From ab738ea79d24744513f99f651b4fc201e655c0ff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mart=C3=ADn=20Lucas=20Golini?= <spartanj@gmail.com>
Date: Sat, 6 Dec 2025 12:28:35 -0300
Subject: [PATCH] Added `duplicate-line-or-selection` TextDocument command.
 Updated README.

---
 README.md                            |  4 +--
 include/eepp/ui/doc/textdocument.hpp |  2 ++
 src/eepp/ui/doc/textdocument.cpp     | 41 ++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 1bd4d0a60..f6520aca7 100644
--- a/README.md
+++ b/README.md
@@ -12,12 +12,10 @@ framework heavily focused on the development of rich graphical user interfaces.
 
 ### Cross platform functionality
 
-* Official support for Linux, Windows, macOS, Android and iOS.
+* Official support for Linux, Windows, macOS, FreeBSD, Haiku, Android and iOS.
 
 * Exports to HTML5 using emscripten with some minor limitations.
 
-* Also works on BSD and Haiku.
-
 ### UI Module
 
 * Base widgets to manage the app/game objects as nodes, with all basic input interaction events ( clicks, keypress, mouser over, focus, etc ).
diff --git a/include/eepp/ui/doc/textdocument.hpp b/include/eepp/ui/doc/textdocument.hpp
index 6b5a92f29..56563d0be 100644
--- a/include/eepp/ui/doc/textdocument.hpp
+++ b/include/eepp/ui/doc/textdocument.hpp
@@ -717,6 +717,8 @@ class EE_API TextDocument {
 
 	void joinLines();
 
+	void duplicateLineOrSelection();
+
 	void moveToNextParagraph();
 
 	void moveToPreviousParagraph();
diff --git a/src/eepp/ui/doc/textdocument.cpp b/src/eepp/ui/doc/textdocument.cpp
index 5d40e2938..f4100c2ba 100644
--- a/src/eepp/ui/doc/textdocument.cpp
+++ b/src/eepp/ui/doc/textdocument.cpp
@@ -4378,6 +4378,46 @@ void TextDocument::joinLines() {
 	mergeSelection();
 }
 
+void TextDocument::duplicateLineOrSelection() {
+	AtomicBoolScopedOp op( mRunningTransaction, true );
+
+	// Must process from bottom to top to not invalidate positions of cursors above.
+	for ( Int64 i = mSelection.size() - 1; i >= 0; --i ) {
+		TextRange sel = getSelectionIndex( i );
+
+		if ( sel.hasSelection() ) {
+			TextRange normalizedSel = sel.normalized();
+			String selectedText = getText( normalizedSel );
+			if ( !selectedText.empty() ) {
+				TextPosition insertionPoint = normalizedSel.end();
+				TextPosition endOfInsertion = insert( i, insertionPoint, selectedText );
+
+				// After duplicating selection, select the new duplicated text.
+				// The selection direction should be preserved.
+				if ( sel.isNormalized() ) {
+					setSelection( i, { insertionPoint, endOfInsertion } );
+				} else {
+					setSelection( i, { endOfInsertion, insertionPoint } );
+				}
+			}
+		} else {
+			Int64 lineNum = sel.start().line();
+			// Don't duplicate the last empty line.
+			if ( lineNum >= (Int64)linesCount() - 1 && getLineLength( lineNum ) <= 1 ) {
+				continue;
+			}
+
+			String lineText = getLineText( lineNum );
+			TextPosition insertionPoint = { lineNum + 1, 0 };
+			insert( i, insertionPoint, lineText );
+			TextPosition newCursorPos = { lineNum + 1, sel.start().column() };
+			setSelection( i, newCursorPos );
+		}
+	}
+
+	mergeSelection();
+}
+
 TextPosition TextDocument::findPreviousEmptyLines( size_t selIdx ) {
 	Int64 startLine = mSelection[selIdx].normalized().start().line() - 1;
 	bool found = false;
@@ -4625,6 +4665,7 @@ void TextDocument::initializeCommands() {
 	mCommands["from-base64"] = [this] { fromBase64(); };
 	mCommands["trim-trailing-whitespace"] = [this] { trimTrailingWhitespace(); };
 	mCommands["join-lines"] = [this] { joinLines(); };
+	mCommands["duplicate-line-or-selection"] = [this] { duplicateLineOrSelection(); };
 	mCommands["convert-indentation-to-tabs"] = [this] { convertIndentationToTabs(); };
 	mCommands["convert-indentation-to-spaces"] = [this] { convertIndentationToSpaces(); };