oak-editor/app/widget/timelinewidget/timelinewidget.cpp

/***

  Olive - Non-Linear Video Editor
  Copyright (C) 2021 Olive Team

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.

***/

#include "timelinewidget.h"

#include <cfloat>
#include <QSplitter>
#include <QVBoxLayout>
#include <QtMath>

#include "core.h"
#include "common/range.h"
#include "common/timecodefunctions.h"
#include "dialog/nodeproperties/nodepropertiesdialog.h"
#include "dialog/sequence/sequence.h"
#include "dialog/speedduration/speeddurationdialog.h"
#include "node/block/transition/transition.h"
#include "tool/add.h"
#include "tool/beam.h"
#include "tool/edit.h"
#include "tool/pointer.h"
#include "tool/razor.h"
#include "tool/record.h"
#include "tool/ripple.h"
#include "tool/rolling.h"
#include "tool/slide.h"
#include "tool/slip.h"
#include "tool/transition.h"
#include "tool/zoom.h"
#include "tool/tool.h"
#include "trackview/trackview.h"
#include "undo/timelineundogeneral.h"
#include "undo/timelineundopointer.h"
#include "undo/timelineundoripple.h"
#include "undo/timelineundoworkarea.h"
#include "widget/menu/menu.h"
#include "widget/menu/menushared.h"
#include "widget/nodeview/nodeviewundo.h"

namespace olive {

#define super TimeBasedWidget

TimelineWidget::TimelineWidget(QWidget *parent) :
  super(true, true, parent),
  rubberband_(QRubberBand::Rectangle, this),
  active_tool_(nullptr),
  use_audio_time_units_(false),
  subtitle_show_command_(nullptr)
{
  QVBoxLayout* vert_layout = new QVBoxLayout(this);
  vert_layout->setSpacing(0);
  vert_layout->setMargin(0);

  QHBoxLayout* ruler_and_time_layout = new QHBoxLayout();
  vert_layout->addLayout(ruler_and_time_layout);

  timecode_label_ = new RationalSlider();
  timecode_label_->SetAlignment(Qt::AlignCenter);
  timecode_label_->SetDisplayType(RationalSlider::kTime);
  timecode_label_->setVisible(false);
  connect(timecode_label_, &RationalSlider::ValueChanged, this, &TimelineWidget::SetTimeAndSignal);
  ruler_and_time_layout->addWidget(timecode_label_);

  ruler_and_time_layout->addWidget(ruler());
  ruler()->SetSnapService(this);

  // Create list of TimelineViews - these MUST correspond to the ViewType enum

  view_splitter_ = new QSplitter(Qt::Vertical);
  vert_layout->addWidget(view_splitter_);

  // Video view
  views_.append(new TimelineAndTrackView(Qt::AlignBottom));

  // Audio view
  views_.append(new TimelineAndTrackView(Qt::AlignTop));

  // Subtitle view
  views_.append(new TimelineAndTrackView(Qt::AlignTop));

  // Create tools
  tools_.resize(olive::Tool::kCount);
  tools_.fill(nullptr);

  tools_.replace(olive::Tool::kPointer, new PointerTool(this));
  tools_.replace(olive::Tool::kEdit, new EditTool(this));
  tools_.replace(olive::Tool::kRipple, new RippleTool(this));
  tools_.replace(olive::Tool::kRolling, new RollingTool(this));
  tools_.replace(olive::Tool::kRazor, new RazorTool(this));
  tools_.replace(olive::Tool::kSlip, new SlipTool(this));
  tools_.replace(olive::Tool::kSlide, new SlideTool(this));
  tools_.replace(olive::Tool::kZoom, new ZoomTool(this));
  tools_.replace(olive::Tool::kTransition, new TransitionTool(this));
  tools_.replace(olive::Tool::kRecord, new RecordTool(this));
  tools_.replace(olive::Tool::kAdd, new AddTool(this));

  import_tool_ = new ImportTool(this);

  // We add this to the list to make deleting all tools easier, it should never get accessed through the list under
  // normal circumstances (but *technically* its index would be Tool::kCount)
  tools_.append(import_tool_);

  // Global scrollbar
  connect(scrollbar(), &QScrollBar::valueChanged, ruler(), &TimeRuler::SetScroll);
  connect(views_.first()->view()->horizontalScrollBar(), &QScrollBar::rangeChanged, scrollbar(), &QScrollBar::setRange);
  vert_layout->addWidget(scrollbar());

  foreach (TimelineAndTrackView* tview, views_) {
    TimelineView* view = tview->view();

    view->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    view->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
    view->SetSnapService(this);
    view->SetSelectionList(&selections_);
    view->SetGhostList(&ghost_items_);

    view_splitter_->addWidget(tview);

    ConnectTimelineView(view, false);

    connect(view->horizontalScrollBar(), &QScrollBar::valueChanged, ruler(), &TimeRuler::SetScroll);
    connect(view, &TimelineView::ScaleChanged, this, &TimelineWidget::SetScale);
    connect(view, &TimelineView::TimeChanged, this, &TimelineWidget::SetTimeAndSignal);
    connect(view, &TimelineView::customContextMenuRequested, this, &TimelineWidget::ShowContextMenu);
    connect(scrollbar(), &QScrollBar::valueChanged, view->horizontalScrollBar(), &QScrollBar::setValue);
    connect(view->horizontalScrollBar(), &QScrollBar::valueChanged, scrollbar(), &QScrollBar::setValue);

    connect(view, &TimelineView::MousePressed, this, &TimelineWidget::ViewMousePressed);
    connect(view, &TimelineView::MouseMoved, this, &TimelineWidget::ViewMouseMoved);
    connect(view, &TimelineView::MouseReleased, this, &TimelineWidget::ViewMouseReleased);
    connect(view, &TimelineView::MouseDoubleClicked, this, &TimelineWidget::ViewMouseDoubleClicked);
    connect(view, &TimelineView::DragEntered, this, &TimelineWidget::ViewDragEntered);
    connect(view, &TimelineView::DragMoved, this, &TimelineWidget::ViewDragMoved);
    connect(view, &TimelineView::DragLeft, this, &TimelineWidget::ViewDragLeft);
    connect(view, &TimelineView::DragDropped, this, &TimelineWidget::ViewDragDropped);

    connect(tview->splitter(), &QSplitter::splitterMoved, this, &TimelineWidget::UpdateHorizontalSplitters);

    // Connect each view's scroll to each other
    foreach (TimelineAndTrackView* other_tview, views_) {
      TimelineView* other_view = other_tview->view();

      if (view != other_view) {
        connect(view->horizontalScrollBar(), &QScrollBar::valueChanged, other_view->horizontalScrollBar(), &QScrollBar::setValue);
      }
    }
  }

  // Split viewer 50/50
  QList<int> view_sizes;
  view_sizes.reserve(views_.size());
  view_sizes.append(height()/2);  // Video
  view_sizes.append(height()/2);  // Audio
  view_sizes.append(0);           // Subtitle (hidden by default)
  view_splitter_->setSizes(view_sizes);

  // Video and audio are not collapsible, subtitle is
  view_splitter_->setCollapsible(Track::kVideo, false);
  view_splitter_->setCollapsible(Track::kAudio, false);
  view_splitter_->setCollapsible(Track::kSubtitle, true);

