from rest_framework.response import Response
from rest_framework import serializers
from rest_framework.mixins import CreateModelMixin, DestroyModelMixin, ListModelMixin, RetrieveModelMixin, UpdateModelMixin
from apps.wf.serializers import CustomFieldSerializer, StateSerializer, TicketCreateSerializer, TicketSerializer, TransitionSerializer, WorkflowSerializer
from django.shortcuts import render
from rest_framework.viewsets import GenericViewSet, ModelViewSet
from rest_framework.decorators import action, api_view
from apps.wf.models import CustomField, Ticket, Workflow, State, Transition
from apps.system.mixins import CreateUpdateCustomMixin, CreateUpdateModelAMixin, OptimizationMixin
from apps.wf.services import WfService
from rest_framework.exceptions import APIException

# Create your views here.
class WorkflowViewSet(CreateUpdateModelAMixin, ModelViewSet):
    perms_map = {'get': '*', 'post': 'workflow_create',
                 'put': 'workflow_update', 'delete': 'workflow_delete'}
    queryset = Workflow.objects.all()
    serializer_class = WorkflowSerializer
    search_fields = ['name', 'description']
    filterset_fields = []
    ordering_fields = ['create_time']
    ordering = ['-create_time']    

    @action(methods=['get'], detail=True, perms_map={'get':'workflow_update'}, pagination_class=None, serializer_class=StateSerializer)
    def states(self, request, pk=None):
        """
        工作流下的状态节点
        """
        wf = self.get_object()
        serializer = self.serializer_class(instance=WfService.get_worlflow_states(wf), many=True)
        return Response(serializer.data)
    
    @action(methods=['get'], detail=True, perms_map={'get':'workflow_update'}, pagination_class=None, serializer_class=TransitionSerializer)
    def transitions(self, request, pk=None):
        """
        工作流下的流转规则
        """
        wf = self.get_object()
        serializer = self.serializer_class(instance=WfService.get_workflow_transitions(wf), many=True)
        return Response(serializer.data)
    
    @action(methods=['get'], detail=True, perms_map={'get':'workflow_update'}, pagination_class=None, serializer_class=CustomFieldSerializer)
    def customfields(self, request, pk=None):
        """
        工作流下的自定义字段
        """
        wf = self.get_object()
        serializer = self.serializer_class(instance=CustomField.objects.filter(workflow=wf), many=True)
        return Response(serializer.data)
    
    @action(methods=['get'], detail=True, perms_map={'get':'workflow_init'})
    def init(self, request, pk=None):
        """
        新建工单初始化
        """
        ret={}
        wf = self.get_object()
        start_state = WfService.get_workflow_start_state(wf)
        transitions = WfService.get_state_transitions(start_state)
        ret['workflow'] = pk
        ret['transitions'] = TransitionSerializer(instance=transitions, many=True).data
        field_list = CustomFieldSerializer(instance=WfService.get_workflow_custom_fields(wf), many=True).data
        ret['field_list'] = field_list
        return Response(ret)

class StateViewSet(CreateModelMixin, UpdateModelMixin, RetrieveModelMixin, DestroyModelMixin, GenericViewSet):
    perms_map = {'*':'*'}
    queryset = State.objects.all()
    serializer_class = StateSerializer
    search_fields = ['name']
    filterset_fields = ['workflow']
    ordering = ['sort']

class TransitionViewSet(CreateModelMixin, UpdateModelMixin, RetrieveModelMixin, DestroyModelMixin, GenericViewSet):
    perms_map = {'*':'*'}
    queryset = Transition.objects.all()
    serializer_class = TransitionSerializer
    search_fields = ['name']
    filterset_fields = ['workflow']
    ordering = ['id']

class CustomFieldViewSet(CreateModelMixin, UpdateModelMixin, RetrieveModelMixin, DestroyModelMixin, GenericViewSet):
    perms_map = {'*':'*'}
    queryset = CustomField.objects.all()
    serializer_class = CustomFieldSerializer
    search_fields = ['field_name']
    filterset_fields = ['workflow', 'field_type']
    ordering = ['sort']

class TicketViewSet(OptimizationMixin, CreateUpdateCustomMixin, CreateModelMixin, ListModelMixin, RetrieveModelMixin, GenericViewSet):
    perms_map = {'*':'*'}
    queryset = Ticket.objects.all()
    serializer_class = TicketSerializer
    search_fields = ['title']
    filterset_fields = ['workflow', 'state']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action == 'create':
            return TicketCreateSerializer
        return super().get_serializer_class()

    def create(self, request, *args, **kwargs):
        """
        新建工单
        """
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        start_state = WfService.get_workflow_start_state(serializer.data['workflow'])
        transition = Transition.objects.get(pk=serializer.data['transition'])
        ticket_data = serializer.data['ticket_data']
        if transition.field_require_check:
            for key, value in start_state.state_fields.items(): #校验必填项
                if value == 2:
                    if key not in ticket_data or not ticket_data[key]:
                        raise APIException('字段{}必填'.format(key))
        ticket = serializer.save()
        next_state = WfService.get_next_state_id_by_transition_and_ticket_info(ticket=ticket, transition=transition)
        participant_info = WfService.get_ticket_state_participant_info(state=next_state, ticket=ticket, ticket_data=ticket.ticket_data)
        destination_participant_type = participant_info.get('destination_participant_type', 0)
        destination_participant = participant_info.get('destination_participant', '')
        multi_all_person = participant_info.get('multi_all_person', '{}')  # 多人需要全部处理情况
        sn = WfService.get_ticket_sn(ticket.workflow)
        if next_state.type == State.STATE_TYPE_END:
            act_state = Ticket.TICKET_ACT_STATE_FINISH
        elif next_state.type == State.STATE_TYPE_START:
            pass
    
    @action(methods=['get'], detail=True, perms_map={'get':'*'})
    def flowsteps(self, request, pk=None):
        """
        工单流转step, 用于显示当前状态的step图(线性结构)
        """
        ticket = self.get_object()
        steps = WfService.get_ticket_steps(ticket)
        return Response(StateSerializer(instance=steps, many=True).data)
    
    @action(methods=['get'], detail=True, perms_map={'get':'*'})
    def transitions(self, request, pk=None):
        """
        获取工单可执行的操作
        """
        ticket = self.get_object()
        transitions = WfService.get_ticket_transitions(ticket)
        return Response(TransitionSerializer(instance=transitions, many=True).data)