diff --git a/frontend/src/components/editor/FileEditor.tsx b/frontend/src/components/editor/FileEditor.tsx
index 02c9a4cee..bd23b2ea0 100644
--- a/frontend/src/components/editor/FileEditor.tsx
+++ b/frontend/src/components/editor/FileEditor.tsx
@@ -27,9 +27,9 @@ interface FileItem {
 interface FileEditorProps {
   onOpenPageEditor?: (file: File) => void;
   onMergeFiles?: (files: File[]) => void;
-  sharedFiles?: any[];
-  setSharedFiles?: (files: any[]) => void;
-  preSelectedFiles?: any[];
+  sharedFiles?: { file: File; url: string }[];
+  setSharedFiles?: (files: { file: File; url: string }[]) => void;
+  preSelectedFiles?: { file: File; url: string }[];
   onClearPreSelection?: () => void;
 }
 
diff --git a/frontend/src/components/editor/PageEditor.tsx b/frontend/src/components/editor/PageEditor.tsx
index 0897266f5..9a84ab6d4 100644
--- a/frontend/src/components/editor/PageEditor.tsx
+++ b/frontend/src/components/editor/PageEditor.tsx
@@ -31,6 +31,7 @@ export interface PageEditorProps {
   setFile?: (file: { file: File; url: string } | null) => void;
   downloadUrl?: string | null;
   setDownloadUrl?: (url: string | null) => void;
+  sharedFiles?: { file: File; url: string }[];
 
   // Optional callbacks to expose internal functions
   onFunctionsReady?: (functions: {
diff --git a/frontend/src/components/editor/PageThumbnail.tsx b/frontend/src/components/editor/PageThumbnail.tsx
index b820742ae..89d0811b1 100644
--- a/frontend/src/components/editor/PageThumbnail.tsx
+++ b/frontend/src/components/editor/PageThumbnail.tsx
@@ -69,13 +69,6 @@ const PageThumbnail = ({
 }: PageThumbnailProps) => {
   return (
     <div
-      ref={(el) => {
-        if (el) {
-          pageRefs.current.set(page.id, el);
-        } else {
-          pageRefs.current.delete(page.id);
-        }
-      }}
       data-page-id={page.id}
       className={`
         ${styles.pageContainer}
diff --git a/frontend/src/components/fileManagement/FileManager.tsx b/frontend/src/components/fileManagement/FileManager.tsx
index e9904a708..8b6f91b33 100644
--- a/frontend/src/components/fileManagement/FileManager.tsx
+++ b/frontend/src/components/fileManagement/FileManager.tsx
@@ -22,6 +22,7 @@ interface FileManagerProps {
   allowMultiple?: boolean;
   setCurrentView?: (view: string) => void;
   onOpenFileEditor?: (selectedFiles?: FileWithUrl[]) => void;
+  onLoadFileToActive?: (file: File) => void;
 }
 
 const FileManager = ({
@@ -30,6 +31,7 @@ const FileManager = ({
   allowMultiple = true,
   setCurrentView,
   onOpenFileEditor,
+  onLoadFileToActive,
 }: FileManagerProps) => {
   const { t } = useTranslation();
   const [loading, setLoading] = useState(false);
@@ -210,28 +212,56 @@ const FileManager = ({
 
   const handleFileDoubleClick = async (file: FileWithUrl) => {
     try {
-      const url = await createBlobUrlForFile(file);
-      // Add file to the beginning of files array and switch to viewer
-      setFiles(prev => [{ file: file, url: url }, ...prev.filter(f => f.id !== file.id)]);
-      setCurrentView && setCurrentView("viewer");
+      // Reconstruct File object from storage and add to active files
+      if (onLoadFileToActive) {
+        const reconstructedFile = await reconstructFileFromStorage(file);
+        onLoadFileToActive(reconstructedFile);
+        setCurrentView && setCurrentView("viewer");
+      }
     } catch (error) {
-      console.error('Failed to create blob URL for file:', error);
+      console.error('Failed to load file to active set:', error);
       setNotification('Failed to open file. It may have been removed from storage.');
     }
   };
 
   const handleFileView = async (file: FileWithUrl) => {
     try {
-      const url = await createBlobUrlForFile(file);
-      // Add file to the beginning of files array and switch to viewer
-      setFiles(prev => [{ file: file, url: url }, ...prev.filter(f => f.id !== file.id)]);
-      setCurrentView && setCurrentView("viewer");
+      // Reconstruct File object from storage and add to active files
+      if (onLoadFileToActive) {
+        const reconstructedFile = await reconstructFileFromStorage(file);
+        onLoadFileToActive(reconstructedFile);
+        setCurrentView && setCurrentView("viewer");
+      }
     } catch (error) {
-      console.error('Failed to create blob URL for file:', error);
+      console.error('Failed to load file to active set:', error);
       setNotification('Failed to open file. It may have been removed from storage.');
     }
   };
 
