# Custom Task Status Service Implementation

## Overview

Implemented the frontend service layer for managing custom task statuses in the VFX Project Management System. This service provides a clean API for interacting with the backend custom task status endpoints.

## Implementation Details

### File Created
- `frontend/src/services/customTaskStatus.ts`

### TypeScript Interfaces

The service includes comprehensive TypeScript interfaces for type safety:

#### Core Types
- **CustomTaskStatus**: Represents a custom task status with id, name, color, order, and is_default flag
- **SystemTaskStatus**: Represents built-in system statuses
- **AllTaskStatusesResponse**: Combined response containing both system and custom statuses

#### Request Types
- **CustomTaskStatusCreate**: For creating new statuses (name required, color optional)
- **CustomTaskStatusUpdate**: For updating statuses (all fields optional)
- **CustomTaskStatusReorder**: For reordering statuses (ordered list of status IDs)
- **CustomTaskStatusDelete**: For deleting statuses (optional reassignment)

#### Response Types
- **CustomTaskStatusResponse**: Standard response with message, status, and all_statuses
- **TaskStatusInUseError**: Error response when attempting to delete a status in use

### Service Methods

#### 1. getAllStatuses(projectId: number)
- **Purpose**: Retrieve all task statuses (system + custom) for a project
- **Endpoint**: `GET /projects/{projectId}/task-statuses`
- **Returns**: AllTaskStatusesResponse with system statuses, custom statuses, and default status ID
- **Requirements**: 1.1

#### 2. createStatus(projectId: number, status: CustomTaskStatusCreate)
- **Purpose**: Create a new custom task status
- **Endpoint**: `POST /projects/{projectId}/task-statuses`
- **Parameters**:
  - `name`: Status name (required)
  - `color`: Hex color code (optional, auto-assigned if not provided)
- **Returns**: CustomTaskStatusResponse with created status and all statuses
- **Requirements**: 1.2

#### 3. updateStatus(projectId: number, statusId: string, status: CustomTaskStatusUpdate)
- **Purpose**: Update an existing custom task status
- **Endpoint**: `PUT /projects/{projectId}/task-statuses/{statusId}`
- **Parameters**:
  - `name`: New status name (optional)
  - `color`: New hex color code (optional)
  - `is_default`: Set as default status (optional)
- **Returns**: CustomTaskStatusResponse with updated status and all statuses
- **Requirements**: 2.1

#### 4. deleteStatus(projectId: number, statusId: string, deleteData?: CustomTaskStatusDelete)
- **Purpose**: Delete a custom task status
- **Endpoint**: `DELETE /projects/{projectId}/task-statuses/{statusId}`
- **Parameters**:
  - `reassign_to_status_id`: Status ID to reassign tasks to (optional, required if status is in use)
- **Returns**: CustomTaskStatusResponse with remaining statuses
- **Requirements**: 3.1

#### 5. reorderStatuses(projectId: number, reorderData: CustomTaskStatusReorder)
- **Purpose**: Reorder custom task statuses
- **Endpoint**: `PATCH /projects/{projectId}/task-statuses/reorder`
- **Parameters**:
  - `status_ids`: Ordered array of status IDs
- **Returns**: CustomTaskStatusResponse with statuses in new order
- **Requirements**: 4.1

## API Integration

The service uses the centralized `apiClient` from `./api.ts` which handles:
- Authentication headers (JWT tokens)
- Base URL configuration
- Request/response interceptors
- Error handling

## Usage Example

```typescript
import { customTaskStatusService } from '@/services/customTaskStatus'

// Get all statuses
const statuses = await customTaskStatusService.getAllStatuses(projectId)

// Create a new status
const newStatus = await customTaskStatusService.createStatus(projectId, {
  name: 'Ready for Review',
  color: '#9333EA'
})

// Update a status
const updated = await customTaskStatusService.updateStatus(projectId, statusId, {
  name: 'In Review',
  is_default: true
})

// Reorder statuses
await customTaskStatusService.reorderStatuses(projectId, {
  status_ids: ['status-1', 'status-2', 'status-3']
})

// Delete a status
await customTaskStatusService.deleteStatus(projectId, statusId, {
  reassign_to_status_id: 'other-status-id'
})
```

## Testing

A test page has been created at `frontend/test-custom-task-status-service.html` that provides:
- Interactive UI for testing all service methods
- Login functionality
- Visual display of results
- Error handling demonstration

To test:
1. Start the backend server: `uvicorn main:app --reload` (from backend directory)
2. Start the frontend dev server: `npm run dev` (from frontend directory)
3. Open `http://localhost:5173/test-custom-task-status-service.html`
4. Click "Login as Admin" to authenticate
5. Test each service method using the provided UI

## Requirements Coverage

This implementation satisfies the following requirements from the custom task status specification:

- **Requirement 1.1**: Get all task statuses (system + custom)
- **Requirement 1.2**: Create custom task status
- **Requirement 2.1**: Update custom task status
- **Requirement 3.1**: Delete custom task status
- **Requirement 4.1**: Reorder custom task statuses

## Next Steps

The service is now ready to be integrated into UI components:
- Task 11: CustomTaskStatusManager component
- Task 12: Add/Edit status dialog
- Task 13: Status deletion with confirmation
- Task 14: Drag-and-drop reordering
- Task 15: Default status management

## Type Safety

All methods are fully typed with TypeScript interfaces, providing:
- Compile-time type checking
- IntelliSense support in IDEs
- Clear API contracts
- Reduced runtime errors

## Error Handling

The service relies on the apiClient's error handling, which:
- Catches HTTP errors
- Provides structured error responses
- Includes validation error details from the backend
- Supports error recovery patterns in UI components