from typing import List

from django.conf import settings
from django.contrib.auth import get_user_model
from django.contrib.auth.password_validation import (
    get_password_validators,
    validate_password,
)
from rest_framework import serializers
from rest_framework.exceptions import ValidationError
from rest_framework_simplejwt.serializers import TokenObtainPairSerializer

User = get_user_model()


AUTH_PASSWORD_VALIDATORS = getattr(settings, "AUTH_PASSWORD_VALIDATORS")


class UserSerializer(serializers.ModelSerializer):
    permissions = serializers.SerializerMethodField()

    def get_permissions(self, obj: User) -> List[str]:
        group_permissions = obj.get_group_permissions()
        user_permissions = obj.get_user_permissions()

        return sorted(user_permissions.union(group_permissions))

    class Meta:
        model = User
        fields = (
            "username",
            "email",
            "first_name",
            "last_name",
            "is_staff",
            "is_superuser",
            "permissions",
        )
        read_only_fields = (
            "username",
            "code",
            "is_staff",
            "is_superuser",
            "permissions",
        )


class UpdatePasswordSerializer(serializers.ModelSerializer):
    old_password = serializers.CharField(write_only=True)
    new_password = serializers.CharField(write_only=True)
    new_password2 = serializers.CharField(write_only=True)

    def validate_old_password(self, password):
        user = self.context.get("request").user

        if not user.check_password(password):
            raise ValidationError("Wrong old password")

        return password

    def validate_new_password(self, password):
        old_password = self.context.get("request").data.get("old_password")

        if password == old_password:
            raise ValidationError("Password can't be the same as the old one")

        password2 = self.context.get("request").data.get("new_password2")
        if password != password2:
            raise ValidationError("Password mismatch")

        validate_password(
            password,
            password_validators=get_password_validators(AUTH_PASSWORD_VALIDATORS),
        )

        return password

    def save(self, *args, **kwargs):
        new_password = self.validated_data.get("new_password")
        self.instance.set_password(new_password)
        self.instance.save()

    class Meta:
        model = User
        fields = (
            "old_password",
            "new_password",
            "new_password2",
        )