feature(@desktop/chat): support jumping to search result message that is not currently loaded in memory

Feature added. Firstly we check if the searched message is already displayed and if yes simply jump
to it, if not then we are loading new 20 messages in the past using cursor and check if the
searched message's id is among those received messages. We do that in a loop till we find the
message we are searching for.

Fixes: #3005

src/app/chat/views/messages.nim

@@ -32,6 +32,8 @@ QtObject:
     unreadMessageCnt: int
     unreadDirectMessagesAndMentionsCount: int
     channelOpenTime*: Table[string, int64]
+    searchedMessageId: string
+    loadingHistoryMessages: bool
 
   proc setup(self: MessageView) = self.QAbstractListModel.setup
   proc delete*(self: MessageView) =
@@ -57,9 +59,32 @@ QtObject:
     result.unreadMessageCnt = 0
     result.searchResultMessageModel = newMessageListProxyModel(status)
     result.unreadDirectMessagesAndMentionsCount = 0
+    result.loadingHistoryMessages = false
     result.setup
 
-  # proc getMessageListIndexById(self: MessageView, id: string): int
+  #################################################
+  # Forward declaration section
+  #################################################
+  proc checkIfSearchedMessageIsLoaded(self: MessageView)
+
+  #################################################
+  # Properties
+  #################################################
+  proc loadingHistoryMessagesChanged*(self: MessageView) {.signal.}
+
+  proc setLoadingHistoryMessages*(self: MessageView, value: bool) =
+    if (value == self.loadingHistoryMessages):
+      return
+
+    self.loadingHistoryMessages = value
+    self.loadingHistoryMessagesChanged()
+
+  proc getLoadingHistoryMessages*(self: MessageView): QVariant {.slot.} =
+    return newQVariant(self.loadingHistoryMessages)
+
+  QtProperty[QVariant] loadingHistoryMessages:
+    read = getLoadingHistoryMessages
+    notify = loadingHistoryMessagesChanged
 
   proc replaceMentionsWithPubKeys(self: MessageView, mentions: seq[string], contacts: seq[Profile], message: string, predicate: proc (contact: Profile): string): string =
     var updatedMessage = message
@@ -263,11 +288,16 @@ QtObject:
 
   proc loadMoreMessages*(self: MessageView) {.slot.} =
     let channelId = self.channelView.activeChannel.id
+
+    self.setLoadingHistoryMessages(true)
     self.status.chat.loadMoreMessagesForChannel(channelId)
 
   proc onMessagesLoaded*(self: MessageView, messages: var seq[Message]) =
     self.pushMessages(messages)
     self.messagesLoaded();
+    self.setLoadingHistoryMessages(false)
+
+    self.checkIfSearchedMessageIsLoaded()
     
   proc loadingMessagesChanged*(self: MessageView, value: bool) {.signal.}
 
@@ -436,3 +466,24 @@ QtObject:
   proc onSearchMessagesLoaded*(self: MessageView, messages: seq[Message]) =
     self.searchResultMessageModel.setFilteredMessages(messages)
 
+  proc isMessageDisplayed*(self: MessageView, messageId: string): bool {.slot.} =
+    let chatId = self.channelView.activeChannel.id
+    var message = self.messageList[chatId].getMessageById(messageId)
+
+    return message.id != ""
+
+  proc loadMessagesTillMessageWithIdIsLoaded*(self: MessageView, messageId: string) {.slot.} =
+    self.searchedMessageId = messageId
+    self.loadMoreMessages()
+
+  proc searchedMessageLoaded*(self: MessageView, messageId: string) {.signal.}
+
+  proc checkIfSearchedMessageIsLoaded(self: MessageView) =
+    if (self.searchedMessageId.len == 0):
+      return
+
+    if (self.isMessageDisplayed(self.searchedMessageId)):
+      self.searchedMessageLoaded(self.searchedMessageId)
+      self.searchedMessageId = ""
+    else:
+      self.loadMoreMessages()

ui/app/AppLayouts/Chat/ChatColumn.qml

@@ -585,6 +585,10 @@ Item {
         Connections {
             target: chatsModel.messageView
 
+            onSearchedMessageLoaded: {
+                positionAtMessage(messageId)
+            }
+
             onMessageNotificationPushed: function(chatId, msg, contentType, chatType, timestamp, identicon, username, hasMention, isAddedContact, channelName) {
                 if (appSettings.notificationSetting == Constants.notifyAllMessages ||
                         (appSettings.notificationSetting == Constants.notifyJustMentions && hasMention)) {

ui/app/AppLayouts/Chat/ChatColumn/ChatMessages.qml

@@ -23,7 +23,6 @@ Item {
 
     property var messageContextMenuInst
     property var messageList: MessagesData {}
-    property bool loadingMessages: false
     property real scrollY: chatLogView.visibleArea.yPosition * chatLogView.contentHeight
     property int newMessages: 0
     property int countOnStartUp: 0
@@ -180,9 +179,6 @@ Item {
 
         Connections {
             target: chatsModel.messageView
-            onMessagesLoaded: {
-                loadingMessages = false;
-            }
 
             onSendingMessage: {
                 chatLogView.scrollToBottom(true)
@@ -227,8 +223,9 @@ Item {
         }
 
         property var loadMsgs : Backpressure.oneInTime(chatLogView, 500, function() {
-            if(loadingMessages) return;
+            if(chatsModel.messageView.loadingHistoryMessages)
-            loadingMessages = true;
+                return
+
             chatsModel.messageView.loadMoreMessages();
         });
 

ui/app/AppLayouts/Chat/components/SearchPopup.qml

@@ -212,7 +212,10 @@ Popup {
 
                         popup.close()
 
-                        positionAtMessage(model.messageId)
+                        if(chatsModel.messageView.isMessageDisplayed(model.messageId))
+                            positionAtMessage(model.messageId)
+                        else
+                            chatsModel.messageView.loadMessagesTillMessageWithIdIsLoaded(model.messageId)
                     }
 
                     prevMessageIndex: -1