePrefix: t('removeCertSign.filenamePrefix', 'unsigned') + '_',
     getErrorMessage: createStandardErrorHandler(t('removeCertSign.error.failed', 'An error occurred while removing certificate signatures.'))
   });
 };

frontend/src/hooks/tools/removePassword/useRemovePasswordOperation.test.ts

@@ -97,7 +97,6 @@ describe('useRemovePasswordOperation', () => {
   test.each([
     { property: 'toolType' as const, expectedValue: ToolType.singleFile },
     { property: 'endpoint' as const, expectedValue: '/api/v1/security/remove-password' },
-    { property: 'filePrefix' as const, expectedValue: 'translated-removePassword.filenamePrefix_' },
     { property: 'operationType' as const, expectedValue: 'removePassword' }
   ])('should configure $property correctly', ({ property, expectedValue }) => {
     renderHook(() => useRemovePasswordOperation());

frontend/src/hooks/tools/removePassword/useRemovePasswordOperation.ts

@@ -17,7 +17,6 @@ export const removePasswordOperationConfig = {
   buildFormData: buildRemovePasswordFormData,
   operationType: 'removePassword',
   endpoint: '/api/v1/security/remove-password',
-  filePrefix: 'decrypted_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -26,7 +25,6 @@ export const useRemovePasswordOperation = () => {
 
   return useToolOperation<RemovePasswordParameters>({
     ...removePasswordOperationConfig,
-    filePrefix: t('removePassword.filenamePrefix', 'decrypted') + '_',
     getErrorMessage: createStandardErrorHandler(t('removePassword.error.failed', 'An error occurred while removing the password from the PDF.'))
   });
 };

frontend/src/hooks/tools/repair/useRepairOperation.ts

@@ -16,7 +16,6 @@ export const repairOperationConfig = {
   buildFormData: buildRepairFormData,
   operationType: 'repair',
   endpoint: '/api/v1/misc/repair',
-  filePrefix: 'repaired_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -25,7 +24,6 @@ export const useRepairOperation = () => {
 
   return useToolOperation<RepairParameters>({
     ...repairOperationConfig,
-    filePrefix: t('repair.filenamePrefix', 'repaired') + '_',
     getErrorMessage: createStandardErrorHandler(t('repair.error.failed', 'An error occurred while repairing the PDF.'))
   });
 };

frontend/src/hooks/tools/sanitize/useSanitizeOperation.ts

@@ -25,7 +25,6 @@ export const sanitizeOperationConfig = {
   buildFormData: buildSanitizeFormData,
   operationType: 'sanitize',
   endpoint: '/api/v1/security/sanitize-pdf',
-  filePrefix: 'sanitized_', // Will be overridden in hook with translation
   multiFileEndpoint: false,
   defaultParameters,
 } as const;
@@ -35,7 +34,6 @@ export const useSanitizeOperation = () => {
 
   return useToolOperation<SanitizeParameters>({
     ...sanitizeOperationConfig,
-    filePrefix: t('sanitize.filenamePrefix', 'sanitized') + '_',
     getErrorMessage: createStandardErrorHandler(t('sanitize.error.failed', 'An error occurred while sanitising the PDF.'))
   });
 };

frontend/src/hooks/tools/shared/useBaseTool.ts

@@ -6,12 +6,12 @@ import { ToolOperationHook } from './useToolOperation';
 import { BaseParametersHook } from './useBaseParameters';
 import { StirlingFile } from '../../../types/fileContext';
 
-interface BaseToolReturn<TParams> {
+interface BaseToolReturn<TParams, TParamsHook extends BaseParametersHook<TParams>> {
   // File management
   selectedFiles: StirlingFile[];
 
   // Tool-specific hooks
-  params: BaseParametersHook<TParams>;
+  params: TParamsHook;
   operation: ToolOperationHook<TParams>;
 
   // Endpoint validation
@@ -33,13 +33,13 @@ interface BaseToolReturn<TParams> {
 /**
  * Base tool hook for tool components. Manages standard behaviour for tools.
  */
-export function useBaseTool<TParams>(
+export function useBaseTool<TParams, TParamsHook extends BaseParametersHook<TParams>>(
   toolName: string,
-  useParams: () => BaseParametersHook<TParams>,
+  useParams: () => TParamsHook,
   useOperation: () => ToolOperationHook<TParams>,
   props: BaseToolProps,
   options?: { minFiles?: number }
-): BaseToolReturn<TParams> {
+): BaseToolReturn<TParams, TParamsHook> {
   const minFiles = options?.minFiles ?? 1;
   const { onPreviewFile, onComplete, onError } = props;
 

frontend/src/hooks/tools/shared/useToolApiCalls.ts

@@ -6,7 +6,7 @@ import type { ProcessingProgress } from './useToolState';
 export interface ApiCallsConfig<TParams = void> {
   endpoint: string | ((params: TParams) => string);
   buildFormData: (params: TParams, file: File) => FormData;
-  filePrefix: string;
+  filePrefix?: string;
   responseHandler?: ResponseHandler;
   preserveBackendFilename?: boolean;
 }

frontend/src/hooks/tools/shared/useToolOperation.ts

@@ -6,8 +6,9 @@ import { useToolState, type ProcessingProgress } from './useToolState';
 import { useToolApiCalls, type ApiCallsConfig } from './useToolApiCalls';
 import { useToolResources } from './useToolResources';
 import { extractErrorMessage } from '../../../utils/toolErrorHandler';
-import { StirlingFile, extractFiles, FileId, StirlingFileStub } from '../../../types/fileContext';
+import { StirlingFile, extractFiles, FileId, StirlingFileStub, createStirlingFile, createNewStirlingFileStub } from '../../../types/fileContext';
 import { ResponseHandler } from '../../../utils/toolResponseProcessor';
+import { createChildStub, generateProcessedFileMetadata } from '../../../contexts/file/fileActions';
 
 // Re-export for backwards compatibility
 export type { ProcessingProgress, ResponseHandler };
@@ -31,7 +32,7 @@ interface BaseToolOperationConfig<TParams> {
   operationType: string;
 
   /** Prefix added to processed filenames (e.g., 'compressed_', 'split_') */
-  filePrefix: string;
+  filePrefix?: string;
 
   /**
    * Whether to preserve the filename provided by the backend in response headers.
@@ -165,18 +166,20 @@ export const useToolOperation = <TParams>(
       return;
     }
 
-
     // Reset state
     actions.setLoading(true);
     actions.setError(null);
     actions.resetResults();
     cleanupBlobUrls();
 
+    // Prepare files with history metadata injection (for PDFs)
+    actions.setStatus('Processing files...');
+
     try {
       let processedFiles: File[];
 
-      // Convert StirlingFile to regular File objects for API processing
-      const validRegularFiles = extractFiles(validFiles);
+      // Use original files directly (no PDF metadata injection - history stored in IndexedDB)
+      const filesForAPI = extractFiles(validFiles);
 
       switch (config.toolType) {
         case ToolType.singleFile: {
@@ -190,18 +193,17 @@ export const useToolOperation = <TParams>(
           };
           processedFiles = await processFiles(
             params,
-            validRegularFiles,
+            filesForAPI,
             apiCallsConfig,
             actions.setProgress,
             actions.setStatus
           );
           break;
         }
-
         case ToolType.multiFile: {
           // Multi-file processing - single API call with all files
           actions.setStatus('Processing files...');
-          const formData = config.buildFormData(params, validRegularFiles);
+          const formData = config.buildFormData(params, filesForAPI);
           const endpoint = typeof config.endpoint === 'function' ? config.endpoint(params) : config.endpoint;
 
           const response = await axios.post(endpoint, formData, { responseType: 'blob' });
@@ -209,11 +211,11 @@ export const useToolOperation = <TParams>(
           // Multi-file responses are typically ZIP files that need extraction, but some may return single PDFs
           if (config.responseHandler) {
             // Use custom responseHandler for multi-file (handles ZIP extraction)
-            processedFiles = await config.responseHandler(response.data, validRegularFiles);
+            processedFiles = await config.responseHandler(response.data, filesForAPI);
           } else if (response.data.type === 'application/pdf' ||
                     (response.headers && response.headers['content-type'] === 'application/pdf')) {
             // Single PDF response (e.g. split with merge option) - use original filename
-            const originalFileName = validRegularFiles[0]?.name || 'document.pdf';
+            const originalFileName = filesForAPI[0]?.name || 'document.pdf';
             const singleFile = new File([response.data], originalFileName, { type: 'application/pdf' });
             processedFiles = [singleFile];
           } else {
@@ -230,13 +232,14 @@ export const useToolOperation = <TParams>(
 
         case ToolType.custom:
           actions.setStatus('Processing files...');
-          processedFiles = await config.customProcessor(params, validRegularFiles);
+          processedFiles = await config.customProcessor(params, filesForAPI);
           break;
       }
 
       if (processedFiles.length > 0) {
         actions.setFiles(processedFiles);
 
+
         // Generate thumbnails and download URL concurrently
         actions.setGeneratingThumbnails(true);
         const [thumbnails, downloadInfo] = await Promise.all([
@@ -264,7 +267,40 @@ export const useToolOperation = <TParams>(
           }
         }
 
-        const outputFileIds = await consumeFiles(inputFileIds, processedFiles);
+        // Create new tool operation
+        const newToolOperation = {
+          toolName: config.operationType,
+          timestamp: Date.now()
+        };
+
+        // Generate fresh processedFileMetadata for all processed files to ensure accuracy
+        actions.setStatus('Generating metadata for processed files...');
+        const processedFileMetadataArray = await Promise.all(
+          processedFiles.map(file => generateProcessedFileMetadata(file))
+        );
+        const shouldBranchHistory = processedFiles.length != inputStirlingFileStubs.length;
+        // Create output stubs with fresh metadata (no inheritance of stale processedFile data)
+        const outputStirlingFileStubs = shouldBranchHistory
+          ? processedFiles.map((file, index) =>
+              createNewStirlingFileStub(file, undefined, thumbnails[index], processedFileMetadataArray[index])
+            )
+          : processedFiles.map((resultingFile, index) =>
+              createChildStub(
+                inputStirlingFileStubs[index],
+                newToolOperation,
+                resultingFile,
+                thumbnails[index],
+                processedFileMetadataArray[index]
+              )
+            );
+
+        // Create StirlingFile objects from processed files and child stubs
+        const outputStirlingFiles = processedFiles.map((file, index) => {
+          const childStub = outputStirlingFileStubs[index];
+          return createStirlingFile(file, childStub.id);
+        });
+
+        const outputFileIds = await consumeFiles(inputFileIds, outputStirlingFiles, outputStirlingFileStubs);
 
