Port and harden API-Route auto-translation integration

Changelog.txt

@@ -6,6 +6,7 @@ Subtitle Edit Changelog
   A summary of the changes since 5.1.0:
 
 New features:
+* Add API-Route to Auto-translate - thx DennyHo0917
 * Assisted split and Assisted move - ranked one-click suggestions with full previews
 * Chapter editor with Matroska/MP4/OGM chapter formats (Video > More > Chapters)
 * Edit original - edit the original reference rows in place, open a non-matching original as a read-only reference, and show the original subtitle on the waveform

src/libse/Settings/ToolsSettings.cs

@@ -59,6 +59,10 @@ public class ToolsSettings
         public string AvalAiPrompt { get; set; }
         public string AvalAiApiKey { get; set; }
         public string AvalAiModel { get; set; }
+        public string ApiRouteUrl { get; set; }
+        public string ApiRoutePrompt { get; set; }
+        public string ApiRouteApiKey { get; set; }
+        public string ApiRouteModel { get; set; }
 
         public string PerplexityUrl { get; set; }
         public string PerplexityPrompt { get; set; }
@@ -167,6 +171,9 @@ public ToolsSettings()
             AvalAiUrl = "https://api.avalai.ir/v1/chat/completions";
             AvalAiPrompt = "Translate from {0} to {1}, keep punctuation as input, keep line breaks exactly the same, do not censor the translation, give only the output without comments:";
             AvalAiModel = "gpt-5.6-sol"; // AvalAi.Models[0] in LibUiLogic
+            ApiRouteUrl = "https://global.api-route.com/v1/chat/completions";
+            ApiRoutePrompt = "Translate from {0} to {1}, keep punctuation as input, keep line breaks exactly the same, do not censor the translation, give only the output without comments:";
+            ApiRouteModel = "gpt-5.6-sol"; // ApiRouteTranslate.Models[0] in LibUiLogic; keep in sync with API-Route pricing
             OpenRouterUrl = "https://openrouter.ai/api/v1/chat/completions";
             OpenRouterPrompt = "Translate from {0} to {1}, keep punctuation as input, keep line breaks exactly the same, do not censor the translation, give only the output without comments:";
             OpenRouterModel = "openai/gpt-5.6-sol"; // OpenRouterTranslate.Models[0] in LibUiLogic

