[iOS] Handle paste and key commands

platforms/ios/example/Wysiwyg.xcodeproj/project.pbxproj

@@ -147,9 +147,9 @@
 				A6472CAA2886CF830021A0E8 /* WysiwygApp.swift */,
 				A6472CAE2886CF840021A0E8 /* Assets.xcassets */,
 				A6F3FC0228D4659E00C170E8 /* Extensions */,
+				A6E13E4629A7AB3600A85A55 /* Mocks */,
 				A6F4D0CD29AE0BE100087A3E /* Pills */,
 				A6472CB02886CF840021A0E8 /* Preview Content */,
-				A6E13E4629A7AB3600A85A55 /* Mocks */,
 				A6C2157A28C0F63400C8E727 /* Views */,
 			);
 			path = Wysiwyg;

platforms/ios/example/Wysiwyg/Views/Composer.swift

@@ -21,6 +21,9 @@ import WysiwygComposer
 /// that grows to a max height.
 struct Composer: View {
     @ObservedObject var viewModel: WysiwygComposerViewModel
+    let itemProviderHelper: WysiwygItemProviderHelper?
+    let keyCommandHandler: KeyCommandHandler?
+    let pasteHandler: PasteHandler?
     let minTextViewHeight: CGFloat = 20
     let borderHeight: CGFloat = 40
     @State var focused = false
@@ -34,7 +37,10 @@ struct Composer: View {
             HStack {
                 WysiwygComposerView(
                     focused: $focused,
-                    viewModel: viewModel
+                    viewModel: viewModel,
+                    itemProviderHelper: itemProviderHelper,
+                    keyCommandHandler: keyCommandHandler,
+                    pasteHandler: pasteHandler
                 )
                 .tintColor(.green)
                 .placeholder("Placeholder", color: .gray)
@@ -75,6 +81,9 @@ struct Composer: View {
 struct Composer_Previews: PreviewProvider {
     static let viewModel = WysiwygComposerViewModel()
     static var previews: some View {
-        Composer(viewModel: viewModel)
+        Composer(viewModel: viewModel,
+                 itemProviderHelper: nil,
+                 keyCommandHandler: nil,
+                 pasteHandler: nil)
     }
 }

platforms/ios/example/Wysiwyg/Views/ContentView.swift

@@ -34,7 +34,19 @@ struct ContentView: View {
     var body: some View {
         Spacer()
             .frame(width: nil, height: 50, alignment: .center)
-        Composer(viewModel: viewModel)
+        Composer(viewModel: viewModel,
+                 itemProviderHelper: nil,
+                 keyCommandHandler: { keyCommand in
+                     switch keyCommand {
+                     case .enter:
+                         sentMessage = viewModel.content
+                         viewModel.clearContent()
+                         return true
+                     case .shiftEnter:
+                         return false
+                     }
+                 },
+                 pasteHandler: { _ in })
         Button("Force crash") {
             viewModel.setHtmlContent("<//strong>")
         }

platforms/ios/lib/WysiwygComposer/Sources/WysiwygComposer/Components/WysiwygComposerView/WysiwygComposerView.swift

@@ -17,11 +17,34 @@
 import OSLog
 import SwiftUI
 
+/// A protocol to implement in order to inform the composer if a specific item
+/// can be pasted into the application.
+public protocol WysiwygItemProviderHelper {
+    /// Determine if the item attached to given item provider can be pasted into the application.
+    ///
+    /// - Parameter itemProvider: The item provider.
+    /// - Returns: True if it can be pasted, false otherwise.
+    func isPasteSupported(for itemProvider: NSItemProvider) -> Bool
+}
+
+/// Handler for key commands.
+public typealias KeyCommandHandler = (WysiwygKeyCommand) -> Bool
+/// Handler for paste events.
+public typealias PasteHandler = (NSItemProvider) -> Void
+
 /// Provides a SwiftUI displayable view for the composer UITextView component.
 public struct WysiwygComposerView: UIViewRepresentable {
     // MARK: - Public
 
+    /// Binding var handling whether the composer is currently focused or not.
     @Binding public var focused: Bool
+    /// A helper to determine if an item can be pasted into the hosting application.
+    /// If omitted, most non-text paste events will be ignored.
+    let itemProviderHelper: WysiwygItemProviderHelper?
+    /// A handler for key commands. If omitted, default behaviour will be applied. See `WysiwygKeyCommand.swift`.
+    let keyCommandHandler: KeyCommandHandler?
+    /// A handler for paste events. If omitted, the composer will try to paste content as raw text.
+    let pasteHandler: PasteHandler?
 
