feat: introduce "fetch more messages" button to request old messages

Closes #149

src/app/chat/event_handling.nim

@@ -78,7 +78,7 @@ proc handleMailserverEvents(self: ChatController) =
 
   self.status.events.on("mailserverAvailable") do(e:Args):
     let mailserverTopics = self.status.mailservers.getMailserverTopics()
-    var fromValue: int64 = times.toUnix(times.getTime()) - 86400
+    var fromValue = times.toUnix(times.getTime()) - 86400 # today - 24 hours
 
     if mailserverTopics.len > 0:
        fromValue = min(mailserverTopics.map(topic => topic.lastRequest))

src/app/chat/view.nim

@@ -1,6 +1,8 @@
 import NimQml, Tables, json, sequtils, chronicles, times, re, sugar, strutils, os, strformat
 import ../../status/status
+import ../../status/mailservers
 import ../../status/libstatus/accounts/constants
+import ../../status/libstatus/mailservers as status_mailservers
 import ../../status/accounts as status_accounts
 import ../../status/chat as status_chat
 import ../../status/messages as status_messages
@@ -35,6 +37,7 @@ QtObject:
       channelOpenTime*: Table[string, int64]
       connected: bool
       unreadMessageCnt: int
+      oldestMessageTimestamp: int64
 
   proc setup(self: ChatsView) = self.QAbstractListModel.setup
 
@@ -62,6 +65,27 @@ QtObject:
     result.pubKey = ""
     result.setup()
 
+  proc oldestMessageTimestampChanged*(self: ChatsView) {.signal.}
+
+  proc getOldestMessageTimestamp*(self: ChatsView): QVariant {.slot.}  =
+    newQVariant($self.oldestMessageTimestamp)
+
+  QtProperty[QVariant] oldestMsgTimestamp:
+    read = getOldestMessageTimestamp
+    notify = oldestMessageTimestampChanged
+
+  proc setLastMessageTimestamp(self: ChatsView, force = false) = 
+    if self.status.chat.lastMessageTimestamps.hasKey(self.activeChannel.id):
+      if force or self.status.chat.lastMessageTimestamps[self.activeChannel.id] <= self.oldestMessageTimestamp:
+        self.oldestMessageTimestamp = self.status.chat.lastMessageTimestamps[self.activeChannel.id]
+    else:
+      let topics = self.status.mailservers.getMailserverTopicsByChatId(self.activeChannel.id)
+      if topics.len > 0:
+        self.oldestMessageTimestamp = topics[0].lastRequest
+      else:
+        self.oldestMessageTimestamp = times.toUnix(times.getTime())
+    self.oldestMessageTimestampChanged()
+
   proc addStickerPackToList*(self: ChatsView, stickerPack: StickerPack, isInstalled, isBought: bool) =
     self.stickerPacks.addStickerPackToList(stickerPack, newStickerList(stickerPack.stickers), isInstalled, isBought)
   
@@ -206,6 +230,7 @@ QtObject:
     self.status.chat.setActiveChannel(selectedChannel.id)
     discard self.status.chat.markAllChannelMessagesRead(selectedChannel.id)
     self.currentSuggestions.setNewData(self.status.contacts.getContacts())
+    self.setLastMessageTimestamp(true)
     self.activeChannelChanged()
 
   proc getActiveChannelIdx(self: ChatsView): QVariant {.slot.} =
@@ -237,6 +262,7 @@ QtObject:
     self.activeChannel.setChatItem(self.chats.getChannel(self.chats.chats.findIndexById(channel)))
     discard self.status.chat.markAllChannelMessagesRead(self.activeChannel.id)
     self.currentSuggestions.setNewData(self.status.contacts.getContacts())
+    self.setLastMessageTimestamp(true)
     self.activeChannelChanged()
 
   proc getActiveChannel*(self: ChatsView): QVariant {.slot.} =
@@ -373,6 +399,8 @@ QtObject:
     trace "Loading more messages", chaId = self.activeChannel.id
     self.status.chat.chatMessages(self.activeChannel.id, false)
     self.status.chat.chatReactions(self.activeChannel.id, false)
+    if self.status.chat.msgCursor[self.activeChannel.id] == "":
+      self.setLastMessageTimestamp()
     self.messagesLoaded();
 
   proc loadMoreMessagesWithIndex*(self: ChatsView, channelIndex: int) {.slot.} =
@@ -382,6 +410,16 @@ QtObject:
     trace "Loading more messages", chaId = selectedChannel.id
     self.status.chat.chatMessages(selectedChannel.id, false)
     self.status.chat.chatReactions(selectedChannel.id, false)
+    self.setLastMessageTimestamp()
+    self.messagesLoaded();
+
+  proc requestMoreMessages*(self: ChatsView) {.slot.} =
+    let topics = self.status.mailservers.getMailserverTopicsByChatId(self.activeChannel.id).map(topic => topic.topic)
+    let currentOldestMessageTimestamp = self.oldestMessageTimestamp
+    self.oldestMessageTimestamp = self.oldestMessageTimestamp - 86400
+
+    self.status.mailservers.requestMessages(topics, self.oldestMessageTimestamp, currentOldestMessageTimestamp, true)
+    self.oldestMessageTimestampChanged()
     self.messagesLoaded();
 
