Add kanban position manage api

backend/tasks/tasks/serializers.py

@@ -1,5 +1,6 @@
 from rest_framework import serializers
-from ..models import Todo, RecurrenceTask, Habit
+from boards.models import ListBoard
+from tasks.models import Todo, RecurrenceTask, Habit
 
 class TaskSerializer(serializers.ModelSerializer):
     class Meta:
@@ -15,6 +16,42 @@ class TaskCreateSerializer(serializers.ModelSerializer):
         model = Todo
         exclude = ('tags',)
 
+class ChangeTaskOrderSerializer(serializers.Serializer):
+    list_board_id = serializers.IntegerField(
+        help_text='ID of the ListBoard for which the task order should be updated.'
+    )
+    todo_order = serializers.ListField(
+        child=serializers.IntegerField(),
+        required=False,
+        help_text='New order of Todo IDs in the ListBoard.'
+    )
+
+    def validate(self, data):
+        list_board_id = data.get('list_board_id')
+        todo_order = data.get('todo_order', [])
+
+        if not ListBoard.objects.filter(id=list_board_id).exists():
+            raise serializers.ValidationError('ListBoard does not exist.')
+
+        return data
+
+class ChangeTaskListBoardSerializer(serializers.Serializer):
+    todo_id = serializers.IntegerField()
+    new_list_board_id = serializers.IntegerField()
+    new_index = serializers.IntegerField(required=False)
+
+    def validate(self, data):
+        todo_id = data.get('todo_id')
+        new_list_board_id = data.get('new_list_board_id')
+        new_index = data.get('new_index')
+
+        if not Todo.objects.filter(id=todo_id, user=self.context['request'].user).exists():
+            raise serializers.ValidationError('Todo does not exist for the authenticated user.')
+
+        if not ListBoard.objects.filter(id=new_list_board_id).exists():
+            raise serializers.ValidationError('ListBoard does not exist.')
+
+        return data
 
 class RecurrenceTaskSerializer(serializers.ModelSerializer):
     class Meta:

backend/tasks/tasks/views.py

@@ -1,5 +1,12 @@
-from rest_framework import viewsets
+from django.shortcuts import get_object_or_404
+from django.db import IntegrityError
+from rest_framework import viewsets, status, serializers
+from rest_framework.decorators import action
 from rest_framework.permissions import IsAuthenticated
+from rest_framework.response import Response
+
+from .serializers import ChangeTaskListBoardSerializer, ChangeTaskOrderSerializer
+from boards.models import ListBoard, KanbanTaskOrder
 from tasks.models import Todo, RecurrenceTask, Habit
 from tasks.tasks.serializers import (TaskCreateSerializer,
                                      TaskSerializer,
@@ -24,6 +31,90 @@ class TodoViewSet(viewsets.ModelViewSet):
             return TaskCreateSerializer
         return TaskSerializer
 
+    def create(self, request, *args, **kwargs):
+        try:
+            new_task_data = request.data
+            new_task_data['user'] = self.request.user
+            serializer = self.get_serializer(data=new_task_data)
+            serializer.is_valid(raise_exception=True)
+            self.perform_create(serializer)
+            headers = self.get_success_headers(serializer.data)
+            return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
+
+        except IntegrityError as e:
+            return Response({'error': 'IntegrityError - Duplicate Entry'}, status=status.HTTP_400_BAD_REQUEST)
+
+        except Exception as e:
+            return Response({'error': str(e)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
+
+    @action(detail=False, methods=['put'])
+    def change_task_order(self, request):
+        try:
+            serializer = ChangeTaskOrderSerializer(data=request.data)
+            serializer.is_valid(raise_exception=True)
+
+            list_board_id = serializer.validated_data['list_board_id']
+            new_order = serializer.validated_data.get('todo_order', [])
+
+            list_board = get_object_or_404(ListBoard, id=list_board_id)
+            kanban_order, created = KanbanTaskOrder.objects.get_or_create(list_board=list_board)
+            kanban_order.todo_order = new_order
+            kanban_order.save()
+
+            return Response({'message': 'Task order updated successfully'})
+
+        except serializers.ValidationError as e:
+            return Response({'error': str(e)}, status=status.HTTP_400_BAD_REQUEST)
+
+        except Exception as e:
+            return Response({'error': str(e)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
+
+    @action(detail=False, methods=['put'])
+    def change_task_list_board(self, request):
+        try:
+            serializer = ChangeTaskListBoardSerializer(data=request.data, context={'request': request})
+            serializer.is_valid(raise_exception=True)
+
+            todo_id = serializer.validated_data['todo_id']
+            new_list_board_id = serializer.validated_data['new_list_board_id']
+            new_index = serializer.validated_data.get('new_index')
+
+            todo_id = request.data.get('todo_id')
+            new_list_board_id = request.data.get('new_list_board_id')
+
+            todo = get_object_or_404(Todo, id=todo_id, user=self.request.user)
+            old_list_board = todo.list_board
+
+            # Remove todoId from todo_order of the old list board
+            old_kanban_order, _ = KanbanTaskOrder.objects.get_or_create(list_board=old_list_board)
+            old_kanban_order.todo_order = [t_id for t_id in old_kanban_order.todo_order if t_id != todo.id]
+            old_kanban_order.save()
+
+            # Get the index to insert the todo in the new list board's todo_order
+            new_list_board = get_object_or_404(ListBoard, id=new_list_board_id)
+            new_kanban_order, _ = KanbanTaskOrder.objects.get_or_create(list_board=new_list_board)
+            
+            # Index where todo need to insert (start from 0)
+            new_index = request.data.get('new_index', None)
+
+            if new_index is not None and 0 <= new_index <= len(new_kanban_order.todo_order):
+                new_kanban_order.todo_order.insert(new_index, todo.id)
+            else:
+                new_kanban_order.todo_order.append(todo.id)
+
+            new_kanban_order.save()
+
+            todo.list_board = new_list_board
+            todo.save()
+
+            return Response({'message': 'ListBoard updated successfully'})
+
+        except serializers.ValidationError as e:
+            return Response({'error': str(e)}, status=status.HTTP_400_BAD_REQUEST)
+
+        except Exception as e:
+            return Response({'error': str(e)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
+    
 
 class RecurrenceTaskViewSet(viewsets.ModelViewSet):
     queryset = RecurrenceTask.objects.all()