SongEditor.cpp

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/*
 * Hydrogen
 * Copyright(c) 2002-2008 by Alex >Comix< Cominu [comix@users.sourceforge.net]
 * Copyright(c) 2008-2025 The hydrogen development team [hydrogen-devel@lists.sourceforge.net]
 *
 * http://www.hydrogen-music.org
 *
 * 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 2 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 https://www.gnu.org/licenses
 *
 */
 
#include <assert.h>
#include <algorithm>
#include <memory>
 
#include <core/Basics/Song.h>
#include <core/Hydrogen.h>
#include <core/Basics/Pattern.h>
#include <core/Basics/PatternList.h>
#include <core/AudioEngine/AudioEngine.h>
#include <core/AudioEngine/TransportPosition.h>
#include <core/EventQueue.h>
#include <core/Helpers/Files.h>
#include <core/Basics/Instrument.h>
#include <core/Helpers/Xml.h>
#include <core/SoundLibrary/SoundLibraryDatabase.h>
using namespace H2Core;
 
#include "UndoActions.h"
#include "MainForm.h"
#include "SongEditor.h"
#include "SongEditorPanel.h"
#include "SongEditorPanelBpmWidget.h"
#include "SongEditorPanelTagWidget.h"
#include "PatternFillDialog.h"
#include "PlaybackTrackWaveDisplay.h"
#include "VirtualPatternDialog.h"
#include "SoundLibrary/SoundLibraryPanel.h"
#include "../Compatibility/DropEvent.h"
#include "../Compatibility/MouseEvent.h"
#include "../PatternEditor/PatternEditorPanel.h"
#include "../HydrogenApp.h"
#include "../CommonStrings.h"
#include "../InstrumentRack.h"
#include "../PatternPropertiesDialog.h"
#include "../SongPropertiesDialog.h"
#include "../Skin.h"
#include "../Widgets/FileDialog.h"
 
 
 
 
#ifdef WIN32
#include <time.h>
#include <windows.h>
#endif
 
struct PatternDisplayInfo {
        bool bActive;
        bool bNext;
        QString sPatternName;
};
 
 
SongEditor::SongEditor( QWidget *parent, QScrollArea *pScrollView, SongEditorPanel *pSongEditorPanel )
 : QWidget( parent )
 , m_bSequenceChanged( true )
 , m_pScrollView( pScrollView )
 , m_pSongEditorPanel( pSongEditorPanel )
 , m_selection( this )
 , m_pHydrogen( nullptr )
 , m_pAudioEngine( nullptr )
 , m_bEntered( false )
 , m_pBackgroundPixmap( nullptr )
 , m_pSequencePixmap( nullptr )
{
        m_pHydrogen = Hydrogen::get_instance();
        m_pAudioEngine = m_pHydrogen->getAudioEngine();
        
        Preferences* pPref = Preferences::get_instance();
        m_nMaxPatternColors = pPref->getMaxPatternColors(); // no need to
                                                                                                                // update this one.
 
        connect( HydrogenApp::get_instance(), &HydrogenApp::preferencesChanged, this, &SongEditor::onPreferencesChanged );
        connect( m_pScrollView->verticalScrollBar(), SIGNAL( valueChanged( int ) ), this, SLOT( scrolled( int ) ) );
        connect( m_pScrollView->horizontalScrollBar(), SIGNAL( valueChanged( int ) ), this, SLOT( scrolled( int ) ) );
 
        setAttribute(Qt::WA_OpaquePaintEvent);
        setFocusPolicy (Qt::StrongFocus);
 
        m_nGridWidth = pPref->getSongEditorGridWidth();
        m_nGridHeight = pPref->getSongEditorGridHeight();
 
        m_nCursorRow = 0;
        m_nCursorColumn = 0;
 
        int nInitialWidth = SongEditor::nMargin + pPref->getMaxBars() * m_nGridWidth;
 
        this->resize( QSize( nInitialWidth, m_nMinimumHeight ) );
 
        createBackground();     // create m_backgroundPixmap pixmap
 
        // Popup context menu
        m_pPopupMenu = new QMenu( this );
        m_pPopupMenu->addAction( tr( "&Cut" ), this, SLOT( cut() ) );
        m_pPopupMenu->addAction( tr( "&Copy" ), this, SLOT( copy() ) );
        m_pPopupMenu->addAction( tr( "&Paste" ), this, SLOT( paste() ) );
        m_pPopupMenu->addAction( tr( "&Delete" ), this, SLOT( deleteSelection() ) );
        m_pPopupMenu->addAction( tr( "Select &all" ), this, SLOT( selectAll() ) );
        m_pPopupMenu->addAction( tr( "Clear selection" ), this, SLOT( selectNone() ) );
        m_pPopupMenu->setObjectName( "SongEditorPopup" );
 
        HydrogenApp::get_instance()->addEventListener( this );
}
 
 
 
SongEditor::~SongEditor()
{
        if ( m_pBackgroundPixmap ) {
                delete m_pBackgroundPixmap;
        }
        if ( m_pSequencePixmap ) {
                delete m_pSequencePixmap;
        }
}
 

int SongEditor::yScrollTarget( QScrollArea *pScrollArea, int *pnPatternInView )
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        const int nScroll = pScrollArea->verticalScrollBar()->value();
        int nHeight = pScrollArea->height();
 
        auto pPlayingPatterns = m_pAudioEngine->getPlayingPatterns();
 
