from rest_framework import decorators, response, status, viewsets

from apps.core.errors import ApiError, error_response
from apps.rbac.permissions import ActionPermission
from apps.workflows.engine import WorkflowEngine
from apps.workflows.models import Workflow, WorkflowStep, WorkflowTransition, WorkflowVersion
from apps.workflows.serializers import (
    WorkflowSerializer,
    WorkflowStepSerializer,
    WorkflowTransitionSerializer,
    WorkflowVersionSerializer,
)


class WorkflowViewSet(viewsets.ModelViewSet):
    queryset = Workflow.objects.all()
    serializer_class = WorkflowSerializer
    permission_classes = [ActionPermission]
    code_map = {
        "list": "workflow.view",
        "retrieve": "workflow.view",
        "create": "workflow.create",
        "update": "workflow.update",
        "partial_update": "workflow.update",
        "destroy": "workflow.update",
        "publish": "workflow.publish",
    }

    @decorators.action(detail=True, methods=["post"])
    def publish(self, request, pk=None):
        workflow = self.get_object()
        version = workflow.versions.filter(status="draft").order_by("-version").first()
        if version is None:
            return response.Response(
                error_response("WORKFLOW_INVALID", "No draft version to publish"),
                status=status.HTTP_400_BAD_REQUEST,
            )
        try:
            WorkflowEngine().publish(workflow, version)
        except ApiError as exc:
            return response.Response(error_response(exc.code, exc.message, exc.details), status=exc.status)
        return response.Response(WorkflowSerializer(workflow).data)


class WorkflowVersionViewSet(viewsets.ModelViewSet):
    queryset = WorkflowVersion.objects.all()
    serializer_class = WorkflowVersionSerializer
    permission_classes = [ActionPermission]
    filterset_fields = ["workflow"]
    code_map = {"create": "workflow.create", "update": "workflow.update", "partial_update": "workflow.update"}


class WorkflowStepViewSet(viewsets.ModelViewSet):
    queryset = WorkflowStep.objects.all()
    serializer_class = WorkflowStepSerializer
    permission_classes = [ActionPermission]
    filterset_fields = ["version", "key"]
    code_map = {"create": "workflow.create", "update": "workflow.update", "partial_update": "workflow.update"}


class WorkflowTransitionViewSet(viewsets.ModelViewSet):
    queryset = WorkflowTransition.objects.all()
    serializer_class = WorkflowTransitionSerializer
    permission_classes = [ActionPermission]
    filterset_fields = ["version"]
    code_map = {"create": "workflow.create", "update": "workflow.update", "partial_update": "workflow.update"}