From c9501badec363d4c9ef9840ab476738c1c3f591d Mon Sep 17 00:00:00 2001
From: Binhao Qian <gonwan@gmail.com>
Date: Thu, 22 Jan 2026 14:05:50 +0800
Subject: [PATCH 1/2] Add dnd support.

---
 src/mainwindow.cpp | 31 +++++++++++++++++++++++++++++++
 src/mainwindow.h   |  2 ++
 2 files changed, 33 insertions(+)

diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index f610645a..84e6755d 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -29,6 +29,8 @@
 #include <QDesktopServices>
 #include <QDialog>
 #include <QDir>
+#include <QDragEnterEvent>
+#include <QDropEvent>
 #include <QEvent>
 #include <QFile>
 #include <QFileDialog>
@@ -41,6 +43,7 @@
 #include <QMenu>
 #include <QMenuBar>
 #include <QMessageBox>
+#include <QMimeData>
 #include <QObject>
 #include <QPixmap>
 #include <QPrinter>
@@ -104,6 +107,8 @@ MainWindow::MainWindow( const QStringList& arguments )
 	// UIC stuff
 	setupUi( this );
 
+	setAcceptDrops( true );
+
 	// Set up layout direction
 	if ( pConfig->m_advLayoutDirectionRL )
 		qApp->setLayoutDirection( Qt::RightToLeft );
@@ -608,6 +613,32 @@ void MainWindow::closeEvent( QCloseEvent* e )
 	QMainWindow::closeEvent( e );
 }
 
+void MainWindow::dragEnterEvent( QDragEnterEvent* e )
+{
+	if ( e->mimeData()->hasUrls() )
+		e->acceptProposedAction();
+	else
+		e->ignore();
+}
+
+void MainWindow::dropEvent( QDropEvent* e )
+{
+	if ( e->mimeData()->hasUrls() )
+	{
+		QUrl url = e->mimeData()->urls().first();
+
+		if ( url.isLocalFile() )
+		{
+			QString fileName = url.toLocalFile();
+
+			if ( fileName.endsWith( ".chm", Qt::CaseInsensitive ) || fileName.endsWith( ".epub", Qt::CaseInsensitive ) )
+				loadFile( fileName );
+		}
+
+		e->acceptProposedAction();
+	}
+}
+
 void MainWindow::printHelpAndExit()
 {
 	fprintf( stderr, "Usage: %s [options] [helpfile]\n"
diff --git a/src/mainwindow.h b/src/mainwindow.h
index ed847dce..c10f8c03 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -172,6 +172,8 @@ class MainWindow : public QMainWindow, public Ui::MainWindow
 	protected:
 		// Reimplemented functions
 		void        closeEvent( QCloseEvent* e );
+		void        dragEnterEvent( QDragEnterEvent* e );
+		void        dropEvent( QDropEvent* e );
 		bool        event( QEvent* e );
 
 	private:

From c99eefb2b74080ac0d5a579edf1a92a16de593d3 Mon Sep 17 00:00:00 2001
From: Binhao Qian <gonwan@gmail.com>
Date: Fri, 23 Jan 2026 06:43:15 +0800
Subject: [PATCH 2/2] Add checks when drag begin.

---
 src/mainwindow.cpp    | 19 ++++++++++++++++---
 src/viewwindowmgr.cpp |  1 +
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 84e6755d..72f6221f 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -616,9 +616,22 @@ void MainWindow::closeEvent( QCloseEvent* e )
 void MainWindow::dragEnterEvent( QDragEnterEvent* e )
 {
 	if ( e->mimeData()->hasUrls() )
-		e->acceptProposedAction();
-	else
-		e->ignore();
+	{
+		QUrl url = e->mimeData()->urls().first();
+
+		if ( url.isLocalFile() )
+		{
+			QString fileName = url.toLocalFile();
+
+			if ( fileName.endsWith( ".chm", Qt::CaseInsensitive ) || fileName.endsWith( ".epub", Qt::CaseInsensitive ) )
+			{
+				e->acceptProposedAction();
+				return;
+			}
+		}
+	}
+
+	e->ignore();
 }
 
 void MainWindow::dropEvent( QDropEvent* e )
diff --git a/src/viewwindowmgr.cpp b/src/viewwindowmgr.cpp
index 19630d84..288f4609 100644
--- a/src/viewwindowmgr.cpp
+++ b/src/viewwindowmgr.cpp
@@ -160,6 +160,7 @@ ViewWindow* ViewWindowMgr::current()
 ViewWindow* ViewWindowMgr::addNewTab( bool set_active )
 {
 	ViewWindow* browser = new ViewWindow( m_tabWidget );
+	browser->setAcceptDrops( false );
 
 	editFind->installEventFilter( this );