import bcrypt
import shutil
from dataclasses import dataclass
import sqlite3


@dataclass
class User:
    user_id: int
    email: str
    handle: str
    password: str
    display_name: str

    def __init__(
            self,
            user_id: int,
            email: str,
            handle: str,
            password: str = "",
            display_name: str = "",
    ) -> None:
        self.user_id: int = user_id
        self.handle = handle
        self.password = password
        self.display_name = display_name if display_name else handle
        self.email = email


class UserHandler:
    connection: sqlite3.Connection = sqlite3.connect("../data/database.db", check_same_thread=False)
    cursor: sqlite3.Cursor = connection.cursor()

    @classmethod
    def create_user(
        cls,
        user: User
    ) -> None:
        salt = bcrypt.gensalt()
        encrypted_password = bcrypt.hashpw(user.password.encode("utf-8"), salt)
        cls.cursor.execute(
                f"""
                INSERT INTO users(handle, display_name, email, password)
                values(?, ?, ?, ?)
                """,
                (user.handle, user.display_name, user.email, encrypted_password)
        )
        cls.connection.commit()
        shutil.copy(
                "../assets/profile_pictures/default_profile_picture.jpg",
                f"../assets/profile_pictures/{user.handle}"
        )

    @classmethod
    def get_user_by_id(cls, user_id: int) -> User:
        users = cls.cursor.execute(
                f"""
                SELECT handle, display_name
                FROM users WHERE user_id = ?;
                """,
                (user_id, )
        ).fetchall()
        if not users:
            raise KeyError(f"{user_id} does not exist!")
        user = users[0]
        return User(
                user_id=user_id,
                handle=user[0],
                display_name=user[1],
                email="",
                password=""
        )

    @classmethod
    def get_user_by_handle(cls, handle: str) -> User:
        users = cls.cursor.execute(
                f"""
                SELECT user_id, handle, display_name
                FROM users WHERE handle = ?;
                """,
                (handle, )
        ).fetchall()
        if not users:
            raise KeyError(f"{handle} does not exist!")
        users = users[0]
        return User(
                user_id=users[0],
                handle=users[1],
                display_name=users[2],
                email="",
                password=""
        )

    @classmethod
    def get_user_by_email(cls, email: str) -> User:
        users = cls.cursor.execute(
                f"""
                SELECT user_id, handle, display_name
                FROM users WHERE email = ?;
                """,
                (email, )
        ).fetchall()
        if not users:
            raise KeyError(f"{email} does not exist!")
        users = users[0]
        return User(
                user_id=users[0],
                handle=users[1],
                display_name=users[2],
                email=email,
                password="",
        )

    #@classmethod
    #def verify_password_by_handle(cls, handle: str, password: str) -> bool:
    #    users = cls.cursor.execute(
    #            f"""
    #            SELECT password
    #            FROM users WHERE handle = ?;
    #            """,
    #            (handle, )
    #    ).fetchall()
    #    if not users:
    #        raise KeyError(f"{handle} does not exist!")
    #    real_password = users[0][0]
    #    return bcrypt.checkpw(password.encode("utf-8"), real_password)

    @classmethod
    def verify_password_by_email(cls, email: str, password: str) -> bool:
        users = cls.cursor.execute(
                f"""
                SELECT password
                FROM users WHERE email = ?;
                """,
                (email, )
        ).fetchall()
        if not users:
            raise KeyError(f"{email} does not exist!")
        return bcrypt.checkpw(password.encode("utf-8"), users[0][0])

    @classmethod
    def change_display_name(cls, user_id: int, display_name: str):
        cls.cursor.execute(
                f"""
                UPDATE users
                SET display_name = ?
                WHERE user_id = ?;
                """,
                (display_name, user_id)
        ).fetchall()

    @classmethod
    def get_display_name(cls, user_id: int) -> str:
        return cls.get_user_by_id(user_id).display_name