src/libuilogic/AutoTranslate/ApiRouteTranslate.cs

@@ -0,0 +1,163 @@
+using Nikse.SubtitleEdit.Core.Common;
+using Nikse.SubtitleEdit.Core.Settings;
+using Nikse.SubtitleEdit.Core.SubtitleFormats;
+using Nikse.SubtitleEdit.UiLogic.Translate;
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Nikse.SubtitleEdit.UiLogic.Http;
+
+namespace Nikse.SubtitleEdit.UiLogic.AutoTranslate
+{
+    public class ApiRouteTranslate : IAutoTranslator, IDisposable
+    {
+        private HttpClient _httpClient = null!;
+
+        public static string StaticName { get; set; } = "API-Route";
+        public override string ToString() => StaticName;
+        public string Name => StaticName;
+        public string Url => "https://www.api-route.com";
+        public string Error { get; set; } = string.Empty;
+        public int MaxCharacters => 1500;
+
+        /// <summary>
+        /// See https://www.api-route.com
+        /// </summary>
+        /// <summary>
+        /// Current model suggestions from API-Route's pricing catalogue. The service documents
+        /// that availability changes over time, so the UI keeps the model field editable and this
+        /// list must not be treated as an exhaustive capability contract.
+        /// </summary>
+        public static string[] Models =>
+        [
+            "gpt-5.6-sol",
+            "claude-sonnet-4-6",
+            "gemini-3.1-pro",
+            "deepseek-v4-pro",
+            "grok-4.5",
+            "qwen/qwen3.5-plus-20260420",
+        ];
+
+        /// <summary>
+        /// Endpoint used when the url in settings is only the service base - see <see cref="AutoTranslateUrl"/>.
+        /// </summary>
+        public const string DefaultUrl = "https://global.api-route.com/v1/chat/completions";
+
+        public void Initialize()
+        {
+            _httpClient?.Dispose();
+            _httpClient = HttpClientFactoryWithProxy.CreateHttpClientWithProxy();
+            _httpClient.DefaultRequestHeaders.TryAddWithoutValidation("Content-Type", "application/json");
+            _httpClient.DefaultRequestHeaders.TryAddWithoutValidation("accept", "application/json");
+            _httpClient.BaseAddress = new Uri(AutoTranslateUrl.Complete(Configuration.Settings.Tools.ApiRouteUrl, DefaultUrl));
+            _httpClient.Timeout = TimeSpan.FromMinutes(15);
+
+            if (!string.IsNullOrEmpty(Configuration.Settings.Tools.ApiRouteApiKey))
+            {
+                _httpClient.DefaultRequestHeaders.TryAddWithoutValidation("Authorization", "Bearer " + Configuration.Settings.Tools.ApiRouteApiKey);
+            }
+        }
+
+        public List<TranslationPair> GetSupportedSourceLanguages()
+        {
+            return ListLanguages();
+        }
+
+        public List<TranslationPair> GetSupportedTargetLanguages()
+        {
+            return ListLanguages();
+        }
+
+        public async Task<string> Translate(string text, string sourceLanguageCode, string targetLanguageCode, CancellationToken cancellationToken)
+        {
+            var model = Configuration.Settings.Tools.ApiRouteModel;
+            if (string.IsNullOrEmpty(model))
+            {
+                model = Models[0];
+                Configuration.Settings.Tools.ApiRouteModel = model;
+            }
+
+            if (string.IsNullOrEmpty(Configuration.Settings.Tools.ApiRoutePrompt))
+            {
+                Configuration.Settings.Tools.ApiRoutePrompt = new ToolsSettings().ApiRoutePrompt;
+            }
+            var prompt = string.Format(Configuration.Settings.Tools.ApiRoutePrompt, sourceLanguageCode, targetLanguageCode);
+            var input = BuildRequestBody(model, prompt, text);
+
+            int[] retryDelays = { 2555, 5007, 9013 };
+            HttpResponseMessage result = null!;
+            var json = string.Empty;
+            for (var attempt = 0; attempt <= retryDelays.Length; attempt++)
+            {
+                var content = new StringContent(input, Encoding.UTF8);
+                content.Headers.ContentType = MediaTypeHeaderValue.Parse("application/json");
+                result = await _httpClient.PostAsync(string.Empty, content, cancellationToken);
+                var bytes = await result.Content.ReadAsByteArrayAsync(cancellationToken);
+                json = Encoding.UTF8.GetString(bytes).Trim();
+
+                if (!DeepLTranslate.ShouldRetry(result, json) || attempt == retryDelays.Length)
+                {
+                    break;
+                }
+
+                await Task.Delay(retryDelays[attempt], cancellationToken);
+            }
+
+            if (!result.IsSuccessStatusCode)
+            {
+                Error = json;
+                SeLogger.Error("API-Route Translate failed calling API: Status code=" + result.StatusCode + Environment.NewLine + json);
+            }
+
+            result.EnsureSuccessStatusCode();
+
+            var parser = new SeJsonParser();
+            var resultText = parser.GetFirstObject(json, "content");
+            if (resultText == null)
+            {
+                return string.Empty;
+            }
+
+            var outputText = Json.DecodeJsonText(resultText).Trim();
+            if (outputText.StartsWith('"') && outputText.EndsWith('"') && !text.StartsWith('"'))
+            {
+                outputText = outputText.Trim('"').Trim();
+            }
+
+            outputText = ChatGptTranslate.FixNewLines(outputText);
+            outputText = ChatGptTranslate.RemovePreamble(text, outputText);
+            outputText = ChatGptTranslate.DecodeUnicodeEscapes(outputText);
+            return outputText.Trim();
+        }
+
+        internal static string BuildRequestBody(string model, string prompt, string text)
+        {
+            return System.Text.Json.JsonSerializer.Serialize(new
+            {
+                model,
+                messages = new[]
+                {
+                    new
+                    {
+                        role = "user",
+                        content = prompt + "\n\n" + text.Trim(),
+                    },
+                },
+            });
+        }
+
+        public static List<TranslationPair> ListLanguages()
+        {
+            return ChatGptTranslate.ListLanguages();
+        }
+
+        public void Dispose()
+        {
+            _httpClient?.Dispose();
+        }
+    }
+}

