nexus/.planning/phases/37-web-chat-voice-ui/37-02-SUMMARY.md

phase	plan	subsystem	tags	dependency_graph	tech_stack	key_files	decisions	metrics
37-web-chat-voice-ui	02	ui/voice-recording	voice vad waveform hooks components	requires provides affects 37-01 VoiceMicButton VoiceWaveform useVadRecorder useVoiceMode encodeWav ChatInput.tsx	added patterns @ricky0123/vad-react (useMicVAD) Web Audio API (AnalyserNode) WAV PCM encoding VAD auto-stop recording canvas animation loop optimistic settings update	created modified ui/src/lib/encodeWav.ts ui/src/hooks/useVadRecorder.ts ui/src/hooks/useVoiceMode.ts ui/src/components/VoiceWaveform.tsx ui/src/components/VoiceMicButton.tsx	useVadRecorder requests a separate MediaStream ref for VoiceWaveform AnalyserNode — useMicVAD manages its own stream internally but VoiceWaveform needs an explicit stream reference AudioContext not closed on cleanup — reused across recording cycles to avoid repeated unlock prompts WAV encoder clamps Float32Array samples to [-1, 1] then converts to int16 — matches Whisper 16kHz mono PCM input format VoiceMicButton uses three separate JSX returns rather than conditional rendering within one — cleaner state machines, avoids aria-label switching bugs	duration_seconds completed_date tasks_completed tasks_total files_created files_modified 102 2026-04-04 2 2 5 0

Phase 37 Plan 02: Voice Recording Components Summary

One-liner: VAD-powered voice recording pipeline — WAV encoder, useMicVAD hook with auto-stop + transcription, voice mode settings hook, canvas waveform, and three-state VoiceMicButton.

Tasks Completed

Task	Name	Commit	Files
1	encodeWav utility and useVadRecorder + useVoiceMode hooks	3676c9c3	ui/src/lib/encodeWav.ts, ui/src/hooks/useVadRecorder.ts, ui/src/hooks/useVoiceMode.ts
2	VoiceWaveform canvas component and VoiceMicButton	bdb2f770	ui/src/components/VoiceWaveform.tsx, ui/src/components/VoiceMicButton.tsx

What Was Built

encodeWav (ui/src/lib/encodeWav.ts)

Standard 44-byte WAV header encoder (RIFF/WAVE/fmt/data chunks). Converts Float32Array to PCM mono 16-bit WAV Blob at 16kHz. Clamps samples to [-1, 1] before int16 conversion. Whisper-compatible format.

useVadRecorder (ui/src/hooks/useVadRecorder.ts)

Wraps useMicVAD from @ricky0123/vad-react. Configuration: startOnLoad: false, baseAssetPath: "/", onnxWASMBasePath: "/", positiveSpeechThreshold: 0.8, minSpeechFrames: 5. On onSpeechEnd: pauses VAD, encodes to WAV, POSTs FormData to /api/transcribe, calls onTranscript if text length >= 2. Exposes mediaStream ref for VoiceWaveform AnalyserNode.

useVoiceMode (ui/src/hooks/useVoiceMode.ts)

Loads voiceMode from GET /api/nexus/settings on mount. Provides setMode() with optimistic update that PATCHes /api/nexus/settings and reverts on error. Three mode values: text | voice_input | full_voice.

VoiceWaveform (ui/src/components/VoiceWaveform.tsx)

Canvas element (80x32px). When stream and active are truthy: creates AudioContext, MediaStreamSource, AnalyserNode (fftSize=64, 32 bins). Draws 20 bars per frame (skipping every other bin), bar width 2px + gap 2px, height proportional to frequency magnitude. Color from CSS --primary variable. Cancels animation and disconnects source on cleanup.

VoiceMicButton (ui/src/components/VoiceMicButton.tsx)

Three visual states:

• idle: Mic icon, ghost variant, h-8 w-8, aria-label="Start voice input"
• recording: VoiceWaveform inside button, ring-2 ring-primary class, aria-label="Recording — speak now"
• processing: Loader2 animate-spin, disabled, aria-label="Transcribing..."

Deviations from Plan

None — plan executed exactly as written.

Known Stubs

None. All 5 files are fully implemented with real logic, no placeholder values.

Self-Check: PASSED

All 5 files confirmed on disk. Both task commits (3676c9c3, bdb2f770) confirmed in git history.