Limit conversations a message can be forwarded to (#5793)

* Limit conversations a message can be forwarded to

* Review fixups

* fix: remove the unused constant argument

---------

Co-authored-by: Mauro Romito <mauro.romito@element.io>

ElementX/Sources/Screens/MessageForwardingScreen/MessageForwardingScreenModels.swift

@@ -16,8 +16,13 @@ enum MessageForwardingScreenViewModelAction {
 
 struct MessageForwardingScreenViewState: BindableState {
     var rooms: [MessageForwardingRoom] = []
-    var selectedRoomIDs = [String]()
+    var selectedRoomIDs: Set<String> = []
+    let maxRoomSelectionCount = 10
     var bindings = MessageForwardingScreenViewStateBindings()
+    
+    var isAtRoomSelectionLimit: Bool {
+        selectedRoomIDs.count >= maxRoomSelectionCount
+    }
 }
 
 struct MessageForwardingScreenViewStateBindings {

ElementX/Sources/Screens/MessageForwardingScreen/MessageForwardingScreenViewModel.swift

@@ -63,10 +63,10 @@ class MessageForwardingScreenViewModel: MessageForwardingScreenViewModelType, Me
         case .send:
             Task { await forward() }
         case .selectRoom(let roomID):
-            if let index = state.selectedRoomIDs.firstIndex(of: roomID) {
-                state.selectedRoomIDs.remove(at: index)
+            if state.selectedRoomIDs.contains(roomID) == false, state.selectedRoomIDs.count < state.maxRoomSelectionCount {
+                state.selectedRoomIDs.insert(roomID)
             } else {
-                state.selectedRoomIDs.append(roomID)
+                state.selectedRoomIDs.remove(roomID)
             }
         case .reachedTop:
             updateVisibleRange(edge: .top)

ElementX/Sources/Screens/MessageForwardingScreen/View/MessageForwardingScreen.swift

@@ -19,6 +19,7 @@ struct MessageForwardingScreen: View {
                 ForEach(context.viewState.rooms) { room in
                     MessageForwardingListRow(room: room,
                                              isSelected: context.viewState.selectedRoomIDs.contains(room.id),
+                                             isDisabled: context.viewState.isAtRoomSelectionLimit && !context.viewState.selectedRoomIDs.contains(room.id),
                                              context: context)
                 }
                 // Replace these with ScrollView's `scrollPosition` when dropping iOS 16.
@@ -68,6 +69,7 @@ private struct MessageForwardingListRow: View {
     
     let room: MessageForwardingRoom
     let isSelected: Bool
+    let isDisabled: Bool
     let context: MessageForwardingScreenViewModel.Context
     
     var body: some View {
@@ -77,6 +79,7 @@ private struct MessageForwardingListRow: View {
                 kind: .selection(isSelected: isSelected) {
                     context.send(viewAction: .selectRoom(roomID: room.id))
                 })
+                .disabled(isDisabled)
     }
     
     @ViewBuilder