        // If no patterns are playing, no scrolling needed either.
        if ( pPlayingPatterns->size() == 0 ) {
                return nScroll;
        }
 
        m_pAudioEngine->lock( RIGHT_HERE );
 
        PatternList *pSongPatterns = pHydrogen->getSong()->getPatternList();
 
        // Duplicate the playing patterns vector before finding the pattern numbers of the playing patterns. This
        // avoids doing a linear search in the critical section.
        std::vector<Pattern *> currentPatterns;
        for ( int ii = 0; ii < pPlayingPatterns->size(); ++ii ) {
                currentPatterns.push_back( pPlayingPatterns->get( ii ) );
        }
        m_pAudioEngine->unlock();
 
        std::vector<int> playingRows;
        for ( Pattern *pPattern : currentPatterns ) {
                playingRows.push_back( pSongPatterns->index( pPattern ) );
        }
 
        // Occasionally the detection of playing patterns glitches at the
        // transition to empty columns.
        if ( playingRows.size() == 0 ) {
                return nScroll;
        }
 
        // Check if there are any currently playing patterns which are entirely visible.
        for ( int r : playingRows ) {
                if ( r * m_nGridHeight >= nScroll
                         && (r+1) * m_nGridHeight <= nScroll + nHeight) {
                        // Entirely visible. Our current scroll value is good.
                        if ( pnPatternInView ) {
                                *pnPatternInView = r;
                        }
                        return nScroll;
                }
        }
 
        // Find the maximum number of patterns that will fit in the viewport. We do this by sorting the playing
        // patterns on their row value, and traversing in order, considering each pattern in turn as visible just
        // at the bottom of the viewport. The pattern visible nearest the top of the viewport is tracked, and the
        // number of patterns visible in the viewport is given by the difference of the indices in the pattern
        // array.
        //
        // We track the maximum number of patterns visible, and record the patterns to scroll to differently
        // depending on whether the pattern is above or below the current viewport: for patterns above, we record
        // the topmost pattern in the maximal group, and for those below, record the bottommost pattern, as these
        // define the minimum amount of scrolling needed to fit the patterns in and don't want to scroll further
        // just to expose empty cells.
 
        std::sort( playingRows.begin(), playingRows.end() );
 
        int nTopIdx = 0;
        int nAboveMax = 0, nAbovePattern = -1, nAboveClosestPattern = -1,
                nBelowMax = 0, nBelowPattern = -1, nBelowClosestPattern = -1;
 
        for ( int nBottomIdx = 0; nBottomIdx < playingRows.size(); nBottomIdx++) {
                int nBottom = playingRows[ nBottomIdx ] * m_nGridHeight;
                int nTop;
                // Each bottom pattern is further down the list, so update the top pattern to track the top of the
                // viewport.
                for (;;) {
                        nTop = ( playingRows[ nTopIdx ] +1 ) * m_nGridHeight -1;
                        if ( nTop < nBottom - nHeight ) {
                                nTopIdx++;
                                assert( nTopIdx <= nBottomIdx && nTopIdx < playingRows.size() );
                        } else {
                                break;
                        }
                }
                int nPatternsInViewport = nBottomIdx - nTopIdx +1;
                if ( nBottom < nScroll ) {
                        // Above the viewport, accept any new maximal group, to find the maximal group closest to the
                        // current viewport.
                        if ( nPatternsInViewport >= nAboveMax ) {
                                nAboveMax = nPatternsInViewport;
                                // Above the viewport, we want to move only so far as to get the top pattern into the
                                // viewport. Record the top pattern.
                                nAbovePattern = playingRows[ nTopIdx ];
                                nAboveClosestPattern = playingRows[ nBottomIdx ];
                        }
                } else {
                        // Below the viewport, only accept a new maximal group if it's greater than the current maximal
                        // group.
                        if ( nPatternsInViewport > nBelowMax ) {
                                nBelowMax = nPatternsInViewport;
                                // Below the viewport, we want to scroll down to get the bottom pattern into view, so record
                                // the bottom pattern.
                                nBelowPattern = playingRows[ nBottomIdx ];
                                nBelowClosestPattern = playingRows[ nTopIdx ];
                        }
                }
        }
 
        // Pick between moving up, or moving down.
        int nAboveY = nAbovePattern * m_nGridHeight;
        int nBelowY = (nBelowPattern +1) * m_nGridHeight - nHeight;
        enum { Up, Down } direction = Down;
        if ( nAboveMax != 0) {
                if ( nAboveMax > nBelowMax ) {
                        // Move up to capture more active patterns
                        direction = Up;
                } else if ( nBelowMax > nAboveMax ) {
                        // Move down to capture more active patterns
                        direction = Down;
                } else {
                        // Tie-breaker. Which is closer?
                        assert( nAboveY <= nScroll &&  nScroll <= nBelowY );
                        if ( nScroll - nAboveY < nBelowY - nScroll ) {
                                direction = Up;
                        } else {
                                direction = Down;
                        }
                }
        } else {
                assert( nBelowMax != 0 );
                // Move down
                direction = Down;
        }
 
        if ( direction == Up ) {
                if ( pnPatternInView ) {
                        *pnPatternInView = nAboveClosestPattern;
                }
                return nAboveY;
        } else {
                if ( pnPatternInView ) {
                        *pnPatternInView = nBelowClosestPattern;
                }
                return nBelowY;
        }
}
 
 
int SongEditor::getGridWidth ()
{
        return m_nGridWidth;
}
 
 
 
void SongEditor::setGridWidth( uint width )
{
        if ( ( SONG_EDITOR_MIN_GRID_WIDTH <= width ) && ( SONG_EDITOR_MAX_GRID_WIDTH >= width ) ) {
                m_nGridWidth = width;
                resize( SongEditor::nMargin +
                                Preferences::get_instance()->getMaxBars() * m_nGridWidth, height() );
                invalidateBackground();
                update();
        }
}
 
