# wizard_server

FastAPI game server. It manages sessions, lobbies and games, and talks to the AI service.

- `game_logic/` — the standalone rules engine (`pip install ./game_logic`, see its README).
- `app/main.py` — routes: `GET /health`, `WS /ws` (browsers), `WS /internal/ai` (AI service,
  refused when the request came through the reverse proxy)
- `app/protocol.py` — client message schema
- `app/service.py` — dispatches client messages, reconnects sessions, cleanup
- `app/lobby.py` — lobbies, seats, host actions, running games and AI turns
- `app/ai_bridge.py` — request/response protocol with the AI service, random-move fallback,
  in-flight cap and circuit breaker
- `app/sessions.py` — sessions (token based, survive reloads) and ordered websocket sending
- `app/limits.py` — token bucket, per-IP rate limiter, connection limiter (abuse protection)
- `app/load.py` — load monitor (event loop lag, CPU, cgroup throttling) with hysteresis; the
  service refuses new lobbies/games while overloaded or at `MAX_ACTIVE_GAMES`

Configuration (environment, all in `app/config.py`): `AI_SHARED_SECRET`, `AI_DECISION_TIMEOUT` (5s),
`AI_MOVE_DELAY` (0.8s), `TRICK_PAUSE` (1.8s), `SESSION_TTL` (1800s), `MAX_LOBBIES` (1000),
`ALLOWED_ORIGINS`, `LOG_LEVEL`, and the limits: `MAX_CONNECTIONS` (500), `MAX_CONNECTIONS_PER_IP` (10),
`MESSAGE_RATE`/`MESSAGE_BURST` (10/30), `LOBBY_CREATE_RATE` (10/min), `MAX_ACTIVE_GAMES` (50),
`LOAD_*` thresholds, `AI_MAX_INFLIGHT` (64), `AI_BREAKER_FAILURES`/`AI_BREAKER_COOLDOWN` (5/30s).
See `../docs/04-server.md` and `../docs/09-limits-and-performance.md`.

```bash
pip install -r requirements-dev.txt
uvicorn app.main:app --reload
pytest
```