Bugfix FXIOS-15230 [Translations Phase 2] Long-press active translate button to change language (#33157)

* Bugfix FXIOS-15230 [Translations Phase 2] Wire long-press on active translate button and filter original page language from picker

* Bugfix FXIOS-15230 [Translations Phase 2] Set bold attributed title after preferredAction to prevent reset

* Bugfix FXIOS-15230 [Translations Phase 2] Only show long-press on translate button when active

* Bugfix FXIOS-15230 [Translations Phase 2] Apply bold title after all actions, use source language for filtering in main menu

* Bugfix FXIOS-15230 [Translations Phase 2] Filter translated-to language from language picker

Author: razvanlitianu

firefox-ios/Client/Frontend/Browser/BrowserViewController/Views/BrowserViewController.swift

@@ -2936,21 +2936,7 @@ class BrowserViewController: UIViewController,
         if data.isTranslated, let langCode = data.translatedToLanguage {
             configureShowOriginalHeader(for: alert, languageCode: langCode)
         } else {
-            let title: String = .Translations.LanguagePicker.Title
-            let attributedTitleKey = "attributedTitle"
-            alert.title = title
-            alert.setValue(
-                NSAttributedString(
-                    string: title,
-                    attributes: [
-                        .font: DefaultDynamicFontHelper.preferredBoldFont(
-                            withTextStyle: .headline,
-                            size: UIFont.labelFontSize
-                        )
-                    ]
-                ),
-                forKey: attributedTitleKey
-            )
+            alert.title = .Translations.LanguagePicker.Title
         }
 
         data.languages.forEach { code in
@@ -2984,6 +2970,22 @@ class BrowserViewController: UIViewController,
             alert.addAction(UIAlertAction(title: .CancelString, style: .cancel))
         }
 
+        if let title = alert.title {
+            let attributedTitleKey = "attributedTitle"
+            alert.setValue(
+                NSAttributedString(
+                    string: title,
+                    attributes: [
+                        .font: DefaultDynamicFontHelper.preferredBoldFont(
+                            withTextStyle: .headline,
+                            size: UIFont.labelFontSize
+                        )
+                    ]
+                ),
+                forKey: attributedTitleKey
+            )
+        }
+
         if let popover = alert.popoverPresentationController {
             if let sourceButton {
                 popover.sourceView = sourceButton

firefox-ios/Client/Frontend/Browser/MainMenu/MainMenuCoordinator.swift

@@ -178,8 +178,10 @@ class MainMenuCoordinator: BaseCoordinator, LegacyFeatureFlaggable {
                 let manager = PreferredTranslationLanguagesManager(prefs: prefs)
                 let supported = await ASTranslationModelsFetcher.shared.fetchSupportedTargetLanguages()
                 let languages = manager.preferredLanguages(supportedTargetLanguages: supported)
-                let pageLanguage = try? await TranslationsService().detectPageLanguage(for: windowUUID)
-                let filteredLanguages = languages.filter { $0 != pageLanguage }
+                let pageLanguage = isTranslated
+                    ? translationConfig?.sourceLanguage
+                    : (try? await TranslationsService().detectPageLanguage(for: windowUUID))
+                let filteredLanguages = languages.filter { $0 != pageLanguage && $0 != translatedLanguage }
                 if isSingleLanguageFlow, let language = filteredLanguages.first, !isTranslated {
                     store.dispatch(TranslationLanguageSelectedAction(
                         windowUUID: windowUUID,

firefox-ios/Client/Frontend/Browser/Toolbars/Redux/ToolbarActionConfiguration.swift

@@ -58,6 +58,7 @@ struct ToolbarActionConfiguration: Equatable, LegacyFeatureFlaggable {
                actionType == .readerMode ||
                actionType == .readerModeWithSummarizer ||
                actionType == .summarizer ||
+               (actionType == .translate && isSelected) ||
                (actionType == .tabs && isShowingTopTabs == false)
     }
 }

firefox-ios/Client/Frontend/Browser/Toolbars/Redux/ToolbarMiddleware.swift

@@ -369,6 +369,9 @@ final class ToolbarMiddleware: LegacyFeatureFlaggable {
                                                   actionType: GeneralBrowserActionType.showSummarizer)
                 store.dispatch(action)
             }
+        case .translate:
+            // Long-press on translate is handled in TranslationsMiddleware.
+            break
         default:
             break
         }

firefox-ios/Client/Frontend/Browser/Toolbars/Redux/TranslationsConfiguration.swift

@@ -55,14 +55,17 @@ struct TranslationConfiguration: Equatable, LegacyFeatureFlaggable {
     let state: IconState?
     /// The language code the page was translated to, if in the active state (e.g. "en", "fr").
     let translatedToLanguage: String?
+    /// The original language of the page before translation (e.g. "de", "fr").
+    let sourceLanguage: String?
 