src/ui/Features/Translate/AutoTranslateViewModel.cs

@@ -163,6 +163,7 @@ public AutoTranslateViewModel(IWindowService windowService, IFolderHelper folder
             new AnthropicTranslate(),
             new GroqTranslate(),
             new OpenRouterTranslate(),
+            new ApiRouteTranslate(),
             new LaraTranslate(),
             new PerplexityTranslate(),
             new GeminiTranslate(),
@@ -214,6 +215,11 @@ private void LoadSettings()
         // the url box and the translator fell back to the built-in endpoint on the next start.
         Configuration.Settings.Tools.OpenRouterUrl = Se.Settings.AutoTranslate.OpenRouterUrl;
 
+        Configuration.Settings.Tools.ApiRouteApiKey = Se.Settings.AutoTranslate.ApiRouteApiKey;
+        Configuration.Settings.Tools.ApiRouteUrl = Se.Settings.AutoTranslate.ApiRouteUrl;
+        Configuration.Settings.Tools.ApiRouteModel = Se.Settings.AutoTranslate.ApiRouteModel;
+        Configuration.Settings.Tools.ApiRoutePrompt = Se.Settings.AutoTranslate.ApiRoutePrompt;
+
         Configuration.Settings.Tools.ChatGptApiKey = Se.Settings.AutoTranslate.ChatGptApiKey;
         Configuration.Settings.Tools.ChatGptUrl = Se.Settings.AutoTranslate.ChatGptUrl;
         Configuration.Settings.Tools.ChatGptModel = Se.Settings.AutoTranslate.ChatGptModel;
@@ -468,6 +474,14 @@ public void SaveSettings()
             Se.Settings.AutoTranslate.OpenRouterUrl = apiUrl.Trim();
         }
 
+        if (engineType == typeof(ApiRouteTranslate))
+        {
+            Configuration.Settings.Tools.ApiRouteApiKey = apiKey.Trim();
+            Configuration.Settings.Tools.ApiRouteModel = apiModel.Trim();
+            Configuration.Settings.Tools.ApiRouteUrl = apiUrl.Trim();
+            Se.Settings.AutoTranslate.ApiRouteUrl = apiUrl.Trim();
+        }
+
         if (engineType == typeof(GeminiTranslate))
         {
             Configuration.Settings.Tools.GeminiProApiKey = apiKey.Trim();
@@ -520,6 +534,11 @@ public void SaveSettings()
         Se.Settings.AutoTranslate.OpenRouterModel = Configuration.Settings.Tools.OpenRouterModel;
         Se.Settings.AutoTranslate.OpenRouterPrompt = Configuration.Settings.Tools.OpenRouterPrompt;
 
+        Se.Settings.AutoTranslate.ApiRouteApiKey = Configuration.Settings.Tools.ApiRouteApiKey;
+        Se.Settings.AutoTranslate.ApiRouteUrl = Configuration.Settings.Tools.ApiRouteUrl;
+        Se.Settings.AutoTranslate.ApiRouteModel = Configuration.Settings.Tools.ApiRouteModel;
+        Se.Settings.AutoTranslate.ApiRoutePrompt = Configuration.Settings.Tools.ApiRoutePrompt;
+
         Se.Settings.AutoTranslate.ChatGptApiKey = Configuration.Settings.Tools.ChatGptApiKey;
         Se.Settings.AutoTranslate.ChatGptUrl = Configuration.Settings.Tools.ChatGptUrl;
         Se.Settings.AutoTranslate.ChatGptModel = Configuration.Settings.Tools.ChatGptModel;
@@ -1751,6 +1770,7 @@ private static string GetConfiguredApiUrl(IAutoTranslator translator)
             AnthropicTranslate => settings.AnthropicApiUrl,
             GroqTranslate => settings.GroqUrl,
             OpenRouterTranslate => settings.OpenRouterUrl,
+            ApiRouteTranslate => settings.ApiRouteUrl,
             LaraTranslate => settings.LaraUrl,
             PerplexityTranslate => settings.PerplexityUrl,
             NvidiaTranslate => settings.NvidiaUrl,
@@ -2294,6 +2314,24 @@ private void SetAutoTranslatorEngine(IAutoTranslator translator)
             return;
         }
 
