fix(editor): harden timeline playback and export

package.json

@@ -33,6 +33,7 @@
     "routes": "tsr generate",
     "test": "vp test",
     "test:run": "vp test run",
+    "test:editor-hardening": "vp test run src/features/timeline/components/timeline-content.test.tsx src/features/timeline/components/timeline-item/use-timeline-item-pointer-handlers.test.tsx src/features/timeline/hooks/shortcuts/use-clipboard-shortcuts.test.tsx src/features/timeline/hooks/shortcuts/use-playback-shortcuts.test.tsx src/features/timeline/stores/export-snapshot.test.ts src/features/export/components/export-dialog.test.tsx src/features/export/hooks/client-render-source.test.ts src/features/export/hooks/use-client-render.test.tsx src/features/preview/workers/consume-video-samples.test.ts src/features/preview/utils/media-resolver.test.ts src/features/preview/hooks/use-preview-media-resolution.test.tsx src/features/preview/components/source-composition.generation.test.tsx src/features/preview/components/video-preview.sync.test.tsx src/infrastructure/browser/blob-url-manager.test.ts",
     "test:preview-sync": "vp test run src/features/preview/components/video-preview.sync.test.tsx",
     "test:preview-sync:stress": "node scripts/preview-sync-stress.mjs --runs 20",
     "test:coverage": "vp test run --coverage",

src/features/export/components/export-dialog.test.tsx

@@ -9,6 +9,69 @@ const mockDownloadVideo = vi.fn()
 const mockResetState = vi.fn()
 const mockGetSupportedCodecs = vi.fn<(...args: unknown[]) => Promise<ClientCodec[]>>()
 
+const { mainSequence, selectedSequence, mockGetExportableSequence } = vi.hoisted(() => {
+  const sequence = (id: string | null, name: string, itemId: string) => {
+    const trackId = `track-${itemId}`
+    const item = {
+      id: itemId,
+      trackId,
+      type: 'text' as const,
+      from: 0,
+      durationInFrames: 30,
+      label: name,
+      text: name,
+      color: '#ffffff',
+    }
+    return {
+      id,
+      name,
+      tracks: [
+        {
+          id: trackId,
+          name: 'V1',
+          kind: 'video' as const,
+          height: 60,
+          locked: false,
+          visible: true,
+          muted: false,
+          solo: false,
+          order: 0,
+          items: [item],
+        },
+      ],
+      items: [item],
+      transitions: [],
+      keyframes: [],
+      fps: 30,
+      width: 1920,
+      height: 1080,
+      backgroundColor: '#000000',
+      masterBusDb: 0,
+      durationFrames: 30,
+      inPoint: null,
+      outPoint: null,
+      markers: [],
+    }
+  }
+
+  const main = sequence(null, 'Main Timeline', 'main-title')
+  const selected = sequence('agent-cut', 'Agent Cut', 'agent-title')
+  return {
+    mainSequence: main,
+    selectedSequence: selected,
+    mockGetExportableSequence: vi.fn((id: string | null) => (id === selected.id ? selected : main)),
+  }
+})
+
+vi.mock('@/features/export/deps/timeline-compositions', () => ({
+  getActiveExportSequenceId: () => null,
+  getExportableSequence: mockGetExportableSequence,
+  listExportableSequences: () => [
+    { id: null, name: mainSequence.name },
+    { id: selectedSequence.id, name: selectedSequence.name },
+  ],
+}))
+
 vi.mock('../hooks/use-client-render', () => ({
   useClientRender: () => ({
     isExporting: false,
@@ -115,4 +178,22 @@ describe('ExportDialog', () => {
     const h265Option = await screen.findByRole('option', { name: /H\.265/i })
     expect(h265Option).toHaveAttribute('data-disabled')
   })
+
+  it('passes the selected sequence snapshot to direct export', async () => {
+    mockGetSupportedCodecs.mockResolvedValue(['avc'])
+    mockStartExport.mockResolvedValue(undefined)
+
+    render(<ExportDialog open onClose={() => {}} />)
+
+    fireEvent.keyDown(screen.getByLabelText('Sequence'), { key: 'ArrowDown' })
+    fireEvent.click(await screen.findByRole('option', { name: selectedSequence.name }))
+
+    const exportButton = screen.getByRole('button', { name: 'Export Video' })
+    await waitFor(() => expect(exportButton).not.toBeDisabled())
+    fireEvent.click(exportButton)
+
+    await waitFor(() => {
+      expect(mockStartExport).toHaveBeenCalledWith(expect.any(Object), selectedSequence)
+    })
+  })
 })

src/features/export/components/export-dialog.tsx

@@ -394,8 +394,7 @@ export function ExportDialog({ open, onClose, onOpenRenderQueue }: ExportDialogP
     const reversedClipIds = new Set(
       items
         .filter(
-          (item) =>
-            (item.type === 'video' || item.type === 'audio') && item.isReversed === true,
+          (item) => (item.type === 'video' || item.type === 'audio') && item.isReversed === true,
         )
         .map((item) => item.id),
     )
@@ -643,8 +642,9 @@ export function ExportDialog({ open, onClose, onOpenRenderQueue }: ExportDialogP
 
