Add Actions to Text Attachments

Author: thecoolwinter

Sources/CodeEditTextView/TextLayoutManager/TextAttachments/TextAttachment.swift

@@ -7,11 +7,29 @@
 
 import AppKit
 
+public enum TextAttachmentAction {
+    /// Perform no action.
+    case none
+    /// Replace the attachment range with the given string.
+    case replace(text: String)
+    /// Discard the attachment and perform no other action, this is the default action.
+    case discard
+}
+
 /// Represents an attachment type. Attachments take up some set width, and draw their contents in a receiver view.
 public protocol TextAttachment: AnyObject {
     var width: CGFloat { get }
     var isSelected: Bool { get set }
+
     func draw(in context: CGContext, rect: NSRect)
+
+    /// The action that should be performed when this attachment is invoked (double-click, enter pressed).
+    /// This method is optional, by default the attachment is discarded.
+    func attachmentAction() -> TextAttachmentAction
+}
+
+public extension TextAttachment {
+    func attachmentAction() -> TextAttachmentAction { .discard }
 }
 
 /// Type-erasing type for ``TextAttachment`` that also contains range information about the attachment.

Sources/CodeEditTextView/TextLayoutManager/TextAttachments/TextAttachmentManager.swift

@@ -102,7 +102,7 @@ public final class TextAttachmentManager {
     /// - Returns: An array of `AnyTextAttachment` instances whose ranges intersect `query`.
     public func getAttachmentsOverlapping(_ range: NSRange) -> [AnyTextAttachment] {
         // Find the first attachment whose end is beyond the start of the query.
-        guard let startIdx = firstIndex(where: { $0.range.upperBound >= range.location }) else {
+        guard let startIdx = orderedAttachments.firstIndex(where: { $0.range.upperBound >= range.location }) else {
             return []
         }
 

Sources/CodeEditTextView/TextLayoutManager/TextLayoutManager+Public.swift

@@ -339,4 +339,12 @@ extension TextLayoutManager {
             height: lineFragment.scaledHeight
         ).pixelAligned
     }
+
+    func contentRun(at offset: Int) -> LineFragment.FragmentContent? {
+        guard let textLine = textLineForOffset(offset),
+              let fragment = textLine.data.lineFragments.getLine(atOffset: offset - textLine.range.location) else {
+            return nil
+        }
+        return fragment.data.findContent(at: offset - textLine.range.location - fragment.range.location)?.content
+    }
 }

Sources/CodeEditTextView/TextSelectionManager/TextSelectionManager.swift

@@ -80,7 +80,6 @@ public class TextSelectionManager: NSObject {
         textSelections = [selection]
         updateSelectionViews()
         NotificationCenter.default.post(Notification(name: Self.selectionChangedNotification, object: self))
-        delegate?.setNeedsDisplay()
     }
 
     /// Set the selected ranges to new ranges. Overrides any existing selections.

Sources/CodeEditTextView/TextView/TextView+Mouse.swift

@@ -12,11 +12,17 @@ extension TextView {
         // Set cursor
         guard isSelectable,
               event.type == .leftMouseDown,
-              let offset = layoutManager.textOffsetAtPoint(self.convert(event.locationInWindow, from: nil)) else {
+              let offset = layoutManager.textOffsetAtPoint(self.convert(event.locationInWindow, from: nil)),
+              let content = layoutManager.contentRun(at: offset) else {
             super.mouseDown(with: event)
             return
         }
 
+        if case let .attachment(attachment) = content.data, event.clickCount < 3 {
+            handleAttachmentClick(event: event, offset: offset, attachment: attachment)
+            return
+        }
+
         switch event.clickCount {
         case 1:
             handleSingleClick(event: event, offset: offset)
@@ -76,6 +82,26 @@ extension TextView {
         selectLine(nil)
     }
 
+    fileprivate func handleAttachmentClick(event: NSEvent, offset: Int, attachment: AnyTextAttachment) {
+        switch event.clickCount {
+        case 1:
+            selectionManager.setSelectedRange(attachment.range)
+        case 2:
+            let action = attachment.attachment.attachmentAction()
+            switch action {
+            case .none:
+                return
+            case .discard:
+                layoutManager.attachments.remove(atOffset: offset)
+                selectionManager.setSelectedRange(NSRange(location: attachment.range.location, length: 0))
+            case let .replace(text):
+                replaceCharacters(in: attachment.range, with: text)
+            }
+        default:
+            break
+        }
+    }
+
     override public func mouseUp(with event: NSEvent) {
         mouseDragAnchor = nil
         disableMouseAutoscrollTimer()