from sqlalchemy.orm import Session
from app.models.user import User
from app.schemas.user import UserCreate, UserUpdate
from app.core.security import get_password_hash, verify_password
from typing import Optional


def get_user_by_email(db: Session, email: str) -> Optional[User]:
    return db.query(User).filter(User.email == email).first()


def get_user_by_id(db: Session, user_id: int) -> Optional[User]:
    return db.query(User).filter(User.id == user_id).first()


def create_user(db: Session, user: UserCreate) -> User:
    hashed_password = get_password_hash(user.password)
    db_user = User(
        email=user.email,
        hashed_password=hashed_password,
        full_name=user.full_name,
    )
    db.add(db_user)
    db.commit()
    db.refresh(db_user)
    return db_user


def authenticate_user(db: Session, email: str, password: str) -> Optional[User]:
    user = get_user_by_email(db, email)
    if not user:
        return None
    if not verify_password(password, user.hashed_password):
        return None
    return user


def update_user(db: Session, user_id: int, user_update: UserUpdate) -> Optional[User]:
    db_user = get_user_by_id(db, user_id)
    if not db_user:
        return None

    update_data = user_update.dict(exclude_unset=True)

    if "password" in update_data:
        update_data["hashed_password"] = get_password_hash(update_data.pop("password"))

    for field, value in update_data.items():
        setattr(db_user, field, value)

    db.commit()
    db.refresh(db_user)
    return db_user