+  const reconstructFileFromStorage = async (fileWithUrl: FileWithUrl): Promise<File> => {
+    // If it's already a regular file, return it
+    if (fileWithUrl instanceof File) {
+      return fileWithUrl;
+    }
+
+    // Reconstruct from IndexedDB
+    const arrayBuffer = await createBlobUrlForFile(fileWithUrl);
+    if (typeof arrayBuffer === 'string') {
+      // createBlobUrlForFile returned a blob URL, we need the actual data
+      const response = await fetch(arrayBuffer);
+      const data = await response.arrayBuffer();
+      return new File([data], fileWithUrl.name, {
+        type: fileWithUrl.type || 'application/pdf',
+        lastModified: fileWithUrl.lastModified || Date.now()
+      });
+    } else {
+      return new File([arrayBuffer], fileWithUrl.name, {
+        type: fileWithUrl.type || 'application/pdf',
+        lastModified: fileWithUrl.lastModified || Date.now()
+      });
+    }
+  };
+
   const handleFileEdit = (file: FileWithUrl) => {
     if (onOpenFileEditor) {
       onOpenFileEditor([file]);
@@ -309,8 +339,11 @@ const FileManager = ({
           subtitle="Add files to your storage for easy access across tools"
           sharedFiles={[]} // FileManager is the source, so no shared files
           onFilesSelect={(uploadedFiles) => {
-            // Handle multiple files
+            // Handle multiple files - add to storage AND active set
             handleDrop(uploadedFiles);
+            if (onLoadFileToActive && uploadedFiles.length > 0) {
+              uploadedFiles.forEach(onLoadFileToActive);
+            }
           }}
           allowMultiple={allowMultiple}
           accept={["application/pdf"]}
diff --git a/frontend/src/components/shared/FileUploadSelector.tsx b/frontend/src/components/shared/FileUploadSelector.tsx
index 929a3af49..18bfa282a 100644
--- a/frontend/src/components/shared/FileUploadSelector.tsx
+++ b/frontend/src/components/shared/FileUploadSelector.tsx
@@ -10,14 +10,14 @@ interface FileUploadSelectorProps {
   title?: string;
   subtitle?: string;
   showDropzone?: boolean;
-  
+
   // File handling
   sharedFiles?: any[];
   onFileSelect: (file: File) => void;
   onFilesSelect?: (files: File[]) => void;
   allowMultiple?: boolean;
   accept?: string[];
-  
+
   // Loading state
   loading?: boolean;
   disabled?: boolean;
@@ -40,7 +40,7 @@ const FileUploadSelector = ({
 
   const handleFileUpload = useCallback((uploadedFiles: File[]) => {
     if (uploadedFiles.length === 0) return;
-    
+
     if (allowMultiple && onFilesSelect) {
       onFilesSelect(uploadedFiles);
     } else {
@@ -50,7 +50,7 @@ const FileUploadSelector = ({
 
   const handleStorageSelection = useCallback((selectedFiles: File[]) => {
     if (selectedFiles.length === 0) return;
-    
+
     if (allowMultiple && onFilesSelect) {
       onFilesSelect(selectedFiles);
     } else {
@@ -81,13 +81,13 @@ const FileUploadSelector = ({
             disabled={disabled || sharedFiles.length === 0}
             loading={loading}
           >
-            Load from Storage ({sharedFiles.length} files available)
+            {loading ? "Loading..." : `Load from Storage (${sharedFiles.length} files available)`}
           </Button>
-          
+
           <Text size="md" c="dimmed">
             or
           </Text>
-          
+
           {showDropzone ? (
             <Dropzone
               onDrop={handleFileUpload}
@@ -115,8 +115,8 @@ const FileUploadSelector = ({
               disabled={disabled || loading}
               style={{ display: 'contents' }}
             >
-              <Button 
-                variant="outline" 
+              <Button
+                variant="outline"
                 size="lg"
                 disabled={disabled}
                 loading={loading}
@@ -139,4 +139,4 @@ const FileUploadSelector = ({
   );
 };
 