QPoint SongEditor::xyToColumnRow( QPoint p )
{
        return QPoint( (p.x() - SongEditor::nMargin) / (int)m_nGridWidth, p.y() / (int)m_nGridHeight );
}
 
QPoint SongEditor::columnRowToXy( QPoint p )
{
        return QPoint( SongEditor::nMargin + p.x() * m_nGridWidth, p.y() * m_nGridHeight );
}
 
 
void SongEditor::togglePatternActive( int nColumn, int nRow ) {
        SE_togglePatternAction *action = new SE_togglePatternAction( nColumn, nRow );
        HydrogenApp::get_instance()->m_pUndoStack->push( action );
}
 
void SongEditor::setPatternActive( int nColumn, int nRow, bool bActivate )
{
        HydrogenApp* h2app = HydrogenApp::get_instance();
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        bool bPatternIsActive = pSong->isPatternActive( nColumn, nRow );
 
        if ( bPatternIsActive && ! bActivate || ! bPatternIsActive && bActivate ) {
                h2app->m_pUndoStack->push( new SE_togglePatternAction( nColumn, nRow ) );
        }
}
 
 
void SongEditor::selectAll() {
        PatternList *pPatternList = m_pHydrogen->getSong()->getPatternList();
        std::vector<PatternList*>* pColumns = m_pHydrogen->getSong()->getPatternGroupVector();
        m_selection.clearSelection();
        for ( int nRow = 0; nRow < pPatternList->size(); nRow++ ) {
                H2Core::Pattern *pPattern = pPatternList->get( nRow );
                for ( int nCol = 0; nCol < pColumns->size(); nCol++ ) {
                        PatternList *pColumn = ( *pColumns )[ nCol ];
                        for ( uint i = 0; i < pColumn->size(); i++) {
                                if ( pColumn->get(i) == pPattern ) { // esiste un pattern in questa posizione
                                        m_selection.addToSelection( QPoint( nCol, nRow ) );
                                }
                        }
                }
        }
        m_bSequenceChanged = true;
        update();
}
 
void SongEditor::selectNone() {
        m_selection.clearSelection();
 
        m_bSequenceChanged = true;
        update();
}
 
void SongEditor::deleteSelection() {
        QUndoStack *pUndo = HydrogenApp::get_instance()->m_pUndoStack;
        std::vector< QPoint > addCells, deleteCells, mergeCells;
        for ( QPoint cell : m_selection ) {
                deleteCells.push_back( cell );
        }
        pUndo->push( new SE_modifyPatternCellsAction( addCells, deleteCells, mergeCells,
                                                                                                  tr( "Delete selected cells" ) ) );
        m_selection.clearSelection();
}
 

void SongEditor::copy() {
        XMLDoc doc;
        XMLNode selection = doc.set_root( "patternSelection" );
        XMLNode cellList = selection.createNode( "cellList" );
        XMLNode positionNode = selection.createNode( "sourcePosition" );
        // Top left of selection
        int nMinX, nMinY;
        bool bWrotePattern = false;
 
        for ( QPoint cell : m_selection ) {
                XMLNode cellNode = cellList.createNode( "cell" );
                cellNode.write_int( "x", cell.x() );
                cellNode.write_int( "y", cell.y() );
                if ( bWrotePattern ) {
                        nMinX = std::min( nMinX, cell.x() );
                        nMinY = std::min( nMinY, cell.y() );
                } else {
                        nMinX = cell.x();
                        nMinY = cell.y();
                        bWrotePattern = true;
                }
        }
        if ( !bWrotePattern) {
                nMinX = m_nCursorColumn;
                nMinY = m_nCursorRow;
        }
        positionNode.write_int( "column", nMinX );
        positionNode.write_int( "row", nMinY );
 
        QApplication::clipboard()->setText( doc.toString() );
 
        // Show the keyboard cursor so the user knows where the insertion point will be
        HydrogenApp::get_instance()->setHideKeyboardCursor( false );
}
 
void SongEditor::paste() {
        QUndoStack *pUndo = HydrogenApp::get_instance()->m_pUndoStack;
        int nDeltaColumn = 0, nDeltaRow = 0;
        std::shared_ptr<Song> pSong = Hydrogen::get_instance()->getSong();
        int nPatterns = pSong->getPatternList()->size();
 
        XMLDoc doc;
        if ( ! doc.setContent( QApplication::clipboard()->text() ) ) {
                // Pasted something that's not valid XML.
                return;
        }
 
        m_selection.clearSelection();
        updateGridCells();
 
