add macOS BookTextView: NSViewRepresentable with NSAttributedString, highlight, click-to-seek, scroll-to-offset

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Vorleser-macOS/BookTextView.swift

@@ -0,0 +1,75 @@
+import SwiftUI
+import AppKit
+import VorleserKit
+
+struct BookTextView: NSViewRepresentable {
+	let attributedText: NSAttributedString
+	let highlightRange: Range<Int>?
+	let onClickCharacter: (CharacterOffset) -> Void
+	var scrollToOffset: CharacterOffset?
+
+	func makeNSView(context: Context) -> NSScrollView {
+		let scrollView = NSTextView.scrollableTextView()
+		let textView = scrollView.documentView as! NSTextView
+		textView.isEditable = false
+		textView.isSelectable = false
+		textView.textContainerInset = NSSize(width: 16, height: 16)
+
+		let click = NSClickGestureRecognizer(target: context.coordinator, action: #selector(Coordinator.handleClick(_:)))
+		textView.addGestureRecognizer(click)
+		context.coordinator.textView = textView
+
+		return scrollView
+	}
+
+	func updateNSView(_ scrollView: NSScrollView, context: Context) {
+		guard let textView = scrollView.documentView as? NSTextView else { return }
+
+		let highlighted = NSMutableAttributedString(attributedString: attributedText)
+
+		if let range = highlightRange,
+		   range.lowerBound >= 0,
+		   range.upperBound <= attributedText.length {
+			let nsRange = NSRange(location: range.lowerBound, length: range.upperBound - range.lowerBound)
+			highlighted.addAttribute(.backgroundColor, value: NSColor.systemYellow.withAlphaComponent(0.3), range: nsRange)
+		}
+
+		textView.textStorage?.setAttributedString(highlighted)
+
+		if let range = highlightRange,
+		   range.lowerBound >= 0,
+		   range.upperBound <= attributedText.length {
+			let nsRange = NSRange(location: range.lowerBound, length: range.upperBound - range.lowerBound)
+			textView.scrollRangeToVisible(nsRange)
+		}
+
+		if let offset = scrollToOffset,
+		   offset >= 0,
+		   offset < attributedText.length {
+			let nsRange = NSRange(location: offset, length: 1)
+			textView.scrollRangeToVisible(nsRange)
+		}
+	}
+
+	func makeCoordinator() -> Coordinator {
+		Coordinator(onClickCharacter: onClickCharacter)
+	}
+
+	class Coordinator: NSObject {
+		weak var textView: NSTextView?
+		let onClickCharacter: (CharacterOffset) -> Void
+
+		init(onClickCharacter: @escaping (CharacterOffset) -> Void) {
+			self.onClickCharacter = onClickCharacter
+		}
+
+		@objc func handleClick(_ gesture: NSClickGestureRecognizer) {
+			guard let textView else { return }
+			let point = gesture.location(in: textView)
+			let characterIndex = textView.characterIndexForInsertion(at: point)
+			if characterIndex < textView.string.count {
+				onClickCharacter(characterIndex)
+			}
+		}
+	}
+}