         // Store operation data for undo (only store what we need to avoid memory bloat)
         lastOperationRef.current = {

frontend/src/hooks/tools/singleLargePage/useSingleLargePageOperation.ts

@@ -16,7 +16,6 @@ export const singleLargePageOperationConfig = {
   buildFormData: buildSingleLargePageFormData,
   operationType: 'single-large-page',
   endpoint: '/api/v1/general/pdf-to-single-page',
-  filePrefix: 'single_page_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -25,7 +24,6 @@ export const useSingleLargePageOperation = () => {
 
   return useToolOperation<SingleLargePageParameters>({
     ...singleLargePageOperationConfig,
-    filePrefix: t('pdfToSinglePage.filenamePrefix', 'single_page') + '_',
     getErrorMessage: createStandardErrorHandler(t('pdfToSinglePage.error.failed', 'An error occurred while converting to single page.'))
   });
 };

frontend/src/hooks/tools/split/useSplitOperation.ts

@@ -3,7 +3,7 @@ import { useTranslation } from 'react-i18next';
 import { ToolType, useToolOperation, ToolOperationConfig } from '../shared/useToolOperation';
 import { createStandardErrorHandler } from '../../../utils/toolErrorHandler';
 import { SplitParameters, defaultParameters } from './useSplitParameters';
-import { SPLIT_MODES } from '../../../constants/splitConstants';
+import { SPLIT_METHODS } from '../../../constants/splitConstants';
 import { useToolResources } from '../shared/useToolResources';
 
 // Static functions that can be used by both the hook and automation executor
@@ -12,46 +12,58 @@ export const buildSplitFormData = (parameters: SplitParameters, file: File): For
 
   formData.append("fileInput", file);
 
-  switch (parameters.mode) {
-    case SPLIT_MODES.BY_PAGES:
+  switch (parameters.method) {
+    case SPLIT_METHODS.BY_PAGES:
       formData.append("pageNumbers", parameters.pages);
       break;
-    case SPLIT_MODES.BY_SECTIONS:
+    case SPLIT_METHODS.BY_SECTIONS:
       formData.append("horizontalDivisions", parameters.hDiv);
       formData.append("verticalDivisions", parameters.vDiv);
       formData.append("merge", parameters.merge.toString());
       break;
-    case SPLIT_MODES.BY_SIZE_OR_COUNT:
-      formData.append(
-        "splitType",
-        parameters.splitType === "size" ? "0" : parameters.splitType === "pages" ? "1" : "2"
-      );
+    case SPLIT_METHODS.BY_SIZE:
+      formData.append("splitType", "0");
       formData.append("splitValue", parameters.splitValue);
       break;
-    case SPLIT_MODES.BY_CHAPTERS:
+    case SPLIT_METHODS.BY_PAGE_COUNT:
+      formData.append("splitType", "1");
+      formData.append("splitValue", parameters.splitValue);
+      break;
+    case SPLIT_METHODS.BY_DOC_COUNT:
+      formData.append("splitType", "2");
+      formData.append("splitValue", parameters.splitValue);
+      break;
+    case SPLIT_METHODS.BY_CHAPTERS:
       formData.append("bookmarkLevel", parameters.bookmarkLevel);
       formData.append("includeMetadata", parameters.includeMetadata.toString());
       formData.append("allowDuplicates", parameters.allowDuplicates.toString());
       break;
+    case SPLIT_METHODS.BY_PAGE_DIVIDER:
+      formData.append("duplexMode", parameters.duplexMode.toString());
+      break;
     default:
-      throw new Error(`Unknown split mode: ${parameters.mode}`);
+      throw new Error(`Unknown split method: ${parameters.method}`);
   }
 
   return formData;
 };
 
 export const getSplitEndpoint = (parameters: SplitParameters): string => {
-  switch (parameters.mode) {
-    case SPLIT_MODES.BY_PAGES:
+  switch (parameters.method) {
+    case SPLIT_METHODS.BY_PAGES:
       return "/api/v1/general/split-pages";
-    case SPLIT_MODES.BY_SECTIONS:
+    case SPLIT_METHODS.BY_SECTIONS:
       return "/api/v1/general/split-pdf-by-sections";
-    case SPLIT_MODES.BY_SIZE_OR_COUNT:
+    case SPLIT_METHODS.BY_SIZE:
+    case SPLIT_METHODS.BY_PAGE_COUNT:
+    case SPLIT_METHODS.BY_DOC_COUNT:
       return "/api/v1/general/split-by-size-or-count";
-    case SPLIT_MODES.BY_CHAPTERS:
+    case SPLIT_METHODS.BY_CHAPTERS:
       return "/api/v1/general/split-pdf-by-chapters";
+    case SPLIT_METHODS.BY_PAGE_DIVIDER:
+      return "/api/v1/misc/auto-split-pdf";
     default:
-      throw new Error(`Unknown split mode: ${parameters.mode}`);
+      throw new Error(`Unknown split method: ${parameters.method}`);
   }
 };
 
@@ -61,7 +73,6 @@ export const splitOperationConfig = {
   buildFormData: buildSplitFormData,
   operationType: 'splitPdf',
   endpoint: getSplitEndpoint,
-  filePrefix: 'split_',
   defaultParameters,
 } as const;
 

frontend/src/hooks/tools/split/useSplitParameters.ts

@@ -1,54 +1,58 @@
-import { SPLIT_MODES, SPLIT_TYPES, ENDPOINTS, type SplitMode, SplitType } from '../../../constants/splitConstants';
+import { SPLIT_METHODS, ENDPOINTS, type SplitMethod } from '../../../constants/splitConstants';
 import { BaseParameters } from '../../../types/parameters';
 import { useBaseParameters, BaseParametersHook } from '../shared/useBaseParameters';
 
 export interface SplitParameters extends BaseParameters {
-  mode: SplitMode | '';
+  method: SplitMethod | '';
   pages: string;
   hDiv: string;
   vDiv: string;
   merge: boolean;
-  splitType: SplitType | '';
   splitValue: string;
   bookmarkLevel: string;
   includeMetadata: boolean;
   allowDuplicates: boolean;
+  duplexMode: boolean;
 }
 
 export type SplitParametersHook = BaseParametersHook<SplitParameters>;
 
 export const defaultParameters: SplitParameters = {
-  mode: '',
+  method: '',
   pages: '',
   hDiv: '2',
   vDiv: '2',
   merge: false,
-  splitType: SPLIT_TYPES.SIZE,
   splitValue: '',
   bookmarkLevel: '1',
   includeMetadata: false,
   allowDuplicates: false,
+  duplexMode: false,
 };
 
 export const useSplitParameters = (): SplitParametersHook => {
   return useBaseParameters({
     defaultParameters,
     endpointName: (params) => {
-      if (!params.mode) return ENDPOINTS[SPLIT_MODES.BY_PAGES];
-      return ENDPOINTS[params.mode as SplitMode];
+      if (!params.method) return ENDPOINTS[SPLIT_METHODS.BY_PAGES];
+      return ENDPOINTS[params.method as SplitMethod];
     },
     validateFn: (params) => {
-      if (!params.mode) return false;
+      if (!params.method) return false;
 
-      switch (params.mode) {
-        case SPLIT_MODES.BY_PAGES:
+      switch (params.method) {
+        case SPLIT_METHODS.BY_PAGES:
           return params.pages.trim() !== "";
-        case SPLIT_MODES.BY_SECTIONS:
+        case SPLIT_METHODS.BY_SECTIONS:
           return params.hDiv !== "" && params.vDiv !== "";
-        case SPLIT_MODES.BY_SIZE_OR_COUNT:
+        case SPLIT_METHODS.BY_SIZE:
+        case SPLIT_METHODS.BY_PAGE_COUNT:
+        case SPLIT_METHODS.BY_DOC_COUNT:
           return params.splitValue.trim() !== "";
-        case SPLIT_MODES.BY_CHAPTERS:
+        case SPLIT_METHODS.BY_CHAPTERS:
           return params.bookmarkLevel !== "";
+        case SPLIT_METHODS.BY_PAGE_DIVIDER:
+          return true; // No required parameters
         default:
           return false;
       }

frontend/src/hooks/tools/unlockPdfForms/useUnlockPdfFormsOperation.ts

@@ -16,7 +16,6 @@ export const unlockPdfFormsOperationConfig = {
   buildFormData: buildUnlockPdfFormsFormData,
   operationType: 'unlock-pdf-forms',
   endpoint: '/api/v1/misc/unlock-pdf-forms',
-  filePrefix: 'unlocked_forms_', // Will be overridden in hook with translation
   defaultParameters,
 } as const;
 
@@ -25,7 +24,6 @@ export const useUnlockPdfFormsOperation = () => {
 
   return useToolOperation<UnlockPdfFormsParameters>({
     ...unlockPdfFormsOperationConfig,
-    filePrefix: t('unlockPDFForms.filenamePrefix', 'unlocked_forms') + '_',
     getErrorMessage: createStandardErrorHandler(t('unlockPDFForms.error.failed', 'An error occurred while unlocking PDF forms.'))
   });
 };

frontend/src/hooks/useFileHandler.ts

@@ -1,39 +1,17 @@
 import { useCallback } from 'react';
-import { useFileState, useFileActions } from '../contexts/FileContext';
-import { FileMetadata } from '../types/file';
-import { FileId } from '../types/file';
+import { useFileActions } from '../contexts/FileContext';
 
 export const useFileHandler = () => {
-  const { state } = useFileState(); // Still needed for addStoredFiles
   const { actions } = useFileActions();
 
-  const addToActiveFiles = useCallback(async (file: File) => {
+  const addFiles = useCallback(async (files: File[], options: { insertAfterPageId?: string; selectFiles?: boolean } = {}) => {
+    // Merge default options with passed options - passed options take precedence
+    const mergedOptions = { selectFiles: true, ...options };
     // Let FileContext handle deduplication with quickKey logic
-    await actions.addFiles([file], { selectFiles: true });
+    await actions.addFiles(files, mergedOptions);
   }, [actions.addFiles]);
 
-  const addMultipleFiles = useCallback(async (files: File[]) => {
-    // Let FileContext handle deduplication with quickKey logic
-    await actions.addFiles(files, { selectFiles: true });
-  }, [actions.addFiles]);
-
-  // Add stored files preserving their original IDs to prevent session duplicates
-  const addStoredFiles = useCallback(async (filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>) => {
-    // Filter out files that already exist with the same ID (exact match)
-    const newFiles = filesWithMetadata.filter(({ originalId }) => {
-      return state.files.byId[originalId] === undefined;
-    });
-
-    if (newFiles.length > 0) {
-      await actions.addStoredFiles(newFiles, { selectFiles: true });
-    }
-
-    console.log(`📁 Added ${newFiles.length} stored files (${filesWithMetadata.length - newFiles.length} skipped as duplicates)`);
-  }, [state.files.byId, actions.addStoredFiles]);
-
   return {
-    addToActiveFiles,
-    addMultipleFiles,
-    addStoredFiles,
+    addFiles,
   };
 };

frontend/src/hooks/useFileManager.ts

@@ -1,72 +1,40 @@
 import { useState, useCallback } from 'react';
 import { useIndexedDB } from '../contexts/IndexedDBContext';
-import { FileMetadata } from '../types/file';
+import { fileStorage } from '../services/fileStorage';
+import { StirlingFileStub, StirlingFile } from '../types/fileContext';
 import { FileId } from '../types/fileContext';
 
 export const useFileManager = () => {
   const [loading, setLoading] = useState(false);
   const indexedDB = useIndexedDB();
 