        XMLNode selection = doc.firstChildElement( "patternSelection" );
        if ( ! selection.isNull() ) {
                // Got pattern selection.
                std::vector< QPoint > addCells, deleteCells, mergeCells;
 
                XMLNode cellList = selection.firstChildElement( "cellList" );
                if ( cellList.isNull() ) {
                        return;
                }
 
                XMLNode positionNode = selection.firstChildElement( "sourcePosition" );
 
                // If position information is supplied in the selection, use
                // it to adjust the location relative to the current keyboard
                // input cursor.
                if ( !positionNode.isNull() ) {
 
                        nDeltaColumn = m_nCursorColumn - positionNode.read_int( "column", m_nCursorColumn );
                        nDeltaRow = m_nCursorRow - positionNode.read_int( "row", m_nCursorRow );
                }
 
                if ( cellList.hasChildNodes() ) {
                        for ( XMLNode cellNode = cellList.firstChildElement( "cell" );
                                  ! cellNode.isNull();
                                  cellNode = cellNode.nextSiblingElement() ) {
                                int nCol = cellNode.read_int( "x", m_nCursorColumn ) + nDeltaColumn;
                                int nRow = cellNode.read_int( "y", m_nCursorRow ) + nDeltaRow;
                                if ( nCol >= 0 && nRow >= 0 && nRow < nPatterns ) {
                                        // Paste cells
                                        QPoint p = QPoint( nCol, nRow );
                                        if ( m_gridCells.find( p ) == m_gridCells.end() ) {
                                                // Cell is not active. Activate it.
                                                addCells.push_back( p );
                                        } else {
                                                // Merge cell with existing
                                                mergeCells.push_back( p );
                                        }
                                }
                        }
 
                        pUndo->push( new SE_modifyPatternCellsAction( addCells, deleteCells, mergeCells,
                                                                                                                  tr( "Paste cells" ) ) );
                }
        }
}
 
void SongEditor::cut() {
        copy();
        deleteSelection();
}
 
void SongEditor::keyPressEvent( QKeyEvent * ev )
{
        auto pHydrogenApp = HydrogenApp::get_instance();
        auto pHydrogen = Hydrogen::get_instance();
        auto pSong = pHydrogen->getSong();
        const int nBlockSize = 5, nWordSize = 5;
        
        bool bIsSelectionKey = false;
        bool bUnhideCursor = true;
 
        bool bOldCursorHidden = pHydrogenApp->hideKeyboardCursor();
        
        H2Core::Song::ActionMode actionMode = pHydrogen->getActionMode();
                
        if ( actionMode == H2Core::Song::ActionMode::selectMode ) {
                bIsSelectionKey = m_selection.keyPressEvent( ev );
        }
 
        PatternList *pPatternList = pSong->getPatternList();
        const QPoint centre = QPoint( m_nGridWidth / 2, m_nGridHeight / 2 );
        bool bSelectionKey = false;
 
        int nMaxPatternSequence = Preferences::get_instance()->getMaxBars();
 
        updateModifiers( ev );
 
        if ( bIsSelectionKey ) {
                // Key was claimed by selection
        } else if ( ev->key() == Qt::Key_Delete ) {
                // Key: Delete: delete selected pattern cells, or cell at current position
                if ( m_selection.begin() != m_selection.end() ) {
                        deleteSelection();
                } else {
                        // No selection, delete at the current cursor position
                        setPatternActive( m_nCursorColumn, m_nCursorRow, false );
                }
 
        } else if ( ev->matches( QKeySequence::MoveToNextChar ) || ( bSelectionKey = ev->matches( QKeySequence::SelectNextChar ) ) ) {
                // ->
                if ( m_nCursorColumn < nMaxPatternSequence -1 ) {
                        m_nCursorColumn += 1;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToNextWord ) || ( bSelectionKey = ev->matches( QKeySequence::SelectNextWord ) ) ) {
                // -->
                m_nCursorColumn = std::min( (int)nMaxPatternSequence, m_nCursorColumn + nWordSize );
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfLine ) || ( bSelectionKey = ev->matches( QKeySequence::SelectEndOfLine ) ) ) {
                // ->|
                m_nCursorColumn = nMaxPatternSequence -1;
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousChar ) || ( bSelectionKey = ev->matches( QKeySequence::SelectPreviousChar ) ) ) {
                // <-
                if ( m_nCursorColumn > 0 ) {
                        m_nCursorColumn -= 1;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousWord ) || ( bSelectionKey = ev->matches( QKeySequence::SelectPreviousWord ) ) ) {
                // <--
                m_nCursorColumn = std::max( 0, m_nCursorColumn - nWordSize );
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfLine ) || ( bSelectionKey = ev->matches( QKeySequence::SelectStartOfLine ) ) ) {
                // |<-
                m_nCursorColumn = 0;
 
        } else if ( ev->matches( QKeySequence::MoveToNextLine ) || ( bSelectionKey = ev->matches( QKeySequence::SelectNextLine ) ) ) {
                if ( m_nCursorRow < pPatternList->size()-1 ) {
                        m_nCursorRow += 1;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfBlock ) || ( bSelectionKey = ev->matches( QKeySequence::SelectEndOfBlock ) ) ) {
                m_nCursorRow = std::min( pPatternList->size()-1, m_nCursorRow + nBlockSize );
 