   // Start export
   const handleStartExport = async () => {
+    const seq = captureSelection()
     setView('progress')
-    await startExport(buildExtendedSettings())
+    await startExport(buildExtendedSettings(), seq)
   }
 
   // The active render range for a sequence (whole timeline unless in/out set).
@@ -1574,8 +1574,7 @@ export function ExportDialog({ open, onClose, onOpenRenderQueue }: ExportDialogP
                 </div>
                 <div className="flex items-center justify-between text-sm gap-2">
                   <span className="text-muted-foreground truncate">
-                    {status === 'preparing' &&
-                      (progressMessage ?? t('export.progress.preparing'))}
+                    {status === 'preparing' && (progressMessage ?? t('export.progress.preparing'))}
                     {status === 'rendering' && t('export.progress.rendering')}
                     {status === 'encoding' && t('export.progress.encoding')}
                     {status === 'finalizing' && t('export.progress.finalizing')}

src/features/export/hooks/client-render-source.test.ts

@@ -0,0 +1,51 @@
+// @vitest-environment node
+
+import { describe, expect, it } from 'vite-plus/test'
+import type { ExportableSequence } from '@/features/export/deps/timeline-compositions'
+import { resolveClientRenderSource } from './client-render-source'
+
+function makeSequence(overrides: Partial<ExportableSequence> = {}): ExportableSequence {
+  return {
+    id: 'selected',
+    name: 'Selected',
+    tracks: [],
+    items: [],
+    transitions: [],
+    keyframes: [],
+    fps: 24,
+    width: 1280,
+    height: 720,
+    masterBusDb: -3,
+    durationFrames: 0,
+    inPoint: null,
+    outPoint: null,
+    markers: [],
+    ...overrides,
+  }
+}
+
+describe('resolveClientRenderSource', () => {
+  it('preserves an explicitly unset selected-sequence range and EQ', () => {
+    const sequence = makeSequence({ busAudioEq: undefined, backgroundColor: undefined })
+    const result = resolveClientRenderSource(
+      sequence,
+      makeSequence({ id: null, inPoint: 30, outPoint: 90 }),
+      {
+        busAudioEq: { enabled: true, lowGainDb: 4, midGainDb: 2, highGainDb: 3 },
+        masterBusDb: 6,
+      },
+      { width: 1920, height: 1080, backgroundColor: '#ff0000' },
+    )
+
+    expect(result).toMatchObject({
+      fps: 24,
+      inPoint: null,
+      outPoint: null,
+      busAudioEq: undefined,
+      masterBusDb: -3,
+      backgroundColor: undefined,
+      width: 1280,
+      height: 720,
+    })
+  })
+})

src/features/export/hooks/client-render-source.ts

@@ -0,0 +1,43 @@
+import type { ExportableSequence } from '@/features/export/deps/timeline-compositions'
+import { DEFAULT_PROJECT_HEIGHT, DEFAULT_PROJECT_WIDTH } from '@/shared/projects/defaults'
+
+type TimelineRenderSource = Pick<
+  ExportableSequence,
+  'tracks' | 'items' | 'transitions' | 'fps' | 'inPoint' | 'outPoint' | 'keyframes'
+>
+
+type PlaybackRenderSource = Pick<ExportableSequence, 'busAudioEq' | 'masterBusDb'>
+
+interface ProjectRenderMetadata {
+  width?: number
+  height?: number
+  backgroundColor?: string
+}
+
+/**
+ * Select one complete render source. Once a sequence snapshot is supplied,
+ * its nullable/optional values are authoritative too: an unset range or EQ
+ * must not inherit state from whichever timeline happens to be active.
+ */
+export function resolveClientRenderSource(
+  sequence: ExportableSequence | undefined,
+  timeline: TimelineRenderSource,
+  playback: PlaybackRenderSource,
+  projectMetadata: ProjectRenderMetadata | undefined,
+) {
+  const source = sequence ?? timeline
+  return {
+    tracks: source.tracks,
+    items: source.items,
+    transitions: source.transitions,
+    fps: source.fps,
+    inPoint: source.inPoint,
+    outPoint: source.outPoint,
+    keyframes: source.keyframes,
+    busAudioEq: sequence ? sequence.busAudioEq : playback.busAudioEq,
+    masterBusDb: sequence ? sequence.masterBusDb : playback.masterBusDb,
+    backgroundColor: sequence ? sequence.backgroundColor : projectMetadata?.backgroundColor,
+    width: sequence?.width ?? projectMetadata?.width ?? DEFAULT_PROJECT_WIDTH,
+    height: sequence?.height ?? projectMetadata?.height ?? DEFAULT_PROJECT_HEIGHT,
+  }
+}