from sqlalchemy.orm import Session

from app.core.security import hash_password, verify_password
from app.models.user import User
from app.schemas.auth import RegisterRequest


class EmailAlreadyRegisteredError(Exception):
    pass


def get_user_by_email(db: Session, email: str) -> User | None:
    return db.query(User).filter(User.email == email).first()


def get_user_by_id(db: Session, user_id: int) -> User | None:
    return db.query(User).filter(User.id == user_id).first()


def register_user(db: Session, body: RegisterRequest) -> User:
    if get_user_by_email(db, body.email):
        raise EmailAlreadyRegisteredError()
    user = User(
        email=body.email,
        hashed_password=hash_password(body.password),
        full_name=body.full_name,
        is_active=True,
    )
    db.add(user)
    db.commit()
    db.refresh(user)
    return user


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