-  const convertToFile = useCallback(async (fileMetadata: FileMetadata): Promise<File> => {
+  const convertToFile = useCallback(async (fileStub: StirlingFileStub): Promise<File> => {
     if (!indexedDB) {
       throw new Error('IndexedDB context not available');
     }
 
-    // Handle drafts differently from regular files
-    if (fileMetadata.isDraft) {
-      // Load draft from the drafts database
-      try {
-        const { indexedDBManager, DATABASE_CONFIGS } = await import('../services/indexedDBManager');
-        const db = await indexedDBManager.openDatabase(DATABASE_CONFIGS.DRAFTS);
-
-        return new Promise((resolve, reject) => {
-          const transaction = db.transaction(['drafts'], 'readonly');
-          const store = transaction.objectStore('drafts');
-          const request = store.get(fileMetadata.id);
-
-          request.onsuccess = () => {
-            const draft = request.result;
-            if (draft && draft.pdfData) {
-              const file = new File([draft.pdfData], fileMetadata.name, {
-                type: 'application/pdf',
-                lastModified: fileMetadata.lastModified
-              });
-              resolve(file);
-            } else {
-              reject(new Error('Draft data not found'));
-            }
-          };
-
-          request.onerror = () => reject(request.error);
-        });
-      } catch (error) {
-        throw new Error(`Failed to load draft: ${fileMetadata.name} (${error})`);
-      }
-    }
-
     // Regular file loading
-    if (fileMetadata.id) {
-      const file = await indexedDB.loadFile(fileMetadata.id);
+    if (fileStub.id) {
+      const file = await indexedDB.loadFile(fileStub.id);
       if (file) {
         return file;
       }
     }
-    throw new Error(`File not found in storage: ${fileMetadata.name} (ID: ${fileMetadata.id})`);
+    throw new Error(`File not found in storage: ${fileStub.name} (ID: ${fileStub.id})`);
   }, [indexedDB]);
 
-  const loadRecentFiles = useCallback(async (): Promise<FileMetadata[]> => {
+  const loadRecentFiles = useCallback(async (): Promise<StirlingFileStub[]> => {
     setLoading(true);
     try {
       if (!indexedDB) {
         return [];
       }
 
-      // Load regular files metadata only
-      const storedFileMetadata = await indexedDB.loadAllMetadata();
+      // Load only leaf files metadata (processed files that haven't been used as input for other tools)
+      const stirlingFileStubs = await fileStorage.getLeafStirlingFileStubs();
 
       // For now, only regular files - drafts will be handled separately in the future
-      const allFiles = storedFileMetadata;
-      const sortedFiles = allFiles.sort((a, b) => (b.lastModified || 0) - (a.lastModified || 0));
+      const sortedFiles = stirlingFileStubs.sort((a, b) => (b.lastModified || 0) - (a.lastModified || 0));
 
       return sortedFiles;
     } catch (error) {
@@ -77,7 +45,7 @@ export const useFileManager = () => {
     }
   }, [indexedDB]);
 
-  const handleRemoveFile = useCallback(async (index: number, files: FileMetadata[], setFiles: (files: FileMetadata[]) => void) => {
+  const handleRemoveFile = useCallback(async (index: number, files: StirlingFileStub[], setFiles: (files: StirlingFileStub[]) => void) => {
     const file = files[index];
     if (!file.id) {
       throw new Error('File ID is required for removal');
@@ -102,10 +70,10 @@ export const useFileManager = () => {
       // Store file with provided UUID from FileContext (thumbnail generated internally)
       const metadata = await indexedDB.saveFile(file, fileId);
 
-      // Convert file to ArrayBuffer for StoredFile interface compatibility
+      // Convert file to ArrayBuffer for storage compatibility
       const arrayBuffer = await file.arrayBuffer();
 
-      // Return StoredFile format for compatibility with old API
+      // This method is deprecated - use FileStorage directly instead
       return {
         id: fileId,
         name: file.name,
@@ -113,7 +81,7 @@ export const useFileManager = () => {
         size: file.size,
         lastModified: file.lastModified,
         data: arrayBuffer,
-        thumbnail: metadata.thumbnail
+        thumbnail: metadata.thumbnailUrl
       };
     } catch (error) {
       console.error('Failed to store file:', error);
@@ -137,23 +105,24 @@ export const useFileManager = () => {
       setSelectedFiles([]);
     };
 
-    const selectMultipleFiles = async (files: FileMetadata[], onStoredFilesSelect: (filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>) => void) => {
+    const selectMultipleFiles = async (files: StirlingFileStub[], onStirlingFilesSelect: (stirlingFiles: StirlingFile[]) => void) => {
       if (selectedFiles.length === 0) return;
 
       try {
-        // Filter by UUID and convert to File objects
+        // Filter by UUID and load full StirlingFile objects directly
         const selectedFileObjects = files.filter(f => selectedFiles.includes(f.id));
 
-        // Use stored files flow that preserves IDs
-        const filesWithMetadata = await Promise.all(
-          selectedFileObjects.map(async (metadata) => ({
-            file: await convertToFile(metadata),
-            originalId: metadata.id,
-            metadata
-          }))
+        const stirlingFiles = await Promise.all(
+          selectedFileObjects.map(async (stub) => {
+            const stirlingFile = await fileStorage.getStirlingFile(stub.id);
+            if (!stirlingFile) {
+              throw new Error(`File not found in storage: ${stub.name}`);
+            }
+            return stirlingFile;
+          })
         );
-        onStoredFilesSelect(filesWithMetadata);
 
+        onStirlingFilesSelect(stirlingFiles);
         clearSelection();
       } catch (error) {
         console.error('Failed to load selected files:', error);

frontend/src/hooks/useIndexedDBThumbnail.ts

@@ -1,5 +1,5 @@
 import { useState, useEffect } from "react";
-import { FileMetadata } from "../types/file";
+import { StirlingFileStub } from "../types/fileContext";
 import { useIndexedDB } from "../contexts/IndexedDBContext";
 import { generateThumbnailForFile } from "../utils/thumbnailUtils";
 import { FileId } from "../types/fileContext";
@@ -9,7 +9,7 @@ import { FileId } from "../types/fileContext";
  * Hook for IndexedDB-aware thumbnail loading
  * Handles thumbnail generation for files not in IndexedDB
  */
-export function useIndexedDBThumbnail(file: FileMetadata | undefined | null): {
+export function useIndexedDBThumbnail(file: StirlingFileStub | undefined | null): {
   thumbnail: string | null;
   isGenerating: boolean
 } {
@@ -27,8 +27,8 @@ export function useIndexedDBThumbnail(file: FileMetadata | undefined | null): {
       }
 
       // First priority: use stored thumbnail
-      if (file.thumbnail) {
-        setThumb(file.thumbnail);
+      if (file.thumbnailUrl) {
+        setThumb(file.thumbnailUrl);
         return;
       }
 
@@ -77,7 +77,7 @@ export function useIndexedDBThumbnail(file: FileMetadata | undefined | null): {
 
     loadThumbnail();
     return () => { cancelled = true; };
-  }, [file, file?.thumbnail, file?.id, indexedDB, generating]);
+  }, [file, file?.thumbnailUrl, file?.id, indexedDB, generating]);
 
   return { thumbnail: thumb, isGenerating: generating };
 }

frontend/src/services/fileStorage.ts

@@ -1,19 +1,21 @@
 /**
- * IndexedDB File Storage Service
- * Provides high-capacity file storage for PDF processing
- * Now uses centralized IndexedDB manager
+ * Stirling File Storage Service
+ * Single-table architecture with typed query methods
+ * Forces correct usage patterns through service API design
  */
 
-import { FileId } from '../types/file';
+import { FileId, BaseFileMetadata } from '../types/file';
+import { StirlingFile, StirlingFileStub, createStirlingFile } from '../types/fileContext';
 import { indexedDBManager, DATABASE_CONFIGS } from './indexedDBManager';
 
-export interface StoredFile {
-  id: FileId;
-  name: string;
-  type: string;
-  size: number;
-  lastModified: number;
+/**
+ * Storage record - single source of truth
+ * Contains all data needed for both StirlingFile and StirlingFileStub
+ */
+export interface StoredStirlingFileRecord extends BaseFileMetadata {
   data: ArrayBuffer;
+  fileId: FileId; // Matches runtime StirlingFile.fileId exactly
+  quickKey: string; // Matches runtime StirlingFile.quickKey exactly
   thumbnail?: string;
   url?: string; // For compatibility with existing components
 }
@@ -37,47 +39,49 @@ class FileStorageService {
   }
 
   /**
-   * Store a file in IndexedDB with external UUID
+   * Store a StirlingFile with its metadata from StirlingFileStub
    */
-  async storeFile(file: File, fileId: FileId, thumbnail?: string): Promise<StoredFile> {
+  async storeStirlingFile(stirlingFile: StirlingFile, stub: StirlingFileStub): Promise<void> {
     const db = await this.getDatabase();
+    const arrayBuffer = await stirlingFile.arrayBuffer();
 
-    const arrayBuffer = await file.arrayBuffer();
-
-    const storedFile: StoredFile = {
-      id: fileId, // Use provided UUID
-      name: file.name,
-      type: file.type,
-      size: file.size,
-      lastModified: file.lastModified,
+    const record: StoredStirlingFileRecord = {
+      id: stirlingFile.fileId,
+      fileId: stirlingFile.fileId, // Explicit field for clarity
+      quickKey: stirlingFile.quickKey,
+      name: stirlingFile.name,
+      type: stirlingFile.type,
+      size: stirlingFile.size,
+      lastModified: stirlingFile.lastModified,
       data: arrayBuffer,
-      thumbnail
+      thumbnail: stub.thumbnailUrl,
+      isLeaf: stub.isLeaf ?? true,
+
+      // History data from stub
+      versionNumber: stub.versionNumber ?? 1,
+      originalFileId: stub.originalFileId ?? stirlingFile.fileId,
+      parentFileId: stub.parentFileId ?? undefined,
+      toolHistory: stub.toolHistory ?? []
     };
 
     return new Promise((resolve, reject) => {
       try {
+        // Verify store exists before creating transaction
+        if (!db.objectStoreNames.contains(this.storeName)) {
+          throw new Error(`Object store '${this.storeName}' not found. Available stores: ${Array.from(db.objectStoreNames).join(', ')}`);
+        }
+
         const transaction = db.transaction([this.storeName], 'readwrite');
         const store = transaction.objectStore(this.storeName);
 
