"""
CrownCode backend entrypoint with enhanced error handling.
"""

from __future__ import annotations

import asyncio
import os
from contextlib import asynccontextmanager

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

from .routes.health import router as health_router
from .routes.youtube import router as youtube_router
from .routes.data_processing import router as data_processing_router
from .routes.analyze import router as analyze_router
from .routes.commend import router as commend_router
from .routes.reservations import router as reservations_router
from .routes.dreams import router as dreams_router
from .routes.remix import router as remix_router
from .services.logging_config import setup_logging, get_logger


setup_logging(level=os.getenv("LOG_LEVEL", "INFO"))
logger = get_logger(__name__)


def _load_origins() -> list[str]:
    raw = os.getenv("CROWNCODE_CORS_ORIGINS") or os.getenv("CORS_ORIGIN") or "http://localhost:3000"
    if raw.strip() == "*":
        logger.warning(
            "CORS wildcard '*' is not recommended for production. "
            "Set CROWNCODE_CORS_ORIGINS to an explicit origin list."
        )
        return ["*"]
    origins = [origin.strip() for origin in raw.split(",") if origin.strip()]
    if not origins:
        # No origins configured — default to localhost for development
        origins = ["http://localhost:3000"]
        logger.warning("No CORS origins configured, defaulting to localhost")
    logger.info(f"CORS configured for origins: {origins}")
    return origins


@asynccontextmanager
async def lifespan(_app: FastAPI):
    # On the Space (AURIS_WARMUP=1 in the Dockerfile) load the models and
    # compile librosa's numba code before the first visitor; off in tests.
    warm_task = None
    if os.getenv("AURIS_WARMUP") == "1":
        from .routes.analyze import warm_up
        warm_task = asyncio.create_task(warm_up())
    yield
    if warm_task is not None and not warm_task.done():
        warm_task.cancel()


app = FastAPI(title="CrownCode Backend API", version="0.1.0", lifespan=lifespan)


@app.get("/")
async def root():
    """Root endpoint for health check and API info."""
    return {
        "name": "CrownCode Backend API",
        "version": "0.1.0",
        "status": "running",
        "docs": "/docs",
        "health": "/api/health"
    }


@app.exception_handler(ValueError)
async def value_error_handler(request: Request, exc: ValueError) -> JSONResponse:
    logger.warning(f"Validation error: {exc}")
    return JSONResponse(
        status_code=400,
        content={"detail": str(exc), "type": "validation_error"}
    )


@app.exception_handler(FileNotFoundError)
async def file_not_found_handler(request: Request, exc: FileNotFoundError) -> JSONResponse:
    logger.error(f"File not found: {exc}")
    return JSONResponse(
        status_code=404,
        content={"detail": "Resource not found", "type": "not_found"}
    )


@app.exception_handler(Exception)
async def general_exception_handler(request: Request, exc: Exception) -> JSONResponse:
    logger.error(f"Unhandled exception: {type(exc).__name__}: {exc}", exc_info=True)
    return JSONResponse(
        status_code=500,
        content={"detail": "Internal server error", "type": "server_error"}
    )


_origins = _load_origins()
app.add_middleware(
    CORSMiddleware,
    allow_origins=_origins,
    allow_credentials="*" not in _origins,
    allow_methods=["GET", "POST", "DELETE", "OPTIONS"],
    allow_headers=["Content-Type", "Accept"],
    expose_headers=["X-Remix-Analysis", "X-Multitrack-Analysis"],
)

app.include_router(health_router)
app.include_router(youtube_router)
app.include_router(data_processing_router)
app.include_router(analyze_router)
app.include_router(commend_router)
app.include_router(reservations_router)
app.include_router(dreams_router)
app.include_router(remix_router)

logger.info("CrownCode backend API initialized")