Automatically detect language of posts, improve language detection when posting (#800)

* Use language detection to translate posts

The source language of a post is now determined via Apples internal language
detection, translation from the transmitted language is still possible.

* Make language detection posting more accessible

Language recognition is now always applied before posting, even if the user has
explicitly selected a different language. However, the user is always asked in
which of the two languages he wants to post.

* Add localizations

* Remove language detection in the timeline for now

The language detection in the timeline is for now removed to increase
timeline-performance.

Signed-off-by: Paul Schuetz <pa.schuetz@web.de>

* Show translate button even if no language is sent

The translate-button is shown even if no language is sent with the post.

Signed-off-by: Paul Schuetz <pa.schuetz@web.de>

* Adjust to new commits on main

Adjustments are made in regards to new developments on main.

Signed-off-by: Paul Schuetz <pa.schuetz@web.de>

---------

Signed-off-by: Paul Schuetz <pa.schuetz@web.de>
Co-authored-by: Thomas Ricouard <ricouard77@gmail.com>

IceCubesApp/Resources/Localization/ca.lproj/Localizable.strings

@@ -374,6 +374,8 @@
 "status.editor.error.upload" = "Error en la pujada";
 "status.editor.language-select.navigation-title" = "Selecciona la llengua";
 "status.editor.language-select.recently-used" = "Recents";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Edita la imatge";
 "status.editor.media.image-description" = "Descripció de la imatge";
 "status.editor.mode.edit" = "Edita la publicació";

IceCubesApp/Resources/Localization/de.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "Fehler beim Hochladen";
 "status.editor.language-select.navigation-title" = "Sprache auswählen";
 "status.editor.language-select.recently-used" = "Kürzlich genutzt";
+"status.editor.language-select.confirmation.detected-%@" = "Auf %@ posten (Erkannte Sprache)";
+"status.editor.language-select.confirmation.selected-%@" = "Auf %@ posten (Ausgewählte Sprache)";
 "status.editor.media.edit-image" = "Bild bearbeiten";
 "status.editor.media.image-description" = "Bildbeschreibung";
 "status.editor.mode.edit" = "Deinen Beitrag bearbeiten";

IceCubesApp/Resources/Localization/en-GB.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "Error uploading";
 "status.editor.language-select.navigation-title" = "Select Language";
 "status.editor.language-select.recently-used" = "Recently Used";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Edit Image";
 "status.editor.media.image-description" = "Image description";
 "status.editor.mode.edit" = "Editing your post";

IceCubesApp/Resources/Localization/en.lproj/Localizable.strings

@@ -376,6 +376,8 @@
 "status.editor.error.upload" = "Error uploading";
 "status.editor.language-select.navigation-title" = "Select Language";
 "status.editor.language-select.recently-used" = "Recently Used";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Edit Image";
 "status.editor.media.image-description" = "Image description";
 "status.editor.mode.edit" = "Editing your post";

IceCubesApp/Resources/Localization/es.lproj/Localizable.strings

@@ -376,6 +376,8 @@
 "status.editor.error.upload" = "Error subiendo";
 "status.editor.language-select.navigation-title" = "Seleccionar idioma";
 "status.editor.language-select.recently-used" = "Usado recientemente";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Editar Imagen";
 "status.editor.media.image-description" = "Descripción de la imagen";
 "status.editor.mode.edit" = "Editando tu publicación";

IceCubesApp/Resources/Localization/eu.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "Errorea igotzerakoan";
 "status.editor.language-select.navigation-title" = "Hautatu hizkuntza";
 "status.editor.language-select.recently-used" = "Duela gutxi erabilitakoak";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Editatu irudiak";
 "status.editor.media.image-description" = "Irudiaren deskribapena";
 "status.editor.mode.edit" = "Bidalketa editatzen";

IceCubesApp/Resources/Localization/fr.lproj/Localizable.strings

@@ -371,6 +371,8 @@
 "status.editor.error.upload" = "Erreur de téléchargement";
 "status.editor.language-select.navigation-title" = "Sélectionner la langue";
 "status.editor.language-select.recently-used" = "Utilisé récemment";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Modifier l'image";
 "status.editor.media.image-description" = "Description de l'image";
 "status.editor.mode.edit" = "Modification de votre publication";

IceCubesApp/Resources/Localization/it.lproj/Localizable.strings

@@ -376,6 +376,8 @@
 "status.editor.error.upload" = "Errore durante il caricamento";
 "status.editor.language-select.navigation-title" = "Scegli la lingua";
 "status.editor.language-select.recently-used" = "Usato recentemente";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Modifica l'immagine";
 "status.editor.media.image-description" = "Descrizione dell'immagine";
 "status.editor.mode.edit" = "Modifica post";

