feat: show amount of unread messages

packages/flutter_community_chat_firebase/lib/service/firebase_chat_service.dart

@@ -29,6 +29,24 @@ class FirebaseChatService implements ChatService {
     _options = options ?? const FirebaseChatOptions();
   }
 
+  StreamSubscription<DocumentSnapshot> _addUnreadChatSubscription(
+    String chatId,
+    String userId,
+    Function(int) onUnreadChatsUpdated,
+  ) {
+    var snapshots = _db
+        .collection(_options.usersCollectionName)
+        .doc(userId)
+        .collection('chats')
+        .doc(chatId)
+        .snapshots();
+
+    return snapshots.listen((snapshot) {
+      var data = snapshot.data();
+      onUnreadChatsUpdated(data?['amount_unread_messages'] ?? 0);
+    });
+  }
+
   StreamSubscription<QuerySnapshot> _addChatSubscription(
     List<String> chatIds,
     Function(List<ChatModel>) onReceivedChats,
@@ -79,6 +97,8 @@ class FirebaseChatService implements ChatService {
             );
           }
         }
+        ChatModel? chatModel;
+
         if (chatData.personal) {
           var otherUserId = List<String>.from(chatData.users).firstWhere(
             (element) => element != currentUser?.id,
@@ -86,8 +106,7 @@ class FirebaseChatService implements ChatService {
           var otherUser = await _userService.getUser(otherUserId);
 
           if (otherUser != null) {
-            chats.add(
+            chatModel = PersonalChatModel(
-              PersonalChatModel(
               id: chatDoc.id,
               user: otherUser,
               lastMessage: messages.isNotEmpty ? messages.last : null,
@@ -97,7 +116,6 @@ class FirebaseChatService implements ChatService {
                   : DateTime.fromMillisecondsSinceEpoch(
                       chatData.lastUsed!.millisecondsSinceEpoch,
                     ),
-              ),
             );
           }
         } else {
@@ -109,8 +127,7 @@ class FirebaseChatService implements ChatService {
               users.add(user);
             }
           }
-          chats.add(
+          chatModel = GroupChatModel(
-            GroupChatModel(
             id: chatDoc.id,
             title: chatData.title ?? '',
             imageUrl: chatData.imageUrl ?? '',
@@ -122,9 +139,27 @@ class FirebaseChatService implements ChatService {
                 : DateTime.fromMillisecondsSinceEpoch(
                     chatData.lastUsed!.millisecondsSinceEpoch,
                   ),
-            ),
           );
         }
+        if (chatModel != null) {
+          _addUnreadChatSubscription(chatModel.id ?? '', currentUser?.id ?? '',
+              (unreadMessages) {
+            // the chatmodel should be updated to reflect the amount of unread messages
+            if (chatModel is PersonalChatModel) {
+              chatModel = (chatModel as PersonalChatModel)
+                  .copyWith(unreadMessages: unreadMessages);
+            } else if (chatModel is GroupChatModel) {
+              chatModel = (chatModel as GroupChatModel)
+                  .copyWith(unreadMessages: unreadMessages);
+            }
+
+            chats = chats
+                .map((chat) => chat.id == chatModel?.id ? chatModel! : chat)
+                .toList();
+            onReceivedChats(chats);
+          });
+          chats.add(chatModel!);
+        }
       }
       onReceivedChats(chats);
     });

packages/flutter_community_chat_interface/lib/src/model/chat.dart

@@ -8,12 +8,14 @@ abstract class ChatModel {
   ChatModel({
     this.id,
     this.messages = const [],
+    this.unreadMessages,
     this.lastUsed,
     this.lastMessage,
   });
 
   String? id;
   List<ChatMessageModel>? messages;
+  int? unreadMessages;
   DateTime? lastUsed;
   ChatMessageModel? lastMessage;
 }

packages/flutter_community_chat_interface/lib/src/model/group_chat.dart

@@ -13,9 +13,31 @@ class GroupChatModel extends ChatModel {
     super.messages,
     super.lastUsed,
     super.lastMessage,
+    super.unreadMessages,
   });
 
   final String title;
   final String imageUrl;
   final List<ChatUserModel> users;
+
+  GroupChatModel copyWith({
+    String? id,
+    List<ChatMessageModel>? messages,
+    int? unreadMessages,
+    DateTime? lastUsed,
+    ChatMessageModel? lastMessage,
+    String? title,
+    String? imageUrl,
+    List<ChatUserModel>? users,
+  }) =>
+      GroupChatModel(
+        id: id ?? this.id,
+        messages: messages ?? this.messages,
+        unreadMessages: unreadMessages ?? this.unreadMessages,
+        lastUsed: lastUsed ?? this.lastUsed,
+        lastMessage: lastMessage ?? this.lastMessage,
+        title: title ?? this.title,
+        imageUrl: imageUrl ?? this.imageUrl,
+        users: users ?? this.users,
+      );
 }

