const Minio = require('minio');
require('dotenv').config();

/**
 * MinIO 配置
 * 用于对象存储服务配置
 */
const minioConfig = {
  // MinIO 服务器配置
  endPoint: process.env.MINIO_ENDPOINT || 'localhost',
  port: parseInt(process.env.MINIO_PORT) || 9000,
  useSSL: process.env.MINIO_USE_SSL === 'true' || false,
  accessKey: process.env.MINIO_ACCESS_KEY || 'minioadmin',
  secretKey: process.env.MINIO_SECRET_KEY || 'minioadmin',
  
  // 存储桶配置
  buckets: {
    uploads: process.env.MINIO_BUCKET_UPLOADS || 'uploads',
    avatars: process.env.MINIO_BUCKET_AVATARS || 'avatars', 
    products: process.env.MINIO_BUCKET_PRODUCTS || 'products',
    documents: process.env.MINIO_BUCKET_DOCUMENTS || 'documents'
  },
  
  // 文件访问配置
  publicUrl: process.env.MINIO_PUBLIC_URL || `http://localhost:9000`
};

/**
 * 创建 MinIO 客户端实例
 */
const createMinioClient = () => {
  return new Minio.Client({
    endPoint: minioConfig.endPoint,
    port: minioConfig.port,
    useSSL: minioConfig.useSSL,
    accessKey: minioConfig.accessKey,
    secretKey: minioConfig.secretKey
  });
};

/**
 * 初始化存储桶
 * 确保所有需要的存储桶都存在
 */
const initializeBuckets = async () => {
  const minioClient = createMinioClient();
  
  try {
    // 检查并创建存储桶
    for (const [key, bucketName] of Object.entries(minioConfig.buckets)) {
      const exists = await minioClient.bucketExists(bucketName);
      if (!exists) {
        await minioClient.makeBucket(bucketName, 'us-east-1');
        console.log(`✅ 存储桶 '${bucketName}' 创建成功`);
        
        // 设置存储桶策略为公开读取（可选）
        const policy = {
          Version: '2012-10-17',
          Statement: [
            {
              Effect: 'Allow',
              Principal: { AWS: ['*'] },
              Action: ['s3:GetObject'],
              Resource: [`arn:aws:s3:::${bucketName}/*`]
            }
          ]
        };
        
        try {
          await minioClient.setBucketPolicy(bucketName, JSON.stringify(policy));
          console.log(`✅ 存储桶 '${bucketName}' 策略设置成功`);
        } catch (policyError) {
          console.warn(`⚠️  存储桶 '${bucketName}' 策略设置失败:`, policyError.message);
        }
      } else {
        console.log(`✅ 存储桶 '${bucketName}' 已存在`);
      }
    }
  } catch (error) {
    console.error('❌ 初始化存储桶失败:', error);
    throw error;
  }
};

/**
 * 获取文件的公开访问URL
 */
const getPublicUrl = (bucketName, objectName) => {
  return `${minioConfig.publicUrl}/${bucketName}/${objectName}`;
};

module.exports = {
  minioConfig,
  createMinioClient,
  initializeBuckets,
  getPublicUrl
};