+        if (engineType == typeof(ApiRouteTranslate))
+        {
+            FillUrls(new List<string>
+            {
+                Configuration.Settings.Tools.ApiRouteUrl,
+            });
+
+            ApiKeyText = Configuration.Settings.Tools.ApiRouteApiKey;
+            ApiKeyIsVisible = true;
+
+            _apiModels = ApiRouteTranslate.Models.ToList();
+            ModelIsVisible = true;
+            ButtonModelIsVisible = true;
+            ModelText = string.IsNullOrEmpty(Configuration.Settings.Tools.ApiRouteModel) ? _apiModels[0] : Configuration.Settings.Tools.ApiRouteModel;
+
+            return;
+        }
+
         if (engineType == typeof(GeminiTranslate))
         {
             ApiKeyText = Configuration.Settings.Tools.GeminiProApiKey;

src/ui/Features/Translate/TranslateSettingsViewModel.cs

@@ -74,6 +74,7 @@ private async Task Ok()
             engineType == typeof(PerplexityTranslate) ||
             engineType == typeof(GroqTranslate) ||
             engineType == typeof(OpenRouterTranslate) ||
+            engineType == typeof(ApiRouteTranslate) ||
             engineType == typeof(NvidiaTranslate) ||
             engineType == typeof(MistralTranslate) ||
             engineType == typeof(GeminiTranslate) ||
@@ -167,6 +168,11 @@ public void SaveValues()
                 Se.Settings.AutoTranslate.OpenRouterPrompt = PromptText;
                 Configuration.Settings.Tools.OpenRouterPrompt = PromptText;
             }
+            else if (engineType == typeof(ApiRouteTranslate))
+            {
+                Se.Settings.AutoTranslate.ApiRoutePrompt = PromptText;
+                Configuration.Settings.Tools.ApiRoutePrompt = PromptText;
+            }
             else if (engineType == typeof(NvidiaTranslate))
             {
                 Se.Settings.AutoTranslate.NvidiaPrompt = PromptText;
@@ -280,6 +286,11 @@ public void LoadValues(IAutoTranslator translator)
             return settings.OpenRouterPrompt;
         }
 
+        if (engineType == typeof(ApiRouteTranslate))
+        {
+            return settings.ApiRoutePrompt;
+        }
+
         if (engineType == typeof(NvidiaTranslate))
         {
             return settings.NvidiaPrompt;

src/ui/Logic/Config/SeAutoTranslate.cs

@@ -90,6 +90,10 @@ public class SeAutoTranslate
     public string AvalAiPrompt { get; set; }
     public string AvalAiApiKey { get; set; }
     public string AvalAiModel { get; set; }
+    public string ApiRouteUrl { get; set; }
+    public string ApiRoutePrompt { get; set; }
+    public string ApiRouteApiKey { get; set; }
+    public string ApiRouteModel { get; set; }
 
