"""Stations router - CRUD + recipe assignments."""
from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession

from src.backend.database import get_db
from src.backend.api.middleware.api_key import get_current_user, require_admin_user
from src.backend.models.orm.user import User
from src.backend.models.api.station import (
    StationCreate,
    StationUpdate,
    StationResponse,
    StationRecipeAssignmentCreate,
    StationRecipeAssignmentResponse,
    RecipeSummary,
)
from src.backend.services import station_service

router = APIRouter(prefix="/api/stations", tags=["stations"])


@router.get("", response_model=list[StationResponse])
async def list_stations(
    active_only: bool = False,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """List all stations (admin only)."""
    stations = await station_service.list_stations(db, active_only=active_only)
    return [StationResponse.model_validate(s) for s in stations]


@router.post("", response_model=StationResponse, status_code=status.HTTP_201_CREATED)
async def create_new_station(
    data: StationCreate,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Create a station (admin only)."""
    station = await station_service.create_station(db, data, admin)
    return StationResponse.model_validate(station)


# NOTE: this literal-prefix route must stay above the /{station_id} routes.
# The int-typed station_id param already guards against "by-code" being
# matched as a station id, but keeping the explicit order avoids surprises
# during refactors (e.g. if someone regroups handlers by HTTP method).
@router.get("/by-code/{code}/recipes", response_model=list[RecipeSummary])
async def list_recipes_by_station_code(
    code: str,
    user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Operator view: active recipes assigned to the station with this code.

    Used by the Flask client at startup / on select_recipe page.
    Any authenticated user can call this; filtering is by station code from
    the client's STATION_CODE environment variable.
    """
    station = await station_service.get_station_by_code(db, code)
    if station is None or not station.active:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Station not found",
        )
    recipes = await station_service.list_station_recipes(db, station.id)
    return [RecipeSummary.model_validate(r) for r in recipes]


@router.get("/{station_id}", response_model=StationResponse)
async def get_single_station(
    station_id: int,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Get a station by id (admin only)."""
    station = await station_service.get_station(db, station_id)
    return StationResponse.model_validate(station)


@router.put("/{station_id}", response_model=StationResponse)
async def update_existing_station(
    station_id: int,
    data: StationUpdate,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Update a station (admin only)."""
    station = await station_service.update_station(db, station_id, data)
    return StationResponse.model_validate(station)


@router.delete("/{station_id}", status_code=status.HTTP_204_NO_CONTENT)
async def remove_station(
    station_id: int,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Delete a station (admin only). Cascades to assignments."""
    await station_service.delete_station(db, station_id)


@router.get("/{station_id}/recipes", response_model=list[RecipeSummary])
async def list_assigned_recipes(
    station_id: int,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Admin view: recipes assigned to this station (active only)."""
    recipes = await station_service.list_station_recipes(db, station_id)
    return [RecipeSummary.model_validate(r) for r in recipes]


@router.post(
    "/{station_id}/recipes",
    response_model=StationRecipeAssignmentResponse,
    status_code=status.HTTP_201_CREATED,
)
async def assign_recipe_to_station(
    station_id: int,
    data: StationRecipeAssignmentCreate,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Assign a recipe to a station (admin only)."""
    assignment = await station_service.assign_recipe(
        db, station_id, data.recipe_id, admin,
    )
    return StationRecipeAssignmentResponse.model_validate(assignment)


@router.delete(
    "/{station_id}/recipes/{recipe_id}",
    status_code=status.HTTP_204_NO_CONTENT,
)
async def unassign_recipe_from_station(
    station_id: int,
    recipe_id: int,
    admin: User = Depends(require_admin_user),
    db: AsyncSession = Depends(get_db),
):
    """Remove a recipe assignment (admin only)."""
    await station_service.unassign_recipe(db, station_id, recipe_id)
