app/main.py

"""VoiceGuard API - Main Application Entry Point.

AI-Generated Voice Detection API for Indian Languages.
Supports: Tamil, English, Hindi, Malayalam, Telugu
"""

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles
import os

from app.api.routes import router
from app.config import settings
from app.core.detector import detector


# Create FastAPI app
app = FastAPI(
    title="VoiceGuard API",
    description="""
    ## AI-Generated Voice Detection for Indian Languages
    
    VoiceGuard detects whether an audio sample is AI-generated (deepfake) or genuine human speech.
    
    ### Features
    ### Features
    - 🎯 **Multi-Language Support**: Tamil, English, Hindi, Malayalam, Telugu
    - 📝 **Explanations**: Human-readable reasoning for each detection
    
    ### How It Works
    1. Upload Base64-encoded MP3/WAV audio
    2. AI analyzes the audio for synthetic patterns
    3. Get classification, confidence, and visual explanation
    
    ---
    
    **India AI Impact Summit Buildathon 2026**
    """,
    version="1.0.0",
    docs_url="/docs",
    redoc_url="/redoc"
)

# Add CORS middleware (allow frontend to connect)
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allow all origins for demo
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Mount frontend files
frontend_dir = os.path.join(os.path.dirname(os.path.dirname(__file__)), "frontend")
if os.path.exists(frontend_dir):
    app.mount("/frontend", StaticFiles(directory=frontend_dir, html=True), name="frontend")

# Include API routes (endpoint: /api/voice-detection)
app.include_router(router, prefix="/api", tags=["Detection"])


# ============== ROOT ENDPOINT ==============

@app.get("/", tags=["Info"])
async def root():
    """Root endpoint with API information."""
    return {
        "name": "VoiceGuard API",
        "description": "AI-Generated Voice Detection for Indian Languages",
        "version": "1.0.0",
        "docs": "/docs",
        "frontend": "/frontend/",
        "health": "/api/health",
        "languages": ["tamil", "english", "hindi", "malayalam", "telugu"],
        "status": "online"
    }


@app.get("/favicon.ico", include_in_schema=False)
async def favicon():
    """Return empty response for favicon (browser default request)."""
    from fastapi.responses import Response
    return Response(content="", media_type="image/x-icon")


# ============== STARTUP EVENT ==============

@app.on_event("startup")
async def startup_event():
    """Initialize resources on startup."""
    print("=" * 50)
    print("🛡️  VoiceGuard API Starting...")
    print("=" * 50)
    
    # Single multilingual model for all languages
    print("📌 Single-model architecture:")
    print("   Model: abhishtagatya/hubert-base-960h-itw-deepfake")
    print("   Accuracy: Human=99.83%, AI=99.79%")
    print("   Languages: Tamil, English, Hindi, Malayalam, Telugu")
    
    print("=" * 50)
    print(f"🚀 API ready at http://{settings.HOST}:{settings.PORT}")
    print(f"📚 Docs: http://{settings.HOST}:{settings.PORT}/docs")
    print(f"🎨 Frontend: http://{settings.HOST}:{settings.PORT}/frontend/")
    print("=" * 50)


# ============== SHUTDOWN EVENT ==============

@app.on_event("shutdown")
async def shutdown_event():
    """Cleanup on shutdown."""
    print("VoiceGuard API shutting down...")


# ============== MAIN ==============

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(
        "app.main:app",
        host=settings.HOST,
        port=settings.PORT,
        reload=settings.DEBUG
    )