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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+ROA AUTO is a multi-tenant auto service management PWA. The architecture is **offline-first**: the Vue 3 frontend uses wa-sqlite (WebAssembly SQLite) running entirely in the browser as `:memory:`, with a sync engine that pulls from and pushes to the FastAPI backend. All business data lives locally in the browser's in-memory SQLite DB and is periodically synced.
+
+## Development Commands
+
+### Backend (FastAPI)
+```bash
+cd backend
+source .venv/bin/activate
+uvicorn app.main:app --port 8000 --reload   # start dev server
+pytest tests/ -v                             # run all tests
+pytest tests/test_orders.py -v              # run single test file
+pytest tests/test_orders.py::test_name -v  # run single test
+```
+
+### Frontend (Vue 3 + Vite)
+```bash
+cd frontend
+npm run dev      # start dev server (port 5173)
+npm run build    # production build
+```
+
+### Docker (preferred for full stack)
+```bash
+make dev         # start all services (docker-compose.dev.yml)
+make test        # run backend tests in container
+make migrate     # run alembic migrations
+make seed        # seed demo data
+```
+
+## Architecture
+
+### Sync Model (critical to understand)
+- **Frontend writes locally first**, then queues changes in `_sync_queue` (SQLite table)
+- `SyncEngine` (`frontend/src/db/sync.js`) handles three operations:
+  - `fullSync()` — downloads all tenant data from `/api/sync/full` on login
+  - `incrementalSync()` — downloads changes since `last_sync_at`
+  - `pushQueue()` — uploads queued local changes to `/api/sync/push`
+- The backend sync service (`backend/app/sync/service.py`) defines `SYNCABLE_TABLES` — only these tables are synced
+- IDs are `crypto.randomUUID()` generated client-side; backend uses `INSERT OR REPLACE`
+
+### Frontend (`frontend/src/`)
+- **`db/database.js`** — singleton wa-sqlite instance. Uses `:memory:` only (no IndexedDB persistence). `execSQL(sql, params)` is the only query interface. Parameterized queries **must** use `sqlite3.statements()` async generator — `exec()` does not support `?` params. Do NOT use `prepare_v2` (doesn't exist in this library).
+- **`db/schema.js`** — full SQLite schema as a string constant, applied on init
+- **`db/sync.js`** — `SyncEngine` class, exported as singleton `syncEngine`
+- **`stores/`** — Pinia stores (`auth.js`, `orders.js`, `vehicles.js`) wrapping `execSQL` calls
+- **`views/`** — one file per route; data loaded via `execSQL` directly or through stores
+- **Reactivity** — `notifyTableChanged(table)` / `onTableChange(table, cb)` in `database.js` provide a pub/sub for cross-component updates. Call `notifyTableChanged` after any write.
+
+### Backend (`backend/app/`)
+- **Multi-tenant**: every model has `tenant_id`. All queries filter by `tenant_id` from the JWT.
+- **Auth**: JWT in `Authorization: Bearer` header. `get_tenant_id` dep extracts tenant from token.
+- **`deps.py`** — `get_current_user` and `get_tenant_id` FastAPI dependencies used across all routers
+- **`sync/`** — The most complex module. `apply_push` does `INSERT OR REPLACE` for all ops.
+- **`pdf/`** — WeasyPrint + Jinja2 HTML templates to generate PDF deviz/factura
+- **`client_portal/`** — Public routes (no auth) for client-facing deviz view via `token_client`
+- **DB**: SQLite via SQLAlchemy async (`aiosqlite`). Alembic for migrations (files in `alembic/versions/`).
+
+### Key Data Flow: Order Lifecycle
+`DRAFT` → `VALIDAT` → `FACTURAT`
+- Order lines (manopera/material) added only in DRAFT
+- PDF deviz available after VALIDAT
+- Invoice created locally in `handleFactureaza()` then queued for sync
+
+## Critical wa-sqlite Notes
+- Import: `wa-sqlite.mjs` (sync WASM build), NOT `wa-sqlite-async.mjs`
+- All API methods (`open_v2`, `exec`, `step`, `finalize`) return Promises — always `await`
+- For parameterized queries: `for await (const stmt of sqlite3.statements(db, sql))` then `sqlite3.bind_collection(stmt, params)`
+- `vite.config.js` excludes `@journeyapps/wa-sqlite` from `optimizeDeps`
+- COOP/COEP headers (`Cross-Origin-Opener-Policy: same-origin` + `Cross-Origin-Embedder-Policy: require-corp`) are required for SharedArrayBuffer used by wa-sqlite — set in vite dev server and nginx
+
+## WSL2 Note
+Running on WSL2 with code on Windows NTFS (`/mnt/e/`): Vite is configured with `server.watch.usePolling: true, interval: 1000` to work around inotify not firing on NTFS mounts.
+
+## Testing
+- Backend tests use an in-memory SQLite DB (overrides `get_db` via `app.dependency_overrides`)
+- `asyncio_mode = auto` set in `pytest.ini` — no need to mark tests with `@pytest.mark.asyncio`
+- `auth_headers` fixture registers a user and returns `Authorization` header for authenticated tests
+- Demo credentials (after `make seed`): `demo@roaauto.ro` / `demo123`