ios: members connected aggregated item (#2900)

* ios: members connected aggregated item

* wrapping hstack wip

* Revert "wrapping hstack wip"

This reverts commit 75af7473fc.

* redesign

* fix scroll

* revert

* comment

* remove padding

* brackets

* texts, icon

* optimize - collect only member names

* refactor

* check different index

* refactor 2

---------

Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>

apps/ios/Shared/Model/ChatModel.swift

@@ -484,13 +484,21 @@ final class ChatModel: ObservableObject {
     }
 
     func getPrevChatItem(_ ci: ChatItem) -> ChatItem? {
-        if let i = getChatItemIndex(ci), i < reversedChatItems.count - 1  {
+        if let i = getChatItemIndex(ci), i + 1 < reversedChatItems.count  {
             return reversedChatItems[i + 1]
         } else {
             return nil
         }
     }
 
+    func getNextChatItem(_ ci: ChatItem) -> ChatItem? {
+        if let i = getChatItemIndex(ci), i > 0  {
+            return reversedChatItems[i - 1]
+        } else {
+            return nil
+        }
+    }
+    
     func popChat(_ id: String) {
         if let i = getChatIndex(id) {
             popChat_(i)

apps/ios/Shared/Views/Chat/ChatItem/CIEventView.swift

@@ -10,20 +10,11 @@ import SwiftUI
 import SimpleXChat
 
 struct CIEventView: View {
-    var chatItem: ChatItem
+    var eventText: Text
 
     var body: some View {
         HStack(alignment: .bottom, spacing: 0) {
-            if let member = chatItem.memberDisplayName {
-                Text(member)
-                    .font(.caption)
-                    .foregroundColor(.secondary)
-                    .fontWeight(.light)
-                + Text(" ")
-                + chatEventText(chatItem)
-            } else {
-                chatEventText(chatItem)
-            }
+            eventText
         }
         .padding(.leading, 6)
         .padding(.bottom, 6)
@@ -31,20 +22,8 @@ struct CIEventView: View {
     }
 }
 
-func chatEventText(_ ci: ChatItem) -> Text {
-    Text(ci.content.text)
-        .font(.caption)
-        .foregroundColor(.secondary)
-        .fontWeight(.light)
-    + Text(" ")
-    + ci.timestampText
-        .font(.caption)
-        .foregroundColor(Color.secondary)
-        .fontWeight(.light)
-}
-
 struct CIEventView_Previews: PreviewProvider {
     static var previews: some View {
-        CIEventView(chatItem: ChatItem.getGroupEventSample())
+        CIEventView(eventText: Text("event happened"))
     }
 }

apps/ios/Shared/Views/Chat/ChatItemView.swift

@@ -58,6 +58,7 @@ struct ChatItemView: View {
 }
 
 struct ChatItemContentView<Content: View>: View {
+    @EnvironmentObject var chatModel: ChatModel
     var chatInfo: ChatInfo
     var chatItem: ChatItem
     var showMember: Bool
@@ -75,6 +76,7 @@ struct ChatItemContentView<Content: View>: View {
         case let .rcvDecryptionError(msgDecryptError, msgCount): CIRcvDecryptionError(msgDecryptError: msgDecryptError, msgCount: msgCount, chatItem: chatItem, showMember: showMember)
         case let .rcvGroupInvitation(groupInvitation, memberRole): groupInvitationItemView(groupInvitation, memberRole)
         case let .sndGroupInvitation(groupInvitation, memberRole): groupInvitationItemView(groupInvitation, memberRole)
+        case .rcvGroupEvent(.memberConnected): CIEventView(eventText: membersConnectedItemText())
         case .rcvGroupEvent: eventItemView()
         case .sndGroupEvent: eventItemView()
         case .rcvConnEvent: eventItemView()
@@ -108,12 +110,84 @@ struct ChatItemContentView<Content: View>: View {
     }
 
     private func eventItemView() -> some View {
-        CIEventView(chatItem: chatItem)
+        return CIEventView(eventText: eventItemViewText())
+    }
+
+    private func eventItemViewText() -> Text {
+        if let member = chatItem.memberDisplayName {
+            return Text(member)
+                    .font(.caption)
+                    .foregroundColor(.secondary)
+                    .fontWeight(.light)
+                + Text(" ")
+                + chatEventText(chatItem)
+        } else {
+            return chatEventText(chatItem)
+        }
     }
 
