Bug Fix: Adding back the plugin architecture logic for talawa app

lib/main.dart

@@ -1,5 +1,5 @@
+import 'dart:async';
 import 'dart:io';
-
 import 'package:firebase_core/firebase_core.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:flutter/foundation.dart';
@@ -20,7 +20,7 @@ import 'package:talawa/models/user/user_info.dart';
 import 'package:talawa/plugins/fetch_plugin_list.dart';
 import 'package:talawa/router.dart' as router;
 import 'package:talawa/utils/app_localization.dart';
-import 'package:talawa/view_model/base_view_model.dart';
+import 'package:talawa/view_model/base_view_model.dart';  
 import 'package:talawa/view_model/lang_view_model.dart';
 import 'package:talawa/view_model/theme_view_model.dart';
 import 'package:talawa/views/base_view.dart';
@@ -110,6 +110,7 @@ Future<void> main() async {
   await Hive.openBox<User>('currentUser');
   await Hive.openBox<OrgInfo>('currentOrg');
 
+  /// PluginBox stores the updated list of plugins being used by the current instance of talawa
   await Hive.openBox('pluginBox');
   await Hive.openBox('url');
 
@@ -175,19 +176,26 @@ class _MyAppState extends State<MyApp> {
 
   /// Initializing the mainScreen window to 1 to show the events by default after app in opened.
   late int mainScreenQuickActionindex = 0;
+  Timer? timer;
   @override
   void initState() {
+    // Timer.periodic(const Duration(seconds: 300), (timer) {
+    //   FetchPluginList();
+    // });
+    timer = Timer.periodic(
+      const Duration(seconds: 15),
+      (Timer t) => FetchPluginList(),
+    );
     // initState() is a method that is called once when the Stateful Widget
     // is inserted in the widget tree. We generally override this method if
     // we need to do some sort of initialization work like
     // registering a listener because, unlike build(), this method is called once.
     super.initState();
-
     initQuickActions();
 
     final urlBox = Hive.box('url');
     if (urlBox.get('url') != null) {
-      FetchPluginList();
+      // FetchPluginList();
     }
 
     fs.SystemChrome.setPreferredOrientations(
@@ -198,6 +206,12 @@ class _MyAppState extends State<MyApp> {
     );
   }
 
+  @override
+  void dispose() {
+    timer?.cancel();
+    super.dispose();
+  }
+
   /// It allows to manage and interact with the application’s home screen quick actions.
   ///
   /// **params**:
@@ -298,7 +312,7 @@ class DemoPageView extends StatelessWidget {
   const DemoPageView({required Key key}) : super(key: key);
   @override
   Widget build(BuildContext context) {
-    FetchPluginList();
+    // FetchPluginList();
     return BaseView<DemoViewModel>(
       builder: (context, model, child) => Scaffold(
         appBar: AppBar(

lib/plugins/fetch_plugin_list.dart

@@ -6,6 +6,8 @@ import 'package:talawa/locator.dart';
 class FetchPluginList {
   /// Constructor of the class.
   FetchPluginList() {
+    print(
+        "Fetching pligins =================================================================");
     fetchList();
   }
 

lib/views/main_screen.dart

@@ -1,52 +1,270 @@
-// ignore_for_file: talawa_api_doc
+// ignore_for_file: talawa_api_doc, avoid_dynamic_calls
 // ignore_for_file: talawa_good_doc_comments
-
+import 'dart:async';
 import 'package:flutter/material.dart';
+import 'package:hive/hive.dart';
 import 'package:talawa/models/mainscreen_navigation_args.dart';
+import 'package:talawa/plugins/fetch_plugin_list.dart';
+import 'package:talawa/utils/app_localization.dart';
 import 'package:talawa/view_model/main_screen_view_model.dart';
+import 'package:talawa/views/after_auth_screens/add_post_page.dart';
+import 'package:talawa/views/after_auth_screens/chat/chat_list_screen.dart';
+import 'package:talawa/views/after_auth_screens/events/explore_events.dart';
+import 'package:talawa/views/after_auth_screens/feed/organization_feed.dart';
+import 'package:talawa/views/after_auth_screens/profile/profile_page.dart';
 import 'package:talawa/views/base_view.dart';
 import 'package:talawa/widgets/custom_drawer.dart';
 
+/// list of navbarClasses
+late List<StatelessWidget> navBarClasses;
+
+/// list of navBarItems contains actual UI code of navbar items
+late List<BottomNavigationBarItem> navBarItems;
+
 class MainScreen extends StatefulWidget {
   const MainScreen({Key? key, required this.mainScreenArgs}) : super(key: key);
+  //final bool fromSignUp;
   final MainScreenArgs mainScreenArgs;
 
   @override
   State<MainScreen> createState() => _MainScreenState();
 }
 
 class _MainScreenState extends State<MainScreen> {
+  List<List<Object>> renderBottomNavBarPlugins(
+    List<BottomNavigationBarItem> navBarItems,
+    List<StatelessWidget> navBarClasses,
+    Map navNameClasses,
+    Map<String, Widget> navNameIcons,
+    BuildContext context,
+  ) {
+    //get list from hive
+    final Box box;
+    // ignore: prefer_typing_uninitialized_variables
+    var pluginList;
+    const bool res = false;
+    box = Hive.box('pluginBox');
+    // pluginList = box.get('plugins');
+
+    /// CAUTION : `pluginList` is currently filled with dummy data in order to make sure that
+    /// all features of talawa should be visible from the navbar.
+    /// following dummy data should be only used for developement purpose.
+    /// Adding dummy data enables to use Events,Posts,Chats features event if plugin documents for them is not created by the admin.
+    /// FOR PRODUCTION : please make this array empty to enable or test real plugin data from the server
+    pluginList ??= [
+      // if null then it will be replace with the following data
+      {
+        "_id": "63929c1915ad470d13c3bcb6",
+        "pluginInstallStatus": true,
+        "pluginName": "Events",
+        "pluginCreatedBy": " Mr. Siddhesh Bhupendra  Kukade",
+        "pluginDesc":
+            "Presenting the Events Plugin by Siddhesh Bhupendra Kuakde that implements the plugin features as a component here members can create and manage events and on top of it everything is controlled by the Organization Admins . Install and use right away.",
+        "installedOrgs": [
+          "62ccfccd3eb7fd2a30f41601",
+          "62ccfccd3eb7fd2a30f41601",
+          "<YOUR_ORG_ID_FOR_DEVELOPMENT>"
+        ]
+      },
+      {
+        "_id": "63929c1915ad470d13c3bcb6",
+        "pluginInstallStatus": true,
+        "pluginName": "Posts",
+        "pluginCreatedBy": "Mr.Johnathan Doe ",
+        "pluginDesc":
+            "Presenting the Donation plugin for the talawa app that enables members of the organization to  do One time or Reccurinng donations to an  organization",
+        "installedOrgs": [
+          "62ccfccd3eb7fd2a30f41601",
+          "62ccfccd3eb7fd2a30f41601",
+          "<YOUR_ORG_ID_FOR_DEVELOPMENT>"
+        ]
+      },
+      {
+        "_id": "62cfcf71824dc26e1fbeed46",
+        "pluginInstallStatus": true,
+        "pluginName": "Donation",
+        "pluginCreatedBy": "Kimia",
+        "pluginDesc":
+            "See all available organizations in entire world using this plugins",
+        "installedOrgs": [
+          "62ccfccd3eb7fd2a30f41601",
+          "<YOUR_ORG_ID_FOR_DEVELOPMENT>"
+        ]
+      },
+      {
+        "_id": "62cfcf71824dc26e1fbeed46",
+        "pluginInstallStatus": true,
+        "pluginName": "Chats",
+        "pluginCreatedBy": "Kimia",
+        "pluginDesc":
+            "See all available organizations in entire world using this plugins",
+        "installedOrgs": [
+          "62ccfccd3eb7fd2a30f41601",
+          "<YOUR_ORG_ID_FOR_DEVELOPMENT>"
+        ]
+      }
+    ];
+
+    /// Here we are dynamically adding BottomNavigationBarItems in navbar by mapping over the data received from the server.
+    // ignore: avoid_dynamic_calls
+    pluginList.forEach((plugin) => {
+          if (navNameClasses.containsKey(plugin["pluginName"] as String) &&
+              plugin["pluginInstallStatus"] as bool)
+            {
+              navBarItems.add(BottomNavigationBarItem(
+                icon: navNameIcons[plugin["pluginName"]] ??
+                    const Icon(Icons.home),
+                label: AppLocalizations.of(context)!
+                    .strictTranslate(plugin["pluginName"] as String),
+              )),
+              navBarClasses.add(navNameClasses[plugin["pluginName"]]["class"]
+                  as StatelessWidget),
+            },
+        });
+
+    /// updating the state to re-render the navbar widget.
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      /// This line causes the app to continiously check for plugins if they are updated
+      /// and it will automatically re-render the navbar with enables or disabled features
+      setState(() {});
+    });
+
+    return [navBarItems, navBarClasses];
+  }
+
   @override
   Widget build(BuildContext context) {
+    ///Features that are not meant to be implemented as plugins should be kept here.
+    navBarItems = [
+      BottomNavigationBarItem(
+        icon: const Icon(Icons.home),
+        label: AppLocalizations.of(context)!.strictTranslate('Home'),
+      ),
+      BottomNavigationBarItem(
+        icon: const Icon(Icons.account_circle),
+        label: AppLocalizations.of(context)!.strictTranslate('Profile'),
+      )
+    ];
+
     return BaseView<MainScreenViewModel>(
-      onModelReady: (model) {
-        model.initialise(
-          context,
-          fromSignUp: widget.mainScreenArgs.fromSignUp,
-          mainScreenIndex: widget.mainScreenArgs.mainScreenIndex,
-        );
-      },
+      onModelReady: (model) => model.initialise(
+        context,
+        fromSignUp: widget.mainScreenArgs.fromSignUp,
+        mainScreenIndex: widget.mainScreenArgs.mainScreenIndex,
+      ),
       builder: (context, model, child) {
-        // Checks for updates in plugins from the server.
-        // Will continously hit the server and fetch plugin information.
-        model.fetchAndAddPlugins(context);
+        /// `navNameIcon` Object maps Icons to proper features according to their names used in navbar.
+        /// CAUTION : Name of the feature in talwa app must match with the name that is provided by the admin.
+        final Map<String, Widget> navNameIcon = {
+          "Events": const Icon(Icons.event_note),
+          "Posts": const Icon(Icons.add_box),
+          "Profile": const Icon(Icons.account_circle),
+          "Chats": const Icon(Icons.chat_outlined),
+        };
 
