# Presence Activity API Documentation

## Overview

The Presence Activity API allows users to manage their current activities (e.g., gaming, music, workouts) with automatic expiration through a lease-based system. Activities can be created, updated, and deleted, with support for flexible metadata and both system-generated and user-defined identifiers.

This service is handled by the DysonNetwork.Pass, when using with the gateway, replace the `/api` with the `/pass`

## Key Features

- **Lease-Based Expiration**: Activities automatically expire within 1-60 minutes unless renewed
- **Flexible Identity**: Support for both autogenerated GUIDs and user-defined ManualIds
- **Extensible Metadata**: JSON-stored metadata dictionary for custom developer data
- **Soft Deletion**: Activities are soft-deleted and filtered automatically
- **Performance Optimized**: Cached active activities with 1-minute expiration
- **Authentication Required**: All endpoints require valid user authentication

## API Endpoints

### Base URL: `/api/activities`

### Authentication
All endpoints require `[Authorize]` header. User context is automatically extracted.

---

## Get Active Activities

Retrieve all currently active (non-expired) presence activities for the authenticated user.

**Endpoint:** `GET /api/activities`

**Response:**
```json
[
  {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "type": "Gaming",
    "manualId": "game-session-1",
    "title": "Playing Cyberpunk 2077",
    "subtitle": "Night City Exploration",
    "caption": "Missions completed: 15",
    "meta": {
      "appName": "Cyberpunk 2077",
      "platform": "Steam",
      "customProperty": "additional data"
    },
    "leaseMinutes": 10,
    "leaseExpiresAt": "2024-01-15T14:30:00Z",
    "accountId": "user-guid",
    "createdAt": "2024-01-15T14:25:00Z",
    "updatedAt": "2024-01-15T14:25:00Z",
    "deletedAt": null
  }
]
```

**Common Response Codes:**
- `200 OK` - Success, returns array of active activities
- `401 Unauthorized` - Invalid or missing authentication

---

## Create New Activity

Create a new presence activity with a configurable lease period.

**Endpoint:** `POST /api/activities`

**Request Body:**
```json
{
  "type": "Gaming",
  "manualId": "my-game-session",
  "title": "Playing Cyberpunk 2077",
  "subtitle": "Night City Mission",
  "caption": "Currently exploring downtown",
  "meta": {
    "appName": "Cyberpunk 2077",
    "platform": "Steam",
    "difficulty": "Hard",
    "mods": ["mod1", "mod2"]
  },
  "leaseMinutes": 15
}
```

**Response:** Returns the created `SnPresenceActivity` object with populated fields.

**Field Details:**
- `type`: PresenceType enum (Unknown, Gaming, Music, Workout)
- `manualId`: Optional user-defined string identifier
- `title`, `subtitle`, `caption`: Display strings (max 4096 chars each)
- `meta`: Optional `Dictionary<string, object>` for custom data
- `leaseMinutes`: 1-60 minutes (default: 5)

**Response Codes:**
- `200 OK` - Activity created successfully
- `400 Bad Request` - Invalid lease minutes or malformed data
- `401 Unauthorized` - Invalid authentication

---

## Update Activity

Update an existing activity using either its GUID or ManualId. Only provided fields are updated.

**Endpoint:** `PUT /api/activities`

**Query Parameters:** (one required)
- `id` - System-generated GUID (string)
- `manualId` - User-defined identifier (string)

**Request Body:** (all fields optional)
```json
{
  "title": "Updated: Playing Cyberpunk 2077",
  "meta": {
    "appName": "Cyberpunk 2077",
    "platform": "Steam",
    "newProperty": "updated data"
  },
  "leaseMinutes": 20
}
```

**Response:** Returns the updated `SnPresenceActivity` object.

**Response Codes:**
- `200 OK` - Activity updated successfully
- `400 Bad Request` - Missing or invalid ID parameters
- `401 Unauthorized` - Invalid authentication
- `404 Not Found` - Activity not found or doesn't belong to user

**Example cURL:**
```bash
# Update by ManualId
curl -X PUT "/api/activities?manualId=my-game-session" \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{"leaseMinutes": 20}'

# Update by GUID
curl -X PUT "/api/activities?id=550e8400-e29b-41d4-a716-446655440000" \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{"title": "Updated Title"}'
```

---

## Delete Activity

Soft-delete an activity using either GUID or ManualId.

