"""FastAPI 应用工厂。"""

from __future__ import annotations

import mimetypes
import sys
from contextlib import asynccontextmanager
from pathlib import Path

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

from fastapi_admin.config import APP_NAME, APP_CORS_ORIGINS
from fastapi_admin.config._loader import _find_project_root
from fastapi_common.fastapi_common_storage.oss_client import OssClient
from fastapi_common.fastapi_common_web.exception.Base.BusinessException import BusinessException

# 确保项目根在 sys.path
_PROJECT_ROOT = _find_project_root()
if str(_PROJECT_ROOT) not in sys.path:
    sys.path.insert(0, str(_PROJECT_ROOT))

# fastapi_modules 目录加入路径（使 importlib 能找到各模块）
_FASTMOD = _PROJECT_ROOT / "fastapi_modules"
_FASTMOD_LEAUDIT = _FASTMOD / "fastapi_leaudit"
_NATIVE_LEAUDIT_SRC = _PROJECT_ROOT.parent / "leaudit" / "src"
if str(_FASTMOD) not in sys.path:
    sys.path.insert(0, str(_FASTMOD))
if str(_FASTMOD_LEAUDIT) not in sys.path:
    sys.path.insert(0, str(_FASTMOD_LEAUDIT))
if _NATIVE_LEAUDIT_SRC.exists() and str(_NATIVE_LEAUDIT_SRC) not in sys.path:
    sys.path.insert(0, str(_NATIVE_LEAUDIT_SRC))


def create_app() -> FastAPI:
    """创建并配置 FastAPI 应用。"""

    @asynccontextmanager
    async def lifespan(app: FastAPI):
        import logging
        logging.basicConfig(level=logging.INFO)
        logging.getLogger("APP").info(f"{APP_NAME} starting...")
        yield
        logging.getLogger("APP").info(f"{APP_NAME} shutting down...")

    app = FastAPI(
        title=APP_NAME,
        version="1.0.0",
        lifespan=lifespan,
        docs_url="/api/docs",
        redoc_url=None,
    )

    # CORS
    origins = [o.strip() for o in APP_CORS_ORIGINS.split(",") if o.strip()]
    app.add_middleware(
        CORSMiddleware,
        allow_origins=origins,
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

    # 统一业务异常处理
    @app.exception_handler(BusinessException)
    async def handle_business_exception(request: Request, exc: BusinessException):
        return JSONResponse(
            status_code=exc.status.value,
            content={
                "code": exc.status.value,
                "message": exc.message,
                "data": None,
            },
        )

    # 注册控制器
    from fastapi_admin.bootstrap_parts.controllers import register_controllers
    register_controllers(app)

    @app.get("/docauditai/{ObjectPath:path}")
    async def GetCompatObject(ObjectPath: str):
        """兼容旧前端的对象访问路径，优先读取新桶对象。"""
        Client = OssClient()
        CandidateBuckets = [Client.bucket, "docauditai"]
        for BucketName in CandidateBuckets:
            try:
                if not Client.ObjectExists(ObjectPath, Bucket=BucketName):
                    continue
                Content = Client.DownloadBytes(ObjectPath, Bucket=BucketName)
                MediaType = mimetypes.guess_type(ObjectPath)[0] or "application/octet-stream"
                return Response(content=Content, media_type=MediaType)
            except Exception:
                continue
        raise HTTPException(status_code=404, detail="Object not found")

    return app


app = create_app()