# NPC Sound Effects Implementation

**Status:** ✅ Complete (2024-10-31)

## Overview
Added audio feedback to the NPC bark notification system. All bark notifications now play a sound effect when they appear, providing audio cues for player attention.

## Implementation

### Files Modified
- **`js/core/game.js`** (+3 lines)
  - Added `this.load.audio('message_received', ...)` in preload function
  - Loads sound through Phaser's audio system
- **`js/systems/npc-barks.js`** (+65 lines, modified)
  - Replaced HTML5 Audio with Phaser sound manager
  - Added lazy loading fallback
  - Integrated sound playback into `showBark()` method

### Sound Asset Used
- **`assets/sounds/message_received.mp3`**
  - Already existed in project
  - Used for phone message notifications
  - Now also used for NPC bark notifications
  - **Loaded through Phaser's audio system** (Web Audio API)

## Features

### 1. Sound Preloading (Phaser)
```javascript
// In game.js preload()
this.load.audio('message_received', 'assets/sounds/message_received.mp3');

// In npc-barks.js
loadBarkSound() {
  if (window.game && window.game.sound) {
    this.barkSound = window.game.sound.add('message_received');
    this.barkSound.setVolume(0.5); // 50% volume
  }
}
```
- Sound loaded once during Phaser's preload phase
- Managed by Phaser's Web Audio API system
- Automatically pooled for efficient playback
- Default volume: 50%

### 2. Sound Playback (Phaser)
```javascript
playBarkSound() {
  if (!this.soundEnabled) return;
  
  // Lazy load if not available during init
  if (!this.barkSound && window.game && window.game.sound) {
    this.loadBarkSound();
  }
  
  if (!this.barkSound) return;
  
  this.barkSound.play(); // Phaser handles pooling
}
```
- Uses Phaser's `.play()` method (cleaner than HTML5 Audio)
- Phaser automatically handles sound pooling and memory management
- Lazy loading fallback if sound manager not ready during init
- No need to manually reset `currentTime` (Phaser handles this)

### 3. Sound Control
```javascript
setSoundEnabled(enabled) {
  this.soundEnabled = enabled;
}
```
- Allows disabling sounds globally
- Useful for settings/preferences
- Default: enabled

### 4. showBark() Integration
```javascript
showBark(payload = {}) {
  const playSound = payload.playSound !== false; // Default true
  
  if (playSound) {
    this.playBarkSound();
  }
  // ... rest of bark creation
}
```
- Sound enabled by default for all barks
- Can be disabled per-bark via `playSound: false` in payload
- Respects global `soundEnabled` setting

## What Gets Sound?

### ✅ All Bark Notifications
1. **Event-triggered barks**
   - Door unlocks
   - Item pickups
   - Room discoveries
   - Lockpicking attempts
   - CEO office entry
   - Any other event-mapped reactions

2. **Timed messages**
   - Scheduled NPC messages
   - Delivered at specific game times
   - Automatically trigger barks with sound

3. **Manual barks**
   - Any `npcManager.showBark()` calls
   - Any `barkSystem.showBark()` calls

### ❌ No Sound
- Opening phone-chat minigame (no sound yet)
- Closing phone-chat minigame (no sound yet)
- Clicking barks (visual only)
- Choice selections in conversations (visual only)

## Usage Examples

### Default (Sound Enabled)
```javascript
// Sound plays automatically
npcManager.showBark({
  npcId: 'helper_npc',
  npcName: 'Tech Support',
  text: 'Found something interesting!'
});
```

### Disable Sound for Specific Bark
```javascript
// Silent bark (no sound)
npcManager.showBark({
  npcId: 'helper_npc',
  npcName: 'Tech Support',
  text: 'This is a quiet message...',
  playSound: false
});
```

### Disable All Sounds
```javascript
// Turn off bark sounds globally
window.npcManager.barkSystem.setSoundEnabled(false);

// Turn them back on
window.npcManager.barkSystem.setSoundEnabled(true);
```

## Testing

### In-Game Testing
1. Refresh the game page to load updated code
2. Start CEO Exfiltration scenario
3. Test scenarios that trigger barks:
   - Pick up an item → Should hear sound
   - Walk through a door → Should hear sound
   - Unlock a door → Should hear sound
   - Enter CEO office → Should hear sound

### Volume Testing
- Default volume: 50% (0.5)
- Can be adjusted by modifying `this.barkSound.volume` in `loadBarkSound()`
- Recommended range: 0.3 - 0.7 (30% - 70%)

## Browser Compatibility

### Phaser Audio System
- **Chrome/Edge**: ✅ Full Web Audio API support
- **Firefox**: ✅ Full Web Audio API support
- **Safari**: ✅ Full Web Audio API support
- **Mobile browsers**: ✅ Good support (Phaser handles fallbacks)

### Autoplay Policy
Modern browsers restrict autoplay. Phaser handles this automatically:
- ✅ **Works automatically**: Phaser unlocks audio context on first user interaction
- ✅ **No console warnings**: Phaser manages audio context lifecycle
- ✅ **Sounds triggered by user actions**: Always work (clicking, walking)
- ✅ **Better than HTML5 Audio**: Phaser's Web Audio API is more reliable

### Advantages Over HTML5 Audio
1. **Unified audio management**: All game audio through one system
2. **Better performance**: Web Audio API vs Audio Tag
3. **Sound pooling**: Multiple simultaneous sounds without creating new instances
4. **No autoplay issues**: Phaser handles audio context unlocking
5. **Consistent volume control**: Tied to game's master volume
6. **Future-ready**: Can add spatial audio, filters, analyzers, etc.

## Future Enhancements

### Potential Additions
1. **Phone open/close sounds**
   - Add `phone_open.mp3` sound when opening phone-chat
   - Add `phone_close.mp3` sound when closing phone-chat

2. **Choice selection sound**
   - Subtle click sound when selecting dialogue choices
   - Could use existing `GASP_UI_Clicks_*.mp3` sounds

3. **Typing indicator sound**
   - Quiet keyboard sound during typing animation
   - Adds to realism of text messaging

4. **Volume slider in settings**
   - UI control for adjusting bark volume
   - Persist preference to localStorage

5. **Different sounds per NPC type**
   - Helper NPCs: friendly notification sound
   - Adversary NPCs: alert/warning sound
   - Neutral NPCs: standard notification

6. **Sound variations**
   - Randomly pick from multiple notification sounds
   - Prevents repetition fatigue
   - Could use `GASP_UI_Notification_1.mp3` through `_6.mp3`

## Implementation Stats

- **Lines added:** ~68 total
  - `game.js`: +3 lines (audio loading)
  - `npc-barks.js`: +65 lines (Phaser sound integration)
- **Files modified:** 2 (`game.js`, `npc-barks.js`)
- **Breaking changes:** None
- **Default behavior:** Sound enabled
- **Asset used:** Existing (`message_received.mp3`)
- **Audio system:** Phaser Web Audio API (consolidated)

## Next Steps

### Priority 3: NPC Avatars
- Create 3 default 32x32px pixel-art avatars
- Add avatar support to scenarios
- Display avatars in barks and conversations

### Priority 2 Continued: More Events
- Implement `objective_completed` event
- Implement `evidence_collected` event
- Implement `player_detected` event

---
**Status:** ✅ Implementation complete, ready for testing
**Date:** 2024-10-31