  // FIXME: Magic number
  SetScale(90.0);

  SetAutoSetTimebase(false);

  connect(Core::instance(), &Core::ToolChanged, this, &TimelineWidget::ToolChanged);
  connect(Core::instance(), &Core::AddableObjectChanged, this, &TimelineWidget::AddableObjectChanged);
}

TimelineWidget::~TimelineWidget()
{
  // Ensure no blocks are selected before any child widgets are destroyed (prevents corrupt ViewSelectionChanged() signal)
  ConnectViewerNode(nullptr);

  Clear();

  qDeleteAll(tools_);

  delete subtitle_show_command_;
}

void TimelineWidget::Clear()
{
  // Emit that we've deselected any selected blocks
  SignalDeselectedAllBlocks();

  // Set null timebase
  SetTimebase(0);
}

void TimelineWidget::TimebaseChangedEvent(const rational &timebase)
{
  super::TimebaseChangedEvent(timebase);

  timecode_label_->SetTimebase(timebase);

  timecode_label_->setVisible(!timebase.isNull());

  UpdateViewTimebases();
}

void TimelineWidget::resizeEvent(QResizeEvent *event)
{
  super::resizeEvent(event);

  // Update timecode label size
  UpdateTimecodeWidthFromSplitters(views_.first()->splitter());
}

void TimelineWidget::TimeChangedEvent(const rational &time)
{
  super::TimeChangedEvent(time);

  SetViewTime(time);

  timecode_label_->SetValue(time);
}

void TimelineWidget::ScaleChangedEvent(const double &scale)
{
  super::ScaleChangedEvent(scale);

  foreach (TimelineAndTrackView* view, views_) {
    view->view()->SetScale(scale);
  }
}

void TimelineWidget::ConnectNodeEvent(ViewerOutput *n)
{
  Sequence* s = static_cast<Sequence*>(n);

  connect(s, &Sequence::TrackAdded, this, &TimelineWidget::AddTrack);
  connect(s, &Sequence::TrackRemoved, this, &TimelineWidget::RemoveTrack);
  connect(s, &Sequence::FrameRateChanged, this, &TimelineWidget::FrameRateChanged);
  connect(s, &Sequence::SampleRateChanged, this, &TimelineWidget::SampleRateChanged);

  ruler()->SetPlaybackCache(n->video_frame_cache());

  SetTimebase(n->GetVideoParams().frame_rate_as_time_base());

  for (int i=0;i<views_.size();i++) {
    Track::Type track_type = static_cast<Track::Type>(i);
    TimelineView* view = views_.at(i)->view();
    TrackList* track_list = s->track_list(track_type);
    TrackView* track_view = views_.at(i)->track_view();

    track_view->ConnectTrackList(track_list);
    view->ConnectTrackList(track_list);

    // Defer to the track to make all the block UI items necessary
    const QVector<Track*> tracks = s->track_list(track_type)->GetTracks();
    foreach (Track* track, tracks) {
      AddTrack(track);
    }
  }
}

void TimelineWidget::DisconnectNodeEvent(ViewerOutput *n)
{
  Sequence* s = static_cast<Sequence*>(n);

  disconnect(s, &Sequence::TrackAdded, this, &TimelineWidget::AddTrack);
  disconnect(s, &Sequence::TrackRemoved, this, &TimelineWidget::RemoveTrack);
  disconnect(s, &Sequence::FrameRateChanged, this, &TimelineWidget::FrameRateChanged);
  disconnect(s, &Sequence::SampleRateChanged, this, &TimelineWidget::SampleRateChanged);

  DeselectAll();

  foreach (Track* track, s->GetTracks()) {
    RemoveTrack(track);
  }

  ruler()->SetPlaybackCache(nullptr);

  SetTimebase(0);

  Clear();

  foreach (TimelineAndTrackView* tview, views_) {
    tview->track_view()->DisconnectTrackList();
    tview->view()->ConnectTrackList(nullptr);
  }
}

void TimelineWidget::CopyNodesToClipboardInternal(QXmlStreamWriter *writer, const QVector<Node *> &nodes, void* userdata)
{
  // Cache the earliest in point so all copied clips have a "relative" in point that can be pasted anywhere
  QVector<Block*>& selected = *static_cast<QVector<Block*>*>(userdata);
  rational earliest_in = RATIONAL_MAX;

  foreach (Block* block, selected) {
    earliest_in = qMin(earliest_in, block->in());
  }

  foreach (Block* block, selected) {
    writer->writeStartElement(QStringLiteral("block"));

    writer->writeAttribute(QStringLiteral("ptr"), QString::number(reinterpret_cast<quintptr>(block)));
    writer->writeAttribute(QStringLiteral("in"), (block->in() - earliest_in).toString());

    Track* track = block->track();
    writer->writeAttribute(QStringLiteral("tracktype"), QString::number(track->type()));
    writer->writeAttribute(QStringLiteral("trackindex"), QString::number(track->Index()));

    writer->writeEndElement();
  }
}

void TimelineWidget::PasteNodesFromClipboardInternal(QXmlStreamReader *reader, XMLNodeData& xml_node_data, void *userdata)
{
  QVector<BlockPasteData>& paste_data = *static_cast<QVector<BlockPasteData>*>(userdata);

  while (XMLReadNextStartElement(reader)) {
    if (reader->name() == QStringLiteral("block")) {
      BlockPasteData bpd;

      foreach (QXmlStreamAttribute attr, reader->attributes()) {
        if (attr.name() == QStringLiteral("ptr")) {
          bpd.block = static_cast<Block*>(xml_node_data.node_ptrs.value(attr.value().toULongLong()));
        } else if (attr.name() == QStringLiteral("in")) {
          bpd.in = rational::fromString(attr.value().toString());
        } else if (attr.name() == QStringLiteral("tracktype")) {
          bpd.track_type = static_cast<Track::Type>(attr.value().toInt());
        } else if (attr.name() == QStringLiteral("trackindex")) {
          bpd.track_index = attr.value().toInt();
        }
      }

      paste_data.append(bpd);

      reader->skipCurrentElement();
    }
  }
}

void TimelineWidget::SelectAll()
{
  QVector<Block*> newly_selected_blocks;

  foreach (Block* block, added_blocks_) {
    if (!selected_blocks_.contains(block)) {
      newly_selected_blocks.append(block);
      AddSelection(block);
    }
  }

  SignalSelectedBlocks(newly_selected_blocks, false);
}

void TimelineWidget::DeselectAll()
{
  // Clear selections
  selections_.clear();

  // Update all viewports
  UpdateViewports();

  // Clear list and emit signal
  SignalDeselectedAllBlocks();
}

void TimelineWidget::RippleToIn()
{
  RippleTo(Timeline::kTrimIn);
}

void TimelineWidget::RippleToOut()
{
  RippleTo(Timeline::kTrimOut);
}

void TimelineWidget::EditToIn()
{
  EditTo(Timeline::kTrimIn);
}

void TimelineWidget::EditToOut()
{
  EditTo(Timeline::kTrimOut);
}

void TimelineWidget::SplitAtPlayhead()
{
  if (!GetConnectedNode()) {
    return;
  }

  const rational &playhead_time = GetTime();

