From 938ee55d42445d57fcdb501af43bb190be27f4b9 Mon Sep 17 00:00:00 2001
From: Adam Higerd <chighland@gmail.com>
Date: Tue, 19 Nov 2024 10:41:34 -0600
Subject: [PATCH] Qt: honor control characters in ScriptingTextBuffer::print

---
 .../qt/scripting/ScriptingTextBuffer.cpp      | 76 +++++++++++++++----
 .../qt/scripting/ScriptingTextBuffer.h        |  7 ++
 2 files changed, 67 insertions(+), 16 deletions(-)

diff --git a/src/platform/qt/scripting/ScriptingTextBuffer.cpp b/src/platform/qt/scripting/ScriptingTextBuffer.cpp
index da05bd2b9..c209adcd5 100644
--- a/src/platform/qt/scripting/ScriptingTextBuffer.cpp
+++ b/src/platform/qt/scripting/ScriptingTextBuffer.cpp
@@ -49,26 +49,70 @@ void ScriptingTextBuffer::setBufferName(const QString& name) {
 	emit bufferNameChanged(name);
 }
 
+void ScriptingTextBuffer::lineBreak() {
+	bool nextBlockExists = m_shim.cursor.movePosition(QTextCursor::NextBlock, QTextCursor::MoveAnchor, 1);
+	if (!nextBlockExists) {
+		m_shim.cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::MoveAnchor, 1);
+		m_shim.cursor.insertBlock();
+	}
+}
+
+void ScriptingTextBuffer::carriageReturn() {
+	m_shim.cursor.movePosition(QTextCursor::StartOfLine, QTextCursor::MoveAnchor, 1);
+}
+
+void ScriptingTextBuffer::tab() {
+	QTextCursor& cursor = m_shim.cursor;
+	int column = cursor.positionInBlock();
+	int move = tabStop - (column % tabStop) + 1;
+	if (column + move >= m_dims.width()) {
+		lineBreak();
+	} else if (column + move <= cursor.block().length()) {
+		cursor.movePosition(QTextCursor::Right, QTextCursor::MoveAnchor, move - 1);
+	} else {
+		move = column + move - cursor.block().length();
+		cursor.movePosition(QTextCursor::EndOfLine, QTextCursor::MoveAnchor, 1);
+		cursor.insertText(QString(move, ' '));
+	}
+}
+
+void ScriptingTextBuffer::insertString(const QString& text) {
+	QTextCursor& cursor = m_shim.cursor;
+	if (cursor.positionInBlock() >= m_dims.width()) {
+		lineBreak();
+	}
+	cursor.movePosition(QTextCursor::Right, QTextCursor::KeepAnchor, text.length());
+	cursor.insertText(text);
+}
+
 void ScriptingTextBuffer::print(const QString& text) {
 	QMutexLocker locker(&m_mutex);
-	for (QString split : text.split('\n')) {
-		while (m_shim.cursor.positionInBlock() + split.length() > m_dims.width()) {
-			int cut = m_dims.width() - m_shim.cursor.positionInBlock();
-			if (!m_shim.cursor.atBlockEnd()) {
-				m_shim.cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
-			}
-			m_shim.cursor.insertText(split.left(cut));
-			if (m_shim.cursor.atEnd()) {
-				m_shim.cursor.insertBlock();
-			} else {
-				m_shim.cursor.movePosition(QTextCursor::NextBlock, QTextCursor::MoveAnchor, 1);
-			}
-			split = split.mid(cut);
+
+	QTextCursor& cursor = m_shim.cursor;
+	QString toInsert;
+
+	for (const QChar& ch : text) {
+		int column = cursor.positionInBlock();
+		if (ch == '\t' || ch == '\n' || ch == '\r' || column + toInsert.length() >= m_dims.width()) {
+			insertString(toInsert);
+			toInsert.clear();
 		}
-		if (!m_shim.cursor.atBlockEnd()) {
-			m_shim.cursor.movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor, split.length());
+		switch (ch.unicode()) {
+			case '\t':
+				tab();
+				break;
+			case '\n':
+				lineBreak();
+				break;
+			case '\r':
+				carriageReturn();
+				break;
+			default:
+				toInsert += ch;
 		}
-		m_shim.cursor.insertText(split);
+	}
+	if (!toInsert.isEmpty()) {
+		insertString(toInsert);
 	}
 }
 
diff --git a/src/platform/qt/scripting/ScriptingTextBuffer.h b/src/platform/qt/scripting/ScriptingTextBuffer.h
index b4a9c5b83..717a5d284 100644
--- a/src/platform/qt/scripting/ScriptingTextBuffer.h
+++ b/src/platform/qt/scripting/ScriptingTextBuffer.h
@@ -36,6 +36,8 @@ signals:
 	void bufferNameChanged(const QString&);
 
 private:
+	enum { tabStop = 4 };
+
 	struct ScriptingBufferShim : public mScriptTextBuffer {
 		ScriptingTextBuffer* p;
 		QTextCursor cursor;
@@ -44,6 +46,11 @@ private:
 	QMutex m_mutex;
 	QString m_name;
 
+	void lineBreak();
+	void carriageReturn();
+	void tab();
+	void insertString(const QString& text);
+
 	static void init(struct mScriptTextBuffer*, const char* name);
 	static void deinit(struct mScriptTextBuffer*);