fix(export): make PNG exports adapt to active theme (JhaSourav07#822)

Author: JhaSourav07

components/dashboard/ShareSheet.test.tsx

@@ -74,6 +74,7 @@ describe('ShareSheet', () => {
 
   afterEach(() => {
     vi.restoreAllMocks();
+    document.documentElement.classList.remove('dark');
   });
 
   it('does not render when isOpen is false', () => {
@@ -195,7 +196,10 @@ describe('ShareSheet', () => {
     );
   });
 
-  it('handles Download PNG action', async () => {
+  it('handles Download PNG action in dark mode', async () => {
+    // Add 'dark' class to document.documentElement
+    document.documentElement.classList.add('dark');
+
     render(<ShareSheet {...defaultProps} />);
 
     // Create a mock document element to satisfy the selector
@@ -207,7 +211,41 @@ describe('ShareSheet', () => {
     fireEvent.click(downloadButton!);
 
     const { toPng } = await import('html-to-image');
-    expect(toPng).toHaveBeenCalled();
+    expect(toPng).toHaveBeenLastCalledWith(
+      expect.any(HTMLElement),
+      expect.objectContaining({
+        backgroundColor: '#050505',
+      })
+    );
+
+    await waitFor(() => {
+      expect(screen.getByText('Downloaded!')).toBeDefined();
+    });
+
+    document.body.removeChild(mockRoot);
+  });
+
+  it('handles Download PNG action in light mode', async () => {
+    // Ensure 'dark' class is NOT on document.documentElement
+    document.documentElement.classList.remove('dark');
+
+    render(<ShareSheet {...defaultProps} />);
+
+    // Create a mock document element to satisfy the selector
+    const mockRoot = document.createElement('div');
+    mockRoot.id = 'dashboard-root';
+    document.body.appendChild(mockRoot);
+
+    const downloadButton = screen.getByText('Download as PNG').closest('button');
+    fireEvent.click(downloadButton!);
+
+    const { toPng } = await import('html-to-image');
+    expect(toPng).toHaveBeenLastCalledWith(
+      expect.any(HTMLElement),
+      expect.objectContaining({
+        backgroundColor: '#ffffff',
+      })
+    );
 
     await waitFor(() => {
       expect(screen.getByText('Downloaded!')).toBeDefined();

hooks/useShareActions.ts

@@ -80,10 +80,12 @@ export function useShareActions(
         document.getElementById('dashboard-root') ??
         document.querySelector<HTMLElement>('[data-dashboard]') ??
         document.body;
+      const isDark =
+        typeof document !== 'undefined' && document.documentElement.classList.contains('dark');
       const dataUrl = await toPng(node, {
         quality: 0.95,
         pixelRatio: 2,
-        backgroundColor: '#050505',
+        backgroundColor: isDark ? '#050505' : '#ffffff',
         filter: (el) => {
           if (el instanceof HTMLElement) {
             if (el.id === 'share-sheet-overlay') return false;