  QVector<Block*> selected_blocks = GetSelectedBlocks();

  // Prioritize blocks that are selected and overlap the playhead
  QVector<Block*> blocks_to_split;
  QVector<bool> block_is_selected;

  bool some_blocks_are_selected = false;

  // Get all blocks at the playhead
  foreach (Track* track, sequence()->GetTracks()) {
    Block* b = track->BlockContainingTime(playhead_time);

    if (dynamic_cast<ClipBlock*>(b)) {
      bool selected = false;

      // See if this block is selected
      foreach (Block* item, selected_blocks) {
        if (item == b) {
          some_blocks_are_selected = true;
          selected = true;
          break;
        }
      }

      blocks_to_split.append(b);
      block_is_selected.append(selected);
    }
  }

  // If some blocks are selected, we prioritize those and don't split the blocks that aren't
  if (some_blocks_are_selected) {
    for (int i=0;i<block_is_selected.size();i++) {
      if (!block_is_selected.at(i)) {
        blocks_to_split.removeAt(i);
        block_is_selected.removeAt(i);
        i--;
      }
    }
  }

  if (!blocks_to_split.isEmpty()) {
    Core::instance()->undo_stack()->push(new BlockSplitPreservingLinksCommand(blocks_to_split, {playhead_time}));
  }
}

void TimelineWidget::ReplaceBlocksWithGaps(const QVector<Block *> &blocks,
                                           bool remove_from_graph,
                                           MultiUndoCommand *command,
                                           bool handle_transitions)
{
  foreach (Block* b, blocks) {
    if (dynamic_cast<GapBlock*>(b)) {
      // No point in replacing a gap with a gap, and TrackReplaceBlockWithGapCommand will clear
      // up any extraneous gaps
      continue;
    }

    Track* original_track = b->track();

    command->add_child(new TrackReplaceBlockWithGapCommand(original_track, b, handle_transitions));

    if (remove_from_graph) {
      command->add_child(new NodeRemoveWithExclusiveDependenciesAndDisconnect(b));
    }
  }
}

void TimelineWidget::DeleteSelected(bool ripple)
{
  if (ruler()->GetActiveTimelineMarkers().size() > 0) {
    ruler()->DeleteSelected();
    return;
  }
  QVector<Block*> selected_list = GetSelectedBlocks();
  QVector<Block*> blocks_to_delete;

  foreach (Block* b, selected_list) {
    blocks_to_delete.append(b);
  }

  // No-op if nothing is selected
  if (blocks_to_delete.isEmpty()) {
    return;
  }

  MultiUndoCommand* command = new MultiUndoCommand();

  QVector<Block*> clips_to_delete;
  QVector<TransitionBlock*> transitions_to_delete;

  foreach (Block* b, blocks_to_delete) {
    if (dynamic_cast<ClipBlock*>(b)) {
      clips_to_delete.append(b);
    } else if (dynamic_cast<TransitionBlock*>(b)) {
      transitions_to_delete.append(static_cast<TransitionBlock*>(b));
    }
  }

  // For transitions, remove them but extend their attached blocks to fill their place
  foreach (TransitionBlock* transition, transitions_to_delete) {
    command->add_child(new TransitionRemoveCommand(transition, true));
  }

  // Replace clips with gaps (effectively deleting them)
  ReplaceBlocksWithGaps(clips_to_delete, true, command);

  // Remove all selections
  command->add_child(new SetSelectionsCommand(this, TimelineWidgetSelections(), GetSelections(), false));

  // Insert ripple command now that it's all cleaned up gaps
  if (ripple) {
    TimeRangeList range_list;

    foreach (Block* b, blocks_to_delete) {
      range_list.insert(TimeRange(b->in(), b->out()));
    }

    command->add_child(new TimelineRippleDeleteGapsAtRegionsCommand(sequence(), range_list));
  }

  Core::instance()->undo_stack()->pushIfHasChildren(command);

  // Ensures any current drag operations are cancelled
  ClearGhosts();
}

void TimelineWidget::IncreaseTrackHeight()
{
  if (!GetConnectedNode()) {
    return;
  }

  // Increase the height of each track by one "unit"
  foreach (Track* t, sequence()->GetTracks()) {
    t->SetTrackHeight(t->GetTrackHeight() + Track::kTrackHeightInterval);
  }
}

void TimelineWidget::DecreaseTrackHeight()
{
  if (!GetConnectedNode()) {
    return;
  }

  // Decrease the height of each track by one "unit"
  foreach (Track* t, sequence()->GetTracks()) {
    t->SetTrackHeight(qMax(t->GetTrackHeight() - Track::kTrackHeightInterval, Track::kTrackHeightMinimum));
  }
}

void TimelineWidget::InsertFootageAtPlayhead(const QVector<ViewerOutput*>& footage)
{
  import_tool_->PlaceAt(footage, GetTime(), true);
}

void TimelineWidget::OverwriteFootageAtPlayhead(const QVector<ViewerOutput *> &footage)
{
  import_tool_->PlaceAt(footage, GetTime(), false);
}

void TimelineWidget::ToggleLinksOnSelected()
{
  QVector<Node*> blocks;
  bool link = true;

  foreach (Block* item, GetSelectedBlocks()) {
    // Only clips can be linked
    if (!dynamic_cast<ClipBlock*>(item)) {
      continue;
    }

    // Prioritize unlinking, if any block has links, assume we're unlinking
    if (link && item->HasLinks()) {
      link = false;
    }

    blocks.append(item);
  }

  if (blocks.isEmpty()) {
    return;
  }

  Core::instance()->undo_stack()->push(new NodeLinkManyCommand(blocks, link));
}

void TimelineWidget::CopySelected(bool cut)
{
  if (!GetConnectedNode()) {
    return;
  }

  QVector<Block*> selected = GetSelectedBlocks();

  if (selected.isEmpty()) {
    return;
  }

  QVector<Node*> selected_nodes;

  foreach (Block* block, selected) {
    selected_nodes.append(block);

    QVector<Node*> deps = block->GetDependencies();

    foreach (Node* d, deps) {
      if (!selected_nodes.contains(d)) {
        selected_nodes.append(d);
      }
    }
  }

  CopyNodesToClipboard(selected_nodes, &selected);

  if (cut) {
    DeleteSelected();
  }
}

void TimelineWidget::Paste(bool insert)
{
  if (!GetConnectedNode()) {
    return;
  }

  MultiUndoCommand* command = new MultiUndoCommand();

  QVector<BlockPasteData> paste_data;
  QVector<Node*> pasted = PasteNodesFromClipboard(GetConnectedNode()->parent(), command, &paste_data);

  rational paste_start = GetTime();

  if (insert) {
    rational paste_end = GetTime();

    foreach (const BlockPasteData& bpd, paste_data) {
      paste_end = qMax(paste_end, paste_start + bpd.in + bpd.block->length());
    }

    if (paste_end != paste_start) {
      InsertGapsAt(paste_start, paste_end - paste_start, command);
    }
  }

  foreach (const BlockPasteData& bpd, paste_data) {
    qDebug() << "Placing" << bpd.block;
    command->add_child(new TrackPlaceBlockCommand(sequence()->track_list(bpd.track_type),
                                                  bpd.track_index,
                                                  bpd.block,
                                                  paste_start + bpd.in));
  }

