from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from starlette.middleware.base import BaseHTTPMiddleware

from app.api.main import api_router
from app.api.v1 import websocket
from app.core.config import settings
from app.core.websocket.broadcaster import broadcaster
from app.db.session import init_db
from app.services.scheduler import (
    cleanup_stale_running_tasks,
    start_scheduler,
    stop_scheduler,
    sync_scheduler_with_datasources,
)


class WebSocketCORSMiddleware(BaseHTTPMiddleware):
    async def dispatch(self, request, call_next):
        if request.url.path.startswith("/ws") and request.method == "GET":
            response = await call_next(request)
            response.headers["Access-Control-Allow-Origin"] = "*"
            response.headers["Access-Control-Allow-Methods"] = "GET, OPTIONS"
            response.headers["Access-Control-Allow-Headers"] = "*"
            return response
        return await call_next(request)


@asynccontextmanager
async def lifespan(app: FastAPI):
    await init_db()
    await cleanup_stale_running_tasks()
    start_scheduler()
    await sync_scheduler_with_datasources()
    broadcaster.start()
    yield
    broadcaster.stop()
    stop_scheduler()


app = FastAPI(
    title=settings.PROJECT_NAME,
    version=settings.VERSION,
    description="智能星球计划 - 态势感知系统\n\n## 功能模块\n\n- **用户认证**: JWT-based authentication\n- **数据源管理**: 多源数据采集器管理\n- **任务调度**: 定时任务调度与监控\n- **实时更新**: WebSocket实时数据推送\n- **告警系统**: 多级告警管理\n\n## 数据层级\n\n- **L1**: 核心数据 (TOP500, Epoch AI GPU)\n- **L2**: 扩展数据 (HuggingFace, PeeringDB, 海缆)\n- **L3**: 分析数据\n- **L4**: 决策支持",
    lifespan=lifespan,
    docs_url=None,
    redoc_url="/docs",
    openapi_url="/openapi.json",
)

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

app.add_middleware(WebSocketCORSMiddleware)

app.include_router(api_router, prefix="/api/v1")
app.include_router(websocket.router)


@app.get("/health")
async def health_check():
    return {"status": "healthy", "version": settings.VERSION}


@app.get("/")
async def root():
    return {
        "name": settings.PROJECT_NAME,
        "version": settings.VERSION,
        "docs": "/docs",
        "redoc": "/redoc",
    }


@app.get("/api/v1/scheduler/jobs")
async def get_scheduler_jobs():
    from app.services.scheduler import get_scheduler_jobs

    return {"jobs": get_scheduler_jobs()}