"""
KYC POC API - Main Application Entry Point

This is a FastAPI application for KYC (Know Your Customer) verification
using face matching (AuraFace) and liveness detection (Silent-Face-Anti-Spoofing).

Run with:
    uvicorn app.main:app --reload --host 0.0.0.0 --port 8000
"""

import logging
from contextlib import asynccontextmanager
from concurrent.futures import ThreadPoolExecutor
import asyncio

from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from fastapi.exceptions import RequestValidationError

from .config import settings
from .api.routes import health, kyc, kyc_base64, ocr
from .services.face_recognition import face_recognition_service
from .services.liveness_detection import liveness_detection_service
from .services.ktp_ocr import ktp_ocr_service

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s - %(name)s - %(levelname)s - %(message)s"
)
logger = logging.getLogger(__name__)

# Thread pool for ML model initialization
executor = ThreadPoolExecutor(max_workers=3)


@asynccontextmanager
async def lifespan(app: FastAPI):
    """
    Application lifespan manager.
    Initializes ML models on startup and cleans up on shutdown.
    """
    logger.info("Starting KYC POC API...")

    # Initialize ML models in background threads
    loop = asyncio.get_event_loop()

    try:
        # Initialize face recognition service
        logger.info("Initializing face recognition service...")
        await loop.run_in_executor(executor, face_recognition_service.initialize)
        logger.info("Face recognition service ready")
    except Exception as e:
        logger.error(f"Failed to initialize face recognition: {e}")

    try:
        # Initialize liveness detection service
        logger.info("Initializing liveness detection service...")
        await loop.run_in_executor(executor, liveness_detection_service.initialize)
        logger.info("Liveness detection service ready")
    except Exception as e:
        logger.error(f"Failed to initialize liveness detection: {e}")

    try:
        # Initialize KTP OCR service
        logger.info("Initializing KTP OCR service...")
        await loop.run_in_executor(executor, ktp_ocr_service.initialize)
        logger.info("KTP OCR service ready")
    except Exception as e:
        logger.error(f"Failed to initialize KTP OCR: {e}")

    logger.info("KYC POC API started successfully")

    yield

    # Cleanup on shutdown
    logger.info("Shutting down KYC POC API...")
    executor.shutdown(wait=True)
    logger.info("Shutdown complete")


# Create FastAPI application
app = FastAPI(
    title=settings.APP_NAME,
    version=settings.APP_VERSION,
    description="""
## KYC POC API

A proof-of-concept API for KYC (Know Your Customer) verification using:
- **AuraFace** for face recognition and matching
- **Silent-Face-Anti-Spoofing** for liveness detection
- **EasyOCR** for KTP text extraction

### Features
- Face matching between KTP (ID card) and selfie
- Liveness detection to prevent spoofing
- Face quality analysis (blur, brightness, pose)
- Age and gender estimation
- **KTP OCR**: Extract and parse Indonesian ID card data (NIK, name, address, etc.)
- **NIK Validation**: Validate and decode NIK information

### Endpoints
- **File Upload**: `/api/v1/kyc/*` - Accepts multipart/form-data
- **Base64**: `/api/v1/kyc/base64/*` - Accepts JSON with base64 images
- **OCR**: `/api/v1/kyc/ocr/*` - KTP text extraction and NIK validation
    """,
    docs_url="/docs",
    redoc_url="/redoc",
    lifespan=lifespan
)

# Add CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


# ============================================================================
# Exception Handlers
# ============================================================================

@app.exception_handler(RequestValidationError)
async def validation_exception_handler(request: Request, exc: RequestValidationError):
    """Handle request validation errors."""
    errors = exc.errors()
    return JSONResponse(
        status_code=422,
        content={
            "error_code": "VALIDATION_ERROR",
            "message": "Request validation failed",
            "detail": errors
        }
    )


@app.exception_handler(Exception)
async def general_exception_handler(request: Request, exc: Exception):
    """Handle unexpected errors."""
    logger.error(f"Unexpected error: {exc}", exc_info=True)
    return JSONResponse(
        status_code=500,
        content={
            "error_code": "INTERNAL_ERROR",
            "message": "An unexpected error occurred",
            "detail": str(exc) if settings.DEBUG else None
        }
    )


# ============================================================================
# Register Routes
# ============================================================================

# Health check routes (no prefix)
app.include_router(health.router)

# KYC routes (file upload)
app.include_router(kyc.router, prefix="/api/v1")

# KYC routes (base64)
app.include_router(kyc_base64.router, prefix="/api/v1")

# OCR routes
app.include_router(ocr.router, prefix="/api/v1")


# ============================================================================
# Main Entry Point
# ============================================================================

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(
        "app.main:app",
        host="0.0.0.0",
        port=8000,
        reload=settings.DEBUG
    )