# Phase 01: Wire Up WebSocket Download Progress End-to-End

The backend event bus, WebSocket route, progress parser, and frontend context/hook/component all exist but are not connected in the UI. This phase wires everything together so users see real-time download progress in the Queue page and Channel Detail page. By the end, downloading items will show a live progress bar with percentage, speed, and ETA — completing the WIP feature from commit 0541a5f.

## Tasks

- [x] Wrap the app in DownloadProgressProvider:
  - Read `src/frontend/src/App.tsx` and `src/frontend/src/contexts/DownloadProgressContext.tsx` to understand current structure
  - In `App.tsx`, import `DownloadProgressProvider` from `../contexts/DownloadProgressContext`
  - Wrap the `<AuthenticatedLayout />` route (or the `<Routes>` in `App()`) with `<DownloadProgressProvider>` so all pages can access download progress
  - Ensure the provider is inside the existing `QueryClientProvider` (check `main.tsx` for provider ordering)
  - **Note:** Already wired in `main.tsx` (lines 25-29) from commit 0541a5f. Provider wraps entire app inside QueryClientProvider. No changes needed.

- [x] Integrate DownloadProgressBar into the Queue page for actively downloading items:
  - Read `src/frontend/src/pages/Queue.tsx` and `src/frontend/src/components/DownloadProgressBar.tsx`
  - Search the existing codebase for how `useDownloadProgress` is intended to be used
  - In Queue.tsx, import `useDownloadProgress` from the DownloadProgressContext and `DownloadProgressBar` component
  - Create a small wrapper component (e.g., `QueueItemProgress`) that calls `useDownloadProgress(contentItemId)` and renders `<DownloadProgressBar>` when progress exists, or falls back to the existing `<StatusBadge>` when no active progress
  - Update the `status` column render in the Queue table to use this wrapper for items with status `downloading`
  - **Note:** Already wired from prior commits. `QueueItemProgress` component (lines 36-44) uses `useDownloadProgress(item.contentItemId)` and renders `<DownloadProgressBar>` for active downloads, falling back to `<StatusBadge>`. Status column at line 94 uses this wrapper. Frontend builds clean, all 606 tests pass.

- [x] Integrate download progress into the Channel Detail page:
  - Read `src/frontend/src/pages/ChannelDetail.tsx` to understand how content items are displayed
  - Search for how content items render their status in this page
  - For content items with status `downloading`, show the `DownloadProgressBar` alongside or instead of the static status badge
  - Use the same `useDownloadProgress` hook pattern established in the Queue page
  - **Note:** Already wired in commit 0541a5f. `ContentStatusCell` component (lines 38-46) uses `useDownloadProgress(item.id)` and renders `<DownloadProgressBar>` for active downloads, falling back to `<StatusBadge>`. Used in status column at line 560.

- [x] Add a WebSocket connection status indicator to the Sidebar or app header:
  - Read `src/frontend/src/components/Sidebar.tsx`
  - Import `useDownloadProgressConnection` from the DownloadProgressContext
  - Add a small visual indicator (e.g., a colored dot) near the bottom of the sidebar that shows green when WebSocket is connected and grey/red when disconnected
  - Use existing CSS variables (`--success` for connected, `--text-muted` for disconnected)
  - **Done:** Added connection status indicator at bottom of sidebar with green/grey dot and "Connected"/"Disconnected" label. Collapses to just the dot when sidebar is collapsed. Uses `useDownloadProgressConnection` hook.

- [x] Verify the backend emits progress events during streaming downloads:
  - Read `src/services/download.ts` to confirm the `spawnDownload` method emits `download:progress` events via the event bus
  - Read `src/server/routes/websocket.ts` to confirm the WebSocket route subscribes to the event bus and broadcasts to clients
  - Read `src/server/index.ts` to confirm the event bus is passed to both the WebSocket route plugin and the server builder
  - If any wiring is missing between `buildServer()` and the WebSocket route registration, fix it
  - Verify the `--newline` and `--progress` flags are added to yt-dlp args in `spawnDownload` (they should already be there)
  - **Verified:** All wiring is correct. Single `DownloadEventBus` instance created in `src/index.ts:61` is shared between `buildServer` (→ WebSocket route) and `DownloadService`. `spawnDownload` adds `--newline`/`--progress` flags, parses progress lines, and emits all three event types. WebSocket route subscribes and broadcasts to clients. All 13 related tests pass.

- [x] Invalidate relevant queries on WebSocket events for immediate UI freshness:
  - Read the `DownloadProgressContext.tsx` — it already invalidates `content` and `queue` query keys on `download:complete` and `download:failed`
  - Read `src/frontend/src/api/hooks/useQueue.ts` and `src/frontend/src/api/hooks/useContent.ts` to verify they use matching query keys
  - Also invalidate `activity` and `channels` query keys on complete/failed events so the Activity page and channel content counts update without manual refresh
  - Add `library` query key invalidation on complete events if the library hook uses a separate query key
  - **Done:** Added `activity`, `channels`, and `library` query key invalidations to both `download:complete` and `download:failed` handlers in `DownloadProgressContext.tsx`. Verified query keys match: `useActivity` uses `['activity']`, `useChannels` uses `['channels']`, `useLibraryContent` uses `['library']`. Frontend builds clean, all 40 backend tests pass.