"""PaperGraph 主应用入口 —— FastAPI 实例、中间件、路由挂载与生命周期管理."""

import asyncio
import logging
from contextlib import asynccontextmanager

from fastapi import FastAPI, HTTPException, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from starlette.middleware.base import BaseHTTPMiddleware

from ..settings import configure_logging, get_settings, print_config, validate_config
from ..services.graph.kg_relations import get_kg_metrics
from .routes import paper_routes, paper_reader_routes, search_routes

settings = get_settings()
logger = logging.getLogger(__name__)

class _MeaningfulActivityMiddleware(BaseHTTPMiddleware):

    async def dispatch(self, request: Request, call_next):
        response = await call_next(request)
        try:
            from ..services.daily.daily_auto_refresh import touch_meaningful_activity_if_needed

            touch_meaningful_activity_if_needed(request.app, request.method, request.url.path)
        except Exception:
            pass
        return response

@asynccontextmanager
async def lifespan(app: FastAPI):
    configure_logging(settings.log_level)
    logger.info("%s", "=" * 60)
    logger.info("📚 %s v%s", settings.app_name, settings.app_version)
    logger.info("%s", "=" * 60)

    app.state.last_meaningful_activity_monotonic = None
    daily_refresh_task: asyncio.Task | None = None

    print_config()

    try:
        validate_config()
        logger.info("✅ 配置验证通过")
    except ValueError as e:
        logger.error("❌ 配置验证失败: %s", e)
        raise

    try:
        from ..services.daily.daily_auto_refresh import spawn_daily_auto_refresh

        daily_refresh_task = spawn_daily_auto_refresh(app)
    except Exception as exc:
        logger.warning("每日论文后台自动刷新任务未启动: %s", exc)

    logger.info("%s", "=" * 60)

    yield

    logger.info("%s", "=" * 60)
    logger.info("👋 应用正在关闭...")
    if daily_refresh_task is not None:
        daily_refresh_task.cancel()
        try:
            await daily_refresh_task
        except asyncio.CancelledError:
            pass
        except Exception:
            logger.debug("每日论文后台任务结束异常", exc_info=True)
    logger.info("%s", "=" * 60)

app = FastAPI(
    title=settings.app_name,
    version=settings.app_version,
    description=settings.description,
    docs_url=None,
    redoc_url=None,
    lifespan=lifespan,
)

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

app.add_middleware(_MeaningfulActivityMiddleware)

app.include_router(paper_routes.router, prefix="/api")
app.include_router(paper_reader_routes.router, prefix="/api")
app.include_router(search_routes.router, prefix="/api")

@app.get("/")
async def root():
    return {
        "name": settings.app_name,
        "version": settings.app_version,
        "status": "running",
        "docs_enabled": False,
    }

@app.get("/health")
async def health():
    return {
        "status": "healthy",
        "service": settings.app_name,
        "version": settings.app_version,
        "kg_metrics": get_kg_metrics(),
    }

@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    if isinstance(exc, HTTPException):
        return JSONResponse(status_code=exc.status_code, content={"detail": exc.detail})
    logger.exception(
        "未处理异常: %s %s",
        request.method,
        request.url.path,
        exc_info=exc,
    )
    return JSONResponse(
        status_code=500,
        content={"success": False, "message": str(exc)},
    )

if __name__ == "__main__":
    import uvicorn

    uvicorn.run(
        "app.api.main:app",
        host=settings.host,
        port=settings.port,
        reload=settings.debug,
    )