import logging
from datetime import datetime

from sqlalchemy.orm import Session

from .import models, schemas

log = logging.getLogger()


def hash_password(password: str) -> str:
    # TODO actually hash the password!
    return password


def _fill_missing_user_fields(db_user: models.User) -> schemas.User:
    full_user = schemas.User.from_orm(db_user)
    if db_user.patient:
        full_user.gender = db_user.patient.gender
        full_user.date_of_birth = db_user.patient.date_of_birth
        full_user.is_patient = True
        full_user.is_admin = False
    else:
        full_user.is_patient = False
        full_user.is_admin = True

    return full_user


def create_user(db: Session, user: schemas.UserCreate):
    """Creates a new user as either a patient or an administrator."""

    db_user = models.User(
        email=user.email,
        first_name=user.first_name,
        last_name=user.last_name,
        password=hash_password(user.password),
    )

    # Add user to database
    if user.is_patient:
        db_patient = models.Patient(
            user=db_user,
            gender=user.gender,
            date_of_birth=user.date_of_birth,
        )
        db.add(db_patient)
    else:
        db_administrator = models.Administrator(
            user=db_user,
        )
        db.add(db_administrator)

    db.commit()

    # Construct the updated user to return
    db.refresh(db_user)
    return _fill_missing_user_fields(db_user)


def read_user(db: Session, id: int):
    db_user = db.query(models.User).filter(models.User.id == id).first()
    if not db_user:
        return None

    return _fill_missing_user_fields(db_user)


def read_user_by_email(db: Session, email: str):
    db_user = db.query(models.User).filter(models.User.email == email).first()
    if not db_user:
        return None
    
    return _fill_missing_user_fields(db_user)


def read_users(db: Session, skip: int = 0, limit: int = 100):
    db_users = db.query(models.User).offset(skip).limit(limit).all()
    
    full_users = []
    for db_user in db_users:
        full_users.append(_fill_missing_user_fields(db_user))
    return full_users


def update_user(db: Session, user: schemas.UserUpdate, id: int):
    db_user = db.query(models.User).filter(models.User.id == id).first()
    current_user = _fill_missing_user_fields(db_user)

    for key in ['gender', 'date_of_birth']:
        value = getattr(user, key)
        if value is not None:
            setattr(db_user.patient, key, value)
    for key in ['email', 'first_name', 'last_name']:
        value = getattr(user, key)
        if value is not None:
            setattr(db_user, key, value)
    if user.password is not None:
        db_user.password = hash_password(user.password)

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


def delete_user(db: Session, id: int):
    db_user = db.query(models.User).filter(models.User.id == id).first()
    user_copy = _fill_missing_user_fields(db_user)

    db.delete(db_user)
    db.commit()

    user_copy.updated = datetime.now(user_copy.updated.tzinfo)
    return user_copy