from rest_framework_simplejwt.authentication import JWTAuthentication
from rest_framework_simplejwt.exceptions import InvalidToken


class StatelessUser:
    """
    Stateless user class for JWT authentication.
    Does not require database User model.
    """

    def __init__(self, username):
        self.username = username
        self.is_authenticated = True

    def __str__(self):
        return self.username


class StatelessJWTAuthentication(JWTAuthentication):
    """
    Custom JWT authentication that extracts user from token's 'name' claim.
    """

    def get_user(self, validated_token):
        name = validated_token.get("name")
        if not name:
            raise InvalidToken("Token does not contain 'name' claim.")
        return StatelessUser(username=name)