Skip to content

Map saved Auto-Translate languages across providers #154

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
Blackspirits wants to merge 1 commit into
base: upl/review-base-dda1
Choose a base branch
from
Draft

Map saved Auto-Translate languages across providers #154

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
76 changes: 71 additions & 5 deletions src/ui/Features/Translate/AutoTranslateViewModel.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2457,8 +2457,11 @@ public static string EvaluateDefaultSourceLanguageCode(Encoding? encoding, Subti
// language, so it opened on German instead (#14926). The last source is a better guess.
if (string.IsNullOrEmpty(defaultSourceLanguageCode))
{
// The saved source belongs to the previously used engine. Its identifier may use a
// different convention (for example NLLB "eng_Latn" versus Google "en" or an LLM
// engine's "English"), so resolve it against the *current* engine before returning it.
var lastSource = Se.Settings.AutoTranslate.AutoTranslateLastSource;
return string.IsNullOrEmpty(lastSource) ? "en" : lastSource;
return FindLanguage(sourceLanguages, lastSource)?.Code ?? "en";
}

if (!string.IsNullOrEmpty(Se.Settings.AutoTranslate.AutoTranslateLastSource) &&
Expand Down Expand Up @@ -2523,13 +2526,76 @@ public static string EvaluateDefaultSourceLanguageCode(Encoding? encoding, Subti
return null;
}

var direct = languages.FirstOrDefault(p => codeOrName.Equals(p.Code, StringComparison.OrdinalIgnoreCase))
?? languages.FirstOrDefault(p => codeOrName.Equals(p.Name, StringComparison.OrdinalIgnoreCase))
?? languages.FirstOrDefault(p => codeOrName.Equals(p.TwoLetterIsoLanguageName, StringComparison.OrdinalIgnoreCase));
if (direct != null)
{
return direct;
}

// Providers disagree on the separator used by script-qualified identifiers:
// NLLB uses "zho_Hans", while another engine may expose the same identifier as
// "zho-Hans". Treat those spellings as the same before falling back to ISO mapping.
var normalized = NormalizeLanguageIdentifier(codeOrName);
var normalizedMatch = languages.FirstOrDefault(p =>
normalized.Equals(NormalizeLanguageIdentifier(p.Code), StringComparison.OrdinalIgnoreCase))
?? languages.FirstOrDefault(p =>
normalized.Equals(NormalizeLanguageIdentifier(p.TwoLetterIsoLanguageName), StringComparison.OrdinalIgnoreCase));
if (normalizedMatch != null)
{
return normalizedMatch;
}

var englishName = Iso639Dash2LanguageCode.List
.FirstOrDefault(l => l.TwoLetterCode.Equals(codeOrName, StringComparison.OrdinalIgnoreCase))?.EnglishName;
if (englishName != null)
{
var byEnglishName = languages.FirstOrDefault(p => englishName.Equals(p.Name, StringComparison.OrdinalIgnoreCase));
if (byEnglishName != null)
{
return byEnglishName;
}
}

// NLLB-style identifiers start with ISO-639-3 (eng_Latn, deu_Latn, ...). Convert that
// prefix to ISO-639-1, then prefer an exact English-name match. If the current engine has
// several variants sharing the same two-letter code and no exact name (e.g. Chinese
// variants), fail closed instead of silently selecting the first one.
var separatorIndex = normalized.IndexOf('-');
var threeLetter = separatorIndex > 0 ? normalized[..separatorIndex] : normalized;
if (threeLetter.Length != 3)
{
return null;
}

return languages.FirstOrDefault(p => codeOrName.Equals(p.Code, StringComparison.OrdinalIgnoreCase))
?? languages.FirstOrDefault(p => codeOrName.Equals(p.Name, StringComparison.OrdinalIgnoreCase))
?? languages.FirstOrDefault(p => codeOrName.Equals(p.TwoLetterIsoLanguageName, StringComparison.OrdinalIgnoreCase))
?? (englishName == null ? null : languages.FirstOrDefault(p => englishName.Equals(p.Name, StringComparison.OrdinalIgnoreCase)));
var twoLetter = Iso639Dash2LanguageCode.GetTwoLetterCodeFromThreeLetterCode(threeLetter);
if (string.IsNullOrEmpty(twoLetter))
{
return null;
}

englishName = Iso639Dash2LanguageCode.List
.FirstOrDefault(l => l.TwoLetterCode.Equals(twoLetter, StringComparison.OrdinalIgnoreCase))?.EnglishName;
if (englishName != null)
{
var byEnglishName = languages.FirstOrDefault(p => englishName.Equals(p.Name, StringComparison.OrdinalIgnoreCase));
if (byEnglishName != null)
{
return byEnglishName;
}
}

var matches = languages
.Where(p => twoLetter.Equals(p.TwoLetterIsoLanguageName, StringComparison.OrdinalIgnoreCase))
.Take(2)
.ToList();
return matches.Count == 1 ? matches[0] : null;
}

private static string NormalizeLanguageIdentifier(string? value)
{
return (value ?? string.Empty).Trim().Replace('_', '-');
}

private static bool IsSameLanguage(TranslationPair language, TranslationPair? other)
Expand Down
54 changes: 54 additions & 0 deletions tests/UI/Features/Translate/AutoTranslateModelAndSourceTests.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -105,6 +105,60 @@ public void UndetectableSource_UsesLastSource_NotEnglish()
}
}

[Fact]
public void UndetectableSource_NllbSavedCodeMapsToCurrentProvider()
{
var lastSource = Se.Settings.AutoTranslate.AutoTranslateLastSource;
try
{
var subtitle = new Subtitle();
subtitle.Paragraphs.Add(new Paragraph("...", 0, 1000));
var languages = new ObservableCollection<TranslationPair>(new GoogleTranslateV1().GetSupportedSourceLanguages());

Se.Settings.AutoTranslate.AutoTranslateLastSource = "eng_Latn";

Assert.Equal("en", AutoTranslateViewModel.EvaluateDefaultSourceLanguageCode(null, subtitle, languages));
}
finally
{
Se.Settings.AutoTranslate.AutoTranslateLastSource = lastSource;
}
}

[Fact]
public void LastNllbTarget_MapsToCurrentProviderLanguage()
{
var translator = new GeminiTranslate();
var targets = translator.GetSupportedTargetLanguages();
var source = translator.GetSupportedSourceLanguages().First(p => p.Name == "English");

var selected = AutoTranslateViewModel.FindDefaultTargetLanguage(
targets,
source,
lastTarget: "deu_Latn",
uiCultureName: "en-US");

Assert.NotNull(selected);
Assert.Equal("German", selected.Name);
}

[Fact]
public void ScriptQualifiedNllbTarget_PreservesVariantAcrossSeparatorConventions()
{
var translator = new GeminiTranslate();
var targets = translator.GetSupportedTargetLanguages();
var source = translator.GetSupportedSourceLanguages().First(p => p.Name == "English");

var selected = AutoTranslateViewModel.FindDefaultTargetLanguage(
targets,
source,
lastTarget: "zho_Hans",
uiCultureName: "en-US");

Assert.NotNull(selected);
Assert.Equal("Chinese (Simplified)", selected.Name);
}

[Fact]
public void DetectableSource_IsStillDetected()
{
Expand Down
Loading