     public string PerplexityUrl { get; set; }
     public string PerplexityPrompt { get; set; }
@@ -127,6 +131,10 @@ public SeAutoTranslate()
         AvalAiModel = AvalAi.Models[0];
         AvalAiPrompt = "Translate from {0} to {1}, keep punctuation as input, do not censor the translation, give only the output without comments:";
         AvalAiUrl = AvalAi.DefaultUrl;
+        ApiRouteApiKey = string.Empty;
+        ApiRouteModel = ApiRouteTranslate.Models[0];
+        ApiRoutePrompt = "Translate from {0} to {1}, keep punctuation as input, keep line breaks exactly the same, do not censor the translation, give only the output without comments:";
+        ApiRouteUrl = ApiRouteTranslate.DefaultUrl;
         PerplexityApiKey = string.Empty;
         PerplexityModel = PerplexityTranslate.Models[0];
         PerplexityPrompt = "Translate from {0} to {1}, keep punctuation as input, do not censor the translation, give only the output without comments:";

src/ui/Logic/Se4Setup/Se4SettingsXmlImporter.cs

@@ -330,6 +330,10 @@ public static void ApplyAutoTranslate(Se4SettingsFile file)
         yield return ("AvalAiPrompt", v => t.AvalAiPrompt = v);
         yield return ("AvalAiApiKey", v => t.AvalAiApiKey = v);
         yield return ("AvalAiModel", v => t.AvalAiModel = v);
+        yield return ("ApiRouteUrl", v => t.ApiRouteUrl = v);
+        yield return ("ApiRoutePrompt", v => t.ApiRoutePrompt = v);
+        yield return ("ApiRouteApiKey", v => t.ApiRouteApiKey = v);
+        yield return ("ApiRouteModel", v => t.ApiRouteModel = v);
         yield return ("OpenRouterUrl", v => t.OpenRouterUrl = v);
         yield return ("OpenRouterPrompt", v => t.OpenRouterPrompt = v);
         yield return ("OpenRouterApiKey", v => t.OpenRouterApiKey = v);

tests/UI/Features/TranslateSettingsResetPromptTests.cs

@@ -4,6 +4,7 @@
 using Avalonia.Controls;
 using Avalonia.Headless.XUnit;
 using Avalonia.LogicalTree;
+using Nikse.SubtitleEdit.Core.Common;
 using Nikse.SubtitleEdit.Features.Translate;
 using Nikse.SubtitleEdit.Logic.Config;
 using Nikse.SubtitleEdit.UiLogic.AutoTranslate;
@@ -99,4 +100,39 @@ public void TranslateSettingsWindow_HidesResetPromptButtonForEngineWithoutPrompt
         Assert.NotNull(button);
         Assert.False(button!.IsEffectivelyVisible);
     }
+    [AvaloniaFact]
+    public void ApiRoutePrompt_IsVisibleResettableAndSaved()
+    {
+        var savedPrompt = Se.Settings.AutoTranslate.ApiRoutePrompt;
+        var savedCorePrompt = Configuration.Settings.Tools.ApiRoutePrompt;
+        try
+        {
+            Se.Settings.AutoTranslate.ApiRoutePrompt = "My API-Route prompt from {0} to {1}";
+            Configuration.Settings.Tools.ApiRoutePrompt = Se.Settings.AutoTranslate.ApiRoutePrompt;
+
+            var vm = new TranslateSettingsViewModel();
+            vm.LoadValues(new ApiRouteTranslate());
+
+            Assert.True(vm.PromptIsVisible);
+            Assert.Equal("My API-Route prompt from {0} to {1}", vm.PromptText);
+
+            vm.ResetPromptCommand.Execute(null);
+
+            var builtIn = new SeAutoTranslate().ApiRoutePrompt;
+            Assert.Contains("keep line breaks exactly the same", builtIn);
+            Assert.Equal(builtIn, vm.PromptText);
+
+            vm.PromptText = "Saved API-Route prompt from {0} to {1}";
+            vm.SaveValues();
+
+            Assert.Equal(vm.PromptText, Se.Settings.AutoTranslate.ApiRoutePrompt);
+            Assert.Equal(vm.PromptText, Configuration.Settings.Tools.ApiRoutePrompt);
+        }
+        finally
+        {
+            Se.Settings.AutoTranslate.ApiRoutePrompt = savedPrompt;
+            Configuration.Settings.Tools.ApiRoutePrompt = savedCorePrompt;
+        }
+    }
+
 }