IceCubesApp/Resources/Localization/ja.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "アップロードエラー";
 "status.editor.language-select.navigation-title" = "言語設定";
 "status.editor.language-select.recently-used" = "最近使用した";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "イメージの編集";
 "status.editor.media.image-description" = "イメージの説明文";
 "status.editor.mode.edit" = "投稿を編集する";

IceCubesApp/Resources/Localization/ko.lproj/Localizable.strings

@@ -377,6 +377,8 @@
 "status.editor.error.upload" = "전송 오류";
 "status.editor.language-select.navigation-title" = "언어 선택";
 "status.editor.language-select.recently-used" = "최근 사용";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "이미지 편집";
 "status.editor.media.image-description" = "이미지 설명";
 "status.editor.mode.edit" = "글 수정";

IceCubesApp/Resources/Localization/nb.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "Feil ved opplasting";
 "status.editor.language-select.navigation-title" = "Velg språk";
 "status.editor.language-select.recently-used" = "Nylig brukt";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Rediger bilde";
 "status.editor.media.image-description" = "Bildebeskrivelse";
 "status.editor.mode.edit" = "Redigerer innlegget ditt";

IceCubesApp/Resources/Localization/nl.lproj/Localizable.strings

@@ -369,6 +369,8 @@
 "status.editor.error.upload" = "Fout tijdens uploaden";
 "status.editor.language-select.navigation-title" = "Taal selecteren";
 "status.editor.language-select.recently-used" = "Onlangs gebruikt";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Afbeelding bewerken";
 "status.editor.media.image-description" = "Omschrijving";
 "status.editor.mode.edit" = "Post bewerken";

IceCubesApp/Resources/Localization/pl.lproj/Localizable.strings

@@ -371,6 +371,8 @@
 "status.editor.error.upload" = "Błąd wysyłania";
 "status.editor.language-select.navigation-title" = "Wybierz język";
 "status.editor.language-select.recently-used" = "Ostatnio użyty";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Edytuj obrazek";
 "status.editor.media.image-description" = "Opis obrazka";
 "status.editor.mode.edit" = "Edycja twojego postu";

IceCubesApp/Resources/Localization/pt-BR.lproj/Localizable.strings

@@ -375,6 +375,8 @@
 "status.editor.error.upload" = "Erro ao fazer upload";
 "status.editor.language-select.navigation-title" = "Selecionar Idioma";
 "status.editor.language-select.recently-used" = "Usado recentemente";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Editar Imagem";
 "status.editor.media.image-description" = "Descrição da imagem";
 "status.editor.mode.edit" = "Editando sua postagem";

IceCubesApp/Resources/Localization/tr.lproj/Localizable.strings

@@ -371,6 +371,8 @@
 "status.editor.error.upload" = "Yüklerken Hata Oluştu";
 "status.editor.language-select.navigation-title" = "Dil Seç";
 "status.editor.language-select.recently-used" = "Son Kullanılanlar";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "Görüntüyü Düzenle";
 "status.editor.media.image-description" = "Görüntü Açıklaması";
 "status.editor.mode.edit" = "Gönderin Düzenleniyor";

IceCubesApp/Resources/Localization/zh-Hans.lproj/Localizable.strings

@@ -376,6 +376,8 @@
 "status.editor.error.upload" = "上传错误";
 "status.editor.language-select.navigation-title" = "选择语言";
 "status.editor.language-select.recently-used" = "最近使用";
+"status.editor.language-select.confirmation.detected-%@" = "Post in %@ (Detected language)";
+"status.editor.language-select.confirmation.selected-%@" = "Post in %@ (Selected language)";
 "status.editor.media.edit-image" = "编辑图片";
 "status.editor.media.image-description" = "图片描述";
 "status.editor.mode.edit" = "正在编辑你的嘟文";

Packages/Status/Sources/Status/Editor/StatusEditorView.swift

@@ -21,6 +21,7 @@ public struct StatusEditorView: View {
   @FocusState private var isSpoilerTextFocused: Bool
 
