"""FastAPI api."""

# pyright: reportUnusedFunction=false
import logging
from contextlib import asynccontextmanager

from fastapi import (
    FastAPI,
    Request,
    status,
)
from fastapi.encoders import jsonable_encoder
from fastapi.exceptions import RequestValidationError
from fastapi.responses import JSONResponse


from .models import init_db_async
from .backend_api import get_backend_api
from .db import get_async_engine

from .settings import BackendSettings

LOG = logging.getLogger(__name__)


def init_backend_app(settings: BackendSettings) -> FastAPI:
    """Initialize backend app."""

    @asynccontextmanager
    async def lifespan(_app: FastAPI):
        """Create database before starting the server."""
        LOG.debug("Running lifespan")
        engine = get_async_engine(settings.async_db_url)
        await init_db_async(engine)
        yield

    app = FastAPI(lifespan=lifespan)
    app.include_router(get_backend_api(settings))

    @app.exception_handler(RequestValidationError)
    async def validation_exception_handler(
        request: Request, exc: RequestValidationError
    ):
        return JSONResponse(
            status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
            content=jsonable_encoder({"detail": exc.errors(), "body": exc.body}),
        )

    @app.get("/health")
    async def get_health() -> JSONResponse:
        """Provide simple health check."""
        return JSONResponse(
            status_code=status.HTTP_200_OK, content=jsonable_encoder({"status": "LIVE"})
        )

    return app


def create_backend_app(settings: BackendSettings) -> FastAPI:
    """Create the backend app."""

    return init_backend_app(settings)