meh

tasks/audio-playback-fix/01-fix-volume-speed-controls.md

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+# 01. Fix volume and speed controls in audio backends
+
+meta:
+  id: audio-playback-fix-01
+  feature: audio-playback-fix
+  priority: P1
+  depends_on: []
+  tags: [implementation, backend-fix, testing-required]
+
+objective:
+- Fix non-functional volume and speed controls in audio player backends (mpv, ffplay, afplay)
+- Implement proper error handling and validation for volume/speed commands
+- Ensure commands are successfully received and applied by the audio player
+
+deliverables:
+- Fixed `MpvBackend.setVolume()` and `MpvBackend.setSpeed()` methods with proper IPC command validation
+- Enhanced `AfplayBackend.setVolume()` and `AfplayBackend.setSpeed()` for runtime changes
+- Added command response validation in all backends
+- Unit tests for volume and speed control methods
+
+steps:
+- Step 1: Analyze current IPC implementation in MpvBackend (lines 206-223)
+- Step 2: Implement proper response validation for setVolume and setSpeed IPC commands
+- Step 3: Fix afplay backend to apply volume/speed changes at runtime (currently only on next play)
+- Step 4: Add error handling and logging for failed volume/speed commands
+- Step 5: Add unit tests in `src/utils/audio-player.test.ts` for volume/speed methods
+- Step 6: Verify volume changes apply immediately and persist across playback
+- Step 7: Verify speed changes apply immediately and persist across playback
+
+tests:
+- Unit:
+  - Test MpvBackend.setVolume() sends correct IPC command and receives valid response
+  - Test MpvBackend.setSpeed() sends correct IPC command and receives valid response
+  - Test AfplayBackend.setVolume() applies volume immediately
+  - Test AfplayBackend.setSpeed() applies speed immediately
+  - Test volume clamp values (0-1 range)
+  - Test speed clamp values (0.25-3 range)
+- Integration:
+  - Test volume control through Player component UI
+  - Test speed control through Player component UI
+  - Test volume/speed changes persist across pause/resume cycles
+  - Test volume/speed changes persist across track changes
+
+acceptance_criteria:
+- Volume slider in Player component changes volume in real-time
+- Speed controls in Player component change playback speed in real-time
+- Volume changes are visible in system audio output
+- Speed changes are immediately reflected in playback rate
+- No errors logged when changing volume or speed
+- Volume/speed settings persist when restarting the app
+
+validation:
+- Run `bun test src/utils/audio-player.test.ts` to verify unit tests pass
+- Test volume control using Up/Down arrow keys in Player
+- Test speed control using 'S' key in Player
+- Verify volume level is visible in PlaybackControls component
+- Verify speed level is visible in PlaybackControls component
+- Check console logs for any IPC errors
+
+notes:
+- mpv backend uses JSON IPC over Unix socket - need to validate response format
+- afplay backend needs to restart process for volume/speed changes (current behavior)
+- ffplay backend doesn't support runtime volume/speed changes (document limitation)
+- Volume and speed state is stored in backend class properties and should be updated on successful commands
+- Reference: src/utils/audio-player.ts lines 206-223 (mpv send method), lines 789-791 (afplay setVolume), lines 793-795 (afplay setSpeed)