# YouTube Processing Workflow - Complete Execution Guide

## 📋 Table of Contents
1. [Overview](#overview)
2. [Prerequisites](#prerequisites)
3. [Installation](#installation)
4. [Configuration](#configuration)
5. [Execution Methods](#execution-methods)
6. [Expected Output](#expected-output)
7. [Troubleshooting](#troubleshooting)
8. [Examples](#examples)

## 🎯 Overview

This is a multi-agent YouTube processing workflow that:
- **Transcribes** YouTube videos using OpenAI Whisper
- **Translates** transcripts to target languages using LLM APIs
- **Summarizes** content based on custom prompts
- **Saves** results to local files in JSON and TXT formats

## 🔧 Prerequisites

### System Requirements
- **Python 3.8+** installed
- **FFmpeg** installed and in system PATH
- **Internet connection** for API calls and video processing

### API Keys Required
- **Perplexity API Key** (primary LLM)
- **OpenAI API Key** (backup LLM)

## 📦 Installation

### 1. Install Python Dependencies
```bash
pip install -r requirements.txt
```

### 2. Install FFmpeg
- **Windows**: Download from [ffmpeg.org](https://ffmpeg.org/download.html) and add to PATH
- **macOS**: `brew install ffmpeg`
- **Ubuntu**: `sudo apt update && sudo apt install ffmpeg`

### 3. Verify Installation
```bash
python -c "import crewai, openai, whisper, yt_dlp; print('All dependencies installed successfully!')"
```

## ⚙️ Configuration

### 1. Create Environment File
Copy the example environment file:
```bash
cp env.example .env
```

### 2. Add API Keys
Edit the `.env` file with your API keys:
```env
# Perplexity API Configuration
PERPLEXITY_API_KEY=your_perplexity_api_key_here

# Optional: OpenAI API Key (as backup LLM)
OPENAI_API_KEY=your_openai_api_key_here
```

### 3. Get API Keys

#### Perplexity API
1. Visit [Perplexity AI](https://perplexity.ai/)
2. Sign up and get your API key
3. Add it to your `.env` file

#### OpenAI API (Backup)
1. Visit [OpenAI Platform](https://platform.openai.com/)
2. Create an API key
3. Add it to your `.env` file

## 🚀 Execution Methods

### Method 1: Simple Example (Recommended for Testing)
```bash
python example.py
```

**What it does:**
- Uses a demo YouTube video (Rick Roll)
- Processes in English
- Creates a 5-bullet point summary
- Saves output to `./output/` directory

### Method 2: Command Line Workflow
```bash
python workflow.py "https://www.youtube.com/watch?v=VIDEO_ID" "English" "Summarize in 5 bullet points for students to revise quickly"
```

**Parameters:**
- `youtube_url`: Full YouTube video URL
- `target_language`: Language for translation (e.g., "English", "Spanish", "French")
- `summarization_prompt`: Custom prompt for summary generation

**Example:**
```bash
python workflow.py "https://www.youtube.com/watch?v=dQw4w9WgXcQ" "Spanish" "Create a 3-point executive summary"
```

### Method 3: REST API Server
```bash
python api.py
```

**Server starts on:** `http://localhost:5000`

**API Endpoints:**
- `POST /process` - Complete video processing
- `POST /transcribe` - Transcription only
- `POST /translate` - Translation only
- `POST /summarize` - Summarization only
- `GET /health` - Health check

### Method 4: Demo with Multiple Examples
```bash
python demo.py
```

### Method 5: Run Tests
```bash
python test.py
```

## 📊 Expected Output

### File Structure
```
output/
├── YYYYMMDD_HHMMSS_VIDEOID_LANGUAGE.json
└── YYYYMMDD_HHMMSS_VIDEOID_LANGUAGE.txt
```

### JSON Output Format
```json
{
  "summary": "Complete summary based on your prompt...",
  "metadata": {
    "youtube_url": "https://www.youtube.com/watch?v=example",
    "target_language": "English",
    "original_transcript_length": 1848,
    "translated_text_length": 1848,
    "workflow_timestamp": "1759118170.3120418",
    "example_run": true,
    "source": "example.py"
  },
  "timestamp": "20250129_143022",
  "type": "youtube_summary",
  "workflow_version": "1.0"
}
```

### TXT Output Format
```
# YouTube Video Summary
**Video:** https://www.youtube.com/watch?v=example
**Language:** English
**Generated:** 20250129_143022

---

Summary based on prompt 'Summarize in 5 bullet points for students to revise quickly':

• Point 1: Key insight or main topic
• Point 2: Important detail or concept
• Point 3: Supporting information
• Point 4: Additional context
• Point 5: Conclusion or takeaway

---

**Metadata:**
{
  "youtube_url": "https://www.youtube.com/watch?v=example",
  "target_language": "English",
  "original_transcript_length": 1848,
  "translated_text_length": 1848,
  "workflow_timestamp": "1759118170.3120418",
  "example_run": true,
  "source": "example.py"
}
```

