# SlideShow Application - Complete Function Call Flow

## 📋 APPLICATION STARTUP SEQUENCE

```
🚀 HTML LOADS JAVASCRIPT FILES (in order):
slideAppGlobals.js → slideTransitions.js → slideAudio.js → slideUI.js → 
slideFileSelector.js → slideMain.js → slidePlayListLoader.js → slideLoader.js

📡 DOM CONTENT LOADED EVENTS:
├── slideMain.js: Initialize app, wait for JSON selection
├── slideUI.js: Setup UI event listeners  
└── slideFileSelector.js: JsonFileSelector.init()
    ├── setupEventListeners()
    └── discoverDirectories() → Auto-find JSON files
```

## 📁 JSON FILE DISCOVERY FLOW

```
JsonFileSelector.discoverDirectories()
├── generatePotentialDirectories() → ['', 'bk1/', 'template/', ...]
├── checkDirectoryForJsonFiles(dir) → Test each directory
│   └── generateJsonCandidates(dir) → Generate *.json patterns
│       └── generateJsonFilePatterns() → ['slides.json', 'images.json', ...]
└── scanForAllJsonFiles() → Populate file selector
```

## 🎬 SLIDESHOW STARTUP FLOW

```
User selects JSON → JsonFileSelector.startSlideshow()
├── loadSelectedFile() → fetch(file) + detectJsonFileType()
├── Store in SlideApp.slides/playList/images  
├── Hide modal, show slideshow container
└── showSlide(0) → Display first slide
```

## 🖼️ CORE SLIDE DISPLAY

```
showSlide(index) [slideLoader.js]
├── Validate index and slides array
├── Get slide = SlideApp.slides[index]
├── Update DOM: image, title, category, season, audio, etc.
├── Apply transition: slideContainer.className = slide.transition
├── Handle audio: testAudioFile() → tryFallbackAudio()
└── Update status displays
```

## 🎮 USER INTERACTIONS

```
UI Controls [slideUI.js]:
├── Next/Previous → safeShowSlide(newIndex)
├── Play/Pause → playSlides() / pauseSlides()
├── Beginning/End → safeShowSlide(0 or length-1)
└── playSlides() → setInterval() → auto-advance every 5s
```

## 🔧 SAFETY & UTILITIES

```
safeShowSlide(index) → Check function exists → showSlide(index)
SlideApp.safeLog(msg) → Safe console logging
SlideApp.showToast(msg, type) → User notifications
```

## 🔊 AUDIO SYSTEM

```
testAudioFile(file) → Try slide audio → tryFallbackAudio() if fails
Audio Controls: play/pause/mute/volume/timeline
Playlist Management: populate dropdown from SlideApp.playList
```

## 🎯 KEY ENTRY POINTS

1. **App Start**: DOMContentLoaded → JsonFileSelector.init()
2. **File Select**: startSlideshow() → showSlide(0)  
3. **Navigation**: UI events → safeShowSlide()
4. **Auto-play**: playSlides() → interval → safeShowSlide()

## 🔗 DEPENDENCIES

- slideAppGlobals.js (FIRST - contains SlideApp)
- slideFileSelector.js (file discovery)
- slideLoader.js (core display)
- slideUI.js (user controls)
- slideAudio.js (audio system)

## 🎭 FLOW PATTERNS

**Sync**: DOM updates, UI, state changes
**Async**: File loading, JSON parsing, audio
**Events**: User clicks, timers, audio events  
**Safe**: Wrapper functions, validation, error handling