   proc leaveChatByIndex*(self: ChatsView, channelIndex: int) {.slot.} =

src/app/chat/views/message_list.nim

@@ -52,6 +52,10 @@ QtObject:
 
   include message_format
 
+  proc fetchMoreMessagesButton(self: ChatMessageList): Message =
+    result = Message()
+    result.contentType = ContentType.FetchMoreMessagesButton;
+
   proc chatIdentifier(self: ChatMessageList, chatId:string): Message =
     result = Message()
     result.contentType = ContentType.ChatIdentifier;
@@ -59,7 +63,7 @@ QtObject:
 
   proc newChatMessageList*(chatId: string, status: Status): ChatMessageList =
     new(result, delete)
-    result.messages = @[result.chatIdentifier(chatId)]
+    result.messages = @[result.chatIdentifier(chatId), result.fetchMoreMessagesButton()]
     result.messageIndex = initTable[string, int]()
     result.timedoutMessages = initHashSet[string]()
     result.status = status

src/status/chat.nim

@@ -1,4 +1,4 @@
-import eventemitter, json, strutils, sequtils, tables, chronicles, sugar
+import eventemitter, json, strutils, sequtils, tables, chronicles, sugar, times
 import libstatus/contracts as status_contracts
 import libstatus/chat as status_chat
 import libstatus/mailservers as status_mailservers
@@ -51,6 +51,7 @@ type
     availableStickerPacks*: Table[int, StickerPack]
     installedStickerPacks*: Table[int, StickerPack]
     purchasedStickerPacks*: seq[int]
+    lastMessageTimestamps*: Table[string, int64]
     
   MessageArgs* = ref object of Args
     id*: string
@@ -69,6 +70,7 @@ proc newChatModel*(events: EventEmitter): ChatModel =
   result.availableStickerPacks = initTable[int, StickerPack]()
   result.installedStickerPacks = initTable[int, StickerPack]()
   result.purchasedStickerPacks = @[]
+  result.lastMessageTimestamps = initTable[string, int64]()
 
 
 proc delete*(self: ChatModel) =
@@ -79,6 +81,15 @@ proc update*(self: ChatModel, chats: seq[Chat], messages: seq[Message], emojiRea
     if chat.isActive:
       self.channels[chat.id] = chat
 
+  for message in messages:
+    let chatId = message.chatId
+    let ts = times.convert(Milliseconds, Seconds, message.whisperTimestamp.parseInt())
+    if not self.lastMessageTimestamps.hasKey(chatId):
+      self.lastMessageTimestamps[chatId] = ts
+    else:
+      if self.lastMessageTimestamps[chatId] > ts:
+        self.lastMessageTimestamps[chatId] = ts
+      
   self.events.emit("chatUpdate", ChatUpdateArgs(messages: messages, chats: chats, contacts: @[], emojiReactions: emojiReactions))
 
 proc hasChannel*(self: ChatModel, chatId: string): bool =
@@ -293,6 +304,12 @@ proc chatMessages*(self: ChatModel, chatId: string, initialLoad:bool = true) =
 
   let messageTuple = status_chat.chatMessages(chatId, self.msgCursor[chatId])
   self.msgCursor[chatId] = messageTuple[0];
+
+  if messageTuple[1].len > 0:
+    let lastMsgIndex = messageTuple[1].len - 1
+    let ts = times.convert(Milliseconds, Seconds, messageTuple[1][lastMsgIndex].whisperTimestamp.parseInt())
+    self.lastMessageTimestamps[chatId] = ts
+
   self.events.emit("messagesLoaded", MsgsLoadedArgs(messages: messageTuple[1]))
 
 proc chatReactions*(self: ChatModel, chatId: string, initialLoad:bool = true) =

src/status/chat/message.nim

@@ -1,6 +1,7 @@
 import strformat
 
 type ContentType* {.pure.} = enum
+  FetchMoreMessagesButton = -2
   ChatIdentifier = -1,
   Unknown = 0,
   Message = 1,

src/status/libstatus/mailservers.nim

@@ -63,10 +63,13 @@ proc update*(peer: string) =
 proc delete*(peer: string) =
   discard callPrivateRPC("mailservers_deleteMailserver", %* [peer])
 