-export default FileUploadSelector;
\ No newline at end of file
+export default FileUploadSelector;
diff --git a/frontend/src/hooks/useFileWithUrl.ts b/frontend/src/hooks/useFileWithUrl.ts
new file mode 100644
index 000000000..d06cb73f2
--- /dev/null
+++ b/frontend/src/hooks/useFileWithUrl.ts
@@ -0,0 +1,39 @@
+import { useMemo } from 'react';
+
+/**
+ * Hook to convert a File object to { file: File; url: string } format
+ * Creates blob URL on-demand and handles cleanup
+ */
+export function useFileWithUrl(file: File | null): { file: File; url: string } | null {
+  return useMemo(() => {
+    if (!file) return null;
+    
+    const url = URL.createObjectURL(file);
+    
+    // Return object with cleanup function
+    const result = { file, url };
+    
+    // Store cleanup function for later use
+    (result as any)._cleanup = () => URL.revokeObjectURL(url);
+    
+    return result;
+  }, [file]);
+}
+
+/**
+ * Hook variant that returns cleanup function separately
+ */
+export function useFileWithUrlAndCleanup(file: File | null): {
+  fileObj: { file: File; url: string } | null;
+  cleanup: () => void;
+} {
+  return useMemo(() => {
+    if (!file) return { fileObj: null, cleanup: () => {} };
+    
+    const url = URL.createObjectURL(file);
+    const fileObj = { file, url };
+    const cleanup = () => URL.revokeObjectURL(url);
+    
+    return { fileObj, cleanup };
+  }, [file]);
+}
\ No newline at end of file
diff --git a/frontend/src/pages/HomePage.tsx b/frontend/src/pages/HomePage.tsx
index ea367253b..969623d80 100644
--- a/frontend/src/pages/HomePage.tsx
+++ b/frontend/src/pages/HomePage.tsx
@@ -1,5 +1,17 @@
-import React, { useState, useCallback } from "react";
-import { Box, Group, Container } from "@mantine/core";
+import React, { useState, useCallback, useEffect } from "react";
+import { useTranslation } from 'react-i18next';
+import { useSearchParams } from "react-router-dom";
+import { useToolParams } from "../hooks/useToolParams";
+import { useFileWithUrl } from "../hooks/useFileWithUrl";
+import { fileStorage } from "../services/fileStorage";
+import AddToPhotosIcon from "@mui/icons-material/AddToPhotos";
+import ContentCutIcon from "@mui/icons-material/ContentCut";
+import ZoomInMapIcon from "@mui/icons-material/ZoomInMap";
+import { Group, Paper, Box, Button, useMantineTheme, Container } from "@mantine/core";
+import { useRainbowThemeContext } from "../components/shared/RainbowThemeProvider";
+import rainbowStyles from '../styles/rainbow.module.css';
+
+import ToolPicker from "../components/tools/ToolPicker";
 import TopControls from "../components/shared/TopControls";
 import FileManager from "../components/fileManagement/FileManager";
 import FileEditor from "../components/editor/FileEditor";
@@ -7,26 +19,169 @@ import PageEditor from "../components/editor/PageEditor";
 import PageEditorControls from "../components/editor/PageEditorControls";
 import Viewer from "../components/viewer/Viewer";
 import FileUploadSelector from "../components/shared/FileUploadSelector";
+import SplitPdfPanel from "../tools/Split";
+import CompressPdfPanel from "../tools/Compress";
+import MergePdfPanel from "../tools/Merge";
+import ToolRenderer from "../components/tools/ToolRenderer";
+import QuickAccessBar from "../components/shared/QuickAccessBar";
+
+type ToolRegistryEntry = {
+  icon: React.ReactNode;
+  name: string;
+  component: React.ComponentType<any>;
+  view: string;
+};
+
+type ToolRegistry = {
+  [key: string]: ToolRegistryEntry;
+};
+
+// Base tool registry without translations
+const baseToolRegistry = {
+  split: { icon: <ContentCutIcon />, component: SplitPdfPanel, view: "viewer" },
+  compress: { icon: <ZoomInMapIcon />, component: CompressPdfPanel, view: "viewer" },
+  merge: { icon: <AddToPhotosIcon />, component: MergePdfPanel, view: "fileManager" },
+};
 
