from __future__ import annotations

import logging
from datetime import timedelta

from django.utils import timezone
from django.utils.crypto import get_random_string
from drf_spectacular.utils import (
    OpenApiResponse,
    extend_schema,
    inline_serializer,
)
from rest_framework import serializers
from rest_framework.response import Response

from api.v1.employees.serializers import (
    EmailSerializer,
    EmailVerifySerializer,
)
from api.v1.employees.views._helpers import Employee
from common.emails import send_templated_mail

from ..base import AnonymousAPIView

logger = logging.getLogger(__name__)


class ResendEmailAPIView(AnonymousAPIView):
    throttle_scope = "auth_email"

    @extend_schema(
        tags=["Auth"],
        summary="Повторно отправить код подтверждения email",
        request=EmailSerializer,
        responses={
            200: inline_serializer(
                "ResendEmailResponse",
                {"ok": serializers.BooleanField()},
            ),
            400: OpenApiResponse(description="Email уже подтвержден."),
            404: OpenApiResponse(description="Пользователь не найден."),
        },
    )
    def post(self, request):
        ser = EmailSerializer(data=request.data)
        ser.is_valid(raise_exception=True)
        email = ser.validated_data["email"]

        user = Employee.objects.filter(email__iexact=email).first()
        if not user:
            return Response({"ok": False, "error": "user_not_found"}, status=404)
        if user.email_verified:
            return Response({"ok": False, "error": "already_verified"}, status=400)

        user.email_activation_code = get_random_string(6, "0123456789")
        user.email_activation_sent_at = timezone.now()
        user.save(
            update_fields=[
                "email_activation_code",
                "email_activation_sent_at",
            ]
        )

        send_templated_mail(
            subject="Подтверждение регистрации",
            to=[user.email],
            template_base="emails/registration_verify_code",
            context={"code": user.email_activation_code, "user": user},
        )
        return Response({"ok": True}, status=200)


class VerifyEmailAPIView(AnonymousAPIView):
    @extend_schema(
        tags=["Auth"],
        summary="Подтвердить email кодом",
        request=EmailVerifySerializer,
        responses={
            200: inline_serializer(
                "VerifyEmailResponse",
                {
                    "ok": serializers.BooleanField(),
                    "user_id": serializers.IntegerField(),
                },
            ),
            400: OpenApiResponse(description="Код пустой, неверный или истек."),
            404: OpenApiResponse(description="Пользователь не найден."),
        },
    )
    def post(self, request):
        ser = EmailVerifySerializer(data=request.data)
        ser.is_valid(raise_exception=True)
        email = ser.validated_data["email"].strip().lower()
        code = ser.validated_data["code"].strip()

        user = Employee.objects.filter(email__iexact=email).first()
        if not user:
            return Response({"ok": False, "error": "user_not_found"}, status=404)
        if not code:
            return Response({"ok": False, "error": "empty_code"}, status=400)

        code_sent_at = getattr(user, "email_activation_sent_at", None) or getattr(
            user, "created_at", None
        )
        if code_sent_at and not user.email_verified:
            if timezone.now() - code_sent_at > timedelta(minutes=5):
                user.delete()
                return Response({"ok": False, "error": "expired"}, status=400)

        if not user.verify_email(code):
            return Response({"ok": False, "error": "invalid_code"}, status=400)

        user.is_active = True
        user._ldap_changes = {"is_active": True}
        user.save()

        return Response({"ok": True, "user_id": user.id}, status=200)