packages/flutter_community_chat_interface/lib/src/model/personal_chat.dart

@@ -9,9 +9,27 @@ class PersonalChatModel extends ChatModel {
     required this.user,
     super.id,
     super.messages,
+    super.unreadMessages,
     super.lastUsed,
     super.lastMessage,
   });
 
   final ChatUserModel user;
+
+  PersonalChatModel copyWith({
+    String? id,
+    List<ChatMessageModel>? messages,
+    int? unreadMessages,
+    DateTime? lastUsed,
+    ChatMessageModel? lastMessage,
+    ChatUserModel? user,
+  }) =>
+      PersonalChatModel(
+        id: id ?? this.id,
+        messages: messages ?? this.messages,
+        unreadMessages: unreadMessages ?? this.unreadMessages,
+        lastUsed: lastUsed ?? this.lastUsed,
+        lastMessage: lastMessage ?? this.lastMessage,
+        user: user ?? this.user,
+      );
 }

packages/flutter_community_chat_view/lib/src/components/chat_row.dart

@@ -7,12 +7,14 @@ import 'package:flutter/material.dart';
 class ChatRow extends StatelessWidget {
   const ChatRow({
     required this.title,
+    this.unreadMessages = 0,
     this.lastUsed,
     this.subTitle,
     this.avatar,
     super.key,
   });
   final String title;
+  final int unreadMessages;
   final Widget? avatar;
   final String? subTitle;
   final String? lastUsed;
@@ -35,9 +37,11 @@ class ChatRow extends StatelessWidget {
                     title,
                     maxLines: 1,
                     overflow: TextOverflow.ellipsis,
-                    style: const TextStyle(
+                    style: TextStyle(
                       fontSize: 18,
-                      fontWeight: FontWeight.w500,
+                      fontWeight: unreadMessages > 0
+                          ? FontWeight.w600
+                          : FontWeight.w400,
                     ),
                   ),
                   if (subTitle != null)
@@ -45,8 +49,11 @@ class ChatRow extends StatelessWidget {
                       padding: const EdgeInsets.only(top: 3.0),
                       child: Text(
                         subTitle!,
-                        style: const TextStyle(
+                        style: TextStyle(
                           fontSize: 16,
+                          fontWeight: unreadMessages > 0
+                              ? FontWeight.w600
+                              : FontWeight.w400,
                         ),
                         overflow: TextOverflow.ellipsis,
                         maxLines: 1,
@@ -56,6 +63,10 @@ class ChatRow extends StatelessWidget {
               ),
             ),
           ),
+          Column(
+            mainAxisAlignment: MainAxisAlignment.start,
+            crossAxisAlignment: CrossAxisAlignment.end,
+            children: [
               Text(
                 lastUsed ?? '',
                 style: const TextStyle(
@@ -63,6 +74,29 @@ class ChatRow extends StatelessWidget {
                   fontSize: 14,
                 ),
               ),
+              if (unreadMessages > 0) ...[
+                Padding(
+                  padding: const EdgeInsets.only(top: 4.0),
+                  child: Container(
+                    width: 20,
+                    height: 20,
+                    decoration: BoxDecoration(
+                      color: Theme.of(context).colorScheme.primary,
+                      shape: BoxShape.circle,
+                    ),
+                    child: Center(
+                      child: Text(
+                        unreadMessages.toString(),
+                        style: const TextStyle(
+                          fontSize: 14,
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              ],
+            ],
+          ),
         ],
       );
 }

packages/flutter_community_chat_view/lib/src/screens/chat_screen.dart

@@ -99,6 +99,8 @@ class _ChatScreenState extends State<ChatScreen> {
                               child: widget.options.chatRowContainerBuilder(
                                 (chat is PersonalChatModel)
                                     ? ChatRow(
+                                        unreadMessages:
+                                            chat.unreadMessages ?? 0,
                                         avatar:
                                             widget.options.userAvatarBuilder(
                                           chat.user,
@@ -122,6 +124,8 @@ class _ChatScreenState extends State<ChatScreen> {
                                       )
                                     : ChatRow(
                                         title: (chat as GroupChatModel).title,
+                                        unreadMessages:
+                                            chat.unreadMessages ?? 0,
                                         subTitle: chat.lastMessage != null
                                             ? chat.lastMessage
                                                     is ChatTextMessageModel