     private func chatFeatureView(_ feature: Feature, _ iconColor: Color) -> some View {
         CIChatFeatureView(chatItem: chatItem, feature: feature, iconColor: iconColor)
     }
+
+    private func membersConnectedItemText() -> Text {
+        if case let .groupRcv(member) = chatItem.chatDir,
+           let prevItem = chatModel.getPrevChatItem(chatItem),
+           let prevMember = prevItem.memberConnected,
+           let membersConnectedText = membersConnectedText(connectedMemberNames(member, prevMember, prevItem)) {
+            return chatEventText(membersConnectedText, chatItem.timestampText)
+        } else {
+            return eventItemViewText()
+        }
+
+        func connectedMemberNames(_ member: GroupMember, _ prevMember: GroupMember, _ prevItem: ChatItem) -> [String] {
+            [member.chatViewName, prevMember.chatViewName] + collectPrevConnectedMemberNames(prevItem)
+        }
+    }
+
+    private func collectPrevConnectedMemberNames(_ ci: ChatItem) -> [String] {
+        guard let prevItem = chatModel.getPrevChatItem(ci),
+              let memberConnected = prevItem.memberConnected else {
+            return []
+        }
+        let prevMemberNames = collectPrevConnectedMemberNames(prevItem)
+        return [memberConnected.chatViewName] + prevMemberNames
+    }
+
+    private func membersConnectedText(_ memberNames: [String]) -> String? {
+        if memberNames.count > 3 {
+            return String.localizedStringWithFormat(
+                NSLocalizedString("%@ and %d other members connected", comment: "<member_names> and <n >= 2> other members connected (plural)"),
+                Array(memberNames.prefix(2)).joined(separator: ", "),
+                memberNames.count - 2
+            )
+        } else if memberNames.count >= 2,
+                  let lastMemberName = memberNames.last {
+            return String.localizedStringWithFormat(
+                NSLocalizedString("%@ and %@ connected", comment: "<member_name(s)> and <member_name> connected (plural)"),
+                memberNames.dropLast().joined(separator: ", "),
+                lastMemberName
+            )
+        } else {
+            return nil
+        }
+    }
+}
+
+func chatEventText(_ eventText: String, _ ts: Text) -> Text {
+    Text(eventText)
+        .font(.caption)
+        .foregroundColor(.secondary)
+        .fontWeight(.light)
+    + Text(" ")
+    + ts
+        .font(.caption)
+        .foregroundColor(Color.secondary)
+        .fontWeight(.light)
+}
+
+func chatEventText(_ ci: ChatItem) -> Text {
+    chatEventText(ci.content.text, ci.timestampText)
 }
 
 struct ChatItemView_Previews: PreviewProvider {

apps/ios/Shared/Views/Chat/ChatView.swift

@@ -261,7 +261,7 @@ struct ChatView: View {
         return GeometryReader { g in
             ScrollViewReader { proxy in
                 ScrollView {
-                    LazyVStack(spacing: 5)  {
+                    LazyVStack(spacing: 0)  {
                         ForEach(chatModel.reversedChatItems, id: \.viewId) { ci in
                             let voiceNoFrame = voiceWithoutFrame(ci)
                             let maxWidth = cInfo.chatType == .group
@@ -430,6 +430,11 @@ struct ChatView: View {
     @ViewBuilder private func chatItemView(_ ci: ChatItem, _ maxWidth: CGFloat) -> some View {
         if case let .groupRcv(member) = ci.chatDir,
            case let .group(groupInfo) = chat.chatInfo {
+            let nextItem = chatModel.getNextChatItem(ci)
+            if ci.memberConnected != nil && nextItem?.memberConnected != nil {
+                // memberConnected events are aggregated at the last chat item in a row of such events, see ChatItemView
+                ZStack {} // scroll doesn't work if it's EmptyView()
+            } else {
                 let prevItem = chatModel.getPrevChatItem(ci)
                 HStack(alignment: .top, spacing: 0) {
                     let showMember = prevItem == nil || showMemberImage(member, prevItem)
@@ -459,6 +464,8 @@ struct ChatView: View {
                 }
                 .padding(.trailing)
                 .padding(.leading, 12)
+                .padding(.bottom, 5)
+            }
         } else {
             ChatItemWithMenu(
                 ci: ci,
@@ -470,6 +477,7 @@ struct ChatView: View {
                 showDeleteMessage: $showDeleteMessage
             )
             .padding(.horizontal)
+            .padding(.bottom, 5)
             .environmentObject(chat)
         }
     }

apps/ios/SimpleXChat/ChatTypes.swift

@@ -2021,6 +2021,17 @@ public struct ChatItem: Identifiable, Decodable {
         }
     }
 
+    public var memberConnected: GroupMember? {
+        switch chatDir {
+        case .groupRcv(let groupMember):
+            switch content {
+            case .rcvGroupEvent(rcvGroupEvent: .memberConnected): return groupMember
+            default: return nil
+            }
+        default: return nil
+        }
+    }
+
     private var showNtfDir: Bool {
         return !chatDir.sent
     }