Enable user mentions in Rich Text Editor

RiotSwiftUI/Modules/Room/Composer/Model/ComposerModels.swift

@@ -229,12 +229,14 @@ enum ComposerViewAction: Equatable {
     case contentDidChange(isEmpty: Bool)
     case linkTapped(linkAction: LinkAction)
     case storeSelection(selection: NSRange)
+    case suggestion(pattern: SuggestionPattern?)
 }
 
 enum ComposerViewModelResult: Equatable {
     case cancel
     case contentDidChange(isEmpty: Bool)
     case linkTapped(LinkAction: LinkAction)
+    case suggestion(pattern: SuggestionPattern?)
 }
 
 final class LinkActionWrapper: NSObject {
@@ -245,3 +247,12 @@ final class LinkActionWrapper: NSObject {
         super.init()
     }
 }
+
+final class SuggestionPatternWrapper: NSObject {
+    let suggestionPattern: SuggestionPattern?
+
+    init(_ suggestionPattern: SuggestionPattern?) {
+        self.suggestionPattern = suggestionPattern
+        super.init()
+    }
+}

RiotSwiftUI/Modules/Room/Composer/View/Composer.swift

@@ -248,6 +248,9 @@ struct Composer: View {
                 wysiwygViewModel.maximised = false
             }
         }
+        .onChange(of: wysiwygViewModel.suggestionPattern) { newValue in
+            sendMentionPattern(pattern: newValue)
+        }
     }
     
     private func storeCurrentSelection() {
@@ -258,6 +261,10 @@ struct Composer: View {
         let linkAction = wysiwygViewModel.getLinkAction()
         viewModel.send(viewAction: .linkTapped(linkAction: linkAction))
     }
+
+    private func sendMentionPattern(pattern: SuggestionPattern?) {
+        viewModel.send(viewAction: .suggestion(pattern: pattern))
+    }
 }
 
 private extension WysiwygComposerViewModel {

RiotSwiftUI/Modules/Room/Composer/ViewModel/ComposerViewModel.swift

@@ -90,6 +90,8 @@ final class ComposerViewModel: ComposerViewModelType, ComposerViewModelProtocol
             callback?(.linkTapped(LinkAction: linkAction))
         case let .storeSelection(selection):
             selectionToRestore = selection
+        case let .suggestion(pattern: pattern):
+            callback?(.suggestion(pattern: pattern))
         }
     }