TF-340 Debouncing when open the mailbox to prevent too much pressure on Back-end request

core/lib/presentation/state/success.dart

@@ -4,6 +4,8 @@ abstract class Success with EquatableMixin {}
 
 abstract class ViewState extends Success {}
 
+abstract class ViewEvent extends Success {}
+
 class UIState extends ViewState {
   static final idle = UIState();
 

lib/features/mailbox/presentation/mailbox_controller.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:core/core.dart';
 import 'package:dartz/dartz.dart';
 import 'package:flutter/material.dart';
@@ -8,6 +10,7 @@ import 'package:jmap_dart_client/jmap/core/id.dart';
 import 'package:jmap_dart_client/jmap/core/state.dart' as jmapState;
 import 'package:jmap_dart_client/jmap/mail/mailbox/mailbox.dart';
 import 'package:model/model.dart';
+import 'package:rxdart/transformers.dart';
 import 'package:tmail_ui_user/features/base/base_mailbox_controller.dart';
 import 'package:tmail_ui_user/features/caching/caching_manager.dart';
 import 'package:tmail_ui_user/features/composer/domain/state/save_email_as_drafts_state.dart';
@@ -31,6 +34,7 @@ import 'package:tmail_ui_user/features/mailbox/domain/usecases/search_mailbox_in
 import 'package:tmail_ui_user/features/mailbox/presentation/model/mailbox_actions.dart';
 import 'package:tmail_ui_user/features/mailbox/presentation/model/mailbox_node.dart';
 import 'package:tmail_ui_user/features/mailbox/presentation/model/mailbox_tree.dart';
+import 'package:tmail_ui_user/features/mailbox/presentation/model/open_mailbox_view_event.dart';
 import 'package:tmail_ui_user/features/mailbox_creator/domain/model/verification/duplicate_name_validator.dart';
 import 'package:tmail_ui_user/features/mailbox_creator/domain/model/verification/empty_name_validator.dart';
 import 'package:tmail_ui_user/features/mailbox_creator/domain/model/verification/special_character_validator.dart';
@@ -73,6 +77,8 @@ class MailboxController extends BaseMailboxController {
   final searchQuery = SearchQuery.initial().obs;
   final currentSelectMode = SelectMode.INACTIVE.obs;
 
+  final _openMailboxEventController = StreamController<OpenMailboxViewEvent>();
+
   List<PresentationMailbox> allMailboxes = <PresentationMailbox>[];
   TextEditingController searchInputController = TextEditingController();
   FocusNode searchFocus = FocusNode();
@@ -123,6 +129,10 @@ class MailboxController extends BaseMailboxController {
         }
       });
     });
+
+    _openMailboxEventController.stream.throttleTime(Duration(milliseconds: 800)).listen((event) {
+      _handleOpenMailbox(event.buildContext, event.presentationMailbox);
+    });
   }
 
   @override
@@ -246,9 +256,9 @@ class MailboxController extends BaseMailboxController {
     }
   }
 
-  void openMailbox(
-      BuildContext context,
-      PresentationMailbox presentationMailboxSelected
+  void _handleOpenMailbox(
+    BuildContext context,
+    PresentationMailbox presentationMailboxSelected
   ) {
     FocusScope.of(context).unfocus();
 
@@ -260,6 +270,13 @@ class MailboxController extends BaseMailboxController {
     }
   }
 
+  void openMailbox(
+      BuildContext context,
+      PresentationMailbox presentationMailboxSelected
+  ) {
+    _openMailboxEventController.add(OpenMailboxViewEvent(context, presentationMailboxSelected));
+  }
+
   void _deleteCredential() async {
     await _deleteCredentialInteractor.execute();
   }
@@ -594,4 +611,10 @@ class MailboxController extends BaseMailboxController {
     _clearAllCache();
     pushAndPopAll(AppRoutes.LOGIN);
   }
+
+  @override
+  void dispose() {
+    _openMailboxEventController.close();
+    super.dispose();
+  }
 }

lib/features/mailbox/presentation/model/open_mailbox_view_event.dart

@@ -0,0 +1,13 @@
+import 'package:core/presentation/state/success.dart';
+import 'package:flutter/widgets.dart';
+import 'package:model/mailbox/presentation_mailbox.dart';
+
+class OpenMailboxViewEvent extends ViewEvent {
+  final BuildContext buildContext;
+  final PresentationMailbox presentationMailbox;
+
+  OpenMailboxViewEvent(this.buildContext, this.presentationMailbox);
+
+  @override
+  List<Object?> get props => [buildContext, presentationMailbox];
+}

pubspec.yaml

@@ -135,6 +135,8 @@ dependencies:
 
   pointer_interceptor: 0.9.1
 
+  rxdart: 0.27.3
+
 dev_dependencies:
   flutter_test:
     sdk: flutter