import logging

from django.contrib.auth import get_user_model

from drf_spectacular.utils import extend_schema, OpenApiResponse
from rest_framework import status
from rest_framework.authtoken.models import Token
from rest_framework.generics import GenericAPIView
from rest_framework.permissions import AllowAny
from rest_framework.response import Response

from apps.account.serializers import ExchangeTokenSerializer
from utils import absolute_url
from utils.redis import OnlineClassTokenManager


from django.utils import timezone
from utils.ip_helper import get_client_ip

logger = logging.getLogger(__name__)
UserModel = get_user_model()


def detect_device_os(user_agent):
    if not user_agent:
        return None
    ua = user_agent.lower()
    if 'android' in ua:
        return 'android'
    if 'iphone' in ua or 'ipad' in ua or 'ios' in ua:
        return 'apple'
    if any(k in ua for k in ['mozilla', 'chrome', 'safari', 'windows', 'macintosh', 'linux']):
        return 'web'
    return None


class ExchangeTokenAPIView(GenericAPIView):
    """
    تبدیل temporary token به اطلاعات کاربر برای ورود از اپ موبایل
    """
    permission_classes = [AllowAny]
    serializer_class = ExchangeTokenSerializer

    @extend_schema(
        summary="Exchange temporary token for user authentication",
        description="Exchange a one-time temporary token (issued by mobile app) for a real auth token and user info.",
        request=ExchangeTokenSerializer,
        responses={
            200: OpenApiResponse(description="Token exchanged successfully. Returns auth token and user details."),
            400: OpenApiResponse(description="Invalid request — token not provided or malformed."),
            404: OpenApiResponse(description="Token not found, expired, or user does not exist."),
        }
    )
    def post(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)

        temp_token = serializer.validated_data['temp_token']

        # دریافت اطلاعات از Redis/Cache
        manager = OnlineClassTokenManager()
        try:
            token_data = manager.get_payload(temp_token)
        except Exception:
            return Response({
                'success': False,
                'message': 'توکن نامعتبر یا منقضی شده است'
            }, status=status.HTTP_404_NOT_FOUND)

        user_id = token_data.get('user_id')
        if not user_id:
            return Response({
                'success': False,
                'message': 'توکن نامعتبر است'
            }, status=status.HTTP_400_BAD_REQUEST)

        # دریافت کاربر
        try:
            user = UserModel.objects.get(id=user_id)
        except UserModel.DoesNotExist:
            return Response({
                'success': False,
                'message': 'کاربر یافت نشد'
            }, status=status.HTTP_404_NOT_FOUND)

        # حذف توکن موقت (one-time use)
        manager.delete_token(temp_token)

        # دریافت یا تولید Token واقعی کاربر
        auth_token, _ = Token.objects.get_or_create(user=user)

        client_ip = get_client_ip(request)
        user_agent = request.META.get('HTTP_USER_AGENT', '')
        device_os = token_data.get('device_os')
        if not device_os and user_agent:
            device_os = detect_device_os(user_agent)

        user.last_login = timezone.now()
        if client_ip:
            user.client_ip = client_ip
        if user_agent:
            user.user_agent = user_agent
        if device_os:
            user.device_os = device_os
        user.save()

        user.login_history.create(
            ip=client_ip,
            user_agent=user_agent,
            device_os=user.device_os or device_os,
        )

        # دریافت avatar URL
        avatar_url = None
        if hasattr(user, 'avatar') and user.avatar:
            try:
                avatar_url = absolute_url(user.avatar.url)
            except Exception:
                avatar_url = None

        # برگرداندن اطلاعات کاربر با token واقعی
        return Response({
            'success': True,
            'message': 'ورود موفق',
            'token': auth_token.key,
            'user': {
                'id': user.id,
                'fullname': user.get_full_name() or user.username or '',
                'email': user.email or '',
                'avatar': avatar_url
            }
        }, status=status.HTTP_200_OK)