        } else if ( ev->matches( QKeySequence::MoveToNextPage ) || ( bSelectionKey = ev->matches( QKeySequence::SelectNextPage ) ) ) {
                // Page down, scroll by the number of patterns that fit into the viewport
                QWidget *pParent = dynamic_cast< QWidget *>( parent() );
                assert( pParent );
                m_nCursorRow += pParent->height() / m_nGridHeight;
 
                if ( m_nCursorRow >= pPatternList->size() ) {
                        m_nCursorRow = pPatternList->size()-1;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToEndOfDocument ) || ( bSelectionKey = ev->matches( QKeySequence::SelectEndOfDocument ) ) ) {
                m_nCursorRow = pPatternList->size() -1;
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousLine ) || ( bSelectionKey = ev->matches( QKeySequence::SelectPreviousLine ) ) ) {
                if ( m_nCursorRow > 0 ) {
                        m_nCursorRow -= 1;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfBlock ) || ( bSelectionKey = ev->matches( QKeySequence::SelectStartOfBlock ) ) ) {
                m_nCursorRow = std::max( 0, m_nCursorRow - nBlockSize );
 
 
        } else if ( ev->matches( QKeySequence::MoveToPreviousPage ) || ( bSelectionKey = ev->matches( QKeySequence::SelectPreviousPage ) ) ) {
                QWidget *pParent = dynamic_cast< QWidget *>( parent() );
                assert( pParent );
                m_nCursorRow -= pParent->height() / m_nGridHeight;
 
                if ( m_nCursorRow < 0 ) {
                        m_nCursorRow = 0;
                }
 
        } else if ( ev->matches( QKeySequence::MoveToStartOfDocument ) || ( bSelectionKey = ev->matches( QKeySequence::SelectStartOfDocument ) ) ) {
                m_nCursorRow = 0;
 
        } else if ( ev->matches( QKeySequence::SelectAll ) ) {
                // Key: Ctrl + A: Select all pattern
                bSelectionKey = true;
                bUnhideCursor = false;
                if ( actionMode == H2Core::Song::ActionMode::selectMode ) {
                        selectAll();
                }
 
        } else if ( ev->matches( QKeySequence::Deselect ) ) {
                // Key: Shift + Ctrl + A: deselect any selected cells
                bSelectionKey = true;
                bUnhideCursor = false;
                if ( actionMode == H2Core::Song::ActionMode::selectMode ) {
                        selectNone();
                        m_bSequenceChanged = false;
                }
 
        } else if ( ev->matches( QKeySequence::Copy ) ) {
                bUnhideCursor = false;
                copy();
 
        } else if ( ev->matches( QKeySequence::Paste ) ) {
                bUnhideCursor = false;
                paste();
        } else if ( ev->matches( QKeySequence::Cut ) ) {
                bUnhideCursor = false;
                cut();
 
        } else if ( ev->key() == Qt::Key_Enter || ev->key() == Qt::Key_Return ) {
                // Key: Return: Set or clear cell (draw mode), or start/end selection or move (select mode)
 
                // In DRAW mode, Enter's obvious action is the same as a
                // click - insert or delete pattern.
                togglePatternActive( m_nCursorColumn, m_nCursorRow );
 
        } else {
                ev->ignore();
                pHydrogenApp->setHideKeyboardCursor( true );
 
                if ( bOldCursorHidden != pHydrogenApp->hideKeyboardCursor() ) {
                        pHydrogenApp->getSongEditorPanel()->getSongEditorPatternList()->update();
                        pHydrogenApp->getSongEditorPanel()->getSongEditorPositionRuler()->update();
                        update();
                }
                return;
        }
        if ( bUnhideCursor ) {
                pHydrogenApp->setHideKeyboardCursor( false );
        }
 
        if ( bSelectionKey ) {
                // If a "select" key movement is used in "draw" mode, it's probably a good idea to go straight into
                // "select" mode.
                if ( actionMode == H2Core::Song::ActionMode::drawMode ) {
                        pHydrogen->setActionMode( H2Core::Song::ActionMode::selectMode );
                }
                // Any selection key may need a repaint of the selection
                m_bSequenceChanged = true;
        }
        if ( m_selection.isMoving() ) {
                // If a selection is being moved, it will need to be repainted
                m_bSequenceChanged = true;
        }
 
        QPoint cursorCentre = columnRowToXy( QPoint( m_nCursorColumn, m_nCursorRow ) ) + centre;
        m_pScrollView->ensureVisible( cursorCentre.x(), cursorCentre.y() );
        m_selection.updateKeyboardCursorPosition( getKeyboardCursorRect() );
 
        if ( ! pHydrogenApp->hideKeyboardCursor() ) {
                pHydrogenApp->getSongEditorPanel()->getSongEditorPatternList()->update();
                pHydrogenApp->getSongEditorPanel()->getSongEditorPositionRuler()->update();
        }       
        update();
        ev->accept();
}
 
void SongEditor::keyReleaseEvent( QKeyEvent * ev ) {
        updateModifiers( ev );
}
 
