"""User management endpoints (admin only)."""

from typing import Any, List
from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from app import crud, schemas
from app.dependencies import get_db, get_current_user, get_current_active_superuser
from app.models.user import User


router = APIRouter()


@router.get("", response_model=List[schemas.User])
def list_users(
    *,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_active_superuser),
    skip: int = 0,
    limit: int = 100
) -> Any:
    """
    List all users (admin only).

    Requires superuser privileges.
    """
    users = crud.user.get_multi(db, skip=skip, limit=limit)
    return users


@router.get("/{user_id}", response_model=schemas.User)
def get_user(
    *,
    db: Session = Depends(get_db),
    user_id: str,
    current_user: User = Depends(get_current_user)
) -> Any:
    """
    Get user by ID.

    Users can view their own profile, admins can view any profile.
    """
    user = crud.user.get(db, id=user_id)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )

    # Check if user is viewing their own profile or is superuser
    if user.id != current_user.id and not current_user.is_superuser:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions"
        )

    return user


@router.put("/{user_id}", response_model=schemas.User)
def update_user(
    *,
    db: Session = Depends(get_db),
    user_id: str,
    user_in: schemas.UserUpdate,
    current_user: User = Depends(get_current_user)
) -> Any:
    """
    Update user.

    Users can update their own profile, admins can update any profile.
    Only admins can change is_superuser and is_active flags.
    """
    user = crud.user.get(db, id=user_id)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )

    # Check permissions
    if user.id != current_user.id and not current_user.is_superuser:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions"
        )

    # Only superusers can change is_superuser and is_active
    if not current_user.is_superuser:
        if (
            user_in.is_superuser is not None
            or user_in.is_active is not None
            or user_in.permissions is not None
        ):
            raise HTTPException(
                status_code=status.HTTP_403_FORBIDDEN,
                detail="Only admins can change user status or permissions"
            )

    user = crud.user.update(db, db_obj=user, obj_in=user_in)
    return user


@router.delete("/{user_id}", response_model=schemas.User)
def delete_user(
    *,
    db: Session = Depends(get_db),
    user_id: str,
    current_user: User = Depends(get_current_active_superuser)
) -> Any:
    """
    Delete user (admin only).

    Requires superuser privileges.
    Users cannot delete themselves.
    """
    if user_id == current_user.id:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Users cannot delete themselves"
        )

    user = crud.user.get(db, id=user_id)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )

    user = crud.user.remove(db, id=user_id)
    return user


@router.post("", response_model=schemas.User, status_code=status.HTTP_201_CREATED)
def create_user(
    *,
    db: Session = Depends(get_db),
    user_in: schemas.UserCreate,
    current_user: User = Depends(get_current_active_superuser)
) -> Any:
    """
    Create new user (admin only).

    Requires superuser privileges.
    """
    # Check if username already exists
    user = crud.user.get_by_username(db, username=user_in.username)
    if user:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Username already registered"
        )

    # Check if email already exists
    user = crud.user.get_by_email(db, email=user_in.email)
    if user:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Email already registered"
        )

    user = crud.user.create(db, obj_in=user_in)
    return user