  Core::instance()->undo_stack()->pushIfHasChildren(command);
}

void TimelineWidget::DeleteInToOut(bool ripple)
{
  if (!GetConnectedNode()
      || !GetConnectedNode()->GetTimelinePoints()->workarea()->enabled()) {
    return;
  }

  MultiUndoCommand* command = new MultiUndoCommand();

  if (ripple) {

    command->add_child(new TimelineRippleRemoveAreaCommand(
                         sequence(),
                         GetConnectedNode()->GetTimelinePoints()->workarea()->in(),
                         GetConnectedNode()->GetTimelinePoints()->workarea()->out()));

  } else {
    QVector<Track*> unlocked_tracks = sequence()->GetUnlockedTracks();

    foreach (Track* track, unlocked_tracks) {
      GapBlock* gap = new GapBlock();

      gap->set_length_and_media_out(GetConnectedNode()->GetTimelinePoints()->workarea()->length());

      command->add_child(new NodeAddCommand(static_cast<NodeGraph*>(track->parent()),
                                            gap));

      command->add_child(new TrackPlaceBlockCommand(sequence()->track_list(track->type()),
                                                    track->Index(),
                                                    gap,
                                                    GetConnectedNode()->GetTimelinePoints()->workarea()->in()));
    }
  }

  // Clear workarea after this
  command->add_child(new WorkareaSetEnabledCommand(GetConnectedNode()->project(),
                                                   GetConnectedNode()->GetTimelinePoints(),
                                                   false));

  if (ripple) {
    SetTimeAndSignal(GetConnectedNode()->GetTimelinePoints()->workarea()->in());
  }

  Core::instance()->undo_stack()->push(command);
}

void TimelineWidget::ToggleSelectedEnabled()
{
  QVector<Block*> items = GetSelectedBlocks();

  if (items.isEmpty()) {
    return;
  }

  MultiUndoCommand* command = new MultiUndoCommand();

  foreach (Block* i, items) {
    command->add_child(new BlockEnableDisableCommand(i,
                                                     !i->is_enabled()));
  }

  Core::instance()->undo_stack()->pushIfHasChildren(command);
}

void TimelineWidget::SetColorLabel(int index)
{
  MultiUndoCommand *command = new MultiUndoCommand();

  foreach (Block* b, selected_blocks_) {
    command->add_child(new NodeOverrideColorCommand(b, index));
  }

  Core::instance()->undo_stack()->push(command);
}

void TimelineWidget::NudgeLeft()
{
  if (GetConnectedNode()) {
    NudgeInternal(-timebase());
  }
}

void TimelineWidget::NudgeRight()
{
  if (GetConnectedNode()) {
    NudgeInternal(timebase());
  }
}

void TimelineWidget::MoveInToPlayhead()
{
  MoveToPlayheadInternal(false);
}

void TimelineWidget::MoveOutToPlayhead()
{
  MoveToPlayheadInternal(true);
}

void TimelineWidget::ShowSpeedDurationDialogForSelectedClips()
{
  QVector<ClipBlock*> clips;

  foreach (Block *b, selected_blocks_) {
    ClipBlock *c = dynamic_cast<ClipBlock*>(b);
    if (c) {
      clips.append(c);
    }
  }

  if (!clips.isEmpty()) {
    SpeedDurationDialog sdd(clips, timebase(), this);
    sdd.exec();
  }
}

void TimelineWidget::InsertGapsAt(const rational &earliest_point, const rational &insert_length, MultiUndoCommand *command)
{
  for (int i=0;i<Track::kCount;i++) {
    command->add_child(new TrackListInsertGaps(sequence()->track_list(static_cast<Track::Type>(i)),
                                               earliest_point,
                                               insert_length));
  }
}

Track *TimelineWidget::GetTrackFromReference(const Track::Reference &ref) const
{
  return sequence()->track_list(ref.type())->GetTrackAt(ref.index());
}

int TimelineWidget::GetTrackY(const Track::Reference &ref)
{
  return views_.at(ref.type())->view()->GetTrackY(ref.index());
}

int TimelineWidget::GetTrackHeight(const Track::Reference &ref)
{
  return views_.at(ref.type())->view()->GetTrackHeight(ref.index());
}

void TimelineWidget::CenterOn(qreal scene_pos)
{
  scrollbar()->setValue(qRound(scene_pos - scrollbar()->width()/2));
}

void TimelineWidget::ClearGhosts()
{
  if (!ghost_items_.isEmpty()) {
    foreach (TimelineViewGhostItem* ghost, ghost_items_) {
      delete ghost;
    }

    ghost_items_.clear();
  }

  HideSnaps();
}

TimelineTool *TimelineWidget::GetActiveTool()
{
  return tools_.at(Core::instance()->tool());
}

void TimelineWidget::ViewMousePressed(TimelineViewMouseEvent *event)
{
  active_tool_ = GetActiveTool();

  if (GetConnectedNode() && active_tool_ != nullptr) {
    active_tool_->MousePress(event);
    UpdateViewports();
  }

  if (event->GetButton() != Qt::LeftButton) {
    // Suspend tool immediately if the cursor isn't the primary button
    active_tool_->MouseRelease(event);
    UpdateViewports();
    active_tool_ = nullptr;
  }
}

void TimelineWidget::ViewMouseMoved(TimelineViewMouseEvent *event)
{
  if (GetConnectedNode()) {
    if (active_tool_) {
      active_tool_->MouseMove(event);

      UpdateViewports();

      QMetaObject::invokeMethod(this, "CatchUpScrollToPoint", Qt::QueuedConnection,
                                Q_ARG(int, qRound(event->GetSceneX())));
    } else {
      // Mouse is not down, attempt a hover event
      TimelineTool* hover_tool = GetActiveTool();

      if (hover_tool) {
        hover_tool->HoverMove(event);
      }
    }
  }
}


void TimelineWidget::ViewMouseReleased(TimelineViewMouseEvent *event)
{
  if (active_tool_) {
    if (GetConnectedNode()) {
      active_tool_->MouseRelease(event);
      UpdateViewports();
    }

    active_tool_ = nullptr;
  }
}

void TimelineWidget::ViewMouseDoubleClicked(TimelineViewMouseEvent *event)
{
  // kHand tool will return nullptr
  if (!GetActiveTool()) {
    // Only kHand should return a nullptr
    Q_ASSERT(Core::instance()->tool() == olive::Tool::kHand);
    return;
  }
  if (GetConnectedNode()) {
    GetActiveTool()->MouseDoubleClick(event);
    UpdateViewports();
  }
}

void TimelineWidget::ViewDragEntered(TimelineViewMouseEvent *event)
{
  import_tool_->DragEnter(event);
  UpdateViewports();
}

void TimelineWidget::ViewDragMoved(TimelineViewMouseEvent *event)
{
  import_tool_->DragMove(event);
  UpdateViewports();
}

void TimelineWidget::ViewDragLeft(QDragLeaveEvent *event)
{
  import_tool_->DragLeave(event);
  UpdateViewports();
}

