backend/internal/pkg/s3/s3.go

package s3

import (
	"bytes"
	"context"
	"fmt"
	"time"

	"github.com/minio/minio-go/v7"
	"github.com/minio/minio-go/v7/pkg/credentials"

	"with_you/internal/config"
)

// Client S3客户端
type Client struct {
	client *minio.Client
	bucket string
	domain string
}

// New 创建S3客户端
func New(cfg *config.S3Config) (*Client, error) {
	ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
	defer cancel()

	client, err := minio.New(cfg.Endpoint, &minio.Options{
		Creds:  credentials.NewStaticV4(cfg.AccessKey, cfg.SecretKey, ""),
		Secure: cfg.UseSSL,
	})
	if err != nil {
		return nil, fmt.Errorf("failed to create S3 client: %w", err)
	}

	// 检查bucket是否存在，权限不足时跳过检查（不阻塞启动）
	exists, err := client.BucketExists(ctx, cfg.Bucket)
	if err != nil {
		// Access Denied 或网络不通时，跳过 bucket 检查，假定 bucket 已存在
		// 后续上传时会暴露具体错误
	} else if !exists {
		if err := client.MakeBucket(ctx, cfg.Bucket, minio.MakeBucketOptions{
			Region: cfg.Region,
		}); err != nil {
			return nil, fmt.Errorf("failed to create bucket: %w", err)
		}
	}

	// 如果没有配置domain，则使用默认的endpoint
	domain := cfg.Domain
	if domain == "" {
		domain = cfg.Endpoint
	}

	return &Client{
		client: client,
		bucket: cfg.Bucket,
		domain: domain,
	}, nil
}

// Upload 上传文件
func (c *Client) Upload(ctx context.Context, objectName string, filePath string, contentType string) (string, error) {
	_, err := c.client.FPutObject(ctx, c.bucket, objectName, filePath, minio.PutObjectOptions{
		ContentType: contentType,
	})
	if err != nil {
		return "", fmt.Errorf("failed to upload file: %w", err)
	}

	return fmt.Sprintf("%s/%s", c.bucket, objectName), nil
}

// UploadData 上传数据
func (c *Client) UploadData(ctx context.Context, objectName string, data []byte, contentType string) (string, error) {
	_, err := c.client.PutObject(ctx, c.bucket, objectName, bytes.NewReader(data), int64(len(data)), minio.PutObjectOptions{
		ContentType: contentType,
	})
	if err != nil {
		return "", fmt.Errorf("failed to upload data: %w", err)
	}

	// 返回完整URL，包含bucket名称
	scheme := "https"
	if c.domain == c.bucket || c.domain == "" {
		scheme = "http"
	}
	return fmt.Sprintf("%s://%s/%s/%s", scheme, c.domain, c.bucket, objectName), nil
}

// TrustedPublicURLPrefix 本站公开对象 URL 前缀（scheme://domain/bucket/），用于校验聊天图片等仅引用本地上传资源。
func (c *Client) TrustedPublicURLPrefix() string {
	if c == nil || c.domain == "" || c.bucket == "" {
		return ""
	}
	scheme := "https"
	if c.domain == c.bucket {
		scheme = "http"
	}
	return fmt.Sprintf("%s://%s/%s/", scheme, c.domain, c.bucket)
}

// GetURL 获取文件URL - 使用自定义域名
func (c *Client) GetURL(ctx context.Context, objectName string) (string, error) {
	// 使用自定义域名构建URL，包含bucket名称
	scheme := "https"
	if c.domain == c.bucket || c.domain == "" {
		scheme = "http"
	}
	return fmt.Sprintf("%s://%s/%s/%s", scheme, c.domain, c.bucket, objectName), nil
}

// GetPresignedURL 获取预签名URL（用于私有桶）
func (c *Client) GetPresignedURL(ctx context.Context, objectName string) (string, error) {
	url, err := c.client.PresignedGetObject(ctx, c.bucket, objectName, time.Hour*24, nil)
	if err != nil {
		return "", fmt.Errorf("failed to get presigned URL: %w", err)
	}

	return url.String(), nil
}

// Delete 删除文件
func (c *Client) Delete(ctx context.Context, objectName string) error {
	return c.client.RemoveObject(ctx, c.bucket, objectName, minio.RemoveObjectOptions{})
}

// GetClient 获取原生客户端
func (c *Client) GetClient() *minio.Client {
	return c.client
}