From 543dde0de2e4de309801fbed92bc043ef6b47e31 Mon Sep 17 00:00:00 2001
From: Rosalie Wanders <rosalie@mailbox.org>
Date: Tue, 16 Sep 2025 22:07:56 +0200
Subject: [PATCH] RMG: don't allow drag & drop events while ROM is being opened

---
 Source/RMG/UserInterface/MainWindow.cpp | 13 ++++++++++---
 Source/RMG/UserInterface/MainWindow.hpp |  2 +-
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/Source/RMG/UserInterface/MainWindow.cpp b/Source/RMG/UserInterface/MainWindow.cpp
index bdd06aef..bdd1cb7f 100644
--- a/Source/RMG/UserInterface/MainWindow.cpp
+++ b/Source/RMG/UserInterface/MainWindow.cpp
@@ -680,7 +680,7 @@ void MainWindow::launchEmulationThread(QString cartRom, QString address, int por
     this->launchEmulationThread(cartRom, "", false, -1, true);
 }
 
-void MainWindow::launchEmulationThread(QString cartRom, QString diskRom, bool refreshRomListAfterEmulation, int slot, bool netplay)
+void MainWindow::launchEmulationThread(QString cartRom, QString diskRom, bool refreshRomListAfterEmulation, int slot, bool netplay, bool dragdrop)
 {
 #ifdef NETPLAY
     if (this->netplaySessionDialog != nullptr && !netplay)
@@ -690,7 +690,7 @@ void MainWindow::launchEmulationThread(QString cartRom, QString diskRom, bool re
     }
 #endif // NETPLAY
 
-    if (this->emulationThread->isRunning())
+    if (!dragdrop && this->emulationThread->isRunning())
     {
         this->showErrorMessage("EmulationThread::run Failed", "Cannot start emulation when emulation is already running or being started");
         return;
@@ -1435,6 +1435,13 @@ void MainWindow::on_EventFilter_FileDropped(QDropEvent *event)
     bool refreshRomList  = false;
     QString file;
 
+    // when we're still opening the ROM while emulation is running,
+    // ignore the event
+    if (this->emulationThread->isRunning() && !CoreHasRomOpen())
+    {
+        return;
+    }
+
     if (inEmulation && confirmDragDrop)
     {
         QMessageBox::StandardButton reply = QMessageBox::question(this, "",
@@ -1460,7 +1467,7 @@ void MainWindow::on_EventFilter_FileDropped(QDropEvent *event)
         refreshRomList = this->ui_RefreshRomListAfterEmulation;
     }
 
-    this->launchEmulationThread(file, "", refreshRomList);
+    this->launchEmulationThread(file, "", refreshRomList, -1, false, true);
 #endif // DRAG_DROP
 }
 
diff --git a/Source/RMG/UserInterface/MainWindow.hpp b/Source/RMG/UserInterface/MainWindow.hpp
index 79380a63..3c1a69f5 100644
--- a/Source/RMG/UserInterface/MainWindow.hpp
+++ b/Source/RMG/UserInterface/MainWindow.hpp
@@ -139,7 +139,7 @@ class MainWindow : public QMainWindow, private Ui::MainWindow
     void initializeEmulationThread(void);
     void connectEmulationThreadSignals(void);
     void launchEmulationThread(QString cartRom, QString address, int port, int player);
-    void launchEmulationThread(QString cartRom, QString diskRom = "", bool refreshRomListAfterEmulation = false, int slot = -1, bool netplay = false);
+    void launchEmulationThread(QString cartRom, QString diskRom = "", bool refreshRomListAfterEmulation = false, int slot = -1, bool netplay = false, bool dragdrop = false);
 
     QString getSaveStateSlotDateTimeText(QAction* action);
     QString getSaveStateSlotText(QAction* action, int slot);