Accept current autocorrection/suggestion before sending a message (#3219)

* Fixes #3216 - Accept current autocorrection/suggestion before sending a message.

* Switch from a temporary textField to `inputDelegate` selection changes

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/ComposerToolbarModels.swift

@@ -133,6 +133,8 @@ struct ComposerToolbarViewStateBindings {
     var composerExpanded = false
     var formatItems: [FormatItem] = .init()
     var alertInfo: AlertInfo<UUID>?
+    
+    var presendCallback: (() -> Void)?
 }
 
 /// An item in the toolbar

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/View/ComposerToolbar.swift

@@ -137,7 +137,7 @@ struct ComposerToolbar: View {
     
     private var sendButton: some View {
         Button {
-            context.send(viewAction: .sendMessage)
+            sendMessage()
         } label: {
             CompoundIcon(context.viewState.composerMode.isEdit ? \.check : \.sendSolid)
                 .scaledPadding(6, relativeTo: .title)
@@ -156,12 +156,13 @@ struct ComposerToolbar: View {
     
     private var messageComposer: some View {
         MessageComposer(plainComposerText: $context.plainComposerText,
+                        presendCallback: $context.presendCallback,
                         composerView: composerView,
                         mode: context.viewState.composerMode,
                         composerFormattingEnabled: context.composerFormattingEnabled,
                         showResizeGrabber: context.composerFormattingEnabled,
                         isExpanded: $context.composerExpanded) {
-            context.send(viewAction: .sendMessage)
+            sendMessage()
         } editAction: {
             context.send(viewAction: .editLastMessage)
         } pasteAction: { provider in
@@ -205,6 +206,17 @@ struct ComposerToolbar: View {
         }
     }
     
+    private func sendMessage() {
+        // Allow the inner TextField do apply any final processing before
+        // sending e.g. accepting current autocorrection.
+        // Fixes https://github.com/element-hq/element-x-ios/issues/3216
+        context.presendCallback?()
+
+        DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+            context.send(viewAction: .sendMessage)
+        }
+    }
+    
     private var placeholder: String {
         switch context.viewState.composerMode {
         case .reply(_, _, let isThread):

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/View/MessageComposer.swift

@@ -23,6 +23,7 @@ typealias PasteHandler = (NSItemProvider) -> Void
 
 struct MessageComposer: View {
     @Binding var plainComposerText: NSAttributedString
+    @Binding var presendCallback: (() -> Void)?
     let composerView: WysiwygComposerView
     let mode: ComposerMode
     let composerFormattingEnabled: Bool
@@ -86,6 +87,7 @@ struct MessageComposer: View {
             } else {
                 MessageComposerTextField(placeholder: L10n.richTextEditorComposerPlaceholder,
                                          text: $plainComposerText,
+                                         presendCallback: $presendCallback,
                                          maxHeight: 300,
                                          keyHandler: { handleKeyPress($0) },
                                          pasteHandler: pasteAction)
@@ -253,6 +255,7 @@ struct MessageComposer_Previews: PreviewProvider, TestablePreview {
                                                pasteHandler: nil)
         
         return MessageComposer(plainComposerText: .constant(content),
+                               presendCallback: .constant(nil),
                                composerView: composerView,
                                mode: mode,
                                composerFormattingEnabled: false,

ElementX/Sources/Screens/RoomScreen/ComposerToolbar/View/MessageComposerTextField.swift

@@ -18,6 +18,7 @@ import SwiftUI
 struct MessageComposerTextField: View {
     let placeholder: String
     @Binding var text: NSAttributedString
+    @Binding var presendCallback: (() -> Void)?
 
     let maxHeight: CGFloat
     let keyHandler: GenericKeyHandler
@@ -25,6 +26,7 @@ struct MessageComposerTextField: View {
 
     var body: some View {
         UITextViewWrapper(text: $text,
+                          presendCallback: $presendCallback,
                           maxHeight: maxHeight,
                           keyHandler: keyHandler,
                           pasteHandler: pasteHandler)
@@ -58,6 +60,7 @@ private struct UITextViewWrapper: UIViewRepresentable {
     @Environment(\.timelineContext) private var timelineContext
 
     @Binding var text: NSAttributedString
+    @Binding var presendCallback: (() -> Void)?
 
     let maxHeight: CGFloat
 
@@ -68,8 +71,8 @@ private struct UITextViewWrapper: UIViewRepresentable {
 
     func makeUIView(context: UIViewRepresentableContext<UITextViewWrapper>) -> UITextView {
         // Need to use TextKit 1 for mentions
-        let textView = ElementTextView(usingTextLayoutManager: false)
-        textView.timelineContext = timelineContext
+        let textView = ElementTextView(timelineContext: timelineContext,
+                                       presendCallback: $presendCallback)
         
         textView.delegate = context.coordinator
         textView.elementDelegate = context.coordinator
@@ -182,12 +185,29 @@ private protocol ElementTextViewDelegate: AnyObject {
 }
 
 private class ElementTextView: UITextView, PillAttachmentViewProviderDelegate {
-    var timelineContext: TimelineViewModel.Context?
+    private(set) var timelineContext: TimelineViewModel.Context?
+    private var presendCallback: Binding<(() -> Void)?>
+    private var pillViews = NSHashTable<UIView>.weakObjects()
     
     weak var elementDelegate: ElementTextViewDelegate?
     
-    private var pillViews = NSHashTable<UIView>.weakObjects()
-
+    init(timelineContext: TimelineViewModel.Context?,
+         presendCallback: Binding<(() -> Void)?>) {
+        self.timelineContext = timelineContext
+        self.presendCallback = presendCallback
+        
+        super.init(frame: .zero, textContainer: nil)
+        
+        presendCallback.wrappedValue = { [weak self] in
+            self?.acceptCurrentSuggestion()
+        }
+    }
+    
+    @available(*, unavailable)
+    required init?(coder: NSCoder) {
+        fatalError()
+    }
+    
     override var keyCommands: [UIKeyCommand]? {
         [UIKeyCommand(input: "\r", modifierFlags: .shift, action: #selector(shiftEnterKeyPressed)),
          UIKeyCommand(input: "\r", modifierFlags: [], action: #selector(enterKeyPressed))]
@@ -270,6 +290,17 @@ private class ElementTextView: UITextView, PillAttachmentViewProviderDelegate {
         }
         pillViews.removeAllObjects()
     }
+    
+    // MARK: - Private
+    
+    private func acceptCurrentSuggestion() {
+        guard isFirstResponder else {
+            return
+        }
+        
+        inputDelegate?.selectionWillChange(self)
+        inputDelegate?.selectionDidChange(self)
+    }
 }
 
 struct MessageComposerTextField_Previews: PreviewProvider, TestablePreview {
@@ -292,6 +323,7 @@ struct MessageComposerTextField_Previews: PreviewProvider, TestablePreview {
         var body: some View {
             MessageComposerTextField(placeholder: "Placeholder",
                                      text: $text,
+                                     presendCallback: .constant(nil),
                                      maxHeight: 300,
                                      keyHandler: { _ in },
                                      pasteHandler: { _ in })