From 912dcfdb3b05d35054ba939eb165355766bb03af Mon Sep 17 00:00:00 2001
From: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date: Fri, 13 May 2022 09:52:28 -0700
Subject: [PATCH] timeline: allow dropping on trackviewitem to overwrite at 0

Fixes #1928
---
 app/widget/timelinewidget/timelinewidget.cpp  |  5 +++++
 .../timelinewidget/trackview/trackview.cpp    |  3 +++
 .../timelinewidget/trackview/trackview.h      |  4 ++++
 .../trackview/trackviewitem.cpp               | 22 +++++++++++++++++++
 .../timelinewidget/trackview/trackviewitem.h  | 10 +++++++++
 .../view/timelineviewmouseevent.h             |  1 +
 6 files changed, 45 insertions(+)

diff --git a/app/widget/timelinewidget/timelinewidget.cpp b/app/widget/timelinewidget/timelinewidget.cpp
index 47c704a76..d46a35e9c 100644
--- a/app/widget/timelinewidget/timelinewidget.cpp
+++ b/app/widget/timelinewidget/timelinewidget.cpp
@@ -157,6 +157,11 @@ TimelineWidget::TimelineWidget(QWidget *parent) :
     connect(view, &TimelineView::DragLeft, this, &TimelineWidget::ViewDragLeft);
     connect(view, &TimelineView::DragDropped, this, &TimelineWidget::ViewDragDropped);
 
+    TrackView *tv = tview->track_view();
+    connect(tv, &TrackView::DragEntered, this, &TimelineWidget::ViewDragEntered);
+    connect(tv, &TrackView::DragLeft, this, &TimelineWidget::ViewDragLeft);
+    connect(tv, &TrackView::DragDropped, this, &TimelineWidget::ViewDragDropped);
+
     connect(tview->splitter(), &QSplitter::splitterMoved, this, &TimelineWidget::UpdateHorizontalSplitters);
 
     // Connect each view's scroll to each other
diff --git a/app/widget/timelinewidget/trackview/trackview.cpp b/app/widget/timelinewidget/trackview/trackview.cpp
index 562c68d55..09d2e0fbc 100644
--- a/app/widget/timelinewidget/trackview/trackview.cpp
+++ b/app/widget/timelinewidget/trackview/trackview.cpp
@@ -124,6 +124,9 @@ void TrackView::InsertTrack(Track *track)
   TrackViewItem *tvi = new TrackViewItem(track);
 
   connect(tvi, &TrackViewItem::AboutToDeleteTrack, this, &TrackView::AboutToDeleteTrack);
+  connect(tvi, &TrackViewItem::DragEntered, this, &TrackView::DragEntered);
+  connect(tvi, &TrackViewItem::DragLeft, this, &TrackView::DragLeft);
+  connect(tvi, &TrackViewItem::DragDropped, this, &TrackView::DragDropped);
 
   splitter_->Insert(track->Index(),
                     track->GetTrackHeightInPixels(),
diff --git a/app/widget/timelinewidget/trackview/trackview.h b/app/widget/timelinewidget/trackview/trackview.h
index 1498a526b..9d56dabe0 100644
--- a/app/widget/timelinewidget/trackview/trackview.h
+++ b/app/widget/timelinewidget/trackview/trackview.h
@@ -43,6 +43,10 @@ public:
 signals:
   void AboutToDeleteTrack(Track *track);
 
+  void DragEntered(TimelineViewMouseEvent* event);
+  void DragLeft(QDragLeaveEvent* event);
+  void DragDropped(TimelineViewMouseEvent* event);
+
 protected:
   virtual void resizeEvent(QResizeEvent *e) override;
 
diff --git a/app/widget/timelinewidget/trackview/trackviewitem.cpp b/app/widget/timelinewidget/trackview/trackviewitem.cpp
index 6a5ba698e..f3c254178 100644
--- a/app/widget/timelinewidget/trackview/trackviewitem.cpp
+++ b/app/widget/timelinewidget/trackview/trackviewitem.cpp
@@ -76,11 +76,33 @@ TrackViewItem::TrackViewItem(Track* track, QWidget *parent) :
 
   setMinimumHeight(mute_button_->height());
   setContextMenuPolicy(Qt::CustomContextMenu);
+  setAcceptDrops(true);
 
   connect(track, &Track::MutedChanged, mute_button_, &QPushButton::setChecked);
   connect(this, &QWidget::customContextMenuRequested, this, &TrackViewItem::ShowContextMenu);
 }
 
+void TrackViewItem::dragEnterEvent(QDragEnterEvent *event)
+{
+  TimelineViewMouseEvent e(0, 1, 1, track_->ToReference(), Qt::NoButton, event->keyboardModifiers());
+  e.SetMimeData(event->mimeData());
+  e.SetEvent(event);
+  emit DragEntered(&e);
+}
+
+void TrackViewItem::dragLeaveEvent(QDragLeaveEvent *event)
+{
+  emit DragLeft(event);
+}
+
+void TrackViewItem::dropEvent(QDropEvent *event)
+{
+  TimelineViewMouseEvent e(0, 1, 1, track_->ToReference(), Qt::NoButton, event->keyboardModifiers());
+  e.SetMimeData(event->mimeData());
+  e.SetEvent(event);
+  emit DragDropped(&e);
+}
+
 QPushButton *TrackViewItem::CreateMSLButton(const QColor& checked_color) const
 {
   QPushButton* button = new QPushButton();
diff --git a/app/widget/timelinewidget/trackview/trackviewitem.h b/app/widget/timelinewidget/trackview/trackviewitem.h
index 7ec2eb750..b4010cab0 100644
--- a/app/widget/timelinewidget/trackview/trackviewitem.h
+++ b/app/widget/timelinewidget/trackview/trackviewitem.h
@@ -28,6 +28,7 @@
 #include "node/output/track/track.h"
 #include "widget/clickablelabel/clickablelabel.h"
 #include "widget/focusablelineedit/focusablelineedit.h"
+#include "widget/timelinewidget/view/timelineviewmouseevent.h"
 
 namespace olive {
 
@@ -41,6 +42,15 @@ public:
 signals:
   void AboutToDeleteTrack(Track *track);
 
+  void DragEntered(TimelineViewMouseEvent* event);
+  void DragLeft(QDragLeaveEvent* event);
+  void DragDropped(TimelineViewMouseEvent* event);
+
+protected:
+  virtual void dragEnterEvent(QDragEnterEvent *event) override;
+  virtual void dragLeaveEvent(QDragLeaveEvent *event) override;
+  virtual void dropEvent(QDropEvent *event) override;
+
 private:
   QPushButton* CreateMSLButton(const QColor &checked_color) const;
 
diff --git a/app/widget/timelinewidget/view/timelineviewmouseevent.h b/app/widget/timelinewidget/view/timelineviewmouseevent.h
index 84cb3c0ba..babce9881 100644
--- a/app/widget/timelinewidget/view/timelineviewmouseevent.h
+++ b/app/widget/timelinewidget/view/timelineviewmouseevent.h
@@ -21,6 +21,7 @@
 #ifndef TIMELINEVIEWMOUSEEVENT_H
 #define TIMELINEVIEWMOUSEEVENT_H
 
+#include <QEvent>
 #include <QMimeData>
 #include <QPointF>
 #include <QPoint>