-proc requestMessages*(topics: seq[string], symKeyID: string, peer: string, numberOfMessages: int, fromTimestamp: int64 = 0) =
+proc requestMessages*(topics: seq[string], symKeyID: string, peer: string, numberOfMessages: int, fromTimestamp: int64 = 0, toTimestamp: int64 = 0, force: bool = false) =
-  var fromValue = (times.toUnix(times.getTime()) - 86400)
+  var toValue = times.toUnix(times.getTime())
+  var fromValue = toValue - 86400
   if fromTimestamp != 0:
     fromValue = fromTimestamp
+  if toTimestamp != 0:
+    toValue = toTimestamp
 
   echo callPrivateRPC("requestMessages".prefix, %* [
     {
@@ -76,7 +79,9 @@ proc requestMessages*(topics: seq[string], symKeyID: string, peer: string, numbe
         "timeout": 30,
         "limit": numberOfMessages,
         "cursor": nil,
-        "from": fromValue
+        "from": fromValue,
+        "to": toValue,
+        "force": force
     }
   ])
 

src/status/mailservers.nim

@@ -1,4 +1,4 @@
-import algorithm, json, random, math, os, tables, sets, chronicles, eventemitter, sequtils, locks
+import algorithm, json, random, math, os, tables, sets, chronicles, eventemitter, sequtils, locks, sugar
 import libstatus/core as status_core
 import libstatus/chat as status_chat
 import libstatus/mailservers as status_mailservers
@@ -128,10 +128,10 @@ proc peerSummaryChange*(self: MailserverModel, peers: seq[string]) =
     self.nodes[peer] = MailserverStatus.Connected
     self.events.emit("peerConnected", MailserverArg(peer: peer))
 
-proc requestMessages*(self: MailserverModel, topics: seq[string], fromValue: int64 = 0) =
+proc requestMessages*(self: MailserverModel, topics: seq[string], fromValue: int64 = 0, toValue: int64 = 0, force: bool = false) =
   debug "Requesting messages from", mailserver=self.selectedMailserver
   let generatedSymKey = status_chat.generateSymKeyFromPassword()
-  status_mailservers.requestMessages(topics, generatedSymKey, self.selectedMailserver, 1000, fromValue)
+  status_mailservers.requestMessages(topics, generatedSymKey, self.selectedMailserver, 1000, fromValue, toValue, force)
 
 proc getMailserverTopics*(self: MailserverModel): seq[MailserverTopic] =
   let response = status_mailservers.getMailserverTopics()
@@ -147,6 +147,10 @@ proc getMailserverTopics*(self: MailserverModel): seq[MailserverTopic] =
         lastRequest: topic["last-request"].getInt
       ))
 
+proc getMailserverTopicsByChatId*(self: MailserverModel, chatId: string): seq[MailServerTopic] =
+  result = self.getMailserverTopics()
+      .filter(topic => topic.chatIds.contains(chatId))
+
 proc addMailserverTopic*(self: MailserverModel, topic: MailserverTopic) =
   discard status_mailservers.addMailserverTopic(topic)
 

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

@@ -75,6 +75,8 @@ Item {
             switch(contentType) {
                 case Constants.chatIdentifier:
                     return channelIdentifierComponent
+                case Constants.fetchMoreMessagesButton:
+                    return fetchMoreMessagesButtonComponent
                 case Constants.systemMessagePrivateGroupType:
                     return privateGroupHeaderComponent
                 default:
@@ -83,6 +85,50 @@ Item {
         }
     }
 
+    Component {
+        id: fetchMoreMessagesButtonComponent
+        Item {
+            id: wrapper
+            height: wrapper.visible ? fetchMoreButton.height + fetchDate.height + 3 + Style.current.smallPadding*2 : 0
+            anchors.left: parent.left
+            anchors.right: parent.right
+            Separator {
+                id: sep1
+            }
+            StyledText {
+                id: fetchMoreButton
+                font.weight: Font.Medium
+                font.pixelSize: 15
+                color: Style.current.blue
+                text: qsTr("↓ Fetch more messages")
+                horizontalAlignment: Text.AlignHCenter
+                anchors.horizontalCenter: parent.horizontalCenter
+                anchors.top: sep1.bottom
+                anchors.topMargin: Style.current.smallPadding
+                MouseArea {
+                  cursorShape: Qt.PointingHandCursor
+                  anchors.fill: parent
+                  onClicked: {
+                    chatsModel.requestMoreMessages()
+                  }
+                }
+            }
+            StyledText {
+                id: fetchDate
+                anchors.top: fetchMoreButton.bottom
+                anchors.topMargin: 3
+                anchors.horizontalCenter: parent.horizontalCenter
+                horizontalAlignment: Text.AlignHCenter
+                color: Style.current.darkGrey
+                text: qsTr("before %1").arg(new Date(chatsModel.oldestMsgTimestamp*1000).toDateString())
+            }
+            Separator {
+                anchors.top: fetchDate.bottom
+                anchors.topMargin: Style.current.smallPadding
+            }
+        }
+    }
+
     Component {
         id: channelIdentifierComponent
         ChannelIdentifier {

ui/imports/Constants.qml

@@ -7,6 +7,7 @@ QtObject {
     readonly property int chatTypePublic: 2
     readonly property int chatTypePrivateGroupChat: 3
 
+    readonly property int fetchMoreMessagesButton: -2
     readonly property int chatIdentifier: -1
     readonly property int unknownContentType: 0
     readonly property int messageType: 1