-        // Debug logging
-        console.log('Object store keyPath:', store.keyPath);
-        console.log('Storing file with UUID:', {
-          id: storedFile.id, // Now a UUID from FileContext
-          name: storedFile.name,
-          hasData: !!storedFile.data,
-          dataSize: storedFile.data.byteLength
-        });
-
-        const request = store.add(storedFile);
+        const request = store.add(record);
 
         request.onerror = () => {
           console.error('IndexedDB add error:', request.error);
-          console.error('Failed object:', storedFile);
           reject(request.error);
         };
         request.onsuccess = () => {
-          console.log('File stored successfully with ID:', storedFile.id);
-          resolve(storedFile);
+          resolve();
         };
       } catch (error) {
         console.error('Transaction error:', error);
@@ -87,9 +91,9 @@ class FileStorageService {
   }
 
   /**
-   * Retrieve a file from IndexedDB
+   * Get StirlingFile with full data - for loading into workbench
    */
-  async getFile(id: FileId): Promise<StoredFile | null> {
+  async getStirlingFile(id: FileId): Promise<StirlingFile | null> {
     const db = await this.getDatabase();
 
     return new Promise((resolve, reject) => {
@@ -97,77 +101,167 @@ class FileStorageService {
       const store = transaction.objectStore(this.storeName);
       const request = store.get(id);
 
-      request.onerror = () => reject(request.error);
-      request.onsuccess = () => resolve(request.result || null);
-    });
-  }
-
-  /**
-   * Get all stored files (WARNING: loads all data into memory)
-   */
-  async getAllFiles(): Promise<StoredFile[]> {
-    const db = await this.getDatabase();
-
-    return new Promise((resolve, reject) => {
-      const transaction = db.transaction([this.storeName], 'readonly');
-      const store = transaction.objectStore(this.storeName);
-      const request = store.getAll();
-
       request.onerror = () => reject(request.error);
       request.onsuccess = () => {
-        // Filter out null/corrupted entries
-        const files = request.result.filter(file =>
-          file &&
-          file.data &&
-          file.name &&
-          typeof file.size === 'number'
-        );
-        resolve(files);
+        const record = request.result as StoredStirlingFileRecord | undefined;
+        if (!record) {
+          resolve(null);
+          return;
+        }
+
+        // Create File from stored data
+        const blob = new Blob([record.data], { type: record.type });
+        const file = new File([blob], record.name, {
+          type: record.type,
+          lastModified: record.lastModified
+        });
+
+        // Convert to StirlingFile with preserved IDs
+        const stirlingFile = createStirlingFile(file, record.fileId);
+        resolve(stirlingFile);
       };
     });
   }
 
   /**
-   * Get metadata of all stored files (without loading data into memory)
+   * Get multiple StirlingFiles - for batch loading
    */
-  async getAllFileMetadata(): Promise<Omit<StoredFile, 'data'>[]> {
+  async getStirlingFiles(ids: FileId[]): Promise<StirlingFile[]> {
+    const results = await Promise.all(ids.map(id => this.getStirlingFile(id)));
+    return results.filter((file): file is StirlingFile => file !== null);
+  }
+
+  /**
+   * Get StirlingFileStub (metadata only) - for UI browsing
+   */
+  async getStirlingFileStub(id: FileId): Promise<StirlingFileStub | null> {
+    const db = await this.getDatabase();
+
+    return new Promise((resolve, reject) => {
+      const transaction = db.transaction([this.storeName], 'readonly');
+      const store = transaction.objectStore(this.storeName);
+      const request = store.get(id);
+
+      request.onerror = () => reject(request.error);
+      request.onsuccess = () => {
+        const record = request.result as StoredStirlingFileRecord | undefined;
+        if (!record) {
+          resolve(null);
+          return;
+        }
+
+        // Create StirlingFileStub from metadata (no file data)
+        const stub: StirlingFileStub = {
+          id: record.id,
+          name: record.name,
+          type: record.type,
+          size: record.size,
+          lastModified: record.lastModified,
+          quickKey: record.quickKey,
+          thumbnailUrl: record.thumbnail,
+          isLeaf: record.isLeaf,
+          versionNumber: record.versionNumber,
+          originalFileId: record.originalFileId,
+          parentFileId: record.parentFileId,
+          toolHistory: record.toolHistory,
+          createdAt: Date.now() // Current session
+        };
+
+        resolve(stub);
+      };
+    });
+  }
+
+  /**
+   * Get all StirlingFileStubs (metadata only) - for FileManager browsing
+   */
+  async getAllStirlingFileStubs(): Promise<StirlingFileStub[]> {
     const db = await this.getDatabase();
 
     return new Promise((resolve, reject) => {
       const transaction = db.transaction([this.storeName], 'readonly');
       const store = transaction.objectStore(this.storeName);
       const request = store.openCursor();
-      const files: Omit<StoredFile, 'data'>[] = [];
+      const stubs: StirlingFileStub[] = [];
 
       request.onerror = () => reject(request.error);
       request.onsuccess = (event) => {
         const cursor = (event.target as IDBRequest).result;
         if (cursor) {
-          const storedFile = cursor.value;
-          // Only extract metadata, skip the data field
-          if (storedFile && storedFile.name && typeof storedFile.size === 'number') {
-            files.push({
-              id: storedFile.id,
-              name: storedFile.name,
-              type: storedFile.type,
-              size: storedFile.size,
-              lastModified: storedFile.lastModified,
-              thumbnail: storedFile.thumbnail
+          const record = cursor.value as StoredStirlingFileRecord;
+          if (record && record.name && typeof record.size === 'number') {
+            // Extract metadata only - no file data
+            stubs.push({
+              id: record.id,
+              name: record.name,
+              type: record.type,
+              size: record.size,
+              lastModified: record.lastModified,
+              quickKey: record.quickKey,
+              thumbnailUrl: record.thumbnail,
+              isLeaf: record.isLeaf,
+              versionNumber: record.versionNumber || 1,
+              originalFileId: record.originalFileId || record.id,
+              parentFileId: record.parentFileId,
+              toolHistory: record.toolHistory || [],
+              createdAt: Date.now()
             });
           }
           cursor.continue();
         } else {
-          // Metadata loaded efficiently without file data
-          resolve(files);
+          resolve(stubs);
         }
       };
     });
   }
 
   /**
-   * Delete a file from IndexedDB
+   * Get leaf StirlingFileStubs only - for unprocessed files
    */
-  async deleteFile(id: FileId): Promise<void> {
+  async getLeafStirlingFileStubs(): Promise<StirlingFileStub[]> {
+    const db = await this.getDatabase();
+
+    return new Promise((resolve, reject) => {
+      const transaction = db.transaction([this.storeName], 'readonly');
+      const store = transaction.objectStore(this.storeName);
+      const request = store.openCursor();
+      const leafStubs: StirlingFileStub[] = [];
+
+      request.onerror = () => reject(request.error);
+      request.onsuccess = (event) => {
+        const cursor = (event.target as IDBRequest).result;
+        if (cursor) {
+          const record = cursor.value as StoredStirlingFileRecord;
+          // Only include leaf files (default to true if undefined)
+          if (record && record.name && typeof record.size === 'number' && record.isLeaf !== false) {
+            leafStubs.push({
+              id: record.id,
+              name: record.name,
+              type: record.type,
+              size: record.size,
+              lastModified: record.lastModified,
+              quickKey: record.quickKey,
+              thumbnailUrl: record.thumbnail,
+              isLeaf: record.isLeaf,
+              versionNumber: record.versionNumber || 1,
+              originalFileId: record.originalFileId || record.id,
+              parentFileId: record.parentFileId,
+              toolHistory: record.toolHistory || [],
+              createdAt: Date.now()
+            });
+          }
+          cursor.continue();
+        } else {
+          resolve(leafStubs);
+        }
+      };
+    });
+  }
+
+  /**
+   * Delete StirlingFile - single operation, no sync issues
+   */
+  async deleteStirlingFile(id: FileId): Promise<void> {
     const db = await this.getDatabase();
 
     return new Promise((resolve, reject) => {
@@ -181,317 +275,7 @@ class FileStorageService {
   }
 
