"""FastAPI application entrypoint.

Mounts:
  - REST API under /api
  - Socket.io under /socket.io (path) -> frontend connects to ws://host/socket.io
  - /health liveness probe
"""

from contextlib import asynccontextmanager

import socketio
from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse

from app.api import api_router
from app.core.config import get_settings
from app.core.database import init_db
from app.core.exceptions import AppError
from app.core.logging import get_logger, setup_logging
from app.websocket import sio

settings = get_settings()
logger = get_logger(__name__)


@asynccontextmanager
async def lifespan(app: FastAPI):  # type: ignore[no-untyped-def]
    setup_logging()
    logger.info("app.starting", env=settings.app_env)

    await init_db()
    await _seed_default_admin()

    # Attach Redis manager for Socket.io pub/sub (optional in dev)
    try:
        from socketio import AsyncRedisManager

        sio.manager = AsyncRedisManager(settings.redis_url)
        logger.info("ws.redis_manager_attached", url=settings.redis_url)
    except Exception as exc:  # noqa: BLE001 - Redis optional for scaffold
        logger.warning("ws.redis_unavailable", error=str(exc))

    yield

    logger.info("app.stopping")


async def _seed_default_admin() -> None:
    """Create the initial admin user if no users exist (dev bootstrap).

    Password comes from ADMIN_INITIAL_PASSWORD env, default 'admin' (dev only).
    """
    import os

    from sqlalchemy import func, select

    from app.core.database import async_session_factory
    from app.core.security import hash_password
    from app.models.user import User

    async with async_session_factory() as db:
        count = await db.scalar(select(func.count(User.id)))
        if count and count > 0:
            return
        password = os.environ.get("ADMIN_INITIAL_PASSWORD", "admin")
        db.add(
            User(
                username="admin",
                email=None,
                full_name="Administrator",
                password_hash=hash_password(password),
                is_admin=True,
            )
        )
        await db.commit()
        logger.info("app.default_admin_created", username="admin")


fastapi_app = FastAPI(
    title=settings.app_name,
    version="0.1.0",
    lifespan=lifespan,
)

fastapi_app.add_middleware(
    CORSMiddleware,
    allow_origins=settings.cors_origin_list,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


@fastapi_app.exception_handler(AppError)
async def app_error_handler(request: Request, exc: AppError) -> JSONResponse:  # noqa: ARG001
    return JSONResponse(status_code=exc.status_code, content={"detail": exc.detail})


@fastapi_app.get("/health")
async def health() -> dict:
    return {"status": "ok", "env": settings.app_env, "version": "0.1.0"}


fastapi_app.include_router(api_router)

# Combined ASGI app: FastAPI + Socket.io
app = socketio.ASGIApp(sio, other_asgi_app=fastapi_app, socketio_path="socket.io")