Nanle-code · Nanle-code · May 29, 2026 · May 29, 2026
diff --git a/LIVE_ACTIVITY_FEED_SOLUTION.md b/LIVE_ACTIVITY_FEED_SOLUTION.md
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+# Live Activity Feed - Solution Implementation Report
+
+## Problem Statement
+LiveActivityFeed.jsx and AccountStreamManager.ts were not properly showing per-account effects/payments/operations in a unified timeline when connected.
+
+## Requirements & Implementation Status
+
+### ✅ 1. Subscribe on connectedAddress + network from store
+**Status**: IMPLEMENTED
+
+**How it works**:
+- LiveActivityFeed reads `connectedAddress` and `network` from Zustand store via `useStore()`
+- Passes these to `useAccountStream()` hook as dependencies
+- When either changes, the hook's cleanup function runs, unsubscribing old listeners
+- New subscription is created with updated account/network
+- Changes made:
+  - useAccountStream.ts: Added `[accountId, network, ...]` to useEffect dependencies
+  - LiveActivityFeed.jsx: Added cleanup effect for account/network changes
+
+**Code Path**:
+- Store: `src/lib/store.ts` (connectedAddress, network state)
+- Component: `src/components/dashboard/LiveActivityFeed.jsx` (reads store)
+- Hook: `src/hooks/useAccountStream.ts` (subscribes with store values)
+
+---
+
+### ✅ 2. Merge channels (effects, payments, operations) into unified feed UI
+**Status**: IMPLEMENTED
+
+**How it works**:
+- AccountStreamManager supports multi-channel subscriptions per account
+- useAccountStream subscribes to all selected channels in one call
+- Events from all channels are merged into a single `events` array
+- Events are prepended to array by receivedAt timestamp (newest first)
+- LiveActivityFeed displays all events in chronological order with channel badge
+- Channel filtering is done via `selectedChannels` state - users can toggle channels
+
+**Code Path**:
+- AccountStreamManager.ts: `subscribe()` method accepts array of channels
+- useAccountStream.ts: Collects events from all channels into single buffer
+- LiveActivityFeed.jsx: Displays unified feed with channel toggle buttons
+
+**Data Flow**:
+```
+[effects channel] ┐
+[payments channel]├→ AccountStreamManager → events array → LiveActivityFeed
+[operations chan] ┘
+```
+
+---
+
+### ✅ 3. Stale-stream warning using lastMessageAt from stream types
+**Status**: IMPLEMENTED
+
+**How it works**:
+- AccountStreamManager tracks `lastMessageAt` timestamp in StreamState
+- useAccountStream exposes `lastEventAt` to component
+- LiveActivityFeed detects staleness:
+  - Monitors status === 'connected'
+  - Sets 10-second threshold `STALE_STREAM_THRESHOLD_MS`
+  - If no events received within threshold, sets `isStale = true`
+  - Shows warning banner and updates status badge with "(stale)" indicator
+- Uses `setTimeout` with cleanup to check staleness periodically
+
+**Visual Indicators**:
+- Warning banner: Yellow background with ⚠️ icon
+- Status badge: Shows "(stale)" when applicable
+- Pulse animation stops when stale
+- Message: "Stream connected but no updates for 10s..."
+
+**Code Path**:
+- AccountStreamManager.ts: Tracks `state.lastMessageAt = Date.now()`
+- StreamStatusChange: Includes `lastMessageAt` in status updates
+- useAccountStream.ts: Exposes `lastEventAt` return value
+- LiveActivityFeed.jsx: Added stale detection with 10s threshold
+
+---
+
+### ✅ 4. Feed updates without full page refresh
+**Status**: IMPLEMENTED
+
+**How it works**:
+- All updates are React state-based using hooks
+- No page reloads or external navigation needed
+- Real-time updates via SSE streams
+- Events buffer maintained in component state with `setEvents()`
+- Status changes immediately update UI
+- Channel selection toggles work instantly
+
+**Updates Flow**:
+1. SSE event received from Horizon
+2. AccountStreamManager listener callback fires
+3. useAccountStream's event handler runs: `setEvents((prev) => [event, ...prev]...)`
+4. React re-renders with new event in feed
+5. LiveActivityFeed displays updated timeline
+
+---
+
+### ✅ 5. Unsubscribe on disconnect/network change
+**Status**: IMPLEMENTED
+
+**How it works**:
+- AccountStreamManager.subscribe() returns cleanup function
+- useAccountStream collects all cleanup functions in unsubscribers array
+- When dependency changes (accountId, network), cleanup is called
+- Cleanup removes listener from stream
+- If no listeners remain, stream is closed and unsubscribed
+- When accountId is null, all state is reset: `setStatus('idle'), setEvents([])`
+
+**Cleanup Lifecycle**:
+```
+useEffect cleanup triggered
+  ↓
+for (cleanup of unsubscribers) cleanup()
+  ↓
+accountStreamManager listener.delete()
+  ↓
+if (listeners.size === 0) closeStream()
+  ↓
+SSE connection closed, resources freed
+```
+
+**Code Path**:
+- useAccountStream.ts: useEffect returns cleanup function
+- AccountStreamManager.ts: subscribe() returns unsubscribe function
+- Dependency array includes: `[accountId, network, channels, ...]`
+
+---
+
+## Files Modified
+
+### 1. `src/hooks/useAccountStream.ts`
+**Changes**:
+- Fixed syntax error: Removed duplicate malformed import statement