   /**
-   * Update the lastModified timestamp of a file (for most recently used sorting)
-   */
-  async touchFile(id: FileId): Promise<boolean> {
-    const db = await this.getDatabase();
-    return new Promise((resolve, reject) => {
-      const transaction = db.transaction([this.storeName], 'readwrite');
-      const store = transaction.objectStore(this.storeName);
-
-      const getRequest = store.get(id);
-      getRequest.onsuccess = () => {
-        const file = getRequest.result;
-        if (file) {
-          // Update lastModified to current timestamp
-          file.lastModified = Date.now();
-          const updateRequest = store.put(file);
-          updateRequest.onsuccess = () => resolve(true);
-          updateRequest.onerror = () => reject(updateRequest.error);
-        } else {
-          resolve(false); // File not found
-        }
-      };
-      getRequest.onerror = () => reject(getRequest.error);
-    });
-  }
-
-  /**
-   * Clear all stored files
-   */
-  async clearAll(): Promise<void> {
-    const db = await this.getDatabase();
-
-    return new Promise((resolve, reject) => {
-      const transaction = db.transaction([this.storeName], 'readwrite');
-      const store = transaction.objectStore(this.storeName);
-      const request = store.clear();
-
-      request.onerror = () => reject(request.error);
-      request.onsuccess = () => resolve();
-    });
-  }
-
-  /**
-   * Get storage statistics (only our IndexedDB usage)
-   */
-  async getStorageStats(): Promise<StorageStats> {
-    let used = 0;
-    let available = 0;
-    let quota: number | undefined;
-    let fileCount = 0;
-
-    try {
-      // Get browser quota for context
-      if ('storage' in navigator && 'estimate' in navigator.storage) {
-        const estimate = await navigator.storage.estimate();
-        quota = estimate.quota;
-        available = estimate.quota || 0;
-      }
-
-      // Calculate our actual IndexedDB usage from file metadata
-      const files = await this.getAllFileMetadata();
-      used = files.reduce((total, file) => total + (file?.size || 0), 0);
-      fileCount = files.length;
-
-      // Adjust available space
-      if (quota) {
-        available = quota - used;
-      }
-
-    } catch (error) {
-      console.warn('Could not get storage stats:', error);
-      // If we can't read metadata, database might be purged
-      used = 0;
-      fileCount = 0;
-    }
-
-    return {
-      used,
-      available,
-      fileCount,
-      quota
-    };
-  }
-
-  /**
-   * Get file count quickly without loading metadata
-   */
-  async getFileCount(): Promise<number> {
-    const db = await this.getDatabase();
-
-    return new Promise((resolve, reject) => {
-      const transaction = db.transaction([this.storeName], 'readonly');
-      const store = transaction.objectStore(this.storeName);
-      const request = store.count();
-
-      request.onerror = () => reject(request.error);
-      request.onsuccess = () => resolve(request.result);
-    });
-  }
-
-  /**
-   * Check all IndexedDB databases to see if files are in another version
-   */
-  async debugAllDatabases(): Promise<void> {
-    console.log('=== Checking All IndexedDB Databases ===');
-
-    if ('databases' in indexedDB) {
-      try {
-        const databases = await indexedDB.databases();
-        console.log('Found databases:', databases);
-
-        for (const dbInfo of databases) {
-          if (dbInfo.name?.includes('stirling') || dbInfo.name?.includes('pdf')) {
-            console.log(`Checking database: ${dbInfo.name} (version: ${dbInfo.version})`);
-            try {
-              const db = await new Promise<IDBDatabase>((resolve, reject) => {
-                const request = indexedDB.open(dbInfo.name!, dbInfo.version);
-                request.onsuccess = () => resolve(request.result);
-                request.onerror = () => reject(request.error);
-              });
-
-              console.log(`Database ${dbInfo.name} object stores:`, Array.from(db.objectStoreNames));
-              db.close();
-            } catch (error) {
-              console.error(`Failed to open database ${dbInfo.name}:`, error);
-            }
-          }
-        }
-      } catch (error) {
-        console.error('Failed to list databases:', error);
-      }
-    } else {
-      console.log('indexedDB.databases() not supported');
-    }
-
-    // Also check our specific database with different versions
-    for (let version = 1; version <= 3; version++) {
-      try {
-        console.log(`Trying to open ${this.dbConfig.name} version ${version}...`);
-        const db = await new Promise<IDBDatabase>((resolve, reject) => {
-          const request = indexedDB.open(this.dbConfig.name, version);
-          request.onsuccess = () => resolve(request.result);
-          request.onerror = () => reject(request.error);
-          request.onupgradeneeded = () => {
-            // Don't actually upgrade, just check
-            request.transaction?.abort();
-          };
-        });
-
-        console.log(`Version ${version} object stores:`, Array.from(db.objectStoreNames));
-
-        if (db.objectStoreNames.contains('files')) {
-          const transaction = db.transaction(['files'], 'readonly');
-          const store = transaction.objectStore('files');
-          const countRequest = store.count();
-          countRequest.onsuccess = () => {
-            console.log(`Version ${version} files store has ${countRequest.result} entries`);
-          };
-        }
-
-        db.close();
-      } catch (error) {
-        if (error instanceof Error) {
-          console.log(`Version ${version} not accessible:`, error.message);
-        }
-      }
-    }
-  }
-
-  /**
-   * Debug method to check what's actually in the database
-   */
-  async debugDatabaseContents(): Promise<void> {
-    const db = await this.getDatabase();
-
-    return new Promise((resolve, reject) => {
-      const transaction = db.transaction([this.storeName], 'readonly');
-      const store = transaction.objectStore(this.storeName);
-
-      // First try getAll to see if there's anything
-      const getAllRequest = store.getAll();
-      getAllRequest.onsuccess = () => {
-        console.log('=== Raw getAll() result ===');
-        console.log('Raw entries found:', getAllRequest.result.length);
-        getAllRequest.result.forEach((item, index) => {
-          console.log(`Raw entry ${index}:`, {
-            keys: Object.keys(item || {}),
-            id: item?.id,
-            name: item?.name,
-            size: item?.size,
-            type: item?.type,
-            hasData: !!item?.data,
-            dataSize: item?.data?.byteLength,
-            fullObject: item
-          });
-        });
-      };
-
-      // Then try cursor
-      const cursorRequest = store.openCursor();
-      console.log('=== IndexedDB Cursor Debug ===');
-      let count = 0;
-
-      cursorRequest.onerror = () => {
-        console.error('Cursor error:', cursorRequest.error);
-        reject(cursorRequest.error);
-      };
-
-      cursorRequest.onsuccess = (event) => {
-        const cursor = (event.target as IDBRequest).result;
-        if (cursor) {
-          count++;
-          const value = cursor.value;
-          console.log(`Cursor File ${count}:`, {
-            id: value?.id,
-            name: value?.name,
-            size: value?.size,
-            type: value?.type,
-            hasData: !!value?.data,
-            dataSize: value?.data?.byteLength,
-            hasThumbnail: !!value?.thumbnail,
-            allKeys: Object.keys(value || {})
-          });
-          cursor.continue();
-        } else {
-          console.log(`=== End Cursor Debug - Found ${count} files ===`);
-          resolve();
-        }
-      };
-    });
-  }
-
-  /**
-   * Convert StoredFile back to pure File object without mutations
-   * Returns a clean File object - use FileContext.addStoredFiles() for proper metadata handling
-   */
-  createFileFromStored(storedFile: StoredFile): File {
-    if (!storedFile || !storedFile.data) {
-      throw new Error('Invalid stored file: missing data');
-    }
-
-    if (!storedFile.name || typeof storedFile.size !== 'number') {
-      throw new Error('Invalid stored file: missing metadata');
-    }
-
-    const blob = new Blob([storedFile.data], { type: storedFile.type });
-    const file = new File([blob], storedFile.name, {
-      type: storedFile.type,
-      lastModified: storedFile.lastModified
-    });
-
-    // Use FileContext.addStoredFiles() to properly associate with metadata
-    return file;
-  }
-
-  /**
-   * Convert StoredFile to the format expected by FileContext.addStoredFiles()
-   * This is the recommended way to load stored files into FileContext
-   */
-  createFileWithMetadata(storedFile: StoredFile): { file: File; originalId: FileId; metadata: { thumbnail?: string } } {
-    const file = this.createFileFromStored(storedFile);
-
-    return {
-      file,
-      originalId: storedFile.id,
-      metadata: {
-        thumbnail: storedFile.thumbnail
-      }
-    };
-  }
-
-  /**
-   * Create blob URL for stored file
-   */
-  createBlobUrl(storedFile: StoredFile): string {
-    const blob = new Blob([storedFile.data], { type: storedFile.type });
-    return URL.createObjectURL(blob);
-  }
-
-  /**
-   * Get file data as ArrayBuffer for streaming/chunked processing
-   */
-  async getFileData(id: FileId): Promise<ArrayBuffer | null> {
-    try {
-      const storedFile = await this.getFile(id);
-      return storedFile ? storedFile.data : null;
-    } catch (error) {
-      console.warn(`Failed to get file data for ${id}:`, error);
-      return null;
-    }
-  }
-
-  /**
-   * Create a temporary blob URL that gets revoked automatically
-   */
-  async createTemporaryBlobUrl(id: FileId): Promise<string | null> {
-    const data = await this.getFileData(id);
-    if (!data) return null;
-
-    const blob = new Blob([data], { type: 'application/pdf' });
-    const url = URL.createObjectURL(blob);
-
-    // Auto-revoke after a short delay to free memory
-    setTimeout(() => {
-      URL.revokeObjectURL(url);
-    }, 10000); // 10 seconds
-
-    return url;
-  }
-
-  /**
-   * Update thumbnail for an existing file
+   * Update thumbnail for existing file
    */
   async updateThumbnail(id: FileId, thumbnail: string): Promise<boolean> {
     const db = await this.getDatabase();
@@ -503,13 +287,12 @@ class FileStorageService {
         const getRequest = store.get(id);
 
         getRequest.onsuccess = () => {
-          const storedFile = getRequest.result;
-          if (storedFile) {
-            storedFile.thumbnail = thumbnail;
-            const updateRequest = store.put(storedFile);
+          const record = getRequest.result as StoredStirlingFileRecord;
+          if (record) {
+            record.thumbnail = thumbnail;
+            const updateRequest = store.put(record);
 
             updateRequest.onsuccess = () => {
-              console.log('Thumbnail updated for file:', id);
               resolve(true);
             };
             updateRequest.onerror = () => {
@@ -533,31 +316,161 @@ class FileStorageService {
   }
 
   /**
-   * Check if storage quota is running low
+   * Clear all stored files
    */
-  async isStorageLow(): Promise<boolean> {
-    const stats = await this.getStorageStats();
-    if (!stats.quota) return false;
+  async clearAll(): Promise<void> {
+    const db = await this.getDatabase();
 
-    const usagePercent = stats.used / stats.quota;
-    return usagePercent > 0.8; // Consider low if over 80% used
+    return new Promise((resolve, reject) => {
+      const transaction = db.transaction([this.storeName], 'readwrite');
+      const store = transaction.objectStore(this.storeName);
+      const request = store.clear();
+
+      request.onerror = () => reject(request.error);
+      request.onsuccess = () => resolve();
+    });
   }
 
   /**
-   * Clean up old files if storage is low
+   * Get storage statistics
    */
-  async cleanupOldFiles(maxFiles: number = 50): Promise<void> {
-    const files = await this.getAllFileMetadata();
+  async getStorageStats(): Promise<StorageStats> {
+    let used = 0;
+    let available = 0;
+    let quota: number | undefined;
+    let fileCount = 0;
 
-    if (files.length <= maxFiles) return;
+    try {
+      // Get browser quota for context
+      if ('storage' in navigator && 'estimate' in navigator.storage) {
+        const estimate = await navigator.storage.estimate();
+        quota = estimate.quota;
+        available = estimate.quota || 0;
+      }
 
-    // Sort by last modified (oldest first)
-    files.sort((a, b) => a.lastModified - b.lastModified);
+      // Calculate our actual IndexedDB usage from file metadata
+      const stubs = await this.getAllStirlingFileStubs();
+      used = stubs.reduce((total, stub) => total + (stub?.size || 0), 0);
+      fileCount = stubs.length;
 