**Endpoint:** `DELETE /api/activities`

**Query Parameters:** (one required)
- `id` - System-generated GUID (string)
- `manualId` - User-defined identifier (string)

**Request Body:** None

**Response:** No content (204)

**Response Codes:**
- `204 No Content` - Activity deleted successfully
- `400 Bad Request` - Missing or invalid ID parameters
- `401 Unauthorized` - Invalid authentication
- `404 Not Found` - Activity not found or doesn't belong to user

**Example cURL:**
```bash
# Delete by ManualId
curl -X DELETE "/api/activities?manualId=my-game-session" \
  -H "Authorization: Bearer <token>"
```

---

## Additional Endpoint

### Get Activities by Account ID

**Endpoint:** `GET /api/activities/{accountId:guid}`

For administrative or debugging purposes. Returns activities for the specified account ID, regardless of authentication.

---

## Data Models

### PresenceType Enum
```csharp
public enum PresenceType
{
    Unknown,
    Gaming,
    Music,
    Workout
}
```

### SnPresenceActivity
```csharp
public class SnPresenceActivity : ModelBase
{
    public Guid Id { get; set; } // System-generated GUID
    public PresenceType Type { get; set; }
    public string? ManualId { get; set; } // User-defined ID
    public string? Title { get; set; }
    public string? Subtitle { get; set; }
    public string? Caption { get; set; }
    public Dictionary<string, object>? Meta { get; set; } // JSON metadata
    public int LeaseMinutes { get; set; } // Lease duration
    public Instant LeaseExpiresAt { get; set; } // Expiration timestamp

    // Inherited from ModelBase
    public Guid AccountId { get; set; }
    public Instant CreatedAt { get; set; }
    public Instant UpdatedAt { get; set; }
    public Instant? DeletedAt { get; set; } // Soft deletion
}
```

## Behavior & Constraints

### Lease Expiration
- Activities automatically expire when `SystemClock.Instance.GetCurrentInstant() > LeaseExpiresAt`
- Expiry is checked in database queries, so expired activities are filtered out of GET operations
- Clients must periodically update/renew leases to keep activities active

### ID Flexibility
- **ManualId**: User-defined string, unique within a user's activities
- **GUID**: System-generated, always unique, returned in API responses
- Both can be used interchangeably for updates and deletion

### Performance Optimizations
- Active activities are cached for 1 minute to handle frequent updates
- Cache is invalidated on create/update/delete operations
- Database queries filter expired activities automatically

### Security
- All operations are scoped to the authenticated user's account
- Users can only manage their own activities
- Invalid or expired authentication tokens return 401 Unauthorized

### Data Storage
- Activities are stored in PostgreSQL with JSONB metadata support
- Soft deletion uses timestamp rather than hard removal
- EF Core middleware automatically handles CreatedAt/UpdatedAt timestamps

## Usage Examples

### Gaming Session Management
```javascript
// Start gaming session
const activity = await fetch('/api/activities', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    type: 'Gaming',
    manualId: 'game-session-1',
    title: 'Playing Cyberpunk 2077',
    meta: { appId: 'cyberpunk2077', mods: ['photorealistic'] },
    leaseMinutes: 15
  })
});

// Update progress (extend lease)
await fetch('/api/activities?manualId=game-session-1', {
  method: 'PUT',
  body: JSON.stringify({
    title: 'Playing Cyberpunk 2077 - Level 25',
    leaseMinutes: 15
  })
});

// End session
await fetch('/api/activities?manualId=game-session-1', {
  method: 'DELETE'
});
```

### Metadata Extension
```javascript
// Rich metadata support
const activity = {
  type: 'Music',
  manualId: 'spotify-session',
  title: 'Listening to Electronic',
  meta: {
    spotifyTrackId: '1Je1IMUlBXcx1FzbcXRuWw',
    artist: 'Purity Ring',
    album: 'Shrines',
    duration: 240000, // milliseconds
    custom: { userRating: 5, genre: 'Electronic' }
  },
  leaseMinutes: 30
};
```

## Error Handling

Common error responses follow REST API conventions:

```json
{
  "type": "Microsoft.AspNetCore.Mvc.ValidationProblemDetails",
  "title": "One or more validation errors occurred.",
  "status": 400,
  "errors": {
    "leaseMinutes": ["Lease minutes must be between 1 and 60."]
  }
}
```

## Implementation Notes

- Built with ASP.NET Core and Entity Framework Core
- Uses NodaTime for precise timestamp handling
- PostgreSQL JSONB for flexible metadata storage
- Integration with existing authentication and caching systems
- Follows established project patterns for soft deletion and audit trails