 export default function HomePage() {
-  const [files, setFiles] = useState([]); // Array of { file, url }
-  const [preSelectedFiles, setPreSelectedFiles] = useState([]);
-  const [currentView, setCurrentView] = useState("fileManager");
-  const [sidebarsVisible, setSidebarsVisible] = useState(true);
-  const [downloadUrl, setDownloadUrl] = useState(null);
-  const [pageEditorFunctions, setPageEditorFunctions] = useState(null);
+  const { t } = useTranslation();
+  const [searchParams] = useSearchParams();
+  const theme = useMantineTheme();
+  const { isRainbowMode } = useRainbowThemeContext();
 
-  // Handle file selection from upload
-  const handleFileSelect = useCallback((file) => {
-    const fileObj = { file, url: URL.createObjectURL(file) };
-    setFiles([fileObj]);
+  // Core app state
+  const [selectedToolKey, setSelectedToolKey] = useState<string>(searchParams.get("t") || "split");
+  const [currentView, setCurrentView] = useState<string>(searchParams.get("v") || "viewer");
+
+  // File state separation
+  const [storedFiles, setStoredFiles] = useState<any[]>([]); // IndexedDB files (FileManager)
+  const [activeFiles, setActiveFiles] = useState<File[]>([]); // Active working set (persisted)
+  const [preSelectedFiles, setPreSelectedFiles] = useState([]);
+
+  const [downloadUrl, setDownloadUrl] = useState<string | null>(null);
+  const [sidebarsVisible, setSidebarsVisible] = useState(true);
+  const [leftPanelView, setLeftPanelView] = useState<'toolPicker' | 'toolContent'>('toolPicker');
+  const [readerMode, setReaderMode] = useState(false);
+
+  // Page editor functions
+  const [pageEditorFunctions, setPageEditorFunctions] = useState<any>(null);
+
+  // URL parameter management
+  const { toolParams, updateParams } = useToolParams(selectedToolKey, currentView);
+
+  // Persist active files across reloads
+  useEffect(() => {
+    // Save active files to localStorage (just metadata)
+    const activeFileData = activeFiles.map(file => ({
+      name: file.name,
+      size: file.size,
+      type: file.type,
+      lastModified: file.lastModified
+    }));
+    localStorage.setItem('activeFiles', JSON.stringify(activeFileData));
+  }, [activeFiles]);
+
+  // Load stored files from IndexedDB on mount
+  useEffect(() => {
+    const loadStoredFiles = async () => {
+      try {
+        const files = await fileStorage.getAllFiles();
+        setStoredFiles(files);
+      } catch (error) {
+        console.warn('Failed to load stored files:', error);
+      }
+    };
+    loadStoredFiles();
   }, []);
 