// Make cursor visible on focus
void SongEditor::focusInEvent( QFocusEvent *ev )
{
        if ( ev->reason() == Qt::TabFocusReason || ev->reason() == Qt::BacktabFocusReason ) {
                QPoint pos = columnRowToXy( QPoint( m_nCursorColumn, m_nCursorRow ))
                        + QPoint( m_nGridWidth / 2, m_nGridHeight / 2 );
                m_pScrollView->ensureVisible( pos.x(), pos.y() );
                HydrogenApp::get_instance()->setHideKeyboardCursor( false );
        }
 
        // If there are some patterns selected, we have to switch their
        // border color inactive <-> active.
        invalidateBackground();
        update();
        
        if ( ! HydrogenApp::get_instance()->hideKeyboardCursor() ) {
                HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPatternList()->update();
                HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPositionRuler()->update();
        }
}
 
// Make cursor hidden
void SongEditor::focusOutEvent( QFocusEvent *ev )
{
        UNUSED( ev );
 
        // If there are some patterns selected, we have to switch their
        // border color inactive <-> active.
        invalidateBackground();
        update();
        
        if ( ! HydrogenApp::get_instance()->hideKeyboardCursor() ) {
                HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPatternList()->update();
                HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPositionRuler()->update();
        }
}
 
 
// Implement comparison between QPoints needed for std::set
int operator<( QPoint a, QPoint b ) {
        int nAx = a.x(), nBx = b.x();
        if ( nAx != nBx ) {
                return nAx < nBx;
        } else {
                int nAy = a.y(), nBy = b.y();
                return nAy < nBy;
        }
}
 
void SongEditor::mousePressEvent( QMouseEvent *ev )
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        auto pHydrogenApp = HydrogenApp::get_instance();
        updateModifiers( ev );
        m_currentMousePosition = pEv->position().toPoint();
        m_bSequenceChanged = true;
 
        // Update keyboard cursor position
        QPoint p = xyToColumnRow( pEv->position().toPoint() );
        m_nCursorColumn = p.x();
        m_nCursorRow = p.y();
 
        bool bOldCursorHidden = pHydrogenApp->hideKeyboardCursor();
        
        pHydrogenApp->setHideKeyboardCursor( true );
 
        if ( Hydrogen::get_instance()->getActionMode() == H2Core::Song::ActionMode::selectMode ) {
                m_selection.mousePressEvent( ev );
                if ( ! pHydrogenApp->hideKeyboardCursor() ) {
                        pHydrogenApp->getSongEditorPanel()->getSongEditorPatternList()->update();
                        pHydrogenApp->getSongEditorPanel()->getSongEditorPositionRuler()->update();
                        update();
                }
 
        } else {
                if ( ev->button() == Qt::LeftButton ) {
                        // Start of a drawing gesture. Pick up whether we are painting Active or Inactive cells.
                        QPoint p = xyToColumnRow( pEv->position().toPoint() );
                        m_bDrawingActiveCell = Hydrogen::get_instance()->getSong()->isPatternActive( p.x(), p.y() );
                        setPatternActive( p.x(), p.y(), ! m_bDrawingActiveCell );
                        m_pSongEditorPanel->updatePlaybackTrackIfNecessary();
 
                } else if ( ev->button() == Qt::RightButton ) {
                        m_pPopupMenu->popup( pEv->globalPosition().toPoint() );
                }
        }
 
        // Cursor just got hidden.
        if ( bOldCursorHidden != pHydrogenApp->hideKeyboardCursor() ) {
                pHydrogenApp->getSongEditorPanel()->getSongEditorPatternList()->update();
                pHydrogenApp->getSongEditorPanel()->getSongEditorPositionRuler()->update();
                update();
        }
}
 
 
void SongEditor::updateModifiers( QInputEvent *ev )
{
        if ( ev->modifiers() == Qt::ControlModifier ) {
                m_bCopyNotMove = true;
        } else {
                m_bCopyNotMove = false;
        }
 
        if ( QKeyEvent *pEv = dynamic_cast<QKeyEvent*>( ev ) ) {
                // Keyboard events for press and release of modifier keys don't have those keys in the modifiers set,
                // so explicitly update these.
                if ( pEv->key() == Qt::Key_Control ) {
                        m_bCopyNotMove = ( ev->type() == QEvent::KeyPress );
                }
        }
 
        if ( m_selection.isMouseGesture() && m_selection.isMoving() ) {
                // If a selection is currently being moved, change the cursor
                // appropriately. Selection will change it back after the move
                // is complete (or abandoned)
                if ( m_bCopyNotMove &&  cursor().shape() != Qt::DragCopyCursor ) {
                        setCursor( QCursor( Qt::DragCopyCursor ) );
                } else if ( !m_bCopyNotMove && cursor().shape() != Qt::DragMoveCursor ) {
                        setCursor( QCursor( Qt::DragMoveCursor ) );
                }
        }
 
}
 
void SongEditor::mouseMoveEvent(QMouseEvent *ev)
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        auto pHydrogenApp = HydrogenApp::get_instance();
        auto pSong = Hydrogen::get_instance()->getSong();
        updateModifiers( ev );
        m_currentMousePosition = pEv->position().toPoint();
        bool bOldCursorHidden = pHydrogenApp->hideKeyboardCursor();
 
        if ( Hydrogen::get_instance()->getActionMode() == H2Core::Song::ActionMode::selectMode ) {
                m_selection.mouseMoveEvent( ev );
        } else {
                if ( pEv->position().x() < SongEditor::nMargin ) {
                        return;
                }
 
