"""FastAPI 应用入口。

注册中间件、路由、异常处理。
"""

import uuid
from contextlib import asynccontextmanager

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

from app.routers.auth import router as auth_router
from app.routers.companies import router as companies_router
from app.schemas.common import error


@asynccontextmanager
async def lifespan(app: FastAPI):
    """应用生命周期管理。"""
    # startup
    yield
    # shutdown


app = FastAPI(
    title="AIPortPilot",
    description="AI+ Portfolio Operating System — 投后管理与组合协同平台",
    version="0.1.0",
    lifespan=lifespan,
)

# CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["http://localhost:3000"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


@app.middleware("http")
async def trace_id_middleware(request: Request, call_next):
    """为每个请求注入 trace_id。"""
    trace_id = request.headers.get("X-Trace-Id", str(uuid.uuid4()))
    request.state.trace_id = trace_id
    response = await call_next(request)
    response.headers["X-Trace-Id"] = trace_id
    return response


@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    """全局异常处理。"""
    trace_id = getattr(request.state, "trace_id", str(uuid.uuid4()))
    return JSONResponse(
        status_code=500,
        content=error(code=-1, message="内部服务器错误"),
        headers={"X-Trace-Id": trace_id},
    )


@app.get("/health")
async def health_check():
    """健康检查端点。"""
    return {"status": "ok", "service": "aiportpilot-backend", "version": "0.1.0"}


app.include_router(auth_router, prefix="/api/v1")
app.include_router(companies_router, prefix="/api/v1")