From 9b2d71246932497f104f2ac09cab80dce06745b5 Mon Sep 17 00:00:00 2001
From: Vincent Young <missuo@pm.me>
Date: Tue, 28 Nov 2023 00:24:41 -0500
Subject: [PATCH] feat: support multiple authkeys

---
 README.md |  4 +--
 main.go   | 77 +++++++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 63 insertions(+), 18 deletions(-)

diff --git a/README.md b/README.md
index 570ee30d..511268a8 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
  * @Author: Vincent Young
  * @Date: 2022-10-18 07:32:29
  * @LastEditors: Vincent Young
- * @LastEditTime: 2023-11-27 15:06:22
+ * @LastEditTime: 2023-11-28 00:24:20
  * @FilePath: /DeepLX/README.md
  * @Telegram: https://t.me/missuo
  * 
@@ -67,7 +67,7 @@
 **The following settings are optional and not required.**
 - `-port` or `-p` : Listening port. Default is `1188`.
 - `-token` : Access token. If you have set it up, each request will need to include an `Authorization` header.
-- `-authkey` : DeepL Official `AuthKey`. If you have set it up, after the 429 response, the official AuthKey will be used for the request.
+- `-authkey` : DeepL Official `AuthKey`. If you have set it up, after the 429 response, the official AuthKey will be used for the request. If multiple authKeys are used simultaneously, they need to be separated by commas.
 
 #### Requesting a token-protected **DeepLX API** instance using the `curl`
 ```
diff --git a/main.go b/main.go
index 231dcc14..f6697250 100644
--- a/main.go
+++ b/main.go
@@ -2,7 +2,7 @@
  * @Author: Vincent Young
  * @Date: 2023-07-01 21:45:34
  * @LastEditors: Vincent Young
- * @LastEditTime: 2023-11-27 15:10:06
+ * @LastEditTime: 2023-11-28 00:23:42
  * @FilePath: /DeepLX/main.go
  * @Telegram: https://t.me/missuo
  *
@@ -205,6 +205,40 @@ func translateByAPI(text string, targetLang string, sourceLang string, authKey s
 	return sb.String(), nil
 }
 
+type DeepLResponse struct {
+	CharacterCount int `json:"character_count"`
+	CharacterLimit int `json:"character_limit"`
+}
+
+func checkUsage(authKey string) (bool, error) {
+	url := "https://api-free.deepl.com/v2/usage"
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return false, err
+	}
+
+	req.Header.Add("Authorization", "DeepL-Auth-Key "+authKey)
+
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	if err != nil {
+		return false, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return false, err
+	}
+
+	var response DeepLResponse
+	err = json.Unmarshal(body, &response)
+	if err != nil {
+		return false, err
+	}
+	return response.CharacterCount < 499900, nil
+}
+
 func main() {
 	cfg := InitConfig()
 
@@ -352,22 +386,33 @@ func main() {
 		}
 
 		if resp.StatusCode == http.StatusTooManyRequests {
-			translatedText, err := translateByAPI(translateText, sourceLang, targetLang, cfg.AuthKey)
-			if err != nil {
-				c.JSON(http.StatusTooManyRequests, gin.H{
-					"code":    http.StatusTooManyRequests,
-					"message": "Too Many Requests",
-				})
-				return
+			authKeyArray := strings.Split(cfg.AuthKey, ",")
+			for _, authKey := range authKeyArray {
+				validity, err := checkUsage(authKey)
+				if err != nil {
+					continue
+				} else {
+					if validity == true {
+						translatedText, err := translateByAPI(translateText, sourceLang, targetLang, authKey)
+						if err != nil {
+							c.JSON(http.StatusTooManyRequests, gin.H{
+								"code":    http.StatusTooManyRequests,
+								"message": "Too Many Requests",
+							})
+						}
+						c.JSON(http.StatusOK, gin.H{
+							"code":        http.StatusOK,
+							"id":          1000000,
+							"data":        translatedText,
+							"source_lang": sourceLang,
+							"target_lang": targetLang,
+							"method":      "Official API",
+						})
+						return
+					}
+				}
+
 			}
-			c.JSON(http.StatusOK, gin.H{
-				"code":        http.StatusOK,
-				"id":          114514,
-				"data":        translatedText,
-				"source_lang": sourceLang,
-				"target_lang": targetLang,
-				"method":      "Official API",
-			})
 		} else {
 			var alternatives []string
 			res.Get("result.texts.0.alternatives").ForEach(func(key, value gjson.Result) bool {