# Update Feature Fixes - Final Summary

## Problem Identified
The update feature was causing the application to hang indefinitely when clicked. The issue had two components:

1. **UI Thread Blocking**: The original code was running download operations synchronously on the UI thread
2. **Network Timeout Issues**: Even with timeouts set, the socket-level network calls would hang indefinitely if the server didn't respond

## Solutions Implemented

### 1. Background Threading (First Fix)
- Created `UpdateDownloadWorker` class to run download operations in a background thread
- Moved blocking network calls off the UI thread
- This prevents the UI from freezing while waiting for network operations

### 2. Aggressive Timeout Strategy (Second Fix)
Applied timeouts at multiple levels to ensure the app never hangs:

#### A. Socket-Level Timeout (Most Important)
- **File**: `src/webdrop_bridge/core/updater.py`
- Reduced `urlopen()` timeout from 10 seconds to **5 seconds**
- This is the first line of defense against hanging socket connections
- Applied in `_fetch_release()` method

#### B. Asyncio-Level Timeout
- **File**: `src/webdrop_bridge/ui/main_window.py` and `src/webdrop_bridge/core/updater.py`
- `UpdateCheckWorker`: 10-second timeout on entire check operation
- `UpdateDownloadWorker`: 300-second timeout on download, 30-second on verification
- `check_for_updates()`: 8-second timeout on async executor
- These catch any remaining hangs in the asyncio operations

#### C. Qt-Level Timeout (Final Safety Net)
- **File**: `src/webdrop_bridge/ui/main_window.py`
- Update check: **30-second QTimer** safety timeout (`_run_async_check()`)
- Download: **10-minute QTimer** safety timeout (`_perform_update_async()`)
- If nothing else works, Qt's event loop will forcefully close the operation

### 3. Error Handling Improvements
- Added proper exception handling for `asyncio.TimeoutError`
- Better logging to identify where hangs occur
- User-friendly error messages like "no server response" or "Operation timed out"
- Graceful degradation: operations fail fast instead of hanging

## Timeout Hierarchy (in seconds)
```
Update Check Flow:
  QTimer safety net: 30s ─┐
                          ├─ Asyncio timeout: 10s ─┐
                                                   ├─ Socket timeout: 5s (first to trigger)
Download Flow:
  QTimer safety net: 600s ─┐
                           ├─ Asyncio timeout: 300s ─┐
                                                     ├─ Socket timeout: 5s (first to trigger)
```

## Files Modified
1. **src/webdrop_bridge/ui/main_window.py**
   - Updated `UpdateCheckWorker.run()` with timeout handling
   - Updated `UpdateDownloadWorker.run()` with timeout handling
   - Added QTimer safety timeouts in `_run_async_check()` and `_perform_update_async()`
   - Proper event loop cleanup in finally blocks

2. **src/webdrop_bridge/core/updater.py**
   - Reduced socket timeout in `_fetch_release()` from 10s to 5s
   - Added timeout to `check_for_updates()` async operation
   - Added timeout to `download_update()` async operation
   - Added timeout to `verify_checksum()` async operation
   - Better error logging with exception types

## Testing
- All 7 integration tests pass
- Timeout verification script confirms all timeout mechanisms are in place
- No syntax errors in modified code

## Result
The application will no longer hang indefinitely when checking for or downloading updates. Instead:
- Operations timeout quickly (5-30 seconds depending on operation type)
- User gets clear feedback about what went wrong
- User can retry or cancel without force-killing the app
- Background threads are properly cleaned up to avoid resource leaks