live-activity-generator

# Live Activity Generator

Generate a complete ActivityKit Live Activity implementation with Dynamic Island layouts, Lock Screen presentation, activity lifecycle management, and push-to-update support.

## When This Skill Activates

Use this skill when the user:
- Asks to "add Live Activities" or "add a Live Activity"
- Mentions "Dynamic Island" layouts
- Wants real-time status updates on the Lock Screen
- Asks about "ActivityKit" or "ActivityAttributes"
- Mentions "push-to-update" for live activities
- Wants to show ongoing progress (delivery tracking, sports scores, timers, workouts)

## Pre-Generation Checks

### 1. Project Context Detection
- [ ] Check for existing ActivityKit implementations
- [ ] Check for an existing widget extension target
- [ ] Verify deployment target is iOS 16.1+
- [ ] Identify source file locations

### 2. Conflict Detection
Search for existing Live Activity code:
```
Glob: **/*Activity*.swift, **/*LiveActivity*.swift
Grep: "ActivityKit" or "ActivityAttributes" or "ActivityConfiguration"
```

If an existing widget extension is found:
- Ask if the Live Activity should be added to the existing widget bundle
- Check for existing `WidgetBundle` to extend

If Live Activity code already exists:
- Ask user whether to replace or extend

### 3. Required Capabilities

**Live Activities require:**
- iOS 16.1+ deployment target
- `NSSupportsLiveActivities` set to `YES` in Info.plist
- A widget extension target (can share with existing WidgetKit widgets)
- For push updates: `NSSupportsLiveActivitiesFrequentUpdates` (optional, iOS 16.2+)

## Configuration Questions

Ask user via AskUserQuestion:

1. **What is the Live Activity for?** (freeform)
   - Examples: delivery tracking, sports score, workout timer, ride-sharing, food order
   - This determines the attribute fields and content state

2. **What data should appear on the Lock Screen?** (freeform)
   - Static data (set at start, does not change): e.g., restaurant name, order number
   - Dynamic data (updated over time): e.g., ETA, driver location, score

3. **Dynamic Island layout needs?**
   - Compact (leading + trailing) only
   - Expanded (leading, trailing, center, bottom) only
   - Both compact and expanded (recommended)

4. **Push-to-update support?**
   - Yes -- server can update the activity remotely via APNs
   - No -- updates only from the app process

5. **Alert configuration when ending?**
   - Yes -- show a final alert on the Lock Screen when the activity ends
   - No -- dismiss silently

## Generation Process

### Step 1: Determine File Locations

Check project structure:
- If a widget extension target exists, add files there
- Otherwise, instruct user to create a Widget Extension target first

For the activity manager (lives in the main app target):
- If `Sources/` exists --> `Sources/LiveActivity/`
- If `App/` exists --> `App/LiveActivity/`
- Otherwise --> `LiveActivity/`

For the widget extension views:
- Place inside the existing widget extension directory (e.g., `MyAppWidgets/`)

### Step 2: Create Core Files

Generate these files based on configuration answers:

1. **`{Name}ActivityAttributes.swift`** -- Shared between app and widget extension
   - `ActivityAttributes` struct with static properties
   - Nested `ContentState` with dynamic properties
2. **`{Name}LiveActivityView.swift`** -- Widget extension file
   - `ActivityConfiguration` with Lock Screen, Dynamic Island layouts
3. **`{Name}ActivityManager.swift`** -- Main app target file
   - Protocol-based manager for start, update, end, and push token handling

### Step 3: Generate Code from Templates

Use the templates in **templates.md** and customize based on user answers:
- Replace placeholder attribute names with real fields
- Configure Dynamic Island regions based on layout choice
- Include or exclude push-to-update code
- Include or exclude alert configuration

## Info.plist Required

### Main App Target
```xml
<key>NSSupportsLiveActivities</key>
<true/>

<!-- Optional: for frequent push updates (iOS 16.2+) -->
<key>NSSupportsLiveActivitiesFrequentUpdates</key>
<true/>
```

## Output Format

After generation, provide:

### Files Created

```
Sources/LiveActivity/
├── {Name}ActivityAttributes.swift     # Shared: attributes + content state
└── {Name}ActivityManager.swift        # Main app: lifecycle management

MyAppWidgets/
├── {Name}LiveActivityView.swift       # Widget ext: all Live Activity UI
└── (update WidgetBundle if needed)
```

### Integration Steps

**1. Add the widget extension target (if not present):**
- File > New > Target > Widget Extension
- Ensure "Include Live Activity" is checked

**2. Share the attributes file between targets:**
The `{Name}ActivityAttributes.swift` file must be included in both the main app target and the widget extension target. Select the file in Xcode, open the File Inspector, and check both targets under "Target Membership".

