from fastapi import FastAPI, HTTPException, Response
from minio import Minio
from minio.error import S3Error
from pydantic import BaseModel
from datetime import timedelta

app = FastAPI()

# 初始化 MinIO 客户端
minio_client = Minio(
    endpoint="192.168.1.28:9500",  # MinIO 服务器地址
    access_key="UIiBRvUixj3GkJwvItmy",  # Access Key
    secret_key="wgIPqYxaNlDhUds0d3n5v57Yvzg3u9iUXplO7Kdm",  # Secret Key
    secure=False  # 如果没有使用 HTTPS，则设置为 False
)

# MinIO 配置
BUCKET_NAME = "test-bucket"


class FileRequest(BaseModel):
    object_name: str  # 文件对象名
    expiry_in_seconds: int = 3600  # URL 有效期（默认 1 小时）


@app.post("/download-presigned-url")
def generate_presigned_url(file_request: FileRequest):
    """
    生成用于下载文件的预签名 URL
    """
    try:
        # 检查存储桶是否存在
        if not minio_client.bucket_exists(BUCKET_NAME):
            raise HTTPException(status_code=404, detail=f"Bucket '{BUCKET_NAME}' does not exist.")

        # 检查对象是否存在
        try:
            minio_client.stat_object(BUCKET_NAME, file_request.object_name)
        except S3Error:
            raise HTTPException(status_code=404, detail=f"Object '{file_request.object_name}' does not exist.")

        # 将秒数转换为 timedelta
        expiry_timedelta = timedelta(seconds=file_request.expiry_in_seconds)

        # 生成预签名 URL
        presigned_url = minio_client.presigned_get_object(
            BUCKET_NAME,
            file_request.object_name,
            expires=expiry_timedelta  # 传递 timedelta
        )
        return {"presigned_url": presigned_url}

    except S3Error as e:
        raise HTTPException(status_code=500, detail=f"Error generating presigned URL: {e}")
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Unexpected error: {e}")


@app.get("/download-file/{object_name:path}")
def download_file(object_name: str):
    """
    提供文件对象并直接下载
    """
    try:
        print(f"Requested object: {object_name}")

        # 检查存储桶是否存在
        if not minio_client.bucket_exists(BUCKET_NAME):
            raise HTTPException(status_code=404, detail=f"Bucket '{BUCKET_NAME}' does not exist.")

        # 检查对象是否存在
        try:
            stat = minio_client.stat_object(BUCKET_NAME, object_name)
        except S3Error:
            raise HTTPException(status_code=404, detail=f"Object '{object_name}' does not exist.")

        # 获取文件对象
        response = minio_client.get_object(BUCKET_NAME, object_name)

        # 设置响应头
        headers = {
            "Content-Disposition": f"attachment; filename*=UTF-8''{object_name.split('/')[-1]}",
            "Content-Type": stat.content_type
        }
        return Response(content=response.read(), headers=headers, media_type=stat.content_type)

    except S3Error as e:
        raise HTTPException(status_code=500, detail=f"Error downloading file: {e}")
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Unexpected error: {e}")