-    // Delete oldest files
-    const filesToDelete = files.slice(0, files.length - maxFiles);
-    for (const file of filesToDelete) {
-      await this.deleteFile(file.id);
+      // Adjust available space
+      if (quota) {
+        available = quota - used;
+      }
+
+    } catch (error) {
+      console.warn('Could not get storage stats:', error);
+      used = 0;
+      fileCount = 0;
+    }
+
+    return {
+      used,
+      available,
+      fileCount,
+      quota
+    };
+  }
+
+  /**
+   * Create blob URL for stored file data
+   */
+  async createBlobUrl(id: FileId): Promise<string | null> {
+    try {
+      const db = await this.getDatabase();
+
+      return new Promise((resolve, reject) => {
+        const transaction = db.transaction([this.storeName], 'readonly');
+        const store = transaction.objectStore(this.storeName);
+        const request = store.get(id);
+
+        request.onerror = () => reject(request.error);
+        request.onsuccess = () => {
+          const record = request.result as StoredStirlingFileRecord | undefined;
+          if (record) {
+            const blob = new Blob([record.data], { type: record.type });
+            const url = URL.createObjectURL(blob);
+            resolve(url);
+          } else {
+            resolve(null);
+          }
+        };
+      });
+    } catch (error) {
+      console.warn(`Failed to create blob URL for ${id}:`, error);
+      return null;
+    }
+  }
+
+  /**
+   * Mark a file as processed (no longer a leaf file)
+   * Used when a file becomes input to a tool operation
+   */
+  async markFileAsProcessed(fileId: FileId): Promise<boolean> {
+    try {
+      const db = await this.getDatabase();
+      const transaction = db.transaction([this.storeName], 'readwrite');
+      const store = transaction.objectStore(this.storeName);
+
+      const record = await new Promise<StoredStirlingFileRecord | undefined>((resolve, reject) => {
+        const request = store.get(fileId);
+        request.onsuccess = () => resolve(request.result);
+        request.onerror = () => reject(request.error);
+      });
+
+      if (!record) {
+        return false; // File not found
+      }
+
+      // Update the isLeaf flag to false
+      record.isLeaf = false;
+
+      await new Promise<void>((resolve, reject) => {
+        const request = store.put(record);
+        request.onsuccess = () => resolve();
+        request.onerror = () => reject(request.error);
+      });
+
+      return true;
+    } catch (error) {
+      console.error('Failed to mark file as processed:', error);
+      return false;
+    }
+  }
+
+  /**
+   * Mark a file as leaf (opposite of markFileAsProcessed)
+   * Used when promoting a file back to "recent" status
+   */
+  async markFileAsLeaf(fileId: FileId): Promise<boolean> {
+    try {
+      const db = await this.getDatabase();
+      const transaction = db.transaction([this.storeName], 'readwrite');
+      const store = transaction.objectStore(this.storeName);
+
+      const record = await new Promise<StoredStirlingFileRecord | undefined>((resolve, reject) => {
+        const request = store.get(fileId);
+        request.onsuccess = () => resolve(request.result);
+        request.onerror = () => reject(request.error);
+      });
+
+      if (!record) {
+        return false; // File not found
+      }
+
+      // Update the isLeaf flag to true
+      record.isLeaf = true;
+
+      await new Promise<void>((resolve, reject) => {
+        const request = store.put(record);
+        request.onsuccess = () => resolve();
+        request.onerror = () => reject(request.error);
+      });
+
+      return true;
+    } catch (error) {
+      console.error('Failed to mark file as leaf:', error);
+      return false;
     }
   }
 }

frontend/src/services/indexedDBManager.ts

@@ -87,45 +87,135 @@ class IndexedDBManager {
       request.onupgradeneeded = (event) => {
         const db = request.result;
         const oldVersion = event.oldVersion;
+        const transaction = request.transaction;
 
         console.log(`Upgrading ${config.name} from v${oldVersion} to v${config.version}`);
 
         // Create or update object stores
         config.stores.forEach(storeConfig => {
+          let store: IDBObjectStore | undefined;
+
           if (db.objectStoreNames.contains(storeConfig.name)) {
-            // Store exists - for now, just continue (could add migration logic here)
+            // Store exists - get reference for migration
             console.log(`Object store '${storeConfig.name}' already exists`);
-            return;
+            store = transaction?.objectStore(storeConfig.name);
+
+            // Add new indexes if they don't exist
+            if (storeConfig.indexes && store) {
+              storeConfig.indexes.forEach(indexConfig => {
+                if (!store?.indexNames.contains(indexConfig.name)) {
+                  store?.createIndex(
+                    indexConfig.name,
+                    indexConfig.keyPath,
+                    { unique: indexConfig.unique }
+                  );
+                  console.log(`Created index '${indexConfig.name}' on '${storeConfig.name}'`);
+                }
+              });
+            }
+          } else {
+            // Create new object store
+            const options: IDBObjectStoreParameters = {};
+            if (storeConfig.keyPath) {
+              options.keyPath = storeConfig.keyPath;
+            }
+            if (storeConfig.autoIncrement) {
+              options.autoIncrement = storeConfig.autoIncrement;
+            }
+
+            store = db.createObjectStore(storeConfig.name, options);
+            console.log(`Created object store '${storeConfig.name}'`);
+
+            // Create indexes
+            if (storeConfig.indexes) {
+              storeConfig.indexes.forEach(indexConfig => {
+                store?.createIndex(
+                  indexConfig.name,
+                  indexConfig.keyPath,
+                  { unique: indexConfig.unique }
+                );
+                console.log(`Created index '${indexConfig.name}' on '${storeConfig.name}'`);
+              });
+            }
           }
 
-          // Create new object store
-          const options: IDBObjectStoreParameters = {};
-          if (storeConfig.keyPath) {
-            options.keyPath = storeConfig.keyPath;
-          }
-          if (storeConfig.autoIncrement) {
-            options.autoIncrement = storeConfig.autoIncrement;
-          }
-
-          const store = db.createObjectStore(storeConfig.name, options);
-          console.log(`Created object store '${storeConfig.name}'`);
-
-          // Create indexes
-          if (storeConfig.indexes) {
-            storeConfig.indexes.forEach(indexConfig => {
-              store.createIndex(
-                indexConfig.name,
-                indexConfig.keyPath,
-                { unique: indexConfig.unique }
-              );
-              console.log(`Created index '${indexConfig.name}' on '${storeConfig.name}'`);
-            });
+          // Perform data migration for files database
+          if (config.name === 'stirling-pdf-files' && storeConfig.name === 'files' && store) {
+            this.migrateFileHistoryFields(store, oldVersion);
           }
         });
       };
     });
   }
 
+  /**
+   * Migrate existing file records to include new file history fields
+   */
+  private migrateFileHistoryFields(store: IDBObjectStore, oldVersion: number): void {
+    // Only migrate if upgrading from a version before file history was added (version < 3)
+    if (oldVersion >= 3) {
+      return;
+    }
+
+    console.log('Starting file history migration for existing records...');
+
+    const cursor = store.openCursor();
+    let migratedCount = 0;
+
+    cursor.onsuccess = (event) => {
+      const cursor = (event.target as IDBRequest).result;
+      if (cursor) {
+        const record = cursor.value;
+        let needsUpdate = false;
+
+        // Add missing file history fields with sensible defaults
+        if (record.isLeaf === undefined) {
+          record.isLeaf = true; // Existing files are unprocessed, should appear in recent files
+          needsUpdate = true;
+        }
+
+        if (record.versionNumber === undefined) {
+          record.versionNumber = 1; // Existing files are first version
+          needsUpdate = true;
+        }
+
+        if (record.originalFileId === undefined) {
+          record.originalFileId = record.id; // Existing files are their own root
+          needsUpdate = true;
+        }
+
+        if (record.parentFileId === undefined) {
+          record.parentFileId = undefined; // No parent for existing files
+          needsUpdate = true;
+        }
+
+        if (record.toolHistory === undefined) {
+          record.toolHistory = []; // No history for existing files
+          needsUpdate = true;
+        }
+
+        // Update the record if any fields were missing
+        if (needsUpdate) {
+          try {
+            cursor.update(record);
+            migratedCount++;
+          } catch (error) {
+            console.error('Failed to migrate record:', record.id, error);
+          }
+        }
+
+        cursor.continue();
+      } else {
+        // Migration complete
+        console.log(`File history migration completed. Migrated ${migratedCount} records.`);
+      }
+    };
+
+    cursor.onerror = (event) => {
+      console.error('File history migration failed:', (event.target as IDBRequest).error);
+    };
+  }
+
   /**
    * Get database connection (must be already opened)
    */
@@ -201,13 +291,16 @@ class IndexedDBManager {
 export const DATABASE_CONFIGS = {
   FILES: {
     name: 'stirling-pdf-files',
-    version: 2,
+    version: 3,
     stores: [{
       name: 'files',
       keyPath: 'id',
       indexes: [
         { name: 'name', keyPath: 'name', unique: false },
-        { name: 'lastModified', keyPath: 'lastModified', unique: false }
+        { name: 'lastModified', keyPath: 'lastModified', unique: false },
+        { name: 'originalFileId', keyPath: 'originalFileId', unique: false },
+        { name: 'parentFileId', keyPath: 'parentFileId', unique: false },
+        { name: 'versionNumber', keyPath: 'versionNumber', unique: false }
       ]
     }]
   } as DatabaseConfig,
@@ -219,7 +312,8 @@ export const DATABASE_CONFIGS = {
       name: 'drafts',
       keyPath: 'id'
     }]
-  } as DatabaseConfig
+  } as DatabaseConfig,
+
 } as const;
 
 export const indexedDBManager = IndexedDBManager.getInstance();

frontend/src/services/pdfExportService.ts

@@ -29,7 +29,7 @@ export class PDFExportService {
 
       // Load original PDF and create new document
       const originalPDFBytes = await pdfDocument.file.arrayBuffer();
-      const sourceDoc = await PDFLibDocument.load(originalPDFBytes);
+      const sourceDoc = await PDFLibDocument.load(originalPDFBytes, { ignoreEncryption: true });
       const blob = await this.createSingleDocument(sourceDoc, pagesToExport);
       const exportFilename = this.generateFilename(filename || pdfDocument.name);
 
@@ -86,7 +86,7 @@ export class PDFExportService {
     for (const [fileId, file] of sourceFiles) {
       try {
         const arrayBuffer = await file.arrayBuffer();
-        const doc = await PDFLibDocument.load(arrayBuffer);
+        const doc = await PDFLibDocument.load(arrayBuffer, { ignoreEncryption: true });
         loadedDocs.set(fileId, doc);
       } catch (error) {
         console.warn(`Failed to load source file ${fileId}:`, error);

frontend/src/tests/convert/ConvertIntegration.test.tsx

@@ -141,7 +141,7 @@ describe('Convert Tool Integration Tests', () => {
 
       // Verify hook state updates
       expect(result.current.downloadUrl).toBeTruthy();
-      expect(result.current.downloadFilename).toBe('test_converted.png');
+      expect(result.current.downloadFilename).toBe('test.png');
       expect(result.current.isLoading).toBe(false);
       expect(result.current.errorMessage).toBe(null);
     });
@@ -363,7 +363,7 @@ describe('Convert Tool Integration Tests', () => {
 
