"""Calendar API router.

BE-CAL-004: MinimumWorkload CRUD endpoints.
Future tasks (BE-CAL-API-*) will add slot/plan endpoints here.
"""

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

from app.api.deps import get_current_user
from app.core.config import get_db
from app.models.models import User
from app.schemas.calendar import (
    MinimumWorkloadConfig,
    MinimumWorkloadResponse,
    MinimumWorkloadUpdate,
)
from app.services.minimum_workload import (
    get_workload_config,
    replace_workload_config,
    upsert_workload_config,
)

router = APIRouter(prefix="/calendar", tags=["Calendar"])


# ---------------------------------------------------------------------------
# MinimumWorkload
# ---------------------------------------------------------------------------

@router.get(
    "/workload-config",
    response_model=MinimumWorkloadResponse,
    summary="Get current user's minimum workload configuration",
)
def get_my_workload_config(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """Return the workload thresholds for the authenticated user.

    If no configuration has been saved yet, returns default (all-zero)
    thresholds.
    """
    cfg = get_workload_config(db, current_user.id)
    return MinimumWorkloadResponse(user_id=current_user.id, config=cfg)


@router.put(
    "/workload-config",
    response_model=MinimumWorkloadResponse,
    summary="Replace the current user's minimum workload configuration",
)
def put_my_workload_config(
    payload: MinimumWorkloadConfig,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """Full replacement of the workload configuration."""
    row = replace_workload_config(db, current_user.id, payload)
    db.commit()
    db.refresh(row)
    return MinimumWorkloadResponse(user_id=current_user.id, config=row.config)


@router.patch(
    "/workload-config",
    response_model=MinimumWorkloadResponse,
    summary="Partially update the current user's minimum workload configuration",
)
def patch_my_workload_config(
    payload: MinimumWorkloadUpdate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """Partial update — only the provided periods are overwritten."""
    row = upsert_workload_config(db, current_user.id, payload)
    db.commit()
    db.refresh(row)
    return MinimumWorkloadResponse(user_id=current_user.id, config=row.config)


# ---------------------------------------------------------------------------
# Admin: manage another user's workload config
# ---------------------------------------------------------------------------

def _require_admin(current_user: User = Depends(get_current_user)):
    if not current_user.is_admin:
        raise HTTPException(status_code=403, detail="Admin required")
    return current_user


@router.get(
    "/workload-config/{user_id}",
    response_model=MinimumWorkloadResponse,
    summary="[Admin] Get a specific user's minimum workload configuration",
)
def get_user_workload_config(
    user_id: int,
    db: Session = Depends(get_db),
    _admin: User = Depends(_require_admin),
):
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    cfg = get_workload_config(db, user_id)
    return MinimumWorkloadResponse(user_id=user_id, config=cfg)


@router.put(
    "/workload-config/{user_id}",
    response_model=MinimumWorkloadResponse,
    summary="[Admin] Replace a specific user's minimum workload configuration",
)
def put_user_workload_config(
    user_id: int,
    payload: MinimumWorkloadConfig,
    db: Session = Depends(get_db),
    _admin: User = Depends(_require_admin),
):
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    row = replace_workload_config(db, user_id, payload)
    db.commit()
    db.refresh(row)
    return MinimumWorkloadResponse(user_id=user_id, config=row.config)


@router.patch(
    "/workload-config/{user_id}",
    response_model=MinimumWorkloadResponse,
    summary="[Admin] Partially update a specific user's minimum workload configuration",
)
def patch_user_workload_config(
    user_id: int,
    payload: MinimumWorkloadUpdate,
    db: Session = Depends(get_db),
    _admin: User = Depends(_require_admin),
):
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    row = upsert_workload_config(db, user_id, payload)
    db.commit()
    db.refresh(row)
    return MinimumWorkloadResponse(user_id=user_id, config=row.config)