TalkEdit Copilot Instructions (Living Project Context)

Purpose: give AI assistants immediate, accurate context for this repository and define what must be kept in sync when the project evolves.

How To Use This File

This is a workspace instruction file for VS Code Chat/Copilot.
Treat this as the first source of truth for architecture and workflow expectations.
If your code changes make any section outdated, update this file in the same change.

Name: TalkEdit
Product: local-first, AI-powered, text-based audio/video editor.
Primary runtime: Tauri + React frontend + Python FastAPI backend.
Desktop only (Electron has been removed; Tauri is the exclusive desktop runtime).

Frontend: React 19, TypeScript, Vite, Tailwind, Zustand.
Desktop bridge: Tauri API (IPC commands via window.electronAPI polyfill in frontend/src/lib/tauri-bridge.ts for unified call-site interface).
Backend: FastAPI + Uvicorn (backend/main.py) with routers in backend/routers and core services in backend/services.
Media tooling: FFmpeg for edit/export and codec operations.
AI tooling: WhisperX/faster-whisper for transcription; provider layer supports OpenAI/Anthropic/Ollama.

frontend/src/components: editor UI (player, transcript, waveform, settings, export, AI panel).
frontend/src/store: Zustand state (editorStore, aiStore).
frontend/src/hooks: keyboard/video sync behavior.
backend/routers: API surface (/transcribe, /export, /ai/*, /captions, /audio/*).
backend/services: heavy operations (transcription, captioning, diarization, video editing, cleanup).
shared/project-schema.json: saved project schema contract.
src-tauri: Rust/Tauri host code and app configuration.

Use project virtualenvs where available (.venv312, .venv, or venv) for backend execution.

Keep router files thin; put heavy logic in backend/services.
Preserve response compatibility for existing frontend callers unless task explicitly allows API breakage.
Frontend uses unified window.electronAPI interface (Tauri-backed via tauri-bridge.ts); desktop APIs are implemented exclusively in Tauri.
Prefer small, focused edits over broad refactors.

Startup/rendering on Linux WebKit can regress when reintroducing remote fonts/CSP allowances; prefer local font assets.
Media URL handling between project load paths should remain consistent to avoid format-specific regressions (especially WAV/MP3 behavior).
Export pipeline changes must preserve caption modes (none, sidecar, burn-in) and audio enhancement behavior.

Word text correction (#015): Double-click any word in the transcript editor to edit its text inline. Press Enter to commit, Escape to cancel. State is updated in both words[] and segments[] arrays (segment text recomposed from updated words). Pure frontend; no backend changes needed.
Low-confidence word highlighting (#012): Words with confidence < threshold (default 0.6, configurable in Settings panel) render with an orange dotted underline. Tooltip shows exact confidence percentage. Threshold is persisted in localStorage key talkedit:confidenceThreshold.
Audio normalization (#018): New backend endpoint POST /audio/normalize in backend/routers/audio.py. Two-pass FFmpeg loudnorm (measure then apply) implemented in backend/services/audio_cleaner.py:normalize_audio(). Falls back to single-pass if measurement fails. Frontend UI in Export panel: target selector (YouTube -14, Spotify -16, Broadcast -23, etc.) with "Normalize" button.
Store: New updateWordText(index, text) action in editorStore.ts updates both words[] and recomputes segments[].text.
Settings panel: New confidence threshold slider (0–1 range).

When a task changes architecture, app wiring, commands, API shape, project schema, or major conventions, update this file before finishing.

Always update these sections if affected:

If behavior changed significantly, add a short note under a new Recent Changes section with: