"""Users management router"""

from fastapi import APIRouter, Depends, HTTPException, status, Query
from typing import List, Optional
from bson import ObjectId
from app.models.user import User, UserUpdate, UserRole
from app.routers.auth import get_current_user
from app.utils.database import get_database
from app.utils.security import hash_password
from datetime import datetime

router = APIRouter(prefix="/users", tags=["Users"])


def require_admin(current_user: User = Depends(get_current_user)) -> User:
    """Require admin role"""
    if current_user.role not in [UserRole.SYSTEM_ADMIN, UserRole.GROUP_ADMIN]:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions"
        )
    return current_user


@router.get("/", response_model=List[User])
async def get_users(
    skip: int = Query(0, ge=0),
    limit: int = Query(10, ge=1, le=100),
    current_user: User = Depends(require_admin)
):
    """Get all users (admin only)"""
    db = get_database()
    
    users = await db.users.find().skip(skip).limit(limit).to_list(limit)
    return [User(**user) for user in users]


@router.get("/{user_id}", response_model=User)
async def get_user(user_id: str, current_user: User = Depends(get_current_user)):
    """Get user by ID"""
    # Users can only view their own profile unless they're admin
    if str(current_user.id) != user_id and current_user.role not in [UserRole.SYSTEM_ADMIN, UserRole.GROUP_ADMIN]:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions"
        )
    
    db = get_database()
    
    try:
        user = await db.users.find_one({"_id": ObjectId(user_id)})
        if not user:
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="User not found"
            )
        return User(**user)
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Invalid user ID"
        )


@router.put("/{user_id}", response_model=User)
async def update_user(
    user_id: str,
    user_update: UserUpdate,
    current_user: User = Depends(get_current_user)
):
    """Update user"""
    # Users can only update their own profile unless they're admin
    if str(current_user.id) != user_id and current_user.role not in [UserRole.SYSTEM_ADMIN, UserRole.GROUP_ADMIN]:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Not enough permissions"
        )
    
    # Only system admin can change roles
    if user_update.role and current_user.role != UserRole.SYSTEM_ADMIN:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Only system admin can change user roles"
        )
    
    db = get_database()
    
    try:
        # Prepare update data
        update_data = user_update.model_dump(exclude_unset=True)
        
        # Hash password if provided
        if "password" in update_data:
            update_data["hashed_password"] = hash_password(update_data.pop("password"))
        
        # Update timestamp
        update_data["updated_at"] = datetime.utcnow()
        
        # Update user
        result = await db.users.update_one(
            {"_id": ObjectId(user_id)},
            {"$set": update_data}
        )
        
        if result.modified_count == 0:
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="User not found"
            )
        
        # Return updated user
        user = await db.users.find_one({"_id": ObjectId(user_id)})
        return User(**user)
        
    except Exception as e:
        if isinstance(e, HTTPException):
            raise
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e)
        )


@router.delete("/{user_id}")
async def delete_user(
    user_id: str,
    current_user: User = Depends(require_admin)
):
    """Delete user (admin only)"""
    # Prevent self-deletion
    if str(current_user.id) == user_id:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Cannot delete your own account"
        )
    
    db = get_database()
    
    try:
        result = await db.users.delete_one({"_id": ObjectId(user_id)})
        
        if result.deleted_count == 0:
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="User not found"
            )
        
        return {"message": "User deleted successfully"}
        
    except Exception as e:
        if isinstance(e, HTTPException):
            raise
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Invalid user ID"
        )