From 697cb6a179864a96c77f778b6738a58148f1a695 Mon Sep 17 00:00:00 2001
From: James Brunton <james@stirlingpdf.com>
Date: Wed, 10 Sep 2025 16:53:31 +0100
Subject: [PATCH] Add tests

---
 .../AdjustPageScaleSettings.test.tsx          |  64 ++++++++
 .../useAdjustPageScaleParameters.test.ts      | 142 ++++++++++++++++++
 2 files changed, 206 insertions(+)
 create mode 100644 frontend/src/components/tools/adjustPageScale/AdjustPageScaleSettings.test.tsx
 create mode 100644 frontend/src/hooks/tools/adjustPageScale/useAdjustPageScaleParameters.test.ts

diff --git a/frontend/src/components/tools/adjustPageScale/AdjustPageScaleSettings.test.tsx b/frontend/src/components/tools/adjustPageScale/AdjustPageScaleSettings.test.tsx
new file mode 100644
index 000000000..d71655cdc
--- /dev/null
+++ b/frontend/src/components/tools/adjustPageScale/AdjustPageScaleSettings.test.tsx
@@ -0,0 +1,64 @@
+import { describe, expect, test, vi, beforeEach } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import { MantineProvider } from '@mantine/core';
+import AdjustPageScaleSettings from './AdjustPageScaleSettings';
+import { AdjustPageScaleParameters, PageSize } from '../../../hooks/tools/adjustPageScale/useAdjustPageScaleParameters';
+
+// Mock useTranslation with predictable return values
+const mockT = vi.fn((key: string, fallback?: string) => fallback || `mock-${key}`);
+vi.mock('react-i18next', () => ({
+  useTranslation: () => ({ t: mockT })
+}));
+
+// Wrapper component to provide Mantine context
+const TestWrapper = ({ children }: { children: React.ReactNode }) => (
+  <MantineProvider>{children}</MantineProvider>
+);
+
+describe('AdjustPageScaleSettings', () => {
+  const defaultParameters: AdjustPageScaleParameters = {
+    scaleFactor: 1.0,
+    pageSize: PageSize.KEEP,
+  };
+
+  const mockOnParameterChange = vi.fn();
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  test('should render without crashing', () => {
+    render(
+      <TestWrapper>
+        <AdjustPageScaleSettings
+          parameters={defaultParameters}
+          onParameterChange={mockOnParameterChange}
+        />
+      </TestWrapper>
+    );
+
+    // Basic render test - component renders without throwing
+    expect(screen.getByText('Scale Factor')).toBeInTheDocument();
+    expect(screen.getByText('Target Page Size')).toBeInTheDocument();
+  });
+
+  test('should render with custom parameters', () => {
+    const customParameters: AdjustPageScaleParameters = {
+      scaleFactor: 2.5,
+      pageSize: PageSize.A4,
+    };
+
+    render(
+      <TestWrapper>
+        <AdjustPageScaleSettings
+          parameters={customParameters}
+          onParameterChange={mockOnParameterChange}
+        />
+      </TestWrapper>
+    );
+
+    // Component renders successfully with custom parameters
+    expect(screen.getByText('Scale Factor')).toBeInTheDocument();
+    expect(screen.getByText('Target Page Size')).toBeInTheDocument();
+  });
+});
diff --git a/frontend/src/hooks/tools/adjustPageScale/useAdjustPageScaleParameters.test.ts b/frontend/src/hooks/tools/adjustPageScale/useAdjustPageScaleParameters.test.ts
new file mode 100644
index 000000000..d68cdd861
--- /dev/null
+++ b/frontend/src/hooks/tools/adjustPageScale/useAdjustPageScaleParameters.test.ts
@@ -0,0 +1,142 @@
+import { describe, expect, test } from 'vitest';
+import { renderHook, act } from '@testing-library/react';
+import { useAdjustPageScaleParameters, defaultParameters, PageSize, AdjustPageScaleParametersHook } from './useAdjustPageScaleParameters';
+
+describe('useAdjustPageScaleParameters', () => {
+  test('should initialize with default parameters', () => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    expect(result.current.parameters).toStrictEqual(defaultParameters);
+    expect(result.current.parameters.scaleFactor).toBe(1.0);
+    expect(result.current.parameters.pageSize).toBe(PageSize.KEEP);
+  });
+
+  test.each([
