import os

from app.api.router import api_router, health_router
from app.config import settings
from app.middleware.exceptions import (
    APIException,
    api_exception_handler,
    general_exception_handler,
    http_exception_handler,
    validation_exception_handler,
)
from app.middleware.logging import RequestLoggingMiddleware
from fastapi import FastAPI
from fastapi.exceptions import RequestValidationError
from fastapi.middleware.cors import CORSMiddleware
from fastapi.middleware.gzip import GZipMiddleware
from starlette.exceptions import HTTPException as StarletteHTTPException
from starlette.staticfiles import StaticFiles

app = FastAPI(
    title="小虾 SaaS API",
    description="自动化剪辑 SaaS 平台 API",
    version=settings.APP_VERSION,
    docs_url="/docs",
    redoc_url="/redoc",
)

app.add_exception_handler(APIException, api_exception_handler)
app.add_exception_handler(StarletteHTTPException, http_exception_handler)
app.add_exception_handler(RequestValidationError, validation_exception_handler)
app.add_exception_handler(Exception, general_exception_handler)

# CORS 配置：根据 DEBUG 模式区分
# 生产环境：allow_credentials=True 时不能使用通配符 "*"
if settings.DEBUG:
    # 开发环境：允许所有来源（方便本地调试）
    app.add_middleware(
        CORSMiddleware,
        allow_origins=["*"],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )
else:
    # 生产环境：严格限制来源和方法
    app.add_middleware(
        CORSMiddleware,
        allow_origins=settings.CORS_ORIGINS,
        allow_credentials=True,
        allow_methods=["GET", "POST", "PUT", "DELETE", "PATCH", "OPTIONS"],
        allow_headers=[
            "Authorization",
            "Content-Type",
            "X-Request-ID",
            "X-Correlation-ID",
        ],
    )

app.add_middleware(GZipMiddleware, minimum_size=1000)
app.add_middleware(RequestLoggingMiddleware)

app.include_router(health_router)
app.include_router(api_router)

_generated_files_dir = os.getenv("GENERATED_FILES_DIR", "/app/generated")
os.makedirs(_generated_files_dir, exist_ok=True)
app.mount(
    os.getenv("GENERATED_FILES_URL_PREFIX", "/generated-files"),
    StaticFiles(directory=_generated_files_dir),
    name="generated-files",
)


def create_app() -> FastAPI:
    return app


@app.get("/")
async def root():
    return {
        "service": settings.APP_NAME,
        "status": "running",
        "version": settings.APP_VERSION,
    }


if __name__ == "__main__":
    import uvicorn

    uvicorn.run(app, host=settings.API_HOST, port=settings.API_PORT)