from base64 import b64decode, b64encode
from dataclasses import dataclass
import json
from random import randbytes
from typing import Optional, Any, Self

from bson.objectid import ObjectId
import scrypt
import jwt

from roc_fnb.util.base64 import base64_encode, base64_decode

with open('private-key.pem') as file:
    PRIVATE_KEY = file.read()

with open('public-key.pem') as file:
    PUBLIC_KEY = file.read()

@dataclass
class JwtUser:
    _id: ObjectId
    email: str
    name: str
    moderator: bool
    admin: bool

    @classmethod
    def from_json(cls, data: dict) -> Self:
        _id = ObjectId(base64_decode(data.pop('_id')))
        return cls(_id=_id, **data)


@dataclass
class User:
    _id: Optional[ObjectId]
    email: str
    name: str
    password_hash: bytes
    salt: bytes
    moderator: bool
    admin: bool

    @classmethod
    def create(cls, email: str, name: str, password: str|bytes, moderator: bool = False, admin: bool = False):
        """Alternate constructor which hashes a given password"""
        salt = randbytes(32)
        password_hash = scrypt.hash(password, salt)
        return cls(_id=None,
                   email=email,
                   name=name,
                   password_hash=password_hash,
                   salt=salt,
                   moderator=moderator,
                   admin=admin)

    @property
    def document(self):
        doc = {
            "email": self.email,
            "name": self.name,
            "password_hash": self.password_hash,
            "salt": self.salt,
            "moderator": self.moderator,
            "admin": self.admin,
        }
        if self._id is not None:
            doc['_id'] = self._id
        return doc

    @property
    def public_fields(self):
        """
        Session data is visible to client scripts.
        
        This is a feature, not a bug; client scripts may need to gather login info.
        """
        return {
            '_id': base64_encode(self._id.binary),
            "email": self.email,
            "name": self.name,
            "moderator": self.moderator,
            "admin": self.admin,
        }

    def check_password(self, password: str) -> bool:
        return self.password_hash == scrypt.hash(password, self.salt)