   @State private var isDismissAlertPresented: Bool = false
+    @State private var isLanguageConfirmPresented = false
 
   public init(mode: StatusEditorViewModel.Mode) {
     _viewModel = StateObject(wrappedValue: .init(mode: mode))
@@ -104,12 +105,12 @@ public struct StatusEditorView: View {
         ToolbarItem(placement: .navigationBarTrailing) {
           Button {
             Task {
-              let status = await viewModel.postStatus()
+                viewModel.evaluateLanguages()
-              if status != nil {
+                if let _ = viewModel.languageConfirmationDialogLanguages {
-                dismiss()
+                    isLanguageConfirmPresented = true
-                NotificationCenter.default.post(name: NotificationsName.shareSheetClose,
+                } else {
-                                                object: nil)
+                    await postStatus()
-              }
+                }
             }
           } label: {
             if viewModel.isPosting {
@@ -120,6 +121,9 @@ public struct StatusEditorView: View {
           }
           .disabled(!viewModel.canPost)
           .keyboardShortcut(.return, modifiers: .command)
+          .confirmationDialog("", isPresented: $isLanguageConfirmPresented, actions: {
+              languageConfirmationDialog
+          })
         }
         ToolbarItem(placement: .navigationBarLeading) {
           Button {
@@ -156,6 +160,42 @@ public struct StatusEditorView: View {
     .interactiveDismissDisabled(!viewModel.statusText.string.isEmpty)
   }
 
+    @ViewBuilder
+    private var languageConfirmationDialog: some View {
+        if let dialogVals = viewModel.languageConfirmationDialogLanguages,
+           let detected = dialogVals["detected"],
+           let detectedLong = Locale.current.localizedString(forLanguageCode: detected),
+           let selected = dialogVals["selected"],
+           let selectedLong = Locale.current.localizedString(forLanguageCode: selected){
+            Button("status.editor.language-select.confirmation.detected-\(detectedLong)") {
+                viewModel.selectedLanguage = detected
+                Task {
+                    await postStatus()
+                }
+            }
+            Button("status.editor.language-select.confirmation.selected-\(selectedLong)") {
+                viewModel.selectedLanguage = selected
+                Task {
+                    await postStatus()
+                }
+            }
+            Button("action.cancel", role: .cancel) {
+                viewModel.languageConfirmationDialogLanguages = nil
+            }
+        } else {
+            EmptyView()
+        }
+    }
+    
+    private func postStatus() async {
+        let status = await viewModel.postStatus()
+        if status != nil {
+            dismiss()
+            NotificationCenter.default.post(name: NotificationsName.shareSheetClose,
+                                            object: nil)
+        }
+    }
+
   @ViewBuilder
   private var spoilerTextView: some View {
     if viewModel.spoilerOn {

Packages/Status/Sources/Status/Editor/StatusEditorViewModel.swift

@@ -14,6 +14,7 @@ public class StatusEditorViewModel: NSObject, ObservableObject {
   var currentAccount: Account?
   var theme: Theme?
   var preferences: UserPreferences?
+  var languageConfirmationDialogLanguages: [String: String]?
 
   var textView: UITextView? {
     didSet {
@@ -141,6 +142,17 @@ public class StatusEditorViewModel: NSObject, ObservableObject {
     selectedLanguage = selectedLanguage ?? preference ?? currentAccount?.source?.language
   }
 
+    func evaluateLanguages(){
+        if let detectedLang = detectLanguage(text: statusText.string),
+           let selectedLanguage = selectedLanguage,
+           selectedLanguage != detectedLang {
+            languageConfirmationDialogLanguages = ["detected": detectedLang,
+                                                   "selected": selectedLanguage]
+        } else {
+            languageConfirmationDialogLanguages = nil;
+        }
+    }
+
   func postStatus() async -> Status? {
     guard let client else { return nil }
     do {
@@ -153,20 +165,6 @@ public class StatusEditorViewModel: NSObject, ObservableObject {
                          expires_in: pollDuration.rawValue)
       }
 
-      if !hasExplicitlySelectedLanguage {
-        // Attempt language resolution using Natural Language
-        let recognizer = NLLanguageRecognizer()
-        recognizer.processString(statusText.string)
-        // Use languageHypotheses to get the probability with it
-        let hypotheses = recognizer.languageHypotheses(withMaximum: 1)
-        // Assert that 85% probability is enough :)
-        // A one word toot that is en/fr compatible is only ~50% confident, for instance
-        if let (language, probability) = hypotheses.first, probability > 0.85 {
-          // rawValue return the IETF BCP 47 language tag
-          selectedLanguage = language.rawValue
-        }
-      }
-
       let data = StatusData(status: statusText.string,
                             visibility: visibility,
                             inReplyToId: mode.replyToStatus?.id,

