add subscribe info from origin server

internal/pkg/bytesEx/appender.go

@@ -0,0 +1,16 @@
+package bytesEx
+
+import "bytes"
+
+func AppendPerLine(bytesToAppend []byte, appendContent string) []byte {
+	parts := bytes.Split(bytesToAppend, []byte{'\n'})
+	var buffer bytes.Buffer
+	for i, part := range parts {
+		buffer.Write(part)
+		buffer.WriteString(appendContent)
+		if i < len(parts)-1 {
+			buffer.WriteByte('\n')
+		}
+	}
+	return buffer.Bytes()
+}

internal/pkg/bytesEx/appender_test.go

@@ -0,0 +1,20 @@
+package bytesEx
+
+import (
+	"encoding/base64"
+	"testing"
+)
+
+var data = "xxxx"
+
+func TestAppendPerLine(t *testing.T) {
+	dst := make([]byte, base64.StdEncoding.DecodedLen(len(data)))
+	n, err := base64.StdEncoding.Decode(dst, []byte(data))
+	if err != nil {
+		t.Fatal(err)
+	}
+	dst = dst[:n]
+	line := AppendPerLine(dst, "🤭fucking high")
+	s := base64.StdEncoding.EncodeToString(line)
+	t.Log(s)
+}

internal/pkg/fetcher/fetcher.go

@@ -6,6 +6,7 @@ import (
 	"github.com/go-resty/resty/v2"
 	"net/http"
 	"raycat/internal/pkg/bytesEx"
+	"raycat/internal/pkg/subinfo"
 	"time"
 )
 
@@ -30,16 +31,27 @@ func (c *Client) Fetch(baseUrl string) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
+	var result []byte
 	if !bytesEx.IsBase64(resp.Body()) {
-		return resp.Body(), nil
+		result = resp.Body()
+	} else {
+		decodeLen := base64.StdEncoding.EncodedLen(len(resp.Body()))
+		decoded := make([]byte, decodeLen)
+		n, err := base64.StdEncoding.Decode(decoded, resp.Body())
+		if err != nil {
+			return nil, err
+		}
+		result = decoded[:n]
 	}
-	decodeLen := base64.StdEncoding.EncodedLen(len(resp.Body()))
-	decoded := make([]byte, decodeLen)
-	n, err := base64.StdEncoding.Decode(decoded, resp.Body())
-	if err != nil {
-		return nil, err
+	// check the sub has Subscription-Userinfo
+	subscribeInfo := resp.Header().Get("Subscription-Userinfo")
+	if subscribeInfo != "" {
+		info, err := subinfo.ParseSubscriptionInfo(subscribeInfo)
+		if err == nil && info != nil {
+			result = bytesEx.AppendPerLine(result, info.String())
+		}
 	}
-	return decoded[:n], nil
+	return result, nil
 }
 
 func checkResourceAvailable(url string) bool {

internal/pkg/subinfo/subinfo.go

@@ -0,0 +1,80 @@
+package subinfo
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	units = "KMGTPE"
+	unit  = 1024
+)
+
+var (
+	invalidSubscribeUserInfoError = errors.New("invalid subscribe user info ")
+)
+
+// SubscriptionInfo 结构体用于存储解析后的信息
+type SubscriptionInfo struct {
+	Upload   int64
+	Download int64
+	Total    int64
+	Expire   time.Time
+}
+
+// ParseSubscriptionInfo parse Subscription-Userinfo
+func ParseSubscriptionInfo(info string) (*SubscriptionInfo, error) {
+	result := &SubscriptionInfo{}
+	pairs := strings.Split(info, ";")
+	if len(pairs) == 0 {
+		return nil, invalidSubscribeUserInfoError
+	}
+	for _, pair := range pairs {
+		pair = strings.TrimSpace(pair)
+		kv := strings.SplitN(pair, "=", 2)
+		if len(kv) != 2 {
+			continue
+		}
+		key := strings.TrimSpace(kv[0])
+		value := strings.TrimSpace(kv[1])
+
+		switch key {
+		case "upload":
+			result.Upload, _ = strconv.ParseInt(value, 10, 64)
+		case "download":
+			result.Download, _ = strconv.ParseInt(value, 10, 64)
+		case "total":
+			result.Total, _ = strconv.ParseInt(value, 10, 64)
+		case "expire":
+			expireTime, err := strconv.ParseInt(value, 10, 64)
+			if err == nil {
+				result.Expire = time.Unix(expireTime, 0)
+			}
+		}
+	}
+	return result, nil
+}
+
+func formatBytes(bytes int64) string {
+	if bytes < unit {
+		return fmt.Sprintf("%d B", bytes)
+	}
+	div, exp := int64(unit), 0
+	for n := bytes / unit; n >= unit; n /= unit {
+		div *= unit
+		exp++
+	}
+	return fmt.Sprintf("%.1f %cB", float64(bytes)/float64(div), units[exp])
+}
+
+// String impl Stringer to display
+func (si *SubscriptionInfo) String() string {
+	return fmt.Sprintf("ℹ Upload: %s Download: %s Total: %s ExpireAt: %s",
+		formatBytes(si.Upload),
+		formatBytes(si.Download),
+		formatBytes(si.Total),
+		si.Expire.Format("2006-01-02 15:04"))
+}