from jose import jwt, JOSEError
from pydantic import BaseModel
from datetime import timedelta, datetime
from typing import ClassVar, Literal
import logging
from fooder.settings import settings
from fooder.exc import Unauthorized


class Token(BaseModel):
    exp: datetime
    sub: int

    secret_key: ClassVar[str]
    expire_delta: ClassVar[timedelta]

    @classmethod
    def calculate_exp(cls, now: datetime) -> datetime:
        return now + cls.expire_delta

    @classmethod
    def decode(cls, jwt_token: str | bytes) -> "Token":
        try:
            data = jwt.decode(
                jwt_token, cls.secret_key, algorithms=[settings.ALGORITHM]
            )
        except JOSEError as e:
            logging.error(e)
            raise Unauthorized()
        return cls(**data)

    def encode(self) -> str:
        data = self.model_dump()
        data["sub"] = str(data["sub"])
        return jwt.encode(data, self.secret_key, settings.ALGORITHM)


class AccessToken(Token):
    secret_key = settings.SECRET_KEY
    expire_delta = timedelta(minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES)


class RefreshToken(Token):
    secret_key = settings.REFRESH_SECRET_KEY
    expire_delta = timedelta(days=settings.REFRESH_TOKEN_EXPIRE_DAYS)


def generate_token_pair(entity_id: int, now: datetime) -> tuple[AccessToken, RefreshToken]:
    return (
        AccessToken(exp=AccessToken.calculate_exp(now), sub=entity_id),
        RefreshToken(exp=RefreshToken.calculate_exp(now), sub=entity_id),
    )