+  // Restore active files on load
+  useEffect(() => {
+    const restoreActiveFiles = async () => {
+      try {
+        const savedFileData = JSON.parse(localStorage.getItem('activeFiles') || '[]');
+        if (savedFileData.length > 0) {
+          // TODO: Reconstruct files from IndexedDB when fileStorage is available
+          console.log('Would restore active files:', savedFileData);
+        }
+      } catch (error) {
+        console.warn('Failed to restore active files:', error);
+      }
+    };
+    restoreActiveFiles();
+  }, []);
+
+  const toolRegistry: ToolRegistry = {
+    split: { ...baseToolRegistry.split, name: t("home.split.title", "Split PDF") },
+    compress: { ...baseToolRegistry.compress, name: t("home.compressPdfs.title", "Compress PDF") },
+    merge: { ...baseToolRegistry.merge, name: t("home.merge.title", "Merge PDFs") },
+  };
+
+  // Handle tool selection
+  const handleToolSelect = useCallback(
+    (id: string) => {
+      setSelectedToolKey(id);
+      if (toolRegistry[id]?.view) setCurrentView(toolRegistry[id].view);
+      setLeftPanelView('toolContent'); // Switch to tool content view when a tool is selected
+      setReaderMode(false); // Exit reader mode when selecting a tool
+    },
+    [toolRegistry]
+  );
+
+  // Handle quick access actions
+  const handleQuickAccessTools = useCallback(() => {
+    setLeftPanelView('toolPicker');
+    setReaderMode(false);
+  }, []);
+
+  const handleReaderToggle = useCallback(() => {
+    setReaderMode(!readerMode);
+  }, [readerMode]);
+
+  // Update URL when view changes
+  const handleViewChange = useCallback((view: string) => {
+    setCurrentView(view);
+    const params = new URLSearchParams(window.location.search);
+    params.set('view', view);
+    const newUrl = `${window.location.pathname}?${params.toString()}`;
+    window.history.replaceState({}, '', newUrl);
+  }, []);
+
+  // Active file management
+  const addToActiveFiles = useCallback((file: File) => {
+    setActiveFiles(prev => {
+      // Avoid duplicates based on name and size
+      const exists = prev.some(f => f.name === file.name && f.size === file.size);
+      if (exists) return prev;
+      return [file, ...prev];
+    });
+  }, []);
+
+  const removeFromActiveFiles = useCallback((file: File) => {
+    setActiveFiles(prev => prev.filter(f => !(f.name === file.name && f.size === file.size)));
+  }, []);
+
+  const setCurrentActiveFile = useCallback((file: File) => {
+    setActiveFiles(prev => {
+      const filtered = prev.filter(f => !(f.name === file.name && f.size === file.size));
+      return [file, ...filtered];
+    });
+  }, []);
+
+  // Handle file selection from upload (adds to active files)
+  const handleFileSelect = useCallback((file: File) => {
+    addToActiveFiles(file);
+  }, [addToActiveFiles]);
+
   // Handle opening file editor with selected files
   const handleOpenFileEditor = useCallback((selectedFiles) => {
     setPreSelectedFiles(selectedFiles || []);
-    setCurrentView("fileEditor");
-  }, []);
+    handleViewChange("fileEditor");
+  }, [handleViewChange]);
+
+  const selectedTool = toolRegistry[selectedToolKey];
+
+  // Convert current active file to format expected by Viewer/PageEditor
+  const currentFileWithUrl = useFileWithUrl(activeFiles[0] || null);
 