                QPoint p = xyToColumnRow( pEv->position().toPoint() );
                if ( m_nCursorColumn == p.x() && m_nCursorRow == p.y() ) {
                        // Cursor has not entered a different cell yet.
                        return;
                }
                m_nCursorColumn = p.x();
                m_nCursorRow = p.y();
                HydrogenApp::get_instance()->setHideKeyboardCursor( true );
 
                if ( m_nCursorRow >= pSong->getPatternList()->size() ) {
                        // We are below the bottom of the pattern list.
                        return;
                }
 
                // Drawing mode: continue drawing over other cells
                setPatternActive( p.x(), p.y(), ! m_bDrawingActiveCell );
        }
 
        // Cursor just got hidden.
        if ( bOldCursorHidden != pHydrogenApp->hideKeyboardCursor() ) {
                pHydrogenApp->getSongEditorPanel()->getSongEditorPatternList()->update();
                pHydrogenApp->getSongEditorPanel()->getSongEditorPositionRuler()->update();
                update();
        }
}
 
void SongEditor::mouseDragStartEvent( QMouseEvent *ev )
{
}
 
void SongEditor::mouseDragUpdateEvent( QMouseEvent *ev )
{
}
 
void SongEditor::mouseDragEndEvent( QMouseEvent *ev )
{
        unsetCursor();
}
 
void SongEditor::selectionMoveEndEvent( QInputEvent *ev )
{
        HydrogenApp *pApp = HydrogenApp::get_instance();
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        int nMaxPattern = pPatternList->size();
 
        updateModifiers( ev );
        QPoint offset = movingGridOffset();
        if ( offset == QPoint( 0, 0 ) ) {
                return;
        }
        std::vector< QPoint > addCells, deleteCells, mergeCells;
 
        updateGridCells();
 
        for ( QPoint cell : m_selection ) {
                // Remove original active cell
                if ( ! m_bCopyNotMove ) {
                        deleteCells.push_back( cell );
                }
                QPoint newCell = cell + offset;
                // Place new cell if not already active
                if ( newCell.x() >= 0 && newCell.y() >= 0 && newCell.y() < nMaxPattern ) {
                        if ( m_gridCells.find( newCell ) == m_gridCells.end() || m_selection.isSelected( newCell ) ) {
                                addCells.push_back( newCell );
                        } else {
                                // Cell is moved, but merges with existing cell
                                mergeCells.push_back( newCell );
                        }
                }
        }
 
        pApp->m_pUndoStack->push( new SE_modifyPatternCellsAction( addCells, deleteCells, mergeCells,
                                                                                                                           (m_bCopyNotMove
                                                                                                                                ? tr( "Copy selected cells" )
                                                                                                                                : tr( "Move selected cells" ) ) ) );
}
 
 
void SongEditor::mouseClickEvent( QMouseEvent *ev )
{
        assert( m_pHydrogen->getActionMode() == H2Core::Song::ActionMode::selectMode );
 
        auto pEv = static_cast<MouseEvent*>( ev );
 
        if ( ev->button() == Qt::LeftButton ) {
                QPoint p = xyToColumnRow( pEv->position().toPoint() );
 
                m_selection.clearSelection();
                togglePatternActive( p.x(), p.y() );
                m_bSequenceChanged = true;
                update();
                if ( ! HydrogenApp::get_instance()->hideKeyboardCursor() ) {
                        HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPatternList()->update();
                        HydrogenApp::get_instance()->getSongEditorPanel()->getSongEditorPositionRuler()->update();
                }
 
        } else if ( ev->button() == Qt::RightButton ) {
                m_pPopupMenu->popup( pEv->globalPosition().toPoint() );
        }
}
 
void SongEditor::mouseReleaseEvent( QMouseEvent *ev )
{
        if ( m_pHydrogen->getActionMode() == H2Core::Song::ActionMode::selectMode ) {
                m_selection.mouseReleaseEvent( ev );
                return;
        }
}
 

void SongEditor::modifyPatternCellsAction( std::vector<QPoint> & addCells, std::vector<QPoint> & deleteCells, std::vector<QPoint> & selectCells ) {
        
        for ( QPoint cell : deleteCells ) {
                setPatternActive( cell.x(), cell.y(), false );
        }
 
        m_selection.clearSelection();
        for ( QPoint cell : addCells ) {
                setPatternActive( cell.x(), cell.y(), true );
                m_selection.addToSelection( cell );
        }
        // Select additional cells (probably merged cells on redo)
        for ( QPoint cell : selectCells ) {
                m_selection.addToSelection( cell );
        }
}
 
void SongEditor::updateWidget() {
        // Only update the drawn sequence if necessary. This is only possible when the c
        if ( m_selection.isMoving() ) {
                QPoint currentGridOffset = movingGridOffset();
                // Moving a selection never has to update the sequence (it's drawn on top of the sequence). Update
                // is only ever needed when the move delta (in grid spaces) changes
                if ( m_previousGridOffset != currentGridOffset ) {
                        update();
                        m_previousGridOffset = currentGridOffset;
                }
        } else if ( m_selection.isLasso() ) {
                bool bCellBoundaryCrossed = xyToColumnRow( m_previousMousePosition ) !=
                        xyToColumnRow( m_currentMousePosition );
                // Selection must redraw the pattern when a cell boundary is crossed, as the selected cells are
                // drawn when drawing the pattern.
                if ( bCellBoundaryCrossed ) {
                        m_bSequenceChanged = true;
                }
                update();
        } else {
                // Other reasons: force update
                m_bSequenceChanged = true;
                update();
        }
        m_previousMousePosition = m_currentMousePosition;
}
 