     // We initially set icon state as nil until we can detect the
     // web page and determine if we should show the translation icon
     // and set the icon to .inactive state.
-    init(prefs: Prefs, state: IconState? = nil, translatedToLanguage: String? = nil) {
+    init(prefs: Prefs, state: IconState? = nil, translatedToLanguage: String? = nil, sourceLanguage: String? = nil) {
         self.prefs = prefs
         self.state = state
         self.translatedToLanguage = translatedToLanguage
+        self.sourceLanguage = sourceLanguage
     }
 
     var isMultiLanguageFlow: Bool {
@@ -85,5 +88,6 @@ struct TranslationConfiguration: Equatable, LegacyFeatureFlaggable {
         return lhs.isTranslationFeatureEnabled == rhs.isTranslationFeatureEnabled
             && lhs.state == rhs.state
             && lhs.translatedToLanguage == rhs.translatedToLanguage
+            && lhs.sourceLanguage == rhs.sourceLanguage
     }
 }

firefox-ios/Client/Frontend/Translations/TranslationsMiddleware.swift

@@ -91,7 +91,6 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
     private func handleTappingOnTranslateButton(for action: ToolbarMiddlewareAction, and state: AppState) {
         guard let gestureType = action.gestureType,
               let type = action.buttonType,
-              gestureType == .tap,
               type == .translate
         else { return }
 
@@ -112,6 +111,20 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
             return
         }
 
+        if gestureType == .longPress {
+            guard translationConfiguration.state == .active,
+                  featureFlags.isFeatureEnabled(.translationLanguagePicker, checking: .buildOnly)
+            else { return }
+            showLanguagePickerForActiveTranslation(
+                for: action,
+                translatedToLanguage: translationConfiguration.translatedToLanguage,
+                sourceLanguage: translationConfiguration.sourceLanguage
+            )
+            return
+        }
+
+        guard gestureType == .tap else { return }
+
         if translationConfiguration.state == .inactive,
            featureFlags.isFeatureEnabled(.translationLanguagePicker, checking: .buildOnly) {
             let capturedButton = action.buttonTapped
@@ -160,6 +173,28 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
         }
     }
 
+    private func showLanguagePickerForActiveTranslation(
+        for action: ToolbarMiddlewareAction,
+        translatedToLanguage: String?,
+        sourceLanguage: String?
+    ) {
+        let capturedButton = action.buttonTapped
+        Task {
+            let manager = PreferredTranslationLanguagesManager(prefs: profile.prefs)
+            let supported = await translationsService.fetchSupportedTargetLanguages()
+            let languages = manager.preferredLanguages(supportedTargetLanguages: supported)
+            let filteredLanguages = languages.filter { $0 != sourceLanguage && $0 != translatedToLanguage }
+            store.dispatch(GeneralBrowserAction(
+                buttonTapped: capturedButton,
+                translationLanguages: filteredLanguages,
+                isPageTranslated: true,
+                translatedToLanguage: translatedToLanguage,
+                windowUUID: action.windowUUID,
+                actionType: GeneralBrowserActionType.showTranslationLanguagePicker
+            ))
+        }
+    }
+
     private func handleTappingRetryButtonOnToast(for action: TranslationsAction, and state: AppState) {
         guard let language = selectedTargetLanguages[action.windowUUID] else {
             logger.log(
@@ -318,10 +353,12 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
 
     private func performTranslation(for action: Action, targetLanguage: String, isPrivate: Bool, autoTranslate: Bool) async {
         do {
+            var detectedSourceLanguage: String?
             try await translationsService.translateCurrentPage(
                 for: action.windowUUID,
                 to: targetLanguage,
                 onLanguageIdentified: { identifiedLanguage, deviceLanguage in
+                    detectedSourceLanguage = identifiedLanguage
                     self.translationsTelemetry.pageLanguageIdentified(
                         identifiedLanguage: identifiedLanguage,
                         deviceLanguage: deviceLanguage
@@ -340,6 +377,7 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
                 for: ToolbarActionType.translationCompleted,
                 with: .active,
                 translatedToLanguage: targetLanguage,
+                sourceLanguage: detectedSourceLanguage,
                 and: action.windowUUID
             )
             maybeShowAutoTranslatePrompt(windowUUID: action.windowUUID)
@@ -386,13 +424,15 @@ final class TranslationsMiddleware: LegacyFeatureFlaggable {
         for actionType: ToolbarActionType,
         with state: TranslationConfiguration.IconState,
         translatedToLanguage: String? = nil,
+        sourceLanguage: String? = nil,
         and windowUUID: WindowUUID
     ) {
         let toolbarAction = ToolbarAction(
             translationConfiguration: TranslationConfiguration(
                 prefs: profile.prefs,
                 state: state,
-                translatedToLanguage: translatedToLanguage
+                translatedToLanguage: translatedToLanguage,
+                sourceLanguage: sourceLanguage
             ),
             windowUUID: windowUUID,
             actionType: actionType