from django.shortcuts import get_object_or_404

from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework import status

from .models import *

from django_filters.rest_framework import DjangoFilterBackend
from rest_framework.filters import OrderingFilter
from rest_framework.generics import ListAPIView
from .serializers import ProjectListViewSerializer, ProjectCreateSerializer, ProjectTeamSerializer
from .paginations import ProjectPagination
from .filters import ProjectFilter
from .services import *

from django.db import transaction

from notifications.services import *


class ProjectListView(ListAPIView):
    queryset = Project.objects.filter(is_published=True).order_by('-created_at')
    serializer_class = ProjectListViewSerializer
    pagination_class = ProjectPagination
    filterset_class = ProjectFilter
    filter_backends = [DjangoFilterBackend, OrderingFilter]
    ordering_fields = ['view_count', 'like_count', 'scrap_count', 'created_at']  # 허용할 필드 추천순 제외
    ordering = ['-created_at']  # 기본 정렬은 최신순

class ProjectCreateAPIView(APIView):
    @transaction.atomic
    def post(self, request):
        user = request.user
        serializer = ProjectCreateSerializer(data=request.data, context={"request": request})
        if serializer.is_valid():
            serializer.save()
            return Response({"message": "create project success"}, status=status.HTTP_200_OK)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
    
class ProjectTeamManageAPIView(APIView):
    # 팀원 초대 및 알림
    @transaction.atomic
    def post(self, request, pk):
        user = request.user
        project = get_object_or_404(Project, id=pk)
        if user != project.owner:
            return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
        nickname = request.data.get('nickname')
        new_member = get_object_or_404(User, nickname=nickname)
        if ProjectTeamList.objects.filter(project=project, user=new_member).exists():
            return Response({"message": "already team member"}, status=status.HTTP_400_BAD_REQUEST)
        new_notification = NotifiationService.create_notification(user=new_member, note_type=NotificationType.INVITE)
        ProjectInvitationService.create_project_invitation(
            project=project,
            from_user=user, 
            to_user=new_member,
            notification=new_notification
            )
        return Response({"message": "invite success"}, status=status.HTTP_200_OK)
    
    # 팀원 추방
    @transaction.atomic
    def delete(self, request, pk):
        user = request.user
        project = get_object_or_404(Project, id=pk)
        if user != project.owner:
            return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
        nickname = request.data.get('nickname')
        member = get_object_or_404(User, nickname=nickname)
        user_in_project = get_object_or_404(ProjectTeamList, project=project, user=member)
        user_in_project.delete()
        return Response({"message": "delete user in project success"})
    
class ProjectDeleteAPIView(APIView):
    @transaction.atomic
    def delete(self, request, pk):
        user = request.user
        project = get_object_or_404(Project, id=pk)
        if user != project.owner:
            return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
        project.delete()
        return Response({"message": "delete success"}, status=status.HTTP_200_OK)
        
class ProjectSetRepresentAPIView(APIView):
    @transaction.atomic
    def patch(self, request, pk):
        user = request.user
        project = get_object_or_404(Project, id=pk)
        if user != project.owner:
            return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
        if before_represent := Project.objects.filter(owner=user, is_represent=True).first():
            before_represent.is_represent = False
            before_represent.save()
        project.is_represent = True
        project.save()
        return Response({"message": "change represent success"}, status=status.HTTP_200_OK)


class ProjectSetPublishAPIView(APIView):
    @transaction.atomic
    def patch(self, request, pk):
        user = request.user
        project = get_object_or_404(Project, id=pk)
        if user != project.owner:
            return Response({"message": "Not owner"}, status=status.HTTP_403_FORBIDDEN)
        project.is_published = True
        project.save()
        return Response({"message": "publish success"}, status=status.HTTP_200_OK)

class ProjectChangeState(APIView):
    @transaction.atomic
    def patch(self, request, pk):
        project = get_object_or_404(Project, pk=pk)
        user = request.user
        action_type = request.query_params.get('type')
        try:
            if ProjectBeforeRelCheckService.check_user_project_rel(action_type, project, user):
                return Response({"message": "already done"}, status=status.HTTP_400_BAD_REQUEST)
        except ValueError as e:
            return Response({'message': str(e)}, status=status.HTTP_400_BAD_REQUEST)
        return self._handle_action(action_type, project, user, add=True)

    @transaction.atomic
    def delete(self, request, pk):
        project = get_object_or_404(Project, pk=pk)
        user = request.user
        action_type = request.query_params.get('type')
        try:
            if not ProjectBeforeRelCheckService.check_user_project_rel(action_type, project, user):
                return Response({"message": "never done before"}, status=status.HTTP_400_BAD_REQUEST)
        except ValueError as e:
            return Response({'message': str(e)}, status=status.HTTP_400_BAD_REQUEST)
        return self._handle_action(action_type, project, user, add=False)

    def _handle_action(self, action_type, project, user, add=True):
        if not action_type:
            return Response({'message': 'Missing action type'}, status=status.HTTP_400_BAD_REQUEST)

        try:
            ProjectStateChangeService.change_user_project_rel(action_type, project, user, add)
            ProjectStateChangeService.change_count_project_state(action_type, project, add)
        except ValueError as e:
            return Response({'message': str(e)}, status=status.HTTP_400_BAD_REQUEST)

        return Response({
            'message': f'{action_type} {"added" if add else "removed"}'
        }, status=status.HTTP_200_OK)

class ProjectInvitationAPIView(APIView):
    # 팀원 초대 수락/거절
    @transaction.atomic
    def post(self, request):
        accept = request.data['accept']
        project_invitation = get_object_or_404(ProjectInvitation, id=request.data['project_invitation_id'])
        new_member = project_invitation.to_user
        project = project_invitation.project
        if request.user != new_member:
            return Response({"message": "Not account owner"}, status=status.HTTP_403_FORBIDDEN)
        if project_invitation.status != InvitationStatus.PENDING:
            return Response({"message": "already handled invitation"}, status=status.HTTP_400_BAD_REQUEST)
        if accept:
            project_invitation.status = InvitationStatus.ACCEPTED
            project_invitation.save()
            serializer = ProjectTeamSerializer(data={'user':new_member.id, 'project':project.id})
            if serializer.is_valid():
                serializer.save()
                return Response({"message": "invitation accepted"}, status=status.HTTP_200_OK)
        else:
            project_invitation.status = InvitationStatus.REJECTED
            project_invitation.save()
            return Response({"message": "invitation rejected"}, status=status.HTTP_200_OK)