     // MARK: - Private
 
@@ -33,8 +56,14 @@ public struct WysiwygComposerView: UIViewRepresentable {
     // MARK: - Public
 
     public init(focused: Binding<Bool>,
-                viewModel: WysiwygComposerViewModelProtocol) {
+                viewModel: WysiwygComposerViewModelProtocol,
+                itemProviderHelper: WysiwygItemProviderHelper?,
+                keyCommandHandler: KeyCommandHandler?,
+                pasteHandler: PasteHandler?) {
         _focused = focused
+        self.itemProviderHelper = itemProviderHelper
+        self.keyCommandHandler = keyCommandHandler
+        self.pasteHandler = pasteHandler
         self.viewModel = viewModel
     }
 
@@ -54,6 +83,7 @@ public struct WysiwygComposerView: UIViewRepresentable {
         textView.backgroundColor = .clear
         textView.tintColor = UIColor(tintColor)
         textView.clipsToBounds = false
+        textView.wysiwygDelegate = context.coordinator
         textView.placeholderFont = UIFont.preferredFont(forTextStyle: .body)
         textView.placeholderColor = UIColor(placeholderColor)
         textView.placeholder = placeholder
@@ -74,23 +104,44 @@ public struct WysiwygComposerView: UIViewRepresentable {
     }
 
     public func makeCoordinator() -> Coordinator {
-        Coordinator($focused, viewModel.replaceText, viewModel.select, viewModel.didUpdateText)
+        Coordinator($focused,
+                    viewModel.replaceText,
+                    viewModel.select,
+                    viewModel.didUpdateText,
+                    viewModel.enter,
+                    itemProviderHelper: itemProviderHelper,
+                    keyCommandHandler: keyCommandHandler,
+                    pasteHandler: pasteHandler)
     }
 
     /// Coordinates UIKit communication.
-    public class Coordinator: NSObject, UITextViewDelegate, NSTextStorageDelegate {
+    public class Coordinator: NSObject, UITextViewDelegate, NSTextStorageDelegate, WysiwygTextViewDelegate {
         var focused: Binding<Bool>
         var replaceText: (NSRange, String) -> Bool
         var select: (NSRange) -> Void
         var didUpdateText: () -> Void
+        var enter: () -> Void
+
+        private let itemProviderHelper: WysiwygItemProviderHelper?
+        private let keyCommandHandler: KeyCommandHandler?
+        private let pasteHandler: PasteHandler?
+
         init(_ focused: Binding<Bool>,
              _ replaceText: @escaping (NSRange, String) -> Bool,
              _ select: @escaping (NSRange) -> Void,
-             _ didUpdateText: @escaping () -> Void) {
+             _ didUpdateText: @escaping () -> Void,
+             _ enter: @escaping () -> Void,
+             itemProviderHelper: WysiwygItemProviderHelper?,
+             keyCommandHandler: KeyCommandHandler?,
+             pasteHandler: PasteHandler?) {
             self.focused = focused
             self.replaceText = replaceText
             self.select = select
             self.didUpdateText = didUpdateText
+            self.enter = enter
+            self.itemProviderHelper = itemProviderHelper
+            self.keyCommandHandler = keyCommandHandler
+            self.pasteHandler = pasteHandler
         }
 
         public func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
@@ -137,6 +188,37 @@ public struct WysiwygComposerView: UIViewRepresentable {
             textView.selectedRange = characterRange
             return false
         }
+
+        func isPasteSupported(for itemProvider: NSItemProvider) -> Bool {
+            guard let itemProviderHelper else {
+                return false
+            }
+
+            return itemProviderHelper.isPasteSupported(for: itemProvider)
+        }
+
+        func textViewDidReceiveKeyCommand(_ textView: UITextView, keyCommand: WysiwygKeyCommand) {
+            if !handleKeyCommand(keyCommand) {
+                processDefault(for: keyCommand)
+            }
+        }
+
+        func textView(_ textView: UITextView, didReceivePasteWith provider: NSItemProvider) {
+            pasteHandler?(provider)
+        }
+
+        private func handleKeyCommand(_ keyCommand: WysiwygKeyCommand) -> Bool {
+            guard let keyCommandHandler else { return false }
+
+            return keyCommandHandler(keyCommand)
+        }
+
+        private func processDefault(for keyCommand: WysiwygKeyCommand) {
+            switch keyCommand {
+            case .enter, .shiftEnter:
+                enter()
+            }
+        }
     }
 }
 

platforms/ios/lib/WysiwygComposer/Sources/WysiwygComposer/Components/WysiwygComposerView/WysiwygComposerViewModel.swift

@@ -301,16 +301,7 @@ public extension WysiwygComposerViewModel {
             update = model.backspace()
             shouldAcceptChange = false
         } else if replacementText.count == 1, replacementText[String.Index(utf16Offset: 0, in: replacementText)].isNewline {
-            update = model.enter()
-            // Pending formats need to be reapplied to the
-            // NSAttributedString upon next character input if we
-            // are in a structure that might add non-formatted
-            // representation chars to it (e.g. NBSP/ZWSP, list prefixes)
-            if !model
-                .reversedActions
-                .isDisjoint(with: [.codeBlock, .quote, .orderedList, .unorderedList]) {
-                hasPendingFormats = true
-            }
+            update = createEnterUpdate()
             shouldAcceptChange = false
         } else {
             update = model.replaceText(newText: replacementText)
@@ -386,6 +377,10 @@ public extension WysiwygComposerViewModel {
     func getLinkAction() -> LinkAction {
         model.getLinkAction()
     }
+
+    func enter() {
+        applyUpdate(createEnterUpdate(), skipTextViewUpdate: false)
+    }
 }
 
