content: Follow browser preference setting when opening links

Signed-off-by: Zixuan James Li <[email protected]>

Author: PIG208

Diff for: lib/model/settings.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/foundation.dart';
 
 import '../generated/l10n/zulip_localizations.dart';
+import 'database.dart';
 
 /// The visual theme of the app.
 ///
@@ -44,3 +45,19 @@ enum BrowserPreference {
   /// Use the user's default browser app.
   external,
 }
+
+extension GlobalSettingsHelpers on GlobalSettingsData {
+  BrowserPreference get effectiveBrowserPreference {
+    if (browserPreference != null) {
+      return browserPreference!;
+    }
+    return switch (defaultTargetPlatform) {
+      // On iOS we prefer LaunchMode.externalApplication because (for
+      // HTTP URLs) LaunchMode.platformDefault uses SFSafariViewController,
+      // which gives an awkward UX as described here:
+      //  https://chat.zulip.org/#narrow/stream/48-mobile/topic/in-app.20browser/near/1169118
+      TargetPlatform.iOS => BrowserPreference.external,
+      _ => BrowserPreference.embedded,
+    };
+  }
+}

Diff for: lib/widgets/content.dart

@@ -1,7 +1,6 @@
 import 'dart:async';
 
 import 'package:flutter/cupertino.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
@@ -15,6 +14,7 @@ import '../model/avatar_url.dart';
 import '../model/binding.dart';
 import '../model/content.dart';
 import '../model/internal_link.dart';
+import '../model/settings.dart';
 import 'code_block.dart';
 import 'dialog.dart';
 import 'icons.dart';
@@ -1343,17 +1343,14 @@ void _launchUrl(BuildContext context, String urlString) async {
     return;
   }
 
+  final globalSettings = GlobalStoreWidget.of(context).globalSettings;
   bool launched = false;
   String? errorMessage;
   try {
     launched = await ZulipBinding.instance.launchUrl(url,
-      mode: switch (defaultTargetPlatform) {
-        // On iOS we prefer LaunchMode.externalApplication because (for
-        // HTTP URLs) LaunchMode.platformDefault uses SFSafariViewController,
-        // which gives an awkward UX as described here:
-        //  https://chat.zulip.org/#narrow/stream/48-mobile/topic/in-app.20browser/near/1169118
-        TargetPlatform.iOS => UrlLaunchMode.externalApplication,
-        _ => UrlLaunchMode.platformDefault,
+      mode: switch (globalSettings.effectiveBrowserPreference) {
+        BrowserPreference.embedded => UrlLaunchMode.inAppBrowserView,
+        BrowserPreference.external => UrlLaunchMode.externalApplication,
       });
   } on PlatformException catch (e) {
     errorMessage = e.message;

Diff for: test/model/settings_test.dart

@@ -0,0 +1,30 @@
+import 'package:checks/checks.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:zulip/model/settings.dart';
+
+import '../example_data.dart' as eg;
+import 'store_checks.dart';
+import 'store_test.dart';
+
+void main() {
+  group('effectiveBrowserPreference', () {
+    testAndroidIos('use non-default values', () {
+      final globalStore = eg.globalStore(globalSettings: eg.globalSettings(
+        browserPreference: BrowserPreference.external));
+      check(globalStore).globalSettings.effectiveBrowserPreference.equals(
+        BrowserPreference.external);
+    });
+
+    testAndroidIos('use default values by platform', () {
+      final globalStore = eg.globalStore();
+      if (defaultTargetPlatform == TargetPlatform.iOS) {
+        check(globalStore).globalSettings.effectiveBrowserPreference.equals(
+          BrowserPreference.external);
+      } else {
+        check(globalStore).globalSettings.effectiveBrowserPreference.equals(
+          BrowserPreference.embedded);
+      }
+    });
+  });
+}

Diff for: test/model/store_checks.dart

@@ -54,4 +54,5 @@ extension PerAccountStoreChecks on Subject<PerAccountStore> {
 
 extension GlobalSettingsDataChecks on Subject<GlobalSettingsData> {
   Subject<ThemeSetting> get themeSetting => has((x) => x.themeSetting, 'themeSetting');
+  Subject<BrowserPreference> get effectiveBrowserPreference => has((x) => x.effectiveBrowserPreference, 'effectiveBrowserPreference');
 }

Diff for: test/widgets/content_test.dart

@@ -9,6 +9,7 @@ import 'package:url_launcher/url_launcher.dart';
 import 'package:zulip/api/core.dart';
 import 'package:zulip/model/content.dart';
 import 'package:zulip/model/narrow.dart';
+import 'package:zulip/model/settings.dart';
 import 'package:zulip/model/store.dart';
 import 'package:zulip/widgets/content.dart';
 import 'package:zulip/widgets/icons.dart';
@@ -759,6 +760,18 @@ void main() {
         .single.equals((url: Uri.parse('https://example/'), mode: expectedLaunchMode));
     }, variant: const TargetPlatformVariant({TargetPlatform.android, TargetPlatform.iOS}));
 
+    testWidgets('override default with browser preference setting', (tester) async {
+      await testBinding.globalStore.updateGlobalSettings(
+        eg.globalSettings(
+          browserPreference: BrowserPreference.external).toCompanion(false));
+      await prepare(tester,
+          '<p><a href="https://example/">hello</a></p>');
+
+      await tapText(tester, find.text('hello'));
+      check(testBinding.takeLaunchUrlCalls())
+        .single.equals((url: Uri.parse('https://example/'), mode: LaunchMode.externalApplication));
+    }, variant: const TargetPlatformVariant({TargetPlatform.android, TargetPlatform.iOS}));
+
     testWidgets('multiple links in paragraph', (tester) async {
       const fontSize = kBaseFontSize;