 
void SongEditor::updatePosition( float fTick ) {
        if ( fTick != m_fTick ) {
                float fDiff = static_cast<float>(m_nGridWidth) * (fTick - m_fTick);
                m_fTick = fTick;
                int nX = SongEditorPositionRuler::tickToColumn( m_fTick, m_nGridWidth );
                int nOffset = Skin::getPlayheadShaftOffset();
                QRect updateRect( nX + nOffset -2, 0, 4, height() );
                update( updateRect );
                if ( fDiff > 1.0 || fDiff < -1.0 ) {
                        // New cursor is far enough away from the old one that the single update rect won't cover both. So
                        // update at the old location as well.
                        updateRect.translate( -fDiff, 0 );
                        update( updateRect );
                }
        }
}
 
void SongEditor::patternModifiedEvent() {
        // This can change the length of one pattern in a column
        // containing multiple ones.
        invalidateBackground();
        update();
}
 
void SongEditor::relocationEvent() {
        if ( Hydrogen::get_instance()->isPatternEditorLocked() ) {
                invalidateBackground();
                update();
        }
}
 
void SongEditor::patternEditorLockedEvent() {
        if ( Hydrogen::get_instance()->isPatternEditorLocked() ) {
                invalidateBackground();
                update();
        }
}
 
void SongEditor::paintEvent( QPaintEvent *ev )
{
        if ( m_bBackgroundInvalid ) {
                createBackground();
        }
 
        // ridisegno tutto solo se sono cambiate le note
        if (m_bSequenceChanged) {
                m_bSequenceChanged = false;
                drawSequence();
        }
        
        auto pPref = Preferences::get_instance();
 
        QPainter painter(this);
        painter.drawPixmap( ev->rect(), *m_pSequencePixmap, ev->rect() );
 
        // Draw moving selected cells
        QColor patternColor( 0, 0, 0 );
        if ( m_selection.isMoving() ) {
                QPoint offset = movingGridOffset();
                for ( QPoint point : m_selection ) {
                        int nWidth = m_gridCells[ point ].m_fWidth * m_nGridWidth;
                        QRect r = QRect( columnRowToXy( point + offset ),
                                                         QSize( nWidth, m_nGridHeight ) )
                                .marginsRemoved( QMargins( 2, 4, 1 , 3 ) );
                        painter.fillRect( r, patternColor );
                }
        }
        // Draw playhead
        if ( m_fTick != -1 ) {
                int nX = SongEditorPositionRuler::tickToColumn( m_fTick, m_nGridWidth );
                int nOffset = Skin::getPlayheadShaftOffset();
                Skin::setPlayheadPen( &painter, false );
                painter.drawLine( nX + nOffset, 0, nX + nOffset, height() );
        }
 
        drawFocus( painter );
 
        m_selection.paintSelection( &painter );
 
        // Draw cursor
        if ( ! HydrogenApp::get_instance()->hideKeyboardCursor() && hasFocus() ) {
                QPen p( pPref->getColorTheme()->m_cursorColor );
                p.setWidth( 2 );
                painter.setPen( p );
                painter.setRenderHint( QPainter::Antialiasing );
                // Aim to leave a visible gap between the border of the
                // pattern cell, and the cursor line, for consistency and
                // visibility.
                painter.drawRoundedRect( QRect( QPoint(0, 1 ) + columnRowToXy( QPoint(m_nCursorColumn, m_nCursorRow ) ),
                                                                                QSize( m_nGridWidth+1, m_nGridHeight-1 ) ),
                                                                 4, 4 );
        }
}
 
void SongEditor::drawFocus( QPainter& painter ) {
 
        if ( ! m_bEntered && ! hasFocus() ) {
                return;
        }
        
        QColor color = H2Core::Preferences::get_instance()->getColorTheme()->m_highlightColor;
 
        // If the mouse is placed on the widget but the user hasn't
        // clicked it yet, the highlight will be done more transparent to
        // indicate that keyboard inputs are not accepted yet.
        if ( ! hasFocus() ) {
                color.setAlpha( 125 );
        }
 
        int nStartX = m_pScrollView->horizontalScrollBar()->value();
        int nEndX = std::min( nStartX + m_pScrollView->viewport()->size().width(), width() );
        int nStartY = m_pScrollView->verticalScrollBar()->value();
        int nEndY = std::min( static_cast<int>( m_nGridHeight ) * m_pHydrogen->getSong()->getPatternList()->size(),
                                                  nStartY + m_pScrollView->viewport()->size().height() );
 
        QPen pen( color );
        pen.setWidth( 4 );
        painter.setPen( pen );
        painter.drawLine( QPoint( nStartX, nStartY ), QPoint( nEndX, nStartY ) );
        painter.drawLine( QPoint( nStartX, nStartY ), QPoint( nStartX, nEndY ) );
        painter.drawLine( QPoint( nEndX, nStartY ), QPoint( nEndX, nEndY ) );
        painter.drawLine( QPoint( nEndX, nEndY