+        /// `navNameClasses` Object maps the feature names with thier proper Icons and Widgets (named as `class`) used in navbar
+        /// CAUTION : Name of the feature in talwa app must match with the name that is provided by the admin.
+        final Map<dynamic, dynamic> navNameClasses = {
+          "Events": {
+            // "icon": Icons.event_note,
+            "class": ExploreEvents(
+              key: const Key('ExploreEvents'),
+              homeModel: model,
+            )
+          },
+          "Posts": {
+            "class": AddPost(
+              key: const Key('AddPost'),
+              drawerKey: MainScreenViewModel.scaffoldKey,
+            )
+          },
+          "Chats": {
+            "class": const ChatPage(
+              key: Key('Chats'),
+            ),
+          }
+        };
+
+        /// `navBarClasses` is the array that contains the Widgets to be rendered on the navbar
+        /// Features that should be implemented as plugins like Home, Profile,etc. should be kept here
+        /// When talawa app receives the plugins data is will dynamically render more components from the construtor.
+        navBarClasses = [
+          OrganizationFeed(key: const Key("HomeView"), homeModel: model),
+          ProfilePage(key: model.keySPEditProfile, homeModel: model),
+        ];
+        // ignore_for_file:  unused_local_variable
+        final res = renderBottomNavBarPlugins(
+            navBarItems, navBarClasses, navNameClasses, navNameIcon, context);
         return Scaffold(
           key: MainScreenViewModel.scaffoldKey,
-          drawer: CustomDrawer(
-            homeModel: model,
-            key: const Key("Custom Drawer"),
-          ),
+          drawer:
+              CustomDrawer(homeModel: model, key: const Key("Custom Drawer")),
           body: IndexedStack(
             index: model.currentPageIndex,
-            children: model.pages,
+            children: navBarClasses,
           ),
-          bottomNavigationBar: BottomNavigationBar(
-            type: BottomNavigationBarType.fixed,
-            currentIndex: model.currentPageIndex,
-            onTap: model.onTabTapped,
-            selectedItemColor: const Color(0xff34AD64),
-            items: model.navBarItems,
+          bottomNavigationBar: Stack(
+            children: [
+              SizedBox(
+                height: 50,
+                child: Row(
+                  children: [
+                    Expanded(
+                      child: Center(
+                        child: SizedBox(
+                          key: model.keyBNHome,
+                          height: 40,
+                          width: 40,
+                        ),
+                      ),
+                    ),
+                    Expanded(
+                      child: Center(
+                        child: SizedBox(
+                          key: model.keyBNEvents,
+                          height: 40,
+                          width: 40,
+                        ),
+                      ),
+                    ),
+                    Expanded(
+                      child: Center(
+                        child: SizedBox(
+                          key: model.keyBNPost,
+                          height: 40,
+                          width: 40,
+                        ),
+                      ),
+                    ),
+                    Expanded(
+                      child: Center(
+                        child: SizedBox(
+                          key: model.keyBNChat,
+                          height: 40,
+                          width: 40,
+                        ),
+                      ),
+                    ),
+                    Expanded(
+                      child: Center(
+                        child: SizedBox(
+                          key: model.keyBNProfile,
+                          height: 40,
+                          width: 40,
+                        ),
+                      ),
+                    ),
+                  ],
+                ),
+              ),
+              BottomNavigationBar(
+                type: BottomNavigationBarType.fixed,
+                currentIndex: model.currentPageIndex,
+                onTap: model.onTabTapped,
+                selectedItemColor: const Color(0xff34AD64),
+                items: navBarItems,
+              ),
+            ],
           ),
         );
       },