Packages/Status/Sources/Status/LanguageDetection/LanguageDetection.swift

@@ -0,0 +1,34 @@
+import Foundation
+import NaturalLanguage
+
+private func stripToPureLanguage(inText: String) -> String {
+    let hashtagRegex = try! Regex("#[\\w]*")
+    let emojiRegex = try! Regex(":\\w*:")
+    let atRegex = try! Regex("@\\w*")
+    
+    var resultStr = inText
+    
+    [hashtagRegex, emojiRegex, atRegex].forEach { regex in
+        let splitArray = resultStr.split(separator: regex, omittingEmptySubsequences: true)
+        resultStr = splitArray.joined() as String
+    }
+    
+    return resultStr.trimmingCharacters(in: .whitespacesAndNewlines)
+}
+
+func detectLanguage(text: String) -> String? {
+    let recognizer = NLLanguageRecognizer()
+    
+    let strippedText = stripToPureLanguage(inText: text)
+    
+    recognizer.processString(strippedText)
+    
+    let hypotheses = recognizer.languageHypotheses(withMaximum: 1)
+    
+    // Use the detected language only with >= 85 % confidence
+    if let (lang, confidence) = hypotheses.first, confidence >= 0.85 {
+        return lang.rawValue
+    } else {
+        return nil
+    }
+}

Packages/Status/Sources/Status/Row/StatusRowContextMenu.swift

@@ -82,9 +82,8 @@ struct StatusRowContextMenu: View {
           await viewModel.translate(userLang: lang)
         }
       } label: {
-        if let statusLang = viewModel.status.language,
+        if let statusLang = viewModel.getStatusLang(),
-           let languageName = Locale.current.localizedString(forLanguageCode: statusLang)
+           let languageName = Locale.current.localizedString(forLanguageCode: statusLang) {
-        {
           Label("status.action.translate-from-\(languageName)", systemImage: "captions.bubble")
         } else {
           Label("status.action.translate", systemImage: "captions.bubble")

Packages/Status/Sources/Status/Row/StatusRowView.swift

@@ -345,14 +345,24 @@ public struct StatusRowView: View {
     .accessibilityHidden(true)
   }
 
+    private func shouldShowTranslateButton(status: AnyStatus) -> Bool {
+        let statusLang = viewModel.getStatusLang()
+        
+        if let userLang = preferences.serverPreferences?.postLanguage,
+           preferences.showTranslateButton,
+           !status.content.asRawText.isEmpty,
+           viewModel.translation == nil
+        {
+            return userLang != statusLang
+        } else {
+            return false
+        }
+    }
+
   @ViewBuilder
   private func makeTranslateView(status: AnyStatus) -> some View {
-    if let userLang = preferences.serverPreferences?.postLanguage,
+      if let userLang = preferences.serverPreferences?.postLanguage,
-       preferences.showTranslateButton,
+       shouldShowTranslateButton(status: status)
-       status.language != nil,
-       userLang != status.language,
-       !status.content.asRawText.isEmpty,
-       viewModel.translation == nil
     {
       Button {
         Task {
@@ -362,13 +372,13 @@ public struct StatusRowView: View {
         if viewModel.isLoadingTranslation {
           ProgressView()
         } else {
-          if let statusLanguage = status.language,
+            if let statusLanguage = viewModel.getStatusLang(),
-             let languageName = Locale.current.localizedString(forLanguageCode: statusLanguage)
+               let languageName = Locale.current.localizedString(forLanguageCode: statusLanguage)
-          {
+            {
-            Text("status.action.translate-from-\(languageName)")
+                Text("status.action.translate-from-\(languageName)")
-          } else {
+            } else {
-            Text("status.action.translate")
+                Text("status.action.translate")
-          }
+            }
         }
       }
       .buttonStyle(.borderless)

Packages/Status/Sources/Status/Row/StatusRowViewModel.swift

@@ -2,6 +2,7 @@ import Env
 import Models
 import Network
 import SwiftUI
+import NaturalLanguage
 
 import DesignSystem
 
@@ -289,8 +290,16 @@ public class StatusRowViewModel: ObservableObject {
     reblogsCount = status.reblog?.reblogsCount ?? status.reblogsCount
     repliesCount = status.reblog?.repliesCount ?? status.repliesCount
   }
-
+    
+    func getStatusLang() -> String? {
+        status.language
+    }
+    
   func translate(userLang: String) async {
+    await translate(userLang: userLang, sourceLang: getStatusLang())
+  }
+    
+  private func translate(userLang: String, sourceLang: String?) async {
     guard let client else { return }
     do {
       withAnimation {