/**
 * MinIO SDK - 上传、下载，随时可调用
 * 复制自 digital 项目
 */

import * as Minio from "minio";
import { getMinioConfig } from "../config";

export interface UploadResult {
  url: string;
  objectKey: string;
}

/** 获取 MinIO 客户端实例 */
export function getMinioClient(overrides?: { bucket?: string; uploadPrefix?: string }): Minio.Client {
  const cfg = getMinioConfig(overrides);
  return new Minio.Client({
    endPoint: cfg.endPoint,
    port: cfg.port,
    useSSL: cfg.useSSL,
    accessKey: cfg.accessKey,
    secretKey: cfg.secretKey,
    pathStyle: true,
    region: cfg.region,
  });
}

/**
 * 上传文件到 MinIO
 * @param buffer 文件内容
 * @param objectKey 对象键（含路径）
 * @param contentType MIME 类型
 */
export async function uploadBuffer(
  buffer: Buffer,
  objectKey: string,
  contentType: string = "application/octet-stream",
  overrides?: { bucket?: string; uploadPrefix?: string }
): Promise<UploadResult> {
  const cfg = getMinioConfig(overrides);
  if (!cfg.enabled) throw new Error("MinIO 存储未启用");

  const client = getMinioClient(overrides);
  await client.putObject(cfg.bucket, objectKey, buffer, buffer.length, {
    "Content-Type": contentType,
  });

  const url = `${cfg.publicUrl}/${objectKey}`;
  return { url, objectKey };
}

/**
 * 生成上传用的对象键
 * @param ext 文件扩展名
 */
export function generateObjectKey(ext: string, overrides?: { uploadPrefix?: string }): string {
  const cfg = getMinioConfig(overrides);
  const prefix = cfg.uploadPrefix.replace(/\/$/, "");
  return `${prefix}/${Date.now()}_${Math.random().toString(36).slice(2)}.${ext}`;
}