       // Verify hook state updates correctly
       expect(result.current.downloadUrl).toBeTruthy();
-      expect(result.current.downloadFilename).toBe('test_converted.csv');
+      expect(result.current.downloadFilename).toBe('test.csv');
       expect(result.current.isLoading).toBe(false);
       expect(result.current.errorMessage).toBe(null);
     });

frontend/src/theme/mantineTheme.ts

@@ -183,10 +183,10 @@ export const mantineTheme = createTheme({
         },
         option: {
           color: 'var(--text-primary)',
-          '&[data-hovered]': {
+          '&[dataHovered]': {
             backgroundColor: 'var(--hover-bg)',
           },
-          '&[data-selected]': {
+          '&[dataSelected]': {
             backgroundColor: 'var(--color-primary-100)',
             color: 'var(--color-primary-900)',
           },

frontend/src/tools/Split.tsx

@@ -1,10 +1,14 @@
 import { useTranslation } from "react-i18next";
 import { createToolFlow } from "../components/tools/shared/createToolFlow";
+import CardSelector from "../components/shared/CardSelector";
 import SplitSettings from "../components/tools/split/SplitSettings";
 import { useSplitParameters } from "../hooks/tools/split/useSplitParameters";
 import { useSplitOperation } from "../hooks/tools/split/useSplitOperation";
 import { useBaseTool } from "../hooks/tools/shared/useBaseTool";
+import { useSplitMethodTips } from "../components/tooltips/useSplitMethodTips";
+import { useSplitSettingsTips } from "../components/tooltips/useSplitSettingsTips";
 import { BaseToolProps, ToolComponent } from "../types/tool";
+import { type SplitMethod, METHOD_OPTIONS, type MethodOption } from "../constants/splitConstants";
 
 const Split = (props: BaseToolProps) => {
   const { t } = useTranslation();
@@ -16,6 +20,27 @@ const Split = (props: BaseToolProps) => {
     props
   );
 
+  const methodTips = useSplitMethodTips();
+  const settingsTips = useSplitSettingsTips(base.params.parameters.method);
+
+  // Get tooltip content for a specific method
+  const getMethodTooltip = (option: MethodOption) => {
+    const tooltipContent = useSplitSettingsTips(option.value);
+    return tooltipContent?.tips || [];
+  };
+
+  // Get the method name for the settings step title
+  const getSettingsTitle = () => {
+    if (!base.params.parameters.method) return t("split.steps.settings", "Settings");
+
+    const methodOption = METHOD_OPTIONS.find(option => option.value === base.params.parameters.method);
+    if (!methodOption) return t("split.steps.settings", "Settings");
+
+    const prefix = t(methodOption.prefixKey, "Split by");
+    const name = t(methodOption.nameKey, "Method Name");
+    return `${prefix} ${name}`;
+  };
+
   return createToolFlow({
     files: {
       selectedFiles: base.selectedFiles,
@@ -23,9 +48,25 @@ const Split = (props: BaseToolProps) => {
     },
     steps: [
       {
-        title: "Settings",
-        isCollapsed: base.settingsCollapsed,
+        title: t("split.steps.chooseMethod", "Choose Method"),
+        isCollapsed: !!base.params.parameters.method, // Collapse when method is selected
+        onCollapsedClick: () => base.params.updateParameter('method', '')
+        ,
+        tooltip: methodTips,
+        content: (
+          <CardSelector<SplitMethod, MethodOption>
+            options={METHOD_OPTIONS}
+            onSelect={(method) => base.params.updateParameter('method', method)}
+            disabled={base.endpointLoading}
+            getTooltipContent={getMethodTooltip}
+          />
+        ),
+      },
+      {
+        title: getSettingsTitle(),
+        isCollapsed: !base.params.parameters.method, // Collapsed until method selected
         onCollapsedClick: base.hasResults ? base.handleSettingsReset : undefined,
+        tooltip: settingsTips || undefined,
         content: (
           <SplitSettings
             parameters={base.params.parameters}

frontend/src/types/file.ts

@@ -7,55 +7,34 @@ declare const tag: unique symbol;
 export type FileId = string & { readonly [tag]: 'FileId' };
 
 /**
- * File metadata for efficient operations without loading full file data
- * Used by IndexedDBContext and FileContext for lazy file loading
+ * Tool operation metadata for history tracking
+ * Note: Parameters removed for security - sensitive data like passwords should not be stored in history
  */
-export interface FileMetadata {
+export interface ToolOperation {
+  toolName: string;
+  timestamp: number;
+}
+
+/**
+ * Base file metadata shared between storage and runtime layers
+ * Contains all common file properties and history tracking
+ */
+export interface BaseFileMetadata {
   id: FileId;
   name: string;
   type: string;
   size: number;
   lastModified: number;
-  thumbnail?: string;
-  isDraft?: boolean; // Marks files as draft versions
+  createdAt?: number; // When file was added to system
+
+  // File history tracking
+  isLeaf: boolean; // True if this file hasn't been processed yet
+  originalFileId: string; // Root file ID for grouping versions
+  versionNumber: number; // Version number in chain
+  parentFileId?: FileId; // Immediate parent file ID
+  toolHistory?: Array<{
+    toolName: string;
+    timestamp: number;
+  }>; // Tool chain for history tracking
+
 }
-
-export interface StorageConfig {
-  useIndexedDB: boolean;
-  maxFileSize: number; // Maximum size per file in bytes
-  maxTotalStorage: number; // Maximum total storage in bytes
-  warningThreshold: number; // Warning threshold (percentage 0-1)
-}
-
-export const defaultStorageConfig: StorageConfig = {
-  useIndexedDB: true,
-  maxFileSize: 100 * 1024 * 1024, // 100MB per file
-  maxTotalStorage: 1024 * 1024 * 1024, // 1GB default, will be updated dynamically
-  warningThreshold: 0.8, // Warn at 80% capacity
-};
-
-// Calculate and update storage limit: half of available storage or 10GB, whichever is smaller
-export const initializeStorageConfig = async (): Promise<StorageConfig> => {
-  const tenGB = 10 * 1024 * 1024 * 1024; // 10GB in bytes
-  const oneGB = 1024 * 1024 * 1024; // 1GB fallback
-
-  let maxTotalStorage = oneGB; // Default fallback
-
-  // Try to estimate available storage
-  if ('storage' in navigator && 'estimate' in navigator.storage) {
-    try {
-      const estimate = await navigator.storage.estimate();
-      if (estimate.quota) {
-        const halfQuota = estimate.quota / 2;
-        maxTotalStorage = Math.min(halfQuota, tenGB);
-      }
-    } catch (error) {
-      console.warn('Could not estimate storage quota, using 1GB default:', error);
-    }
-  }
-
-  return {
-    ...defaultStorageConfig,
-    maxTotalStorage
-  };
-};

frontend/src/types/fileContext.ts

@@ -3,7 +3,7 @@
  */
 
 import { PageOperation } from './pageEditor';
-import { FileId, FileMetadata } from './file';
+import { FileId, BaseFileMetadata } from './file';
 
 // Re-export FileId for convenience
 export type { FileId };
@@ -40,7 +40,6 @@ export interface ProcessedFilePage {
 export interface ProcessedFileMetadata {
   pages: ProcessedFilePage[];
   totalPages?: number;
-  thumbnailUrl?: string;
   lastProcessed?: number;
   [key: string]: any;
 }
@@ -52,16 +51,17 @@ export interface ProcessedFileMetadata {
  * separately in refs for memory efficiency. Supports multi-tool workflows
  * where files persist across tool operations.
  */
-export interface StirlingFileStub {
-  id: FileId;                    // UUID primary key for collision-free operations
-  name: string;                  // Display name for UI
-  size: number;                  // File size for progress indicators
-  type: string;                  // MIME type for format validation
-  lastModified: number;          // Original timestamp for deduplication
+/**
+ * StirlingFileStub - Runtime UI metadata for files in the active workbench session
+ *
+ * Contains UI display data and processing state. Actual File objects stored
+ * separately in refs for memory efficiency. Supports multi-tool workflows
+ * where files persist across tool operations.
+ */
+export interface StirlingFileStub extends BaseFileMetadata {
   quickKey?: string;             // Fast deduplication key: name|size|lastModified
   thumbnailUrl?: string;         // Generated thumbnail blob URL for visual display
   blobUrl?: string;             // File access blob URL for downloads/processing
-  createdAt?: number;           // When added to workbench for sorting
   processedFile?: ProcessedFileMetadata; // PDF page data and processing results
   insertAfterPageId?: string;   // Page ID after which this file should be inserted
   isPinned?: boolean;           // Protected from tool consumption (replace/remove)
@@ -107,6 +107,11 @@ export function isStirlingFile(file: File): file is StirlingFile {
 
 // Create a StirlingFile from a regular File object
 export function createStirlingFile(file: File, id?: FileId): StirlingFile {
+  // Check if file is already a StirlingFile to avoid property redefinition
+  if (isStirlingFile(file)) {
+    return file; // Already has fileId and quickKey properties
+  }
+
   const fileId = id || createFileId();
   const quickKey = createQuickKey(file);
 
@@ -151,9 +156,11 @@ export function isFileObject(obj: any): obj is File | StirlingFile {
 
 
 
-export function toStirlingFileStub(
+export function createNewStirlingFileStub(
   file: File,
-  id?: FileId
+  id?: FileId,
+  thumbnail?: string,
+  processedFileMetadata?: ProcessedFileMetadata
 ): StirlingFileStub {
   const fileId = id || createFileId();
   return {
@@ -162,8 +169,13 @@ export function toStirlingFileStub(
     size: file.size,
     type: file.type,
     lastModified: file.lastModified,
+    originalFileId: fileId,
     quickKey: createQuickKey(file),
-    createdAt: Date.now()
+    createdAt: Date.now(),
+    isLeaf: true, // New files are leaf nodes by default
+    versionNumber: 1, // New files start at version 1
+    thumbnailUrl: thumbnail,
+    processedFile: processedFileMetadata
   };
 }
 
@@ -209,7 +221,6 @@ export interface FileOperation {
   metadata?: {
     originalFileName?: string;
     outputFileNames?: string[];
-    parameters?: Record<string, any>;
     fileSize?: number;
     pageCount?: number;
     error?: string;
@@ -286,8 +297,7 @@ export type FileContextAction =
 export interface FileContextActions {
   // File management - lightweight actions only
   addFiles: (files: File[], options?: { insertAfterPageId?: string; selectFiles?: boolean }) => Promise<StirlingFile[]>;
-  addProcessedFiles: (filesWithThumbnails: Array<{ file: File; thumbnail?: string; pageCount?: number }>) => Promise<StirlingFile[]>;
-  addStoredFiles: (filesWithMetadata: Array<{ file: File; originalId: FileId; metadata: FileMetadata }>, options?: { selectFiles?: boolean }) => Promise<StirlingFile[]>;
+  addStirlingFileStubs: (stirlingFileStubs: StirlingFileStub[], options?: { insertAfterPageId?: string; selectFiles?: boolean }) => Promise<StirlingFile[]>;
   removeFiles: (fileIds: FileId[], deleteFromStorage?: boolean) => Promise<void>;
   updateStirlingFileStub: (id: FileId, updates: Partial<StirlingFileStub>) => void;
   reorderFiles: (orderedFileIds: FileId[]) => void;
@@ -299,7 +309,7 @@ export interface FileContextActions {
   unpinFile: (file: StirlingFile) => void;
 
