"""
User management service.
"""

from sqlalchemy import func, select
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.security import hash_password
from app.models.user import User
from app.schemas.user import UserCreate, UserUpdate


async def create_user(
    db: AsyncSession,
    data: UserCreate,
) -> User:
    """
    Create a new user.

    Args:
        db: Database session
        data: User creation data

    Returns:
        Created user
    """
    # Hash password
    hashed_password = hash_password(data.password)

    user = User(
        email=data.email,
        hashed_password=hashed_password,
        full_name=data.full_name,
        phone=data.phone,
        role=data.role,
        organization_id=data.organization_id,
        status="active",  # Superadmin creates active users
        email_verified=True,  # Auto-verify for superadmin-created users
    )

    db.add(user)
    await db.commit()
    await db.refresh(user)

    return user


async def get_user(db: AsyncSession, user_id: int) -> User | None:
    """
    Get user by ID.

    Args:
        db: Database session
        user_id: User ID

    Returns:
        User or None
    """
    result = await db.execute(select(User).where(User.id == user_id))
    return result.scalar_one_or_none()


async def get_user_by_email(db: AsyncSession, email: str) -> User | None:
    """
    Get user by email.

    Args:
        db: Database session
        email: User email

    Returns:
        User or None
    """
    result = await db.execute(select(User).where(User.email == email))
    return result.scalar_one_or_none()


async def list_users(
    db: AsyncSession,
    skip: int = 0,
    limit: int = 100,
    organization_id: int | None = None,
    role: str | None = None,
    status: str | None = None,
) -> tuple[list[User], int]:
    """
    List users with pagination and filters.

    Args:
        db: Database session
        skip: Number of records to skip
        limit: Maximum number of records to return
        organization_id: Filter by organization (optional)
        role: Filter by role (optional)
        status: Filter by status (optional)

    Returns:
        Tuple of (users list, total count)
    """
    # Build query
    query = select(User)

    if organization_id is not None:
        query = query.where(User.organization_id == organization_id)

    if role:
        query = query.where(User.role == role)

    if status:
        query = query.where(User.status == status)

    # Get total count
    count_query = select(func.count()).select_from(User)

    if organization_id is not None:
        count_query = count_query.where(User.organization_id == organization_id)

    if role:
        count_query = count_query.where(User.role == role)

    if status:
        count_query = count_query.where(User.status == status)

    total_result = await db.execute(count_query)
    total = total_result.scalar_one()

    # Get paginated results
    query = query.offset(skip).limit(limit).order_by(User.created_at.desc())
    result = await db.execute(query)
    users = list(result.scalars().all())

    return users, total


async def update_user(
    db: AsyncSession,
    user_id: int,
    data: UserUpdate,
) -> User | None:
    """
    Update user.

    Args:
        db: Database session
        user_id: User ID
        data: Update data

    Returns:
        Updated user or None if not found
    """
    result = await db.execute(select(User).where(User.id == user_id))
    user = result.scalar_one_or_none()

    if not user:
        return None

    # Update fields
    update_data = data.model_dump(exclude_unset=True)
    for field, value in update_data.items():
        setattr(user, field, value)

    await db.commit()
    await db.refresh(user)

    return user


async def delete_user(
    db: AsyncSession,
    user_id: int,
) -> bool:
    """
    Delete user.

    Args:
        db: Database session
        user_id: User ID

    Returns:
        True if deleted, False if not found
    """
    result = await db.execute(select(User).where(User.id == user_id))
    user = result.scalar_one_or_none()

    if not user:
        return False

    await db.delete(user)
    await db.commit()

    return True


async def change_user_password(
    db: AsyncSession,
    user_id: int,
    new_password: str,
) -> User | None:
    """
    Change user password.

    Args:
        db: Database session
        user_id: User ID
        new_password: New password (plain text)

    Returns:
        Updated user or None if not found
    """
    result = await db.execute(select(User).where(User.id == user_id))
    user = result.scalar_one_or_none()

    if not user:
        return None

    user.hashed_password = hash_password(new_password)

    await db.commit()
    await db.refresh(user)

    return user