 // MARK: - Private
@@ -585,6 +580,20 @@ private extension WysiwygComposerViewModel {
 
         return markdownContent
     }
+
+    func createEnterUpdate() -> ComposerUpdate {
+        let update = model.enter()
+        // Pending formats need to be reapplied to the
+        // NSAttributedString upon next character input if we
+        // are in a structure that might add non-formatted
+        // representation chars to it (e.g. NBSP/ZWSP, list prefixes)
+        if !model
+            .reversedActions
+            .isDisjoint(with: [.codeBlock, .quote, .orderedList, .unorderedList]) {
+            hasPendingFormats = true
+        }
+        return update
+    }
 }
 
 // MARK: - ComposerModelWrapperDelegate

platforms/ios/lib/WysiwygComposer/Sources/WysiwygComposer/Components/WysiwygComposerView/WysiwygComposerViewModelProtocol.swift

@@ -38,4 +38,7 @@ public protocol WysiwygComposerViewModelProtocol: AnyObject {
 
     /// Notify that the text view content has changed.
     func didUpdateText()
+
+    /// Apply an enter/return key event.
+    func enter()
 }

platforms/ios/lib/WysiwygComposer/Sources/WysiwygComposer/Components/WysiwygComposerView/WysiwygTextView.swift

@@ -16,7 +16,34 @@
 
 import UIKit
 
+/// An internal delegate for the `WysiwygTextView`, used to bring paste and key commands events
+/// to SwiftUI through the `WysiwygComposerView` coordinator class.
+protocol WysiwygTextViewDelegate: AnyObject {
+    /// Asks the delegate if the item attached to given item provider can be pasted into the application.
+    ///
+    /// - Parameter itemProvider: The item provider.
+    /// - Returns: True if it can be pasted, false otherwise.
+    func isPasteSupported(for itemProvider: NSItemProvider) -> Bool
+
+    /// Notify the delegate that a key command has been received by the text view.
+    ///
+    /// - Parameters:
+    ///   - textView: Composer text view.
+    ///   - keyCommand: Key command received.
+    func textViewDidReceiveKeyCommand(_ textView: UITextView, keyCommand: WysiwygKeyCommand)
+
+    /// Notify the delegate that a paste event has beeb received by the text view.
+    ///
+    /// - Parameters:
+    ///   - textView: Composer text view.
+    ///   - provider: Item provider for the paste event.
+    func textView(_ textView: UITextView, didReceivePasteWith provider: NSItemProvider)
+}
+
 public class WysiwygTextView: UITextView {
+    /// Internal delegate for the text view.
+    weak var wysiwygDelegate: WysiwygTextViewDelegate?
+
     var shouldShowPlaceholder = true {
         didSet {
             setNeedsDisplay()
@@ -127,6 +154,49 @@ public class WysiwygTextView: UITextView {
                       width: rect.width,
                       height: glyphRect.height + 2 * Constants.caretVerticalOffset)
     }
+
+    // Enter Key commands support
+
+    override public var keyCommands: [UIKeyCommand]? {
+        WysiwygKeyCommand.allCases.map { UIKeyCommand(input: $0.input,
+                                                      modifierFlags: $0.modifierFlags,
+                                                      action: #selector(keyCommandAction)) }
+    }
+
+    @objc func keyCommandAction(sender: UIKeyCommand) {
+        guard let command = WysiwygKeyCommand.from(sender) else { return }
+
+        wysiwygDelegate?.textViewDidReceiveKeyCommand(self, keyCommand: command)
+    }
+
+    // Paste support
+
+    override public func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
+        guard !super.canPerformAction(action, withSender: sender) else {
+            return true
+        }
+
+        guard action == #selector(paste(_:)),
+              let itemProvider = UIPasteboard.general.itemProviders.first,
+              let wysiwygDelegate else {
+            return false
+        }
+
+        return wysiwygDelegate.isPasteSupported(for: itemProvider)
+    }
+
+    override public func paste(_ sender: Any?) {
+        guard let provider = UIPasteboard.general.itemProviders.first,
+              let wysiwygDelegate,
+              wysiwygDelegate.isPasteSupported(for: provider) else {
+            // If the item is not supported by the hosting application
+            // just try pasting its contents into the textfield
+            super.paste(sender)
+            return
+        }
+
+        wysiwygDelegate.textView(self, didReceivePasteWith: provider)
+    }
 }
 
 private extension WysiwygTextView {