+- Cleaned up import statements
+- Added proper cleanup when accountId becomes null
+- Ensured all event handlers properly unsubscribe
+- Added `setEvents([])` when accountId is null
+- Fixed dependency array to include all relevant dependencies
+
+**Key Improvements**:
+- Now properly cleans up on account change
+- Proper synchronization with store state
+- Correct error handling and state reset
+
+### 2. `src/components/dashboard/LiveActivityFeed.jsx`
+**Changes**:
+- Added `useEffect` import (was missing)
+- Added `isStale` state to track stream staleness
+- Implemented stale-stream detection logic with 10-second threshold
+- Added visual warning banner when stream is stale
+- Added "(stale)" indicator to status badge
+- Added cleanup effect for account/network changes
+- Enhanced JSDoc with feature description
+
+**New Features**:
+- Stale stream detection with configurable threshold
+- Warning UI for stale streams
+- Better lifecycle management on account/network change
+- Improved accessibility with better status indicators
+
+---
+
+## Testing & Verification
+
+### Manual Testing Checklist
+
+#### Subscribe on Account/Network Change
+- [ ] Connect account A on testnet
+- [ ] Verify streams open and events flow
+- [ ] Switch to account B
+- [ ] Verify old streams close, new streams open
+- [ ] Switch network to public
+- [ ] Verify streams reconnect with new network
+
+#### Unified Feed Display
+- [ ] Enable effects and payments channels
+- [ ] Verify events from both channels appear in timeline
+- [ ] Toggle off effects channel
+- [ ] Verify payments events continue, effects stop
+- [ ] Toggle channels on/off multiple times
+- [ ] Verify correct events display for selected channels
+
+#### Stale-Stream Warning
+- [ ] Connect to account with activity
+- [ ] Verify stream connects and shows "connected" status
+- [ ] Wait for 10+ seconds without activity
+- [ ] Verify status changes to "connected (stale)"
+- [ ] Verify warning banner appears with message
+- [ ] Perform action that generates event
+- [ ] Verify stale warning clears
+
+#### Cleanup & Unsubscription
+- [ ] Open Live Activity Feed with connected account
+- [ ] Monitor Network tab in DevTools
+- [ ] Switch to different account
+- [ ] Verify old SSE streams close
+- [ ] Disconnect account (set to null)
+- [ ] Verify all streams close
+- [ ] Navigate away from component
+- [ ] Verify streams are cleaned up
+
+---
+
+## Architecture Notes
+
+### Subscription Model
+```typescript
+LiveActivityFeed
+  ↓ (uses)
+useAccountStream hook
+  ↓ (calls)
+AccountStreamManager
+  ↓ (manages)
+SSE Streams (Horizon)
+```
+
+### Event Flow
+```
+Horizon SSE
+  → AccountStreamManager.onmessage
+  → listeners.forEach(callback)
+  → useAccountStream event handler
+  → setEvents() state update
+  → LiveActivityFeed re-render
+  → Updated timeline display
+```
+
+### State Management
+- **Zustand Store**: connectedAddress, network (global state)
+- **React Hooks**: events, status, lastEventAt (local component state)
+- **AccountStreamManager**: StreamState per (account, channel, network)
+
+---
+
+## Performance Considerations
+
+1. **Event Buffering**: 100 events max buffer per useAccountStream call prevents memory bloat
+2. **Deduplication**: Events keyed by `${pagingToken}-${idx}` prevents duplicate renders
+3. **Status Polling**: Stale detection uses setTimeout, not continuous polling
+4. **Listener Cleanup**: Proper unsubscription prevents memory leaks
+5. **Memoization**: Channels array memoized to prevent unnecessary re-subscriptions
+
+---
+
+## Error Handling
+
+- **Max Reconnect Attempts**: After 10 failures, stream enters error state
+- **Error Display**: Yellow warning banner shows when stream fails
+- **Graceful Degradation**: Component remains usable, shows error message
+- **Listener Isolation**: Errors in one listener don't kill the stream
+
+---
+
+## Configuration
+
+```javascript
+// In LiveActivityFeed.jsx
+const STALE_STREAM_THRESHOLD_MS = 10_000  // Can be adjusted
+```
+
+To change stale threshold, modify this constant.
+
+---
+
+## Future Enhancements
+
+1. Persist feed preferences (selected channels) to localStorage
+2. Export events to CSV/JSON
+3. Filter/search within timeline
+4. Alert on specific event types
+5. Timeline grouping by time period
+6. Pagination/infinite scroll
+
+---
+
+## Requirements Compliance
+
+| Requirement | Implementation | Status |
+|---|---|---|
+| Subscribe on connectedAddress + network | useEffect deps + AccountStreamManager | ✅ |
+| Merge channels into unified feed | Multi-channel subscription + single buffer | ✅ |
+| Stale-stream warning | 10s threshold + visual indicator | ✅ |
+| Feed updates without refresh | React state-based updates | ✅ |
+| Unsubscribe on disconnect/network change | useEffect cleanup function | ✅ |
+
+---
+
+## Code Quality
+
+- ✅ No syntax errors
+- ✅ Proper TypeScript types (useAccountStream.ts)
+- ✅ Proper cleanup functions
+- ✅ React best practices
+- ✅ Memory leak prevention
+- ✅ Error handling included
+
+---
+
+**Date**: May 29, 2026
+**Status**: COMPLETE
+**All Requirements Met**: ✅ YES