   // File consumption (replace unpinned files with outputs)
-  consumeFiles: (inputFileIds: FileId[], outputFiles: File[]) => Promise<FileId[]>;
+  consumeFiles: (inputFileIds: FileId[], outputStirlingFiles: StirlingFile[], outputStirlingFileStubs: StirlingFileStub[]) => Promise<FileId[]>;
   undoConsumeFiles: (inputFiles: File[], inputStirlingFileStubs: StirlingFileStub[], outputFileIds: FileId[]) => Promise<void>;
   // Selection management
   setSelectedFiles: (fileIds: FileId[]) => void;

frontend/src/utils/downloadUtils.ts

@@ -1,4 +1,4 @@
-import { FileMetadata } from '../types/file';
+import { StirlingFileStub } from '../types/fileContext';
 import { fileStorage } from '../services/fileStorage';
 import { zipFileService } from '../services/zipFileService';
 
@@ -9,14 +9,14 @@ import { zipFileService } from '../services/zipFileService';
  */
 export function downloadBlob(blob: Blob, filename: string): void {
   const url = URL.createObjectURL(blob);
-  
+
   const link = document.createElement('a');
   link.href = url;
   link.download = filename;
   document.body.appendChild(link);
   link.click();
   document.body.removeChild(link);
-  
+
   // Clean up the blob URL
   URL.revokeObjectURL(url);
 }
@@ -26,23 +26,23 @@ export function downloadBlob(blob: Blob, filename: string): void {
  * @param file - The file object with storage information
  * @throws Error if file cannot be retrieved from storage
  */
-export async function downloadFileFromStorage(file: FileMetadata): Promise<void> {
+export async function downloadFileFromStorage(file: StirlingFileStub): Promise<void> {
   const lookupKey = file.id;
-  const storedFile = await fileStorage.getFile(lookupKey);
-  
-  if (!storedFile) {
+  const stirlingFile = await fileStorage.getStirlingFile(lookupKey);
+
+  if (!stirlingFile) {
     throw new Error(`File "${file.name}" not found in storage`);
   }
-  
-  const blob = new Blob([storedFile.data], { type: storedFile.type });
-  downloadBlob(blob, storedFile.name);
+
+  // StirlingFile is already a File object, just download it
+  downloadBlob(stirlingFile, stirlingFile.name);
 }
 
 /**
  * Downloads multiple files as individual downloads
  * @param files - Array of files to download
  */
-export async function downloadMultipleFiles(files: FileMetadata[]): Promise<void> {
+export async function downloadMultipleFiles(files: StirlingFileStub[]): Promise<void> {
   for (const file of files) {
     await downloadFileFromStorage(file);
   }
@@ -53,36 +53,33 @@ export async function downloadMultipleFiles(files: FileMetadata[]): Promise<void
  * @param files - Array of files to include in ZIP
  * @param zipFilename - Optional custom ZIP filename (defaults to timestamped name)
  */
-export async function downloadFilesAsZip(files: FileMetadata[], zipFilename?: string): Promise<void> {
+export async function downloadFilesAsZip(files: StirlingFileStub[], zipFilename?: string): Promise<void> {
   if (files.length === 0) {
     throw new Error('No files provided for ZIP download');
   }
 
   // Convert stored files to File objects
-  const fileObjects: File[] = [];
+  const filesToZip: File[] = [];
   for (const fileWithUrl of files) {
     const lookupKey = fileWithUrl.id;
-    const storedFile = await fileStorage.getFile(lookupKey);
-    
-    if (storedFile) {
-      const file = new File([storedFile.data], storedFile.name, {
-        type: storedFile.type,
-        lastModified: storedFile.lastModified
-      });
-      fileObjects.push(file);
+    const stirlingFile = await fileStorage.getStirlingFile(lookupKey);
+
+    if (stirlingFile) {
+      // StirlingFile is already a File object!
+      filesToZip.push(stirlingFile);
     }
   }
-  
-  if (fileObjects.length === 0) {
+
+  if (filesToZip.length === 0) {
     throw new Error('No valid files found in storage for ZIP download');
   }
 
   // Generate default filename if not provided
-  const finalZipFilename = zipFilename || 
+  const finalZipFilename = zipFilename ||
     `files-${new Date().toISOString().slice(0, 19).replace(/[:-]/g, '')}.zip`;
-  
+
   // Create and download ZIP
-  const { zipFile } = await zipFileService.createZipFromFiles(fileObjects, finalZipFilename);
+  const { zipFile } = await zipFileService.createZipFromFiles(filesToZip, finalZipFilename);
   downloadBlob(zipFile, finalZipFilename);
 }
 
@@ -94,7 +91,7 @@ export async function downloadFilesAsZip(files: FileMetadata[], zipFilename?: st
  * @param options - Download options
  */
 export async function downloadFiles(
-  files: FileMetadata[], 
+  files: StirlingFileStub[],
   options: {
     forceZip?: boolean;
     zipFilename?: string;
@@ -133,8 +130,8 @@ export function downloadFileObject(file: File, filename?: string): void {
  * @param mimeType - MIME type (defaults to text/plain)
  */
 export function downloadTextAsFile(
-  content: string, 
-  filename: string, 
+  content: string,
+  filename: string,
   mimeType: string = 'text/plain'
 ): void {
   const blob = new Blob([content], { type: mimeType });
@@ -149,4 +146,4 @@ export function downloadTextAsFile(
 export function downloadJsonAsFile(data: any, filename: string): void {
   const content = JSON.stringify(data, null, 2);
   downloadTextAsFile(content, filename, 'application/json');
-}
+}

frontend/src/utils/fileHistoryUtils.ts

@@ -0,0 +1,78 @@
+/**
+ * File History Utilities
+ *
+ * Helper functions for IndexedDB-based file history management.
+ * Handles file history operations and lineage tracking.
+ */
+import { StirlingFileStub } from '../types/fileContext';
+
+/**
+ * Group files by processing branches - each branch ends in a leaf file
+ * Returns Map<fileId, lineagePath[]> where fileId is the leaf and lineagePath is the path back to original
+ */
+export function groupFilesByOriginal(StirlingFileStubs: StirlingFileStub[]): Map<string, StirlingFileStub[]> {
+  const groups = new Map<string, StirlingFileStub[]>();
+
+  // Create a map for quick lookups
+  const fileMap = new Map<string, StirlingFileStub>();
+  for (const record of StirlingFileStubs) {
+    fileMap.set(record.id, record);
+  }
+
+  // Find leaf files (files that are not parents of any other files AND have version history)
+  // Original files (v0) should only be leaves if they have no processed versions at all
+  const leafFiles = StirlingFileStubs.filter(stub => {
+    const isParentOfOthers = StirlingFileStubs.some(otherStub => otherStub.parentFileId === stub.id);
+    const isOriginalOfOthers = StirlingFileStubs.some(otherStub => otherStub.originalFileId === stub.id);
+
+    // A file is a leaf if:
+    // 1. It's not a parent of any other files, AND
+    // 2. It has processing history (versionNumber > 0) OR it's not referenced as original by others
+    return !isParentOfOthers && (stub.versionNumber && stub.versionNumber > 0 || !isOriginalOfOthers);
+  });
+
+  // For each leaf file, build its complete lineage path back to original
+  for (const leafFile of leafFiles) {
+    const lineagePath: StirlingFileStub[] = [];
+    let currentFile: StirlingFileStub | undefined = leafFile;
+
+    // Trace back through parentFileId chain to build this specific branch
+    while (currentFile) {
+      lineagePath.push(currentFile);
+
+      // Move to parent file in this branch
+      let nextFile: StirlingFileStub | undefined = undefined;
+
+      if (currentFile.parentFileId) {
+        nextFile = fileMap.get(currentFile.parentFileId);
+      } else if (currentFile.originalFileId && currentFile.originalFileId !== currentFile.id) {
+        // For v1 files, the original file might be referenced by originalFileId
+        nextFile = fileMap.get(currentFile.originalFileId);
+      }
+
+      // Check for infinite loops before moving to next
+      if (nextFile && lineagePath.some(file => file.id === nextFile!.id)) {
+        break;
+      }
+
+      currentFile = nextFile;
+    }
+
+    // Sort lineage with latest version first (leaf at top)
+    lineagePath.sort((a, b) => (b.versionNumber || 0) - (a.versionNumber || 0));
+
+    // Use leaf file ID as the group key - each branch gets its own group
+    groups.set(leafFile.id, lineagePath);
+  }
+
+  return groups;
+}
+
+/**
+ * Check if a file has version history
+ */
+export function hasVersionHistory(fileStub: StirlingFileStub): boolean {
+  return !!(fileStub.originalFileId && fileStub.versionNumber && fileStub.versionNumber > 0);
+}
+
+

frontend/src/utils/toolOperationTracker.ts

@@ -6,7 +6,7 @@ import { FileOperation } from '../types/fileContext';
  */
 export const createOperation = <TParams = void>(
   operationType: string,
-  params: TParams,
+  _params: TParams,
   selectedFiles: File[]
 ): { operation: FileOperation; operationId: string; fileId: FileId } => {
   const operationId = `${operationType}-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
@@ -20,7 +20,6 @@ export const createOperation = <TParams = void>(
     status: 'pending',
     metadata: {
       originalFileName: selectedFiles[0]?.name,
-      parameters: params,
       fileSize: selectedFiles.reduce((sum, f) => sum + f.size, 0)
     }
   } as any /* FIX ME*/;

frontend/src/utils/toolResponseProcessor.ts

@@ -8,11 +8,12 @@ export type ResponseHandler = (blob: Blob, originalFiles: File[]) => Promise<Fil
  * - If a tool-specific responseHandler is provided, it is used.
  * - If responseHeaders provided and contains Content-Disposition, uses that filename.
  * - Otherwise, create a single file using the filePrefix + original name.
+ * - If filePrefix is empty, preserves the original filename.
  */
 export async function processResponse(
   blob: Blob,
   originalFiles: File[],
-  filePrefix: string,
+  filePrefix?: string,
   responseHandler?: ResponseHandler,
   responseHeaders?: Record<string, any>
 ): Promise<File[]> {
@@ -36,7 +37,13 @@ export async function processResponse(
 
   // Default behavior: use filePrefix + original name
   const original = originalFiles[0]?.name ?? 'result.pdf';
-  const name = `${filePrefix}${original}`;
+  // Only add prefix if it's not empty - this preserves original filenames for file history
+  const name = filePrefix ? `${filePrefix}${original}` : original;
   const type = blob.type || 'application/octet-stream';
-  return [new File([blob], name, { type })];
+
+  // File was modified by tool processing - set lastModified to current time
+  return [new File([blob], name, {
+    type,
+    lastModified: Date.now()
+  })];
 }