   return (
     <Group
@@ -34,6 +189,86 @@ export default function HomePage() {
       gap={0}
       className="min-h-screen w-screen overflow-hidden flex-nowrap flex"
     >
+      {/* Quick Access Bar */}
+      <QuickAccessBar
+        onToolsClick={handleQuickAccessTools}
+        onReaderToggle={handleReaderToggle}
+        selectedToolKey={selectedToolKey}
+        toolRegistry={toolRegistry}
+        leftPanelView={leftPanelView}
+        readerMode={readerMode}
+      />
+
+      {/* Left: Tool Picker OR Selected Tool Panel */}
+      <div
+        className={`h-screen z-sticky flex flex-col ${isRainbowMode ? rainbowStyles.rainbowPaper : ''} overflow-hidden`}
+        style={{
+          backgroundColor: 'var(--bg-surface)',
+          borderRight: '1px solid var(--border-subtle)',
+          width: sidebarsVisible && !readerMode ? '25vw' : '0px',
+          minWidth: sidebarsVisible && !readerMode ? '300px' : '0px',
+          maxWidth: sidebarsVisible && !readerMode ? '450px' : '0px',
+          transition: 'width 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94), min-width 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94), max-width 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94)',
+          padding: sidebarsVisible && !readerMode ? '1rem' : '0rem'
+        }}
+      >
+          <div
+            style={{
+              opacity: sidebarsVisible && !readerMode ? 1 : 0,
+              transition: 'opacity 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94)',
+              height: '100%',
+              display: 'flex',
+              flexDirection: 'column'
+            }}
+          >
+            {leftPanelView === 'toolPicker' ? (
+              // Tool Picker View
+              <div className="flex-1 flex flex-col">
+                <ToolPicker
+                  selectedToolKey={selectedToolKey}
+                  onSelect={handleToolSelect}
+                  toolRegistry={toolRegistry}
+                />
+              </div>
+            ) : (
+              // Selected Tool Content View
+              <div className="flex-1 flex flex-col">
+                {/* Back button */}
+                <div className="mb-4">
+                  <Button
+                    variant="subtle"
+                    size="sm"
+                    onClick={() => setLeftPanelView('toolPicker')}
+                    className="text-sm"
+                  >
+                    ← Back to Tools
+                  </Button>
+                </div>
+
+                {/* Tool title */}
+                <div className="mb-4">
+                  <h2 className="text-lg font-semibold">{selectedTool?.name}</h2>
+                </div>
+
+                {/* Tool content */}
+                <div className="flex-1 min-h-0">
+                  <ToolRenderer
+                    selectedToolKey={selectedToolKey}
+                    selectedTool={selectedTool}
+                    pdfFile={activeFiles[0] || null}
+                    files={activeFiles}
+                    downloadUrl={downloadUrl}
+                    setDownloadUrl={setDownloadUrl}
+                    toolParams={toolParams}
+                    updateParams={updateParams}
+                  />
+                </div>
+              </div>
+            )}
+          </div>
+      </div>
+
+      {/* Main View */}
       <Box
         className="flex-1 h-screen min-w-80 relative flex flex-col"
         style={{
@@ -43,89 +278,105 @@ export default function HomePage() {
         {/* Top Controls */}
         <TopControls
           currentView={currentView}
-          setCurrentView={setCurrentView}
+          setCurrentView={handleViewChange}
         />
         {/* Main content area */}
-        <Box className="flex-1 min-h-0 margin-top-200 relative z-10">
-          {currentView === "fileManager" ? (
-            <FileManager
-              files={files}
-              setFiles={setFiles}
-              setCurrentView={setCurrentView}
-              onOpenFileEditor={handleOpenFileEditor}
-            />
-          ) : (currentView !== "fileManager") && !files[0] ? (
-            <Container size="lg" p="xl" h="100%" style={{ display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
-              <FileUploadSelector
-                title={currentView === "viewer" ? "Select a PDF to view" : "Select a PDF to edit"}
-                subtitle="Choose a file from storage or upload a new PDF"
-                sharedFiles={files}
-                onFileSelect={handleFileSelect}
-                allowMultiple={false}
-                accept={["application/pdf"]}
-                loading={false}
+          <Box className="flex-1 min-h-0 margin-top-200 relative z-10">
+            {currentView === "fileManager" ? (
+              <FileManager
+                files={storedFiles}
+                setFiles={setStoredFiles}
+                setCurrentView={handleViewChange}
+                onOpenFileEditor={handleOpenFileEditor}
+                onLoadFileToActive={addToActiveFiles}
               />
-            </Container>
-          ) : currentView === "fileEditor" ? (
-            <FileEditor
-              sharedFiles={files}
-              setSharedFiles={setFiles}
-              preSelectedFiles={preSelectedFiles}
-              onClearPreSelection={() => setPreSelectedFiles([])}
-              onOpenPageEditor={(file) => {
-                const fileObj = { file, url: URL.createObjectURL(file) };
-                setFiles([fileObj]);
-                setCurrentView("pageEditor");
-              }}
-              onMergeFiles={(filesToMerge) => {
-                setFiles(filesToMerge.map(f => ({ file: f, url: URL.createObjectURL(f) })));
-                setCurrentView("viewer");
-              }}
-            />
-          ) : currentView === "viewer" ? (