void TimelineWidget::ViewDragDropped(TimelineViewMouseEvent *event)
{
  import_tool_->DragDrop(event);
  UpdateViewports();
}

void TimelineWidget::AddBlock(Block *block)
{
  // Set up clip with view parameters (clip item will automatically size its rect accordingly)
  if (!added_blocks_.contains(block)) {
    connect(block, &Block::LinksChanged, this, &TimelineWidget::BlockUpdated);
    connect(block, &Block::LabelChanged, this, &TimelineWidget::BlockUpdated);
    connect(block, &Block::ColorChanged, this, &TimelineWidget::BlockUpdated);
    connect(block, &Block::EnabledChanged, this, &TimelineWidget::BlockUpdated);
    connect(block, &Block::PreviewChanged, this, &TimelineWidget::BlockUpdated);

    added_blocks_.append(block);
  }
}

void TimelineWidget::RemoveBlock(Block *block)
{
  // Disconnect all signals
  disconnect(block, &Block::LinksChanged, this, &TimelineWidget::BlockUpdated);
  disconnect(block, &Block::LabelChanged, this, &TimelineWidget::BlockUpdated);
  disconnect(block, &Block::ColorChanged, this, &TimelineWidget::BlockUpdated);
  disconnect(block, &Block::EnabledChanged, this, &TimelineWidget::BlockUpdated);
  disconnect(block, &Block::PreviewChanged, this, &TimelineWidget::BlockUpdated);

  // Take item from map
  added_blocks_.removeOne(block);

  // If selected, deselect it
  int select_index = selected_blocks_.indexOf(block);
  if (select_index > -1) {
    selected_blocks_.removeAt(select_index);
    RemoveSelection(block);

    SignalBlockSelectionChange();
  }
}

void TimelineWidget::AddTrack(Track *track)
{
  foreach (Block* b, track->Blocks()) {
    AddBlock(b);
  }

  connect(track, &Track::IndexChanged, this, &TimelineWidget::TrackUpdated);
  connect(track, &Track::IndexChanged, this, &TimelineWidget::TrackIndexChanged);
  connect(track, &Track::BlocksRefreshed, this, &TimelineWidget::TrackUpdated);
  connect(track, &Track::TrackHeightChangedInPixels, this, &TimelineWidget::TrackUpdated);
  connect(track, &Track::BlockAdded, this, &TimelineWidget::AddBlock);
  connect(track, &Track::BlockRemoved, this, &TimelineWidget::RemoveBlock);
}

void TimelineWidget::RemoveTrack(Track *track)
{
  disconnect(track, &Track::IndexChanged, this, &TimelineWidget::TrackUpdated);
  disconnect(track, &Track::IndexChanged, this, &TimelineWidget::TrackIndexChanged);
  disconnect(track, &Track::BlocksRefreshed, this, &TimelineWidget::TrackUpdated);
  disconnect(track, &Track::TrackHeightChangedInPixels, this, &TimelineWidget::TrackUpdated);
  disconnect(track, &Track::BlockAdded, this, &TimelineWidget::AddBlock);
  disconnect(track, &Track::BlockRemoved, this, &TimelineWidget::RemoveBlock);

  RemoveSelection(TimeRange(0, RATIONAL_MAX), track->ToReference());

  foreach (Block* b, track->Blocks()) {
    RemoveBlock(b);
  }
}

void TimelineWidget::TrackUpdated()
{
  UpdateViewports(static_cast<Track*>(sender())->type());
}

void TimelineWidget::BlockUpdated()
{
  UpdateViewports(static_cast<Block*>(sender())->track()->type());
}

void TimelineWidget::UpdateHorizontalSplitters()
{
  QSplitter* sender_splitter = static_cast<QSplitter*>(sender());

  foreach (TimelineAndTrackView* tview, views_) {
    QSplitter* recv_splitter = tview->splitter();

    if (recv_splitter != sender_splitter) {
      recv_splitter->blockSignals(true);
      recv_splitter->setSizes(sender_splitter->sizes());
      recv_splitter->blockSignals(false);
    }
  }

  UpdateTimecodeWidthFromSplitters(sender_splitter);
}

void TimelineWidget::UpdateTimecodeWidthFromSplitters(QSplitter* s)
{
  timecode_label_->setFixedWidth(s->sizes().first() + s->handleWidth());
}

void TimelineWidget::ShowContextMenu()
{
  Menu menu(this);

  QVector<Block*> selected = GetSelectedBlocks();

  if (!selected.isEmpty()) {
    MenuShared::instance()->AddItemsForEditMenu(&menu, true);

    menu.addSeparator();

    MenuShared::instance()->AddColorCodingMenu(&menu);

    menu.addSeparator();

    QAction* properties_action = menu.addAction(tr("Properties"));
    connect(properties_action, &QAction::triggered, this, [this](){
      QVector<Block*> block_items = GetSelectedBlocks();
      QVector<Node*> nodes;

      foreach (Block* i, block_items) {
        nodes.append(i);
      }

      NodePropertiesDialog npd(nodes, timebase(), this);
      npd.exec();
    });
  }

  if (selected.isEmpty()) {

    QAction* toggle_audio_units = menu.addAction(tr("Use Audio Time Units"));
    toggle_audio_units->setCheckable(true);
    toggle_audio_units->setChecked(use_audio_time_units_);
    connect(toggle_audio_units, &QAction::triggered, this, &TimelineWidget::SetUseAudioTimeUnits);

    QAction* show_waveforms = menu.addAction(tr("Show Waveforms"));
    show_waveforms->setCheckable(true);
    show_waveforms->setChecked(views_.first()->view()->GetShowWaveforms());
    connect(show_waveforms, &QAction::triggered, this, &TimelineWidget::SetViewWaveformsEnabled);

    QAction* scroll_zoom = views_.first()->view()->AddSetScrollZoomsByDefaultActionToMenu(&menu);
    connect(scroll_zoom, &QAction::triggered, this, &TimelineWidget::SetScrollZoomsByDefaultOnAllViews);

    menu.addSeparator();

    QAction* properties_action = menu.addAction(tr("Properties"));
    connect(properties_action, &QAction::triggered, this, &TimelineWidget::ShowSequenceDialog);
  }

  menu.exec(QCursor::pos());
}

void TimelineWidget::DeferredScrollAction()
{
  scrollbar()->setValue(deferred_scroll_value_);
}

void TimelineWidget::ShowSequenceDialog()
{
  if (!GetConnectedNode()) {
    return;
  }

  SequenceDialog sd(sequence(), SequenceDialog::kExisting, this);
  sd.exec();
}

void TimelineWidget::SetUseAudioTimeUnits(bool use)
{
  use_audio_time_units_ = use;

  // Update timebases
  UpdateViewTimebases();
}

void TimelineWidget::SetViewTime(const rational &time)
{
  for (int i=0;i<views_.size();i++) {
    TimelineAndTrackView* view = views_.at(i);
    view->view()->SetTime(time);
  }
}

void TimelineWidget::ToolChanged()
{
  HideSnaps();
  SetViewBeamCursor(TimelineCoordinate(0, Track::kNone, -1));
  SetViewTransitionOverlay(nullptr, nullptr);