+    { paramName: 'scaleFactor' as const, value: 0.5 },
+    { paramName: 'scaleFactor' as const, value: 2.0 },
+    { paramName: 'scaleFactor' as const, value: 10.0 },
+    { paramName: 'pageSize' as const, value: PageSize.A4 },
+    { paramName: 'pageSize' as const, value: PageSize.LETTER },
+    { paramName: 'pageSize' as const, value: PageSize.LEGAL },
+  ])('should update parameter $paramName to $value', ({ paramName, value }) => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    act(() => {
+      result.current.updateParameter(paramName, value);
+    });
+
+    expect(result.current.parameters[paramName]).toBe(value);
+  });
+
+  test('should reset parameters to defaults', () => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    // First, change some parameters
+    act(() => {
+      result.current.updateParameter('scaleFactor', 2.5);
+      result.current.updateParameter('pageSize', PageSize.A3);
+    });
+
+    expect(result.current.parameters.scaleFactor).toBe(2.5);
+    expect(result.current.parameters.pageSize).toBe(PageSize.A3);
+
+    // Then reset
+    act(() => {
+      result.current.resetParameters();
+    });
+
+    expect(result.current.parameters).toStrictEqual(defaultParameters);
+  });
+
+  test('should return correct endpoint name', () => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    expect(result.current.getEndpointName()).toBe('scale-pages');
+  });
+
+  test.each([
+    {
+      description: 'with default parameters',
+      setup: () => {},
+      expected: true
+    },
+    {
+      description: 'with valid scale factor 0.1',
+      setup: (hook: AdjustPageScaleParametersHook) => {
+        hook.updateParameter('scaleFactor', 0.1);
+      },
+      expected: true
+    },
+    {
+      description: 'with valid scale factor 10.0',
+      setup: (hook: AdjustPageScaleParametersHook) => {
+        hook.updateParameter('scaleFactor', 10.0);
+      },
+      expected: true
+    },
+    {
+      description: 'with A4 page size',
+      setup: (hook: AdjustPageScaleParametersHook) => {
+        hook.updateParameter('pageSize', PageSize.A4);
+      },
+      expected: true
+    },
+    {
+      description: 'with invalid scale factor 0',
+      setup: (hook: AdjustPageScaleParametersHook) => {
+        hook.updateParameter('scaleFactor', 0);
+      },
+      expected: false
+    },
+    {
+      description: 'with negative scale factor',
+      setup: (hook: AdjustPageScaleParametersHook) => {
+        hook.updateParameter('scaleFactor', -0.5);
+      },
+      expected: false
+    }
+  ])('should validate parameters correctly $description', ({ setup, expected }) => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    act(() => {
+      setup(result.current);
+    });
+
+    expect(result.current.validateParameters()).toBe(expected);
+  });
+
+  test('should handle all PageSize enum values', () => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    Object.values(PageSize).forEach(pageSize => {
+      act(() => {
+        result.current.updateParameter('pageSize', pageSize);
+      });
+
+      expect(result.current.parameters.pageSize).toBe(pageSize);
+      expect(result.current.validateParameters()).toBe(true);
+    });
+  });
+
+  test('should handle scale factor edge cases', () => {
+    const { result } = renderHook(() => useAdjustPageScaleParameters());
+
+    // Test very small valid scale factor
+    act(() => {
+      result.current.updateParameter('scaleFactor', 0.01);
+    });
+    expect(result.current.validateParameters()).toBe(true);
+
+    // Test scale factor just above zero
+    act(() => {
+      result.current.updateParameter('scaleFactor', 0.001);
+    });
+    expect(result.current.validateParameters()).toBe(true);
+
+    // Test exactly zero (invalid)
+    act(() => {
+      result.current.updateParameter('scaleFactor', 0);
+    });
+    expect(result.current.validateParameters()).toBe(false);
+  });
+});