-            <Viewer
-              pdfFile={files[0]}
-              setPdfFile={(fileObj) => setFiles([fileObj])}
-              sidebarsVisible={sidebarsVisible}
-              setSidebarsVisible={setSidebarsVisible}
-            />
-          ) : currentView === "pageEditor" ? (
-            <>
-              <PageEditor
-                file={files[0]}
-                setFile={(fileObj) => setFiles([fileObj])}
-                downloadUrl={downloadUrl}
-                setDownloadUrl={setDownloadUrl}
-                onFunctionsReady={setPageEditorFunctions}
-                sharedFiles={files}
-              />
-              {files[0] && pageEditorFunctions && (
-                <PageEditorControls
-                  onClosePdf={pageEditorFunctions.closePdf}
-                  onUndo={pageEditorFunctions.handleUndo}
-                  onRedo={pageEditorFunctions.handleRedo}
-                  canUndo={pageEditorFunctions.canUndo}
-                  canRedo={pageEditorFunctions.canRedo}
-                  onRotate={pageEditorFunctions.handleRotate}
-                  onDelete={pageEditorFunctions.handleDelete}
-                  onSplit={pageEditorFunctions.handleSplit}
-                  onExportSelected={() => pageEditorFunctions.showExportPreview(true)}
-                  onExportAll={() => pageEditorFunctions.showExportPreview(false)}
-                  exportLoading={pageEditorFunctions.exportLoading}
-                  selectionMode={pageEditorFunctions.selectionMode}
-                  selectedPages={pageEditorFunctions.selectedPages}
+            ) : (currentView != "fileManager") && !activeFiles[0] ? (
+              <Container size="lg" p="xl" h="100%" style={{ display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
+                <FileUploadSelector
+                  title={currentView === "viewer" ? "Select a PDF to view" : "Select a PDF to edit"}
+                  subtitle="Choose a file from storage or upload a new PDF"
+                  sharedFiles={storedFiles}
+                  onFileSelect={(file) => {
+                    addToActiveFiles(file);
+                  }}
+                  allowMultiple={false}
+                  accept={["application/pdf"]}
+                  loading={false}
                 />
-              )}
-            </>
-          ) : (
-            <FileManager
-              files={files}
-              setFiles={setFiles}
-              setCurrentView={setCurrentView}
-              onOpenFileEditor={handleOpenFileEditor}
-            />
-          )}
-        </Box>
+              </Container>
+            ) : currentView === "fileEditor" ? (
+              <FileEditor
+                sharedFiles={activeFiles}
+                setSharedFiles={setActiveFiles}
+                preSelectedFiles={preSelectedFiles}
+                onClearPreSelection={() => setPreSelectedFiles([])}
+                onOpenPageEditor={(file) => {
+                  setCurrentActiveFile(file);
+                  handleViewChange("pageEditor");
+                }}
+                onMergeFiles={(filesToMerge) => {
+                  // Add merged files to active set
+                  filesToMerge.forEach(addToActiveFiles);
+                  handleViewChange("viewer");
+                }}
+              />
+            ) :  currentView === "viewer" ? (
+              <Viewer
+                pdfFile={currentFileWithUrl}
+                setPdfFile={(fileObj) => {
+                  if (fileObj) {
+                    setCurrentActiveFile(fileObj.file);
+                  } else {
+                    setActiveFiles([]);
+                  }
+                }}
+                sidebarsVisible={sidebarsVisible}
+                setSidebarsVisible={setSidebarsVisible}
+              />
+            ) : currentView === "pageEditor" ? (
+              <>
+                <PageEditor
+                  file={currentFileWithUrl}
+                  setFile={(fileObj) => {
+                    if (fileObj) {
+                      setCurrentActiveFile(fileObj.file);
+                    } else {
+                      setActiveFiles([]);
+                    }
+                  }}
+                  downloadUrl={downloadUrl}
+                  setDownloadUrl={setDownloadUrl}
+                  onFunctionsReady={setPageEditorFunctions}
+                  sharedFiles={activeFiles}
+                />
+                {activeFiles[0] && pageEditorFunctions && (
+                  <PageEditorControls
+                    onClosePdf={pageEditorFunctions.closePdf}
+                    onUndo={pageEditorFunctions.handleUndo}
+                    onRedo={pageEditorFunctions.handleRedo}
+                    canUndo={pageEditorFunctions.canUndo}
+                    canRedo={pageEditorFunctions.canRedo}
+                    onRotate={pageEditorFunctions.handleRotate}
+                    onDelete={pageEditorFunctions.handleDelete}
+                    onSplit={pageEditorFunctions.handleSplit}
+                    onExportSelected={() => pageEditorFunctions.showExportPreview(true)}
+                    onExportAll={() => pageEditorFunctions.showExportPreview(false)}
+                    exportLoading={pageEditorFunctions.exportLoading}
+                    selectionMode={pageEditorFunctions.selectionMode}
+                    selectedPages={pageEditorFunctions.selectedPages}
+                  />
+                )}
+              </>
+            ) : (
+              <FileManager
+                files={storedFiles}
+                setFiles={setStoredFiles}
+                setCurrentView={handleViewChange}
+                onOpenFileEditor={handleOpenFileEditor}
+                onLoadFileToActive={addToActiveFiles}
+              />
+            )}
+          </Box>
       </Box>
     </Group>
   );