ideal case of private class code

lib/pages/new_space/new_space.dart

@@ -150,7 +150,10 @@ class NewSpaceController extends State<NewSpace> {
     try {
       final avatar = this.avatar;
       avatarUrl ??= avatar == null ? null : await client.uploadContent(avatar);
-
+      final classCode = await SpaceCodeUtil.generateSpaceCode(client);
+      if (classCode == null) {
+        return;
+      }
       final spaceId = await client.createRoom(
         // #Pangea
         // preset: publicGroup
@@ -164,7 +167,7 @@ class NewSpaceController extends State<NewSpace> {
         // roomAliasName: publicGroup
         //     ? nameController.text.trim().toLowerCase().replaceAll(' ', '_')
         //     : null,
-        roomAliasName: SpaceCodeUtil.generateSpaceCode(),
+        roomAliasName: classCode,
         // Pangea#
         name: nameController.text.trim(),
         topic: topicController.text.isEmpty ? null : topicController.text,
@@ -178,14 +181,21 @@ class NewSpaceController extends State<NewSpace> {
             : null,
         // Pangea#
         initialState: [
+          // #Pangea
+          ...initialState,
+          // Pangea#
           if (avatar != null)
             sdk.StateEvent(
               type: sdk.EventTypes.RoomAvatar,
               content: {'url': avatarUrl.toString()},
             ),
-          // #Pangea
-          ...initialState,
-          // Pangea#
+          sdk.StateEvent(
+            type: sdk.EventTypes.RoomJoinRules,
+            content: {
+              'join_rule': 'knock',
+              'access_code': classCode,
+            },
+          ),
         ],
       );
       // #Pangea

lib/pangea/constants/model_keys.dart

@@ -123,4 +123,8 @@ class ModelKey {
 
   static const String prevEventId = "prev_event_id";
   static const String prevLastUpdated = "prev_last_updated";
+
+  // room code
+  static const String joinRule = "join_rule";
+  static const String accessCode = "access_code";
 }

lib/pangea/controllers/class_controller.dart

@@ -1,7 +1,7 @@
 import 'dart:async';
+import 'dart:convert';
 import 'dart:developer';
 
-import 'package:collection/collection.dart';
 import 'package:fluffychat/pangea/constants/local.key.dart';
 import 'package:fluffychat/pangea/constants/pangea_event_types.dart';
 import 'package:fluffychat/pangea/controllers/pangea_controller.dart';
@@ -9,15 +9,15 @@ import 'package:fluffychat/pangea/extensions/client_extension/client_extension.d
 import 'package:fluffychat/pangea/extensions/pangea_room_extension/pangea_room_extension.dart';
 import 'package:fluffychat/pangea/models/space_model.dart';
 import 'package:fluffychat/pangea/utils/error_handler.dart';
+import 'package:fluffychat/pangea/utils/firebase_analytics.dart';
 import 'package:fluffychat/pangea/utils/space_code.dart';
+import 'package:fluffychat/widgets/matrix.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_gen/gen_l10n/l10n.dart';
 import 'package:future_loading_dialog/future_loading_dialog.dart';
 import 'package:matrix/matrix.dart';
 
-import '../../widgets/matrix.dart';
-import '../utils/firebase_analytics.dart';
 import 'base_controller.dart';
 
 class ClassController extends BaseController {
@@ -65,47 +65,56 @@ class ClassController extends BaseController {
   }
 
   Future<void> joinClasswithCode(BuildContext context, String classCode) async {
+    final client = Matrix.of(context).client;
     try {
-      final QueryPublicRoomsResponse queryPublicRoomsResponse =
-          await Matrix.of(context).client.queryPublicRooms(
-                limit: 1,
-                filter: PublicRoomQueryFilter(genericSearchTerm: classCode),
-              );
-
-      final PublicRoomsChunk? classChunk =
-          queryPublicRoomsResponse.chunk.firstWhereOrNull((element) {
-        return element.canonicalAlias?.replaceAll("#", "").split(":")[0] ==
-            classCode;
-      });
-
-      if (classChunk == null) {
+      final knockResponse = await client.httpClient.post(
+        Uri.parse(
+          '${client.homeserver}/_synapse/client/pangea/v1/knock_with_code',
+        ),
+        headers: {
+          'Content-Type': 'application/json',
+          'Authorization': 'Bearer ${client.accessToken}',
+        },
+        body: jsonEncode({'access_code': classCode}),
+      );
+      if (knockResponse.statusCode != 200) {
         SpaceCodeUtil.messageSnack(
           context,
           L10n.of(context)!.unableToFindClass,
         );
         return;
       }
-
+      final knockResult = jsonDecode(knockResponse.body);
+      final foundClasses = knockResult['rooms'];
+      if (!(foundClasses is List<String> && foundClasses.isNotEmpty)) {
+        SpaceCodeUtil.messageSnack(
+          context,
+          L10n.of(context)!.unableToFindClass,
+        );
+        return;
+      }
+      final chosenClassId = foundClasses.first;
+      await client.joinRoomById(chosenClassId);
       if (_pangeaController.matrixState.client.rooms
-          .any((room) => room.id == classChunk.roomId)) {
-        setActiveSpaceIdInChatListController(classChunk.roomId);
+          .any((room) => room.id == chosenClassId)) {
+        setActiveSpaceIdInChatListController(chosenClassId);
         SpaceCodeUtil.messageSnack(context, L10n.of(context)!.alreadyInClass);
         return;
       }
 
-      await _pangeaController.matrixState.client.joinRoom(classChunk.roomId);
+      await _pangeaController.matrixState.client.joinRoom(chosenClassId);
 
-      if (_pangeaController.matrixState.client.getRoomById(classChunk.roomId) ==
+      if (_pangeaController.matrixState.client.getRoomById(chosenClassId) ==
           null) {
         await _pangeaController.matrixState.client.waitForRoomInSync(
-          classChunk.roomId,
+          chosenClassId,
           join: true,
         );
       }
 
       // If the room is full, leave
       final room =
-          _pangeaController.matrixState.client.getRoomById(classChunk.roomId);
+          _pangeaController.matrixState.client.getRoomById(chosenClassId);
       if (room == null) {
         return;
       }
@@ -121,12 +130,12 @@ class ClassController extends BaseController {
         return;
       }
 
-      setActiveSpaceIdInChatListController(classChunk.roomId);
+      setActiveSpaceIdInChatListController(chosenClassId);
 
       // add the user's analytics room to this joined space
       // so their teachers can join them via the space hierarchy
       final Room? joinedSpace =
-          _pangeaController.matrixState.client.getRoomById(classChunk.roomId);
+          _pangeaController.matrixState.client.getRoomById(chosenClassId);
 
       // when possible, add user's analytics room the to space they joined
       joinedSpace?.addAnalyticsRoomsToSpace();

lib/pangea/extensions/pangea_room_extension/space_settings_extension.dart

@@ -15,8 +15,14 @@ extension SpaceRoomExtension on Room {
       }
       return "Not in a class!";
     }
-
-    return canonicalAlias.replaceAll(":$domainString", "").replaceAll("#", "");
+    final roomJoinRules = getState(EventTypes.RoomJoinRules, "");
+    if (roomJoinRules != null) {
+      final accessCode = roomJoinRules.content.tryGet(ModelKey.accessCode);
+      if (accessCode is String) {
+        return accessCode;
+      }
+    }
+    return "No class code!";
   }
 
   void _checkClass() {

lib/pangea/utils/space_code.dart

@@ -1,10 +1,10 @@
-import 'dart:math';
+import 'dart:convert';
 
 import 'package:adaptive_dialog/adaptive_dialog.dart';
+import 'package:fluffychat/pangea/controllers/pangea_controller.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_gen/gen_l10n/l10n.dart';
-
-import '../controllers/pangea_controller.dart';
+import 'package:matrix/matrix.dart';
 
 class SpaceCodeUtil {
   static const codeLength = 6;
@@ -13,11 +13,25 @@ class SpaceCodeUtil {
     return spacecode == null || spacecode.length > 4;
   }
 
-  static String generateSpaceCode() {
-    final r = Random();
-    const chars = 'AaBbCcDdEeFfGgHhiJjKkLMmNnoPpQqRrSsTtUuVvWwXxYyZz1234567890';
-    return List.generate(codeLength, (index) => chars[r.nextInt(chars.length)])
-        .join();
+  static Future<String?> generateSpaceCode(Client client) async {
+    final response = await client.httpClient.get(
+      Uri.parse(
+        '${client.homeserver}/_synapse/client/pangea/v1/request_room_code',
+      ),
+      headers: {
+        'Content-Type': 'application/json',
+        'Authorization': 'Bearer ${client.accessToken}',
+      },
+    );
+    if (response.statusCode != 200) {
+      return null;
+    }
+    final roomCodeResult = jsonDecode(response.body);
+    if (roomCodeResult['access_code'] is String) {
+      return roomCodeResult['access_code'] as String;
+    } else {
+      throw Exception('Invalid response, access_code not found $response');
+    }
   }
 
   static Future<void> joinWithSpaceCodeDialog(