import sys
import os
import logging
from typing import Optional
from pathlib import Path

# Add the current directory to Python path
current_dir = Path(__file__).parent.absolute()
sys.path.insert(0, str(current_dir))

# Import functional modules
try:
    from main import main, validate_environment
    from audio_utils import validate_environment as validate_audio_env
except ImportError as e:
    print(f"Error importing functional modules: {e}")
    print("Please ensure all required dependencies are installed.")
    sys.exit(1)

# Configure logging
def setup_logging(level: str = "INFO") -> logging.Logger:
    """Set up application logging."""
    log_level = getattr(logging, level.upper(), logging.INFO)
    
    logging.basicConfig(
        level=log_level,
        format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
        handlers=[
            logging.StreamHandler(sys.stdout),
            logging.FileHandler('wisal_app.log', mode='a')
        ]
    )
    
    return logging.getLogger('WisalApp')

def check_dependencies() -> bool:
    """Check if all required dependencies are available."""
    required_packages = [
        'gradio',
        'numpy',
        'soundfile',
        'webrtcvad',
        'fastrtc',
        'google.genai',
        'openai',
        'weaviate',
        'langdetect',
        'requests',
        'langchain',
        'pypdf',
        'docx',  # python-docx imports as 'docx'
        'dotenv'
    ]
    
    missing_packages = []
    
    for package in required_packages:
        try:
            __import__(package.replace('-', '_').replace('.', '.'))
        except ImportError:
            missing_packages.append(package)
    
    if missing_packages:
        print(f"Missing required packages: {', '.join(missing_packages)}")
        print("Please install them using: pip install " + " ".join(missing_packages))
        return False
    
    return True

def check_environment_files() -> bool:
    """Check if required environment files exist."""
    required_files = ['.env']
    missing_files = []
    
    for file_path in required_files:
        if not os.path.exists(file_path):
            missing_files.append(file_path)
    
    if missing_files:
        print(f"Missing required files: {', '.join(missing_files)}")
        print("Please create a .env file with the required API keys.")
        return False
    
    return True

def print_startup_banner():
    """Print application startup banner."""
    banner = """
    ╔═══════════════════════════════════════════════════════════════╗
    ║                                                               ║
    ║              🤖 Wisal: Autism AI Assistant                   ║
    ║                                                               ║
    ║              Functional Programming Version                   ║
    ║              Developed by Compumacy AI                        ║
    ║                                                               ║
    ╚═══════════════════════════════════════════════════════════════╝
    """
    print(banner)

def print_feature_overview():
    """Print overview of available features."""
    features = """
    🔧 Available Features:
    ├── 💬 Text-based chat with autism expertise
    ├── 🎤 Voice input with transcription
    ├── 🔊 Text-to-speech responses
    ├── 📄 Document upload and Q&A
    ├── 🔍 Web search integration
    ├── 🧠 RAG (Retrieval Augmented Generation)
    ├── 🎯 Functional programming architecture
    └── 🌐 Real-time voice chat (WebRTC)
    """
    print(features)

def run_pre_flight_checks() -> bool:
    """Run all pre-flight checks before starting the application."""
    app_logger = setup_logging()
    
    print_startup_banner()
    
    app_logger.info("Starting pre-flight checks...")
    
    # Check 1: Dependencies
    app_logger.info("Checking dependencies...")
    if not check_dependencies():
        app_logger.error("Dependency check failed")
        return False
    app_logger.info("✅ Dependencies check passed")
    
    # Check 2: Environment files
    app_logger.info("Checking environment files...")
    if not check_environment_files():
        app_logger.error("Environment files check failed")
        return False
    app_logger.info("✅ Environment files check passed")
    
    # Check 3: Environment variables
    app_logger.info("Validating environment variables...")
    if not validate_environment():
        app_logger.warning("⚠️  Some environment variables are missing - features may be limited")
    else:
        app_logger.info("✅ Environment variables validated")
    
    # Check 4: Audio environment
    app_logger.info("Checking audio environment...")
    if not validate_audio_env():
        app_logger.warning("⚠️  Audio environment not fully configured - voice features may be limited")
    else:
        app_logger.info("✅ Audio environment validated")
    
    app_logger.info("Pre-flight checks completed")
    print_feature_overview()
    
    return True

def handle_graceful_shutdown():
    """Handle graceful application shutdown."""
    print("\n🔄 Shutting down Wisal gracefully...")
    print("👋 Thank you for using Wisal!")

def run_application():
    """Run the main application with error handling."""
    try:
        print("🚀 Starting Wisal application...")
        main()
    except KeyboardInterrupt:
        handle_graceful_shutdown()
    except Exception as e:
        print(f"❌ Application error: {e}")
        logging.error(f"Application error: {e}", exc_info=True)
        sys.exit(1)

def main_runner():
    """Main runner function."""
    try:
        # Run pre-flight checks
        if not run_pre_flight_checks():
            print("❌ Pre-flight checks failed. Cannot start application.")
            sys.exit(1)
        
        print("✅ All checks passed. Starting application...")
        
        # Run the application
        run_application()
        
    except Exception as e:
        print(f"❌ Fatal error during startup: {e}")
        logging.error(f"Fatal startup error: {e}", exc_info=True)
        sys.exit(1)

if __name__ == "__main__":
    main_runner()