优化 ChatGPTTranslator的错误处理和参数校验

Author: liscs

Mikoto/Translators/Implementations/ChatGPTTranslator.cs

@@ -1,6 +1,7 @@
 using Mikoto.Helpers.Network;
 using Mikoto.Translators.Interfaces;
 using System.Net.Http;
+using System.Text;
 using System.Text.Json;
 using System.Windows;
 
@@ -17,102 +18,126 @@ private ChatGPTTranslator() { }
         public static readonly string SIGN_UP_URL = "https://platform.openai.com";
         public static readonly string BILL_URL = "https://platform.openai.com/account/usage";
         public static readonly string DOCUMENT_URL = "https://platform.openai.com/docs/introduction/overview";
-        
+
         private string? openai_model = "gpt-3.5-turbo";
-        private string? apiKey; //ChatGPT翻译API的密钥
-        private string? apiUrl; //ChatGPT翻译API的URL
-        private string errorInfo = string.Empty; //错误信息
+        private string? apiKey; // ChatGPT 翻译 API 的密钥
+        private string? apiUrl; // ChatGPT 翻译 API 的 URL
+        private string lastErrorMessage = string.Empty; 
 
-        public string TranslatorDisplayName { get { return Application.Current.Resources["ChatGPTTranslator"].ToString()!; } }
+        public string TranslatorDisplayName => Application.Current.Resources["ChatGPTTranslator"]?.ToString() ?? "ChatGPT Translator";
 
         public string GetLastError()
         {
-            return errorInfo;
+            return lastErrorMessage;
         }
 
         public async Task<string?> TranslateAsync(string sourceText, string desLang, string srcLang)
         {
-            string q = sourceText;
-
-            if (sourceText == "" || desLang == "" || srcLang == "")
+            // 参数校验
+            if (string.IsNullOrWhiteSpace(sourceText) || string.IsNullOrWhiteSpace(desLang) || string.IsNullOrWhiteSpace(srcLang))
             {
-                errorInfo = "Param Missing";
+                SetError("Missing required parameters.");
                 return null;
             }
-            string retString;
-            string jsonParam = $"{{\"model\": \"{openai_model}\",\"messages\": [{{\"role\": \"system\", \"content\": \"Translate {srcLang} To {desLang}\"}},{{\"role\": \"user\", \"content\": \"{q}\"}}]}}";
+
+            var requestPayload = new
+            {
+                model = openai_model,
+                messages = new[]
+                {
+                    new { role = "system", content = $"Translate {srcLang} To {desLang}" },
+                    new { role = "user", content = sourceText }
+                }
+            };
+
+            string jsonParam = JsonSerializer.Serialize(requestPayload, TranslatorCommon.JsonSerializerOptions);
             var hc = CommonHttpClient.Instance;
-            var req = new StringContent(jsonParam, null, "application/json");
+            var req = new StringContent(jsonParam, Encoding.UTF8, "application/json");
             hc.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", apiKey);
+
             try
             {
-                HttpResponseMessage? httpResponseMessage = await hc.PostAsync(apiUrl, req);
-                retString = await httpResponseMessage.Content.ReadAsStringAsync();
+                using HttpResponseMessage httpResponseMessage = await hc.PostAsync(apiUrl, req);
+
+                // 检查 HTTP 状态码
+                if (!httpResponseMessage.IsSuccessStatusCode)
+                {
+                    string errorContent = await httpResponseMessage.Content.ReadAsStringAsync();
+                    HandleApiError(errorContent);
+                    return null;
+                }
+
+                string responseString = await httpResponseMessage.Content.ReadAsStringAsync();
+
+                // 解析 API 响应
+                if (JsonSerializer.Deserialize<ChatResponse>(responseString, TranslatorCommon.JsonSerializerOptions) is { } oinfo)
+                {
+                    return oinfo.choices.FirstOrDefault().message.content ?? HandleUnknownError(responseString);
+                }
+
+                return HandleUnknownError(responseString);
             }
             catch (HttpRequestException ex)
             {
-                errorInfo = ex.Message;
+                SetError($"Network error: {ex.Message}");
                 return null;
             }
             catch (TaskCanceledException ex)
             {
-                errorInfo = ex.Message;
+                SetError($"Request timeout: {ex.Message}");
                 return null;
             }
-            finally
-            {
-                req.Dispose();
-            }
-
-            ChatResponse oinfo;
-
-            try
+            catch (Exception ex)
             {
-                oinfo = JsonSerializer.Deserialize<ChatResponse>(retString, TranslatorCommon.JsonSerializerOptions);
-            }
-            catch
-            {
-                errorInfo = "JsonConvert Error";
+                SetError($"Unexpected error: {ex.Message}");
                 return null;
             }
-
-            try
-            {
-                return oinfo.choices[0].message.content;
-            }
-            catch
-            {
-                try
-                {
-                    var err = JsonSerializer.Deserialize<ChatResErr>(retString, TranslatorCommon.JsonSerializerOptions);
-                    errorInfo = err.error.message;
-                    return null;
-                }
-                catch
-                {
-                    errorInfo = "Unknown error";
-                    return null;
-                }
-            }
         }
 
         public static ITranslator TranslatorInit(params string[] param)
         {
             if (param.Length < 3)
                 throw new ArgumentException("Expected 3 parameters: API Key, API URL, Model");
 
-
-            ChatGPTTranslator chatGPTTranslator = new()
+            return new ChatGPTTranslator
             {
                 apiKey = param[0],
                 apiUrl = param[1],
                 openai_model = param[2],
             };
-            return chatGPTTranslator;
+        }
+
+        private void SetError(string message)
+        {
+            lastErrorMessage = message;
+        }
+
+        private string? HandleUnknownError(string response)
+        {
+            SetError($"Unknown API response: {response}");
+            return null;
+        }
+
+        private void HandleApiError(string errorContent)
+        {
+            try
+            {
+                if (JsonSerializer.Deserialize<ChatResErr>(errorContent, TranslatorCommon.JsonSerializerOptions) is ChatResErr err && err.error.code != null)
+                {
+                    SetError(err.error.message);
+                }
+                else
+                {
+                    HandleUnknownError(errorContent);
+                }
+            }
+            catch
+            {
+                HandleUnknownError(errorContent);
+            }
         }
     }
 
-#pragma warning disable 0649
     public struct ChatResponse
     {
         public string id;
@@ -156,3 +181,4 @@ public struct ChatError
         public object code;
     }
 }
+