  AddableObjectChanged();
}

void TimelineWidget::AddableObjectChanged()
{
  // Special cast for subtitle adding - ensure section is visible
  if (Core::instance()->tool() == Tool::kAdd && Core::instance()->GetSelectedAddableObject() == Tool::kAddableSubtitle) {
    if (!subtitle_show_command_) {
      // Determine if we need to do anything
      QList<int> sz = view_splitter_->sizes();
      bool should_adjust_splitter = (sz[Track::kSubtitle] == 0);
      bool should_add_sub_track = (sequence() && sequence()->track_list(Track::kSubtitle)->GetTrackCount() == 0);

      if (should_adjust_splitter || should_add_sub_track) {
        // Create command
        subtitle_show_command_ = new MultiUndoCommand();

        if (should_adjust_splitter) {
          sz[Track::kSubtitle] = height() / Track::kCount;
          subtitle_show_command_->add_child(new SetSplitterSizesCommand(view_splitter_, sz));
        }

        if (should_add_sub_track) {
          subtitle_show_command_->add_child(new TimelineAddTrackCommand(sequence()->track_list(Track::kSubtitle)));
        }

        subtitle_show_command_->redo_now();
      }
    }
  } else if (subtitle_show_command_) {
    subtitle_show_command_->undo_now();
    delete subtitle_show_command_;
    subtitle_show_command_ = nullptr;
  }
}

void TimelineWidget::SetViewWaveformsEnabled(bool e)
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->SetShowWaveforms(e);
  }
}

void TimelineWidget::FrameRateChanged()
{
  SetTimebase(GetConnectedNode()->GetVideoParams().frame_rate_as_time_base());
}

void TimelineWidget::SampleRateChanged()
{
  UpdateViewTimebases();
}

void TimelineWidget::TrackIndexChanged(int old, int now)
{
  Track* track = static_cast<Track*>(sender());

  Track::Reference old_ref(track->type(), old);
  Track::Reference new_ref(track->type(), now);

  auto track_selections = selections_.take(old_ref);
  if (!track_selections.isEmpty()) {
    selections_.insert(new_ref, track_selections);
  }
}

void TimelineWidget::SetScrollZoomsByDefaultOnAllViews(bool e)
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->SetScrollZoomsByDefault(e);
  }
}

void TimelineWidget::SignalBlockSelectionChange()
{
  emit BlockSelectionChanged(selected_blocks_);
}

void TimelineWidget::AddGhost(TimelineViewGhostItem *ghost)
{
  ghost_items_.append(ghost);

  UpdateViewports(ghost->GetTrack().type());
}

void TimelineWidget::UpdateViewTimebases()
{
  for (int i=0;i<views_.size();i++) {
    TimelineAndTrackView* view = views_.at(i);

    if (GetConnectedNode() && use_audio_time_units_ && i == Track::kAudio) {
      view->view()->SetTimebase(GetConnectedNode()->GetAudioParams().sample_rate_as_time_base());
    } else {
      view->view()->SetTimebase(timebase());
    }
  }
}

void TimelineWidget::NudgeInternal(const rational &amount)
{
  if (!selected_blocks_.isEmpty()) {
    MultiUndoCommand *command = new MultiUndoCommand();

    foreach (Block* b, selected_blocks_) {
      command->add_child(new TrackReplaceBlockWithGapCommand(b->track(), b, false));
      command->add_child(new TrackPlaceBlockCommand(sequence()->track_list(b->track()->type()), b->track()->Index(), b, b->in() + amount));
    }

    // Nudge selections
    TimelineWidgetSelections new_sel = GetSelections();
    new_sel.ShiftTime(amount);
    command->add_child(new TimelineWidget::SetSelectionsCommand(this, new_sel, GetSelections(), true));

    Core::instance()->undo_stack()->push(command);
  }
}

void TimelineWidget::MoveToPlayheadInternal(bool out)
{
  if (GetConnectedNode() && !selected_blocks_.isEmpty()) {
    MultiUndoCommand *command = new MultiUndoCommand();

    // Remove each block from the graph
    QHash<Track*, rational> earliest_pts;
    foreach (Block *b, selected_blocks_) {
      command->add_child(new TrackReplaceBlockWithGapCommand(b->track(), b, false));

      rational r = earliest_pts.value(b->track(), out ? RATIONAL_MIN : RATIONAL_MAX);
      rational compare = out ? b->out() : b->in();
      if ((compare < r) == !out) {
        earliest_pts.insert(b->track(), compare);
      }
    }

    foreach (Block *b, selected_blocks_) {
      rational shift_amt = GetTime() - earliest_pts.value(b->track());
      rational new_in = b->in() + shift_amt;
      bool can_shift = true;

      if (new_in < 0) {
        // Handle clips threatening to go below 0
        rational new_out = new_in + b->length();
        if (new_out <= 0) {
          can_shift = false;
        } else {
          command->add_child(new BlockResizeWithMediaInCommand(b, new_out));
          new_in = 0;
        }
      }

      if (can_shift) {
        command->add_child(new TrackPlaceBlockCommand(sequence()->track_list(b->track()->type()), b->track()->Index(), b, new_in));
      }
    }

    // Shift selections
    TimelineWidgetSelections new_sel = GetSelections();
    for (auto it=new_sel.begin(); it!=new_sel.end(); it++) {
      rational track_adj = GetTime() - earliest_pts.value(GetTrackFromReference(it.key()), GetTime());
      if (!track_adj.isNull()) {
        it.value().shift(track_adj);
      }
    }
    command->add_child(new SetSelectionsCommand(this, new_sel, GetSelections(), true));

    Core::instance()->undo_stack()->push(command);
  }
}

void TimelineWidget::SetViewBeamCursor(const TimelineCoordinate &coord)
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->SetBeamCursor(coord);
  }
}

void TimelineWidget::SetViewTransitionOverlay(ClipBlock *out, ClipBlock *in)
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->SetTransitionOverlay(out, in);
  }
}

void TimelineWidget::SetBlockLinksSelected(ClipBlock* block, bool selected)
{
  foreach (Block* link, block->block_links()) {
    if (selected) {
      AddSelection(link);
    } else {
      RemoveSelection(link);
    }
  }
}

void TimelineWidget::QueueScroll(int value)
{
  // (using a hacky singleShot so the scroll occurs after the scene and its scrollbars have updated)
  deferred_scroll_value_ = value;

  QTimer::singleShot(0, this, &TimelineWidget::DeferredScrollAction);
}

TimelineView *TimelineWidget::GetFirstTimelineView()
{
  return views_.first()->view();
}

rational TimelineWidget::GetTimebaseForTrackType(Track::Type type)
{
  return views_.at(type)->view()->timebase();
}

const QRect& TimelineWidget::GetRubberBandGeometry() const
{
  return rubberband_.geometry();
}

void TimelineWidget::SignalSelectedBlocks(QVector<Block *> input, bool filter)
{
  if (input.isEmpty()) {
    return;
  }

  if (filter) {
    // If filtering, remove all the blocks that are already selected
    for (int i=0; i<input.size(); i++) {
      Block* b = input.at(i);

      if (selected_blocks_.contains(b)) {
        input.removeAt(i);
        i--;
      }
    }
  }

  selected_blocks_.append(input);

  emit SignalBlockSelectionChange();
}

void TimelineWidget::SignalDeselectedBlocks(const QVector<Block *> &deselected_blocks)
{
  if (deselected_blocks.isEmpty()) {
    return;
  }

  foreach (Block* b, deselected_blocks) {
    selected_blocks_.removeOne(b);
  }

  emit SignalBlockSelectionChange();
}

void TimelineWidget::SignalDeselectedAllBlocks()
{
  if (!selected_blocks_.isEmpty()) {
    selected_blocks_.clear();
    SignalBlockSelectionChange();
  }
}

QVector<Timeline::EditToInfo> TimelineWidget::GetEditToInfo(const rational& playhead_time,
                                                            Timeline::MovementMode mode)
{
  // Get list of unlocked tracks
  QVector<Track*> tracks = sequence()->GetUnlockedTracks();

  // Create list to cache nearest times and the blocks at this point
  QVector<Timeline::EditToInfo> info_list(tracks.size());

  for (int i=0;i<tracks.size();i++) {
    Timeline::EditToInfo info;

    Track* track = tracks.at(i);
    info.track = track;

    Block* b;

    // Determine what block is at this time (for "trim in", we want to catch blocks that start at
    // the time, for "trim out" we don't)
    if (mode == Timeline::kTrimIn) {
      b = track->NearestBlockBeforeOrAt(playhead_time);
    } else {
      b = track->NearestBlockBefore(playhead_time);
    }

    // If we have a block here, cache how close it is to the track
    if (b) {
      rational this_track_closest_point;

      if (mode == Timeline::kTrimIn) {
        this_track_closest_point = b->in();
      } else {
        this_track_closest_point = b->out();
      }

      info.nearest_time = this_track_closest_point;
    }

    info.nearest_block = b;

    info_list[i] = info;
  }

  return info_list;
}

void TimelineWidget::RippleTo(Timeline::MovementMode mode)
{
  rational playhead_time = GetTime();

  QVector<Timeline::EditToInfo> tracks = GetEditToInfo(playhead_time, mode);

  if (tracks.isEmpty()) {
    return;
  }

  // Find each track's nearest point and determine the overall timeline's nearest point
  rational closest_point_to_playhead = (mode == Timeline::kTrimIn) ? 0 : RATIONAL_MAX;

  foreach (const Timeline::EditToInfo& info, tracks) {
    if (info.nearest_block) {
      if (mode == Timeline::kTrimIn) {
        closest_point_to_playhead = qMax(info.nearest_time, closest_point_to_playhead);
      } else {
        closest_point_to_playhead = qMin(info.nearest_time, closest_point_to_playhead);
      }
    }
  }

  // If we're not inserting gaps and the edit point is right on the nearest in point, we enter a
  // single-frame mode where we remove one frame only
  if (closest_point_to_playhead == playhead_time) {
    if (mode == Timeline::kTrimIn) {
      playhead_time += timebase();
    } else {
      playhead_time -= timebase();
    }
  }

  // For standard rippling, we can cache here the region that will be rippled out
  rational in_ripple = qMin(closest_point_to_playhead, playhead_time);
  rational out_ripple = qMax(closest_point_to_playhead, playhead_time);

  TimelineRippleRemoveAreaCommand* c = new TimelineRippleRemoveAreaCommand(sequence(),
                                                                           in_ripple,
                                                                           out_ripple);

  Core::instance()->undo_stack()->push(c);

  // If we rippled, ump to where new cut is if applicable
  if (mode == Timeline::kTrimIn) {
    SetTimeAndSignal(closest_point_to_playhead);
  } else if (mode == Timeline::kTrimOut && closest_point_to_playhead == GetTime()) {
    SetTimeAndSignal(playhead_time);
  }
}

void TimelineWidget::EditTo(Timeline::MovementMode mode)
{
  const rational playhead_time = GetTime();

  // Get list of unlocked tracks
  QVector<Timeline::EditToInfo> tracks = GetEditToInfo(playhead_time, mode);

  if (tracks.isEmpty()) {
    return;
  }

  MultiUndoCommand* command = new MultiUndoCommand();

  foreach (const Timeline::EditToInfo& info, tracks) {
    if (info.nearest_block
        && !dynamic_cast<GapBlock*>(info.nearest_block)
        && info.nearest_time != playhead_time) {
      rational new_len;

      if (mode == Timeline::kTrimIn) {
        new_len = playhead_time - info.nearest_time;
      } else {
        new_len = info.nearest_time - playhead_time;
      }
      new_len = info.nearest_block->length() - new_len;

      command->add_child(new BlockTrimCommand(info.track,
                                              info.nearest_block,
                                              new_len,
                                              mode));
    }
  }

  Core::instance()->undo_stack()->pushIfHasChildren(command);
}

void TimelineWidget::ShowSnap(const QVector<rational> &times)
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->EnableSnap(times);
  }
}

void TimelineWidget::UpdateViewports(const Track::Type &type)
{
  if (type == Track::kNone) {
    foreach (TimelineAndTrackView* tview, views_) {
      tview->view()->viewport()->update();
    }
  } else {
    views_.at(type)->view()->viewport()->update();
  }
}

QVector<Block *> TimelineWidget::GetBlocksInGlobalRect(const QPoint &p1, const QPoint& p2)
{
  QVector<Block*> blocks_in_rect;

  // Determine which tracks are in the rect
  for (int i=0; i<views_.size(); i++) {
    TimelineView* view = views_.at(i)->view();

    // Map global mouse coordinates to viewport
    QRectF mapped_rect(view->mapToScene(view->viewport()->mapFromGlobal(p1)),
                       view->mapToScene(view->viewport()->mapFromGlobal(p2)));

    // Normalize
    mapped_rect = mapped_rect.normalized();

    // Get tracks
    TrackList* track_list = sequence()->track_list(static_cast<Track::Type>(i));

    for (int j=0; j<track_list->GetTrackCount(); j++) {
      int track_top = view->GetTrackY(j);
      int track_bottom = track_top + view->GetTrackHeight(j);

      if (!(track_bottom < mapped_rect.top() || track_top > mapped_rect.bottom())) {
        // This track is in the rect, so we'll iterate through its blocks and see where they start
        rational left_time = SceneToTime(mapped_rect.left());
        rational right_time = SceneToTime(mapped_rect.right(), true);

        Track* track = track_list->GetTrackAt(j);
        foreach (Block* b, track->Blocks()) {
          if (!(b->out() < left_time || b->in() > right_time)) {
            blocks_in_rect.append(b);
          }
        }
      }
    }
  }

  return blocks_in_rect;
}

QVector<Block *> TimelineWidget::GetBlocksInSelection(const TimelineWidgetSelections &sel)
{
  QVector<Block *> blocks;

  for (auto it=sel.cbegin(); it!=sel.cend(); it++) {
    const Track::Reference &ref = it.key();
    const TimeRangeList &list = it.value();

    for (const TimeRange &r : list) {
      Track *track = GetTrackFromReference(ref);
      if (track) {
        for (Block *b : track->Blocks()) {
          if (r.Contains(b->range())) {
            blocks.append(b);
          } else if (b->in() >= r.out()) {
            break;
          }
        }
      }
    }
  }

  return blocks;
}

void TimelineWidget::HideSnaps()
{
  foreach (TimelineAndTrackView* tview, views_) {
    tview->view()->DisableSnap();
  }
}

