android, desktop: marking chat read fix (#5658)

* android, desktop: marking chat read fix

* comments

apps/ios/SimpleXChat/ChatTypes.swift

@@ -1612,6 +1612,7 @@ public struct ChatStats: Decodable, Hashable {
     // actual only via getChats() and getChat(.initial), otherwise, zero
     public var reportsCount: Int = 0
     public var minUnreadItemId: Int64 = 0
+    // actual only via getChats(), otherwise, false
     public var unreadChat: Bool = false
 }
 

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/model/ChatModel.kt

@@ -1233,10 +1233,11 @@ data class Chat(
   @Serializable
   data class ChatStats(
     val unreadCount: Int = 0,
-    // actual only via getChats() and getChat(.initial), otherwise, zero
     val unreadMentions: Int = 0,
+    // actual only via getChats() and getChat(.initial), otherwise, zero
     val reportsCount: Int = 0,
     val minUnreadItemId: Long = 0,
+    // actual only via getChats(), otherwise, false
     val unreadChat: Boolean = false
   )
 

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/chat/ChatItemsLoader.kt

@@ -54,11 +54,13 @@ suspend fun processLoadedChat(
       if (contentTag == null) {
         // update main chats, not content tagged
         withChats {
-          if (getChat(chat.id) == null) {
+          val oldChat = getChat(chat.id)
+          if (oldChat == null) {
             addChat(chat)
           } else {
             updateChatInfo(chat.remoteHostId, chat.chatInfo)
-            updateChatStats(chat.remoteHostId, chat.id, chat.chatStats)
+            // unreadChat is currently not actual in getChat query (always false)
+            updateChatStats(chat.remoteHostId, chat.id, chat.chatStats.copy(unreadChat = oldChat.chatStats.unreadChat))
           }
         }
       }