### Console Output
```
YouTube Processing Workflow - Simple Example
=======================================================

Configuration looks good!

Processing: https://www.youtube.com/watch?v=dQw4w9WgXcQ
Target Language: English
Summary Prompt: Summarize in 5 bullet points for students to revise quickly

Running workflow...
Starting transcription...
Starting translation to English...
Starting summarization...
Starting local file publishing...
Workflow completed!

================================================================================
YOUTUBE PROCESSING WORKFLOW SUMMARY
================================================================================
YouTube URL: https://www.youtube.com/watch?v=dQw4w9WgXcQ
Target Language: English
Summary Prompt: Summarize in 5 bullet points for students to revise quickly
Overall Success: True

STAGE DETAILS:

TRANSCRIPTION:
  Success: True
  Content Preview: Never gonna give you up, never gonna let you down...

TRANSLATION:
  Success: True
  Content Preview: Never gonna give you up, never gonna let you down...

SUMMARIZATION:
  Success: True
  Content Preview: • This is a famous song by Rick Astley
• The song is about commitment and loyalty in relationships...

PUBLISHING:
  Success: True
  Output Files:
    - JSON: ./output/20250129_143022_dQw4w9WgXcQ_English.json
    - TXT: ./output/20250129_143022_dQw4w9WgXcQ_English.txt

================================================================================

Example completed successfully!
```

## 🐛 Troubleshooting

### Common Issues

#### 1. FFmpeg Not Found
```
Error: ffmpeg not found
```
**Solution:** Install FFmpeg and ensure it's in your system PATH.

#### 2. API Key Errors
```
Error: PERPLEXITY_API_KEY not found
```
**Solution:** 
- Check your `.env` file exists
- Verify API keys are correctly formatted
- Ensure no extra spaces or quotes around the keys

#### 3. YouTube Access Issues
```
Error extracting audio from YouTube video
```
**Solution:**
- Ensure the video is public and accessible
- Check if the video has age restrictions
- Verify the URL format is correct

#### 4. Whisper Model Download Issues
```
Error downloading Whisper model
```
**Solution:**
- Check internet connection
- Ensure sufficient disk space (~1GB per model)
- Try running again (models are cached after first download)

#### 5. Import Errors
```
ImportError: No module named 'crewai'
```
**Solution:**
```bash
pip install -r requirements.txt
```

### Debug Mode
Enable debug logging for detailed error information:
```python
import logging
logging.basicConfig(level=logging.DEBUG)
```

## 📝 Examples

### Example 1: Educational Summary
```bash
python workflow.py "https://www.youtube.com/watch?v=example" "English" "Summarize in 5 bullet points for students to revise quickly"
```

### Example 2: Business Summary
```bash
python workflow.py "https://www.youtube.com/watch?v=example" "English" "Create a 3-point executive summary highlighting key business insights"
```

### Example 3: Creative Summary
```bash
python workflow.py "https://www.youtube.com/watch?v=example" "English" "Rewrite as an engaging story with dialogue and vivid descriptions"
```

### Example 4: Multi-language Processing
```bash
# Spanish
python workflow.py "https://www.youtube.com/watch?v=example" "Spanish" "Resumir en 5 puntos clave"

# French
python workflow.py "https://www.youtube.com/watch?v=example" "French" "Résumer en 5 points principaux"

# German
python workflow.py "https://www.youtube.com/watch?v=example" "German" "In 5 Hauptpunkten zusammenfassen"
```

### Example 5: API Usage
```bash
# Start server
python api.py

# Process video via API
curl -X POST http://localhost:5000/process \
  -H "Content-Type: application/json" \
  -d '{
    "youtube_url": "https://www.youtube.com/watch?v=example",
    "target_language": "English",
    "summarization_prompt": "Summarize in 5 bullet points",
    "metadata": {
      "user_id": "student_123",
      "course": "Data Science 101"
    }
  }'
```

## 📈 Performance Tips

1. **Model Selection**: Use smaller Whisper models for faster processing
2. **Batch Processing**: Process multiple videos using the API
3. **Caching**: Models are cached after first download
4. **Async Processing**: Use async/await patterns for large-scale deployments

## 🔍 Supported Languages

The system supports 100+ languages including:
- **European**: English, Spanish, French, German, Italian, Portuguese, Dutch, Swedish, Norwegian, Danish, Finnish
- **Asian**: Chinese, Japanese, Korean, Hindi, Thai, Vietnamese
- **Middle Eastern**: Arabic, Hebrew, Turkish
- **Others**: Russian, Polish, Czech, Hungarian, Romanian

## 📞 Support

For issues and questions:
1. Check the troubleshooting section above
2. Verify all prerequisites are met
3. Check API key configuration
4. Review console output for specific error messages

## 🎉 Success Indicators

Your workflow is working correctly when you see:
- ✅ "Configuration looks good!" message
- ✅ All stages show "Success: True"
- ✅ Output files created in `./output/` directory
- ✅ "Example completed successfully!" message
- ✅ Full summaries (not truncated text)

---

**Last Updated:** January 29, 2025
**Version:** 1.0
**Author:** YouTube Processing Workflow Team