QByteArray TimelineWidget::SaveSplitterState() const
{
  return view_splitter_->saveState();
}

void TimelineWidget::RestoreSplitterState(const QByteArray &state)
{
  view_splitter_->restoreState(state);
}

void TimelineWidget::StartRubberBandSelect(const QPoint &global_cursor_start)
{
  drag_origin_ = global_cursor_start;

  // Start rubberband at origin
  QPoint local_origin = mapFromGlobal(drag_origin_);
  rubberband_.setGeometry(QRect(local_origin.x(), local_origin.y(), 0, 0));

  rubberband_.show();

  // We don't touch any blocks that are already selected. If you want these to be deselected by
  // default, call DeselectAll() before calling StartRubberBandSelect()
  rubberband_old_selections_ = selections_;
}

void TimelineWidget::MoveRubberBandSelect(bool enable_selecting, bool select_links)
{
  QPoint rubberband_now = QCursor::pos();

  rubberband_.setGeometry(QRect(mapFromGlobal(drag_origin_), mapFromGlobal(rubberband_now)).normalized());

  if (!enable_selecting) {
    return;
  }

  // Get current items in rubberband
  QVector<Block*> items_in_rubberband = GetBlocksInGlobalRect(drag_origin_, rubberband_now);

  // Reset selection to whatever it was before
  SetSelections(rubberband_old_selections_, false);

  // Add any blocks in rubberband
  rubberband_now_selected_.clear();

  foreach (Block* b, items_in_rubberband) {
    if (dynamic_cast<GapBlock*>(b)) {
      continue;
    }

    Track* t = b->track();
    if (t->IsLocked()) {
      continue;
    }

    if (!rubberband_now_selected_.contains(b)) {
      AddSelection(b);
      rubberband_now_selected_.append(b);
    }

    ClipBlock *c = dynamic_cast<ClipBlock*>(b);
    if (c && select_links) {
      foreach (Block* link, c->block_links()) {
        if (!rubberband_now_selected_.contains(link)) {
          AddSelection(link);
          rubberband_now_selected_.append(link);
        }
      }
    }
  }
}

void TimelineWidget::EndRubberBandSelect()
{
  rubberband_.hide();

  // Emit any blocks that were newly selected
  SignalSelectedBlocks(rubberband_now_selected_);

  rubberband_now_selected_.clear();
  rubberband_old_selections_.clear();
}

void TimelineWidget::AddSelection(const TimeRange &time, const Track::Reference &track)
{
  selections_[track].insert(time);

  UpdateViewports(track.type());
}

void TimelineWidget::AddSelection(Block *item)
{
  if (item->track()) {
    AddSelection(item->range(), item->track()->ToReference());
  }
}

void TimelineWidget::RemoveSelection(const TimeRange &time, const Track::Reference &track)
{
  selections_[track].remove(time);

  UpdateViewports(track.type());
}

void TimelineWidget::RemoveSelection(Block *item)
{
  if (item->track()) {
    RemoveSelection(item->range(), item->track()->ToReference());
  }
}

void TimelineWidget::SetSelections(const TimelineWidgetSelections &s, bool process_block_changes)
{
  if (selections_ == s) {
    return;
  }

  if (process_block_changes) {
    SignalDeselectedBlocks(GetBlocksInSelection(selections_.Subtracted(s)));
    SignalSelectedBlocks(GetBlocksInSelection(s.Subtracted(selections_)));
  }

  selections_ = s;

  UpdateViewports();
}

Block *TimelineWidget::GetItemAtScenePos(const TimelineCoordinate& coord)
{
  return views_.at(coord.GetTrack().type())->view()->GetItemAtScenePos(coord.GetFrame(), coord.GetTrack().index());
}

struct SnapData {
  rational time;
  rational movement;
};

QVector<SnapData> AttemptSnap(const QVector<double>& screen_pt,
                              double compare_pt,
                              const QVector<rational>& start_times,
                              const rational& compare_time) {
  const qreal kSnapRange = 10; // FIXME: Hardcoded number

  QVector<SnapData> snap_data;

  for (int i=0;i<screen_pt.size();i++) {
    // Attempt snapping to clip out point
    if (InRange(screen_pt.at(i), compare_pt, kSnapRange)) {
      snap_data.append({compare_time, compare_time - start_times.at(i)});
    }
  }

  return snap_data;
}

bool TimelineWidget::SnapPoint(QVector<rational> start_times, rational* movement, int snap_points)
{
  if (!GetConnectedNode()) {
    return false;
  }

  QVector<double> screen_pt;

  foreach (const rational& s, start_times) {
    screen_pt.append(TimeToScene(s + *movement));
  }

  QVector<SnapData> potential_snaps;

  if (snap_points & kSnapToPlayhead) {
    rational playhead_abs_time = GetTime();
    qreal playhead_pos = TimeToScene(playhead_abs_time);
    potential_snaps.append(AttemptSnap(screen_pt, playhead_pos, start_times, playhead_abs_time));
  }

  if (snap_points & kSnapToClips) {
    foreach (Block* b, added_blocks_) {
      qreal rect_left = TimeToScene(b->in());
      qreal rect_right = TimeToScene(b->out());

      // Attempt snapping to clip in point
      potential_snaps.append(AttemptSnap(screen_pt, rect_left, start_times, b->in()));

      // Attempt snapping to clip out point
      potential_snaps.append(AttemptSnap(screen_pt, rect_right, start_times, b->out()));
    }
  }

  if ((snap_points & kSnapToMarkers)) {
    foreach (TimelineMarker* m, GetConnectedNode()->GetTimelinePoints()->markers()->list()) {
      qreal marker_pos = TimeToScene(m->time().in());
      potential_snaps.append(AttemptSnap(screen_pt, marker_pos, start_times, m->time().in()));

      if (m->time().in() != m->time().out()) {
        marker_pos = TimeToScene(m->time().out());
        potential_snaps.append(AttemptSnap(screen_pt, marker_pos, start_times, m->time().out()));
      }
    }
  }

  if (potential_snaps.isEmpty()) {
    HideSnaps();
    return false;
  }

  int closest_snap = 0;
  rational closest_diff = qAbs(potential_snaps.at(0).movement - *movement);

  // Determine which snap point was the closest
  for (int i=1; i<potential_snaps.size(); i++) {
    rational this_diff = qAbs(potential_snaps.at(i).movement - *movement);

    if (this_diff < closest_diff) {
      closest_snap = i;
      closest_diff = this_diff;
    }
  }

  *movement = potential_snaps.at(closest_snap).movement;

  // Find all points at this movement
  QVector<rational> snap_times;
  foreach (const SnapData& d, potential_snaps) {
    if (d.movement == *movement) {
      snap_times.append(d.time);
    }
  }

  ShowSnap(snap_times);

  return true;
}

void TimelineWidget::SetSplitterSizesCommand::redo()
{
  old_sizes_ = splitter_->sizes();
  splitter_->setSizes(new_sizes_);
}

void TimelineWidget::SetSplitterSizesCommand::undo()
{
  splitter_->setSizes(old_sizes_);
}

}