from rest_framework import viewsets
from rest_framework.parsers import FormParser, JSONParser, MultiPartParser

from requests_app.models import Request as EmployeeRequest

from .viewsets import (
    RequestCommentsMixin,
    RequestCoreMixin,
    RequestNotificationsMixin,
    RequestStatisticsMixin,
    RequestVacationMixin,
    RequestWorkflowMixin,
)


class RequestViewSet(
    RequestCoreMixin,
    RequestCommentsMixin,
    RequestWorkflowMixin,
    RequestVacationMixin,
    RequestStatisticsMixin,
    RequestNotificationsMixin,
    viewsets.ModelViewSet,
):
    """ViewSet для заявок сотрудников.

    Обычный UI/API работает по строгим правилам участников:
    автор, прямые получатели и пользователи в копии.

    Поддерживаемые экшены:
      - POST /requests/{id}/approve/
      - POST /requests/{id}/reject/
      - POST /requests/{id}/cancel/
      - GET/POST /requests/{id}/comments/

    Raises:
        PermissionDenied: При нарушении правил доступа.
    """

    queryset = EmployeeRequest.objects.select_related(
        "employee",
        "approver",
        "department",
        "vacation_terms__recorded_by",
        "vacation_terms__finance_instruction",
    ).order_by("-created_at")
    parser_classes = (MultiPartParser, FormParser, JSONParser)