"""Health endpoint — also the smoke test for database connectivity."""

from fastapi import APIRouter, Depends
from sqlalchemy import text
from sqlalchemy.orm import Session

from app.core.config import get_settings
from app.db.session import get_db
from app.schemas.health import HealthResponse

router = APIRouter(tags=["health"])


@router.get("/health", response_model=HealthResponse, summary="Liveness and database probe")
def health(db: Session = Depends(get_db)) -> HealthResponse:
    """Report process liveness and whether TiDB answered a trivial query.

    A database failure is reported in the body instead of raising, so that the
    endpoint stays useful for diagnosing an unreachable database.
    """
    settings = get_settings()
    try:
        db.execute(text("SELECT 1"))
        database = "ok"
    except Exception:  # noqa: BLE001 - the failure mode is the payload
        database = "unavailable"

    return HealthResponse(
        status="ok" if database == "ok" else "degraded",
        app=settings.app_name,
        database=database,
        database_target=settings.safe_database_url,
    )