import logging
from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from app.api.router import api_router
from app.config import settings

logger = logging.getLogger("olivas")


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup: ensure DB tables exist
    from app.db.session import engine
    from app.models.base import Base
    # Import all models so Base.metadata knows about them
    import app.models.analysis  # noqa: F401
    import app.models.project  # noqa: F401
    import app.models.aoi  # noqa: F401
    import app.models.comparison  # noqa: F401

    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
    logger.info("Database tables verified")

    # Startup: load ML models
    logger.info(f"Starting OliVAS backend (device={settings.device})")
    from app.services.saliency.model_manager import model_manager

    try:
        model_manager.load_models(device=settings.device)
        logger.info(f"Models loaded: {list(model_manager.models.keys())}")
    except Exception as e:
        logger.warning(f"Failed to load ML models: {e}. Analysis will fail until models load.")

    # Warm up JWKS cache for Azure AD token validation
    if settings.AZURE_AUTH_ENABLED and settings.AZURE_TENANT_ID:
        try:
            from app.auth import refresh_jwks_cache
            refresh_jwks_cache()
            logger.info("Azure AD JWKS cache warmed up")
        except Exception as e:
            logger.warning(f"Failed to warm JWKS cache: {e}. Will fetch on first request.")

    yield

    # Shutdown
    model_manager.cleanup()
    logger.info("OliVAS backend shut down")


app = FastAPI(
    title="OliVAS",
    description="Open-Source Visual Attention Software by OLIVER",
    version="0.1.0",
    lifespan=lifespan,
)

app.add_middleware(
    CORSMiddleware,
    allow_origins=settings.cors_origins_list,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

app.include_router(api_router)