from __future__ import annotations

from django.conf import settings
from django.http import FileResponse, Http404
from django.urls import reverse
from django.utils import timezone
from drf_spectacular.utils import extend_schema
from rest_framework import mixins, status, viewsets
from rest_framework.decorators import action
from rest_framework.permissions import IsAuthenticated
from rest_framework.response import Response
from rest_framework.views import APIView

from apps.reports.api.serializers import (
    ReportExportCreateSerializer,
    ReportExportJobSerializer,
)
from apps.reports.models import ReportExportJob
from apps.reports.services import (
    build_chart_report,
    build_day_details_report,
    build_table_report,
    load_report_filters,
)
from apps.reports.tasks import generate_report_export_task


class ReportChartView(APIView):
    permission_classes = [IsAuthenticated]

    @extend_schema(responses=dict)
    def get(self, request):
        return Response(build_chart_report(request.user, request.query_params))


class ReportTableView(APIView):
    permission_classes = [IsAuthenticated]

    @extend_schema(responses=dict)
    def get(self, request):
        return Response(build_table_report(request.user, request.query_params))


class ReportDayDetailsView(APIView):
    permission_classes = [IsAuthenticated]

    @extend_schema(responses=dict)
    def get(self, request):
        return Response(build_day_details_report(request.user, request.query_params))


class ReportExportJobViewSet(
    mixins.CreateModelMixin,
    mixins.ListModelMixin,
    mixins.RetrieveModelMixin,
    viewsets.GenericViewSet,
):
    permission_classes = [IsAuthenticated]
    serializer_class = ReportExportJobSerializer

    def get_queryset(self):
        return ReportExportJob.objects.filter(requesting_user=self.request.user, is_deleted=False)

    @extend_schema(request=ReportExportCreateSerializer, responses=ReportExportJobSerializer)
    def create(self, request, *args, **kwargs):
        serializer = ReportExportCreateSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        filters = load_report_filters(request.user, serializer.validated_data)

        job = ReportExportJob.objects.create(
            requesting_user=request.user,
            workspace=filters.workspace,
            export_type=serializer.validated_data["export_type"],
            filters={
                "workspace": str(filters.workspace.id),
                "period": filters.period,
                "from_date": filters.from_date.isoformat(),
                "to_date": filters.to_date.isoformat(),
                "user": filters.user_id,
                "client": filters.client_id,
                "project": filters.project_id,
                "tags": filters.tag_ids,
                "language": serializer.validated_data.get("language", "en"),
            },
            status=ReportExportJob.Status.PENDING,
        )
        generate_report_export_task.delay(str(job.id))
        output = ReportExportJobSerializer(job)
        return Response(output.data, status=status.HTTP_202_ACCEPTED)

    @action(detail=True, methods=["get"], url_path="download")
    def download(self, request, pk=None):
        job = self.get_object()
        if job.status != ReportExportJob.Status.COMPLETED or not job.file:
            raise Http404("Export file is not available.")
        if job.expires_at and job.expires_at <= timezone.now():
            raise Http404("Export file has expired.")
        response = FileResponse(
            job.file.open("rb"),
            as_attachment=True,
            filename=job.file_name or job.file.name.split("/")[-1],
        )
        return response


def build_export_action_url(job: ReportExportJob) -> str:
    path = reverse("report-export-job-download", kwargs={"pk": job.id})
    if settings.BASE_URL:
        return f"{settings.BASE_URL.rstrip('/')}{path}"
    return path