feat(app): implement basic function

General
- 配置界面支持配置对象存储桶
- 快捷键进入截图
- 一键上传截图 & 复制截图链接

MacOS
- 状态栏指示器和应用图标

internal/infrastructure/oss/s3.go

@@ -0,0 +1,124 @@
+// Package oss contains storage adapters that satisfy domain.OSSProvider.
+//
+// The S3 adapter targets any S3-compatible endpoint via aws-sdk-go-v2.
+package oss
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"net/url"
+	"strings"
+
+	awsv2 "github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/credentials"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+
+	"github.com/mmmy/snapgo/internal/domain"
+)
+
+// S3Provider implements domain.OSSProvider using aws-sdk-go-v2.
+//
+// We construct one client per Provider instance because the S3 client is
+// goroutine-safe and the configuration is immutable for the lifetime of the
+// provider.
+type S3Provider struct {
+	cfg    domain.S3Config
+	client *s3.Client
+}
+
+// NewS3Provider builds an *S3Provider from the supplied user configuration.
+//
+// The endpoint is plumbed through BaseEndpoint + UsePathStyle so any
+// S3-compatible service (MinIO, R2, B2, Aliyun OSS s3 endpoint) works
+// without us writing per-vendor branches.
+func NewS3Provider(cfg domain.S3Config) (*S3Provider, error) {
+	if cfg.Endpoint == "" || cfg.Bucket == "" || cfg.AccessKeyID == "" || cfg.SecretAccessKey == "" {
+		return nil, fmt.Errorf("s3 config: endpoint/bucket/accessKeyId/secretAccessKey are required")
+	}
+	region := cfg.Region
+	if region == "" {
+		region = "us-east-1"
+	}
+	awsCfg := awsv2.Config{
+		Region: region,
+		Credentials: credentials.NewStaticCredentialsProvider(
+			cfg.AccessKeyID, cfg.SecretAccessKey, "",
+		),
+	}
+	endpoint := cfg.Endpoint
+	client := s3.NewFromConfig(awsCfg, func(o *s3.Options) {
+		o.BaseEndpoint = awsv2.String(endpoint)
+		o.UsePathStyle = cfg.UsePathStyle
+	})
+	return &S3Provider{cfg: cfg, client: client}, nil
+}
+
+// Name identifies this provider in logs and history records.
+func (p *S3Provider) Name() string { return "s3" }
+
+// Upload pushes the bytes to the configured bucket and returns a public URL.
+//
+// We pass the body via bytes.Reader so the SDK can compute Content-Length
+// and signed checksum without buffering the data twice.
+func (p *S3Provider) Upload(ctx context.Context, key string, data []byte, contentType string) (string, error) {
+	if contentType == "" {
+		contentType = "image/png"
+	}
+	_, err := p.client.PutObject(ctx, &s3.PutObjectInput{
+		Bucket:      awsv2.String(p.cfg.Bucket),
+		Key:         awsv2.String(key),
+		Body:        bytes.NewReader(data),
+		ContentType: awsv2.String(contentType),
+	})
+	if err != nil {
+		return "", fmt.Errorf("s3 put object: %w", err)
+	}
+	return p.BuildPublicURL(key), nil
+}
+
+// BuildPublicURL constructs the URL that the user pastes into Markdown.
+//
+// Priority:
+//  1. PublicURLBase if user filled it (best-fit for CDN-fronted buckets);
+//  2. {Endpoint}/{Bucket}/{Key} for path-style;
+//  3. virtual-hosted-style fallback ({bucket}.host).
+func (p *S3Provider) BuildPublicURL(key string) string {
+	if p.cfg.PublicURLBase != "" {
+		base := strings.TrimRight(p.cfg.PublicURLBase, "/")
+		return base + "/" + key
+	}
+	endpoint := strings.TrimRight(p.cfg.Endpoint, "/")
+	if p.cfg.UsePathStyle {
+		return endpoint + "/" + p.cfg.Bucket + "/" + key
+	}
+	// Virtual-hosted-style: replace host with {bucket}.{host}
+	if u, err := url.Parse(endpoint); err == nil && u.Host != "" {
+		u.Host = p.cfg.Bucket + "." + u.Host
+		u.Path = "/" + key
+		return u.String()
+	}
+	return endpoint + "/" + p.cfg.Bucket + "/" + key
+}
+
+// TestConnection performs a small put + delete to verify credentials and
+// bucket reachability. Used by the "Test connection" button in settings.
+func (p *S3Provider) TestConnection(ctx context.Context) error {
+	probeKey := strings.TrimRight(p.cfg.PathPrefix, "/") + "/.snapgo-probe"
+	probeKey = strings.TrimLeft(probeKey, "/")
+	if _, err := p.client.PutObject(ctx, &s3.PutObjectInput{
+		Bucket:      awsv2.String(p.cfg.Bucket),
+		Key:         awsv2.String(probeKey),
+		Body:        bytes.NewReader([]byte("snapgo")),
+		ContentType: awsv2.String("text/plain"),
+	}); err != nil {
+		return fmt.Errorf("probe put: %w", err)
+	}
+	if _, err := p.client.DeleteObject(ctx, &s3.DeleteObjectInput{
+		Bucket: awsv2.String(p.cfg.Bucket),
+		Key:    awsv2.String(probeKey),
+	}); err != nil {
+		return fmt.Errorf("probe delete: %w", err)
+	}
+	return nil
+}