"""
Chronos-2 Forecasting API - Clean Architecture Version 3.0

Este es el punto de entrada de la aplicación, refactorizado siguiendo
Clean Architecture y principios SOLID.

Características:
- Arquitectura en capas (Presentation, Application, Domain, Infrastructure)
- Dependency Injection completa
- Separación de responsabilidades
- Código mantenible y testeable
"""

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

from app.infrastructure.config.settings import get_settings
from app.utils.logger import setup_logger

# Import routers
from app.api.routes import (
    health_router,
    forecast_router,
    anomaly_router,
    backtest_router
)

logger = setup_logger(__name__)
settings = get_settings()

# ============================================================================
# Create FastAPI App
# ============================================================================

app = FastAPI(
    title=settings.api_title,
    version=settings.api_version,
    description=settings.api_description,
    docs_url="/docs",
    redoc_url="/redoc",
    openapi_url="/openapi.json"
)

# ============================================================================
# Middleware
# ============================================================================

# CORS Middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=settings.cors_origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# ============================================================================
# API Routes
# ============================================================================

# Health check endpoint (temporal, será movido a routes/health.py)
@app.get("/health", tags=["Health"])
async def health_check():
    """Check if the API is running and model is loaded."""
    from app.api.dependencies import get_forecast_model
    
    try:
        model = get_forecast_model()
        model_info = model.get_model_info()
        
        return {
            "status": "ok",
            "version": settings.api_version,
            "model": model_info
        }
    except Exception as e:
        logger.error(f"Health check failed: {e}")
        return {
            "status": "error",
            "version": settings.api_version,
            "error": str(e)
        }


# Include routers
app.include_router(health_router)
app.include_router(forecast_router)
app.include_router(anomaly_router)
app.include_router(backtest_router)

# ============================================================================
# Static Files (Excel Add-in)
# ============================================================================

if os.path.exists(settings.static_dir):
    logger.info(f"Mounting static files from: {settings.static_dir}")
    
    # Mount subdirectories
    for subdir in ["assets", "taskpane", "commands"]:
        path = os.path.join(settings.static_dir, subdir)
        if os.path.exists(path):
            app.mount(f"/{subdir}", StaticFiles(directory=path), name=subdir)
            logger.info(f"Mounted /{subdir}")
    
    # Manifest file
    manifest_path = os.path.join(settings.static_dir, "manifest.xml")
    if os.path.exists(manifest_path):
        @app.get("/manifest.xml")
        async def get_manifest():
            """Serve Excel Add-in manifest."""
            return FileResponse(manifest_path, media_type="application/xml")
        logger.info("Manifest endpoint registered")
else:
    logger.warning(f"Static directory not found: {settings.static_dir}")

# ============================================================================
# Startup/Shutdown Events
# ============================================================================

@app.on_event("startup")
async def startup_event():
    """Initialize resources on startup."""
    logger.info("=" * 60)
    logger.info(f"🚀 {settings.api_title} v{settings.api_version}")
    logger.info("=" * 60)
    logger.info("Architecture: Clean Architecture (4 layers)")
    logger.info("Principles: SOLID")
    logger.info(f"Model: {settings.model_id}")
    logger.info(f"Device: {settings.device_map}")
    logger.info("=" * 60)
    
    # Pre-load model
    try:
        from app.api.dependencies import get_forecast_model
        logger.info("Pre-loading forecast model...")
        model = get_forecast_model()
        logger.info(f"✅ Model loaded: {model.get_model_info()}")
    except Exception as e:
        logger.error(f"❌ Failed to load model: {e}")
        logger.error("API will start but forecasting will fail until model loads")


@app.on_event("shutdown")
async def shutdown_event():
    """Cleanup resources on shutdown."""
    logger.info("=" * 60)
    logger.info("Shutting down Chronos-2 API...")
    logger.info("=" * 60)


# ============================================================================
# Root Endpoint
# ============================================================================

@app.get("/", tags=["Info"])
async def root():
    """API information and documentation links."""
    return {
        "name": settings.api_title,
        "version": settings.api_version,
        "description": settings.api_description,
        "docs": "/docs",
        "health": "/health",
        "architecture": "Clean Architecture with SOLID principles",
        "layers": {
            "presentation": "FastAPI (app/api/)",
            "application": "Use Cases (app/application/)",
            "domain": "Business Logic (app/domain/)",
            "infrastructure": "External Services (app/infrastructure/)"
        }
    }


if __name__ == "__main__":
    import uvicorn
    
    uvicorn.run(
        "app.main_v3:app",
        host="0.0.0.0",
        port=settings.api_port,
        reload=True,
        log_level=settings.log_level.lower()
    )