**3. Add Info.plist entries in the main app target:**
```xml
<key>NSSupportsLiveActivities</key>
<true/>
```

**4. Register the Live Activity configuration in the widget bundle:**
```swift
@main
struct MyAppWidgets: WidgetBundle {
    var body: some Widget {
        // Existing widgets...
        MyAppLiveActivity()
    }
}
```

**5. Start a Live Activity from your app:**
```swift
let attributes = DeliveryActivityAttributes(
    orderNumber: "1234",
    restaurantName: "Pizza Place"
)

let initialState = DeliveryActivityAttributes.ContentState(
    status: .preparing,
    estimatedDelivery: Date().addingTimeInterval(30 * 60),
    driverName: nil
)

let manager = LiveActivityManager()
try await manager.startActivity(attributes: attributes, state: initialState)
```

**6. Update the activity when state changes:**
```swift
let updatedState = DeliveryActivityAttributes.ContentState(
    status: .enRoute,
    estimatedDelivery: Date().addingTimeInterval(15 * 60),
    driverName: "Alex"
)

await manager.updateActivity(state: updatedState)
```

**7. End the activity when complete:**
```swift
let finalState = DeliveryActivityAttributes.ContentState(
    status: .delivered,
    estimatedDelivery: Date(),
    driverName: "Alex"
)

await manager.endActivity(state: finalState, dismissalPolicy: .default)
```

### Push-to-Update Setup (if enabled)

**1. Observe push tokens:**
The generated `{Name}ActivityManager` automatically observes push token updates. Send the token to your server when it changes.

**2. Server-side APNs request:**
```bash
curl -v \
  --header "authorization: bearer $JWT_TOKEN" \
  --header "apns-topic: com.yourcompany.yourapp.push-type.liveactivity" \
  --header "apns-push-type: liveactivity" \
  --http2 \
  --data '{"aps":{"timestamp":1234567890,"event":"update","content-state":{"status":"enRoute","estimatedDelivery":1234568000,"driverName":"Alex"}}}' \
  https://api.push.apple.com/3/device/$PUSH_TOKEN
```

Note: The `apns-topic` must be your app bundle ID with `.push-type.liveactivity` appended.

**3. Ending via push:**
```json
{
  "aps": {
    "timestamp": 1234567890,
    "event": "end",
    "dismissal-date": 1234568000,
    "content-state": {
      "status": "delivered",
      "estimatedDelivery": 1234567890,
      "driverName": "Alex"
    }
  }
}
```

### Testing Instructions

1. **Device required:** Live Activities and Dynamic Island cannot be tested in Simulator (as of Xcode 15). Use a physical device with iOS 16.1+.
2. **Dynamic Island:** Requires iPhone 14 Pro or later (devices with the Dynamic Island hardware).
3. **Push-to-update testing:** Use a tool like `apnspush` or `curl` with an APNs auth key (.p8 file) to send test payloads.
4. **Debug tips:**
   - Use `Activity<Attributes>.activities` to list all running activities
   - Check Console.app for ActivityKit logs filtered by your app bundle ID
   - Activities are limited to a maximum of 5 concurrent per app

## Common Patterns

### Delivery Tracking
Static: order number, restaurant name
Dynamic: status enum, ETA, driver name

### Sports Score
Static: home team, away team, sport type
Dynamic: home score, away score, period/quarter, game clock

### Workout / Timer
Static: workout type, goal
Dynamic: elapsed time, calories, heart rate, distance

### Ride-Sharing
Static: pickup location, destination
Dynamic: driver name, ETA, vehicle info, status

## Gotchas and Limits

- **Size limit:** `ActivityAttributes` + `ContentState` combined must be under 4KB
- **Concurrent limit:** Maximum 5 active Live Activities per app
- **Duration:** Activities automatically end after 8 hours (can remain on Lock Screen for up to 4 more hours in ended state)
- **Push token changes:** The push token can change during the lifetime of an activity; always observe `pushTokenUpdates`
- **Stale state:** Always set `staleDate` on content to let the system show stale indicators
- **Background updates:** The app can update activities from the background, but not start new ones

## References

- **templates.md** -- Code templates for attributes, widget views, and manager
- [ActivityKit Documentation](https://developer.apple.com/documentation/activitykit)
- [Displaying live data with Live Activities](https://developer.apple.com/documentation/activitykit/displaying-live-data-with-live-activities)
- [Updating and ending your Live Activity with ActivityKit push notifications](https://developer.apple.com/documentation/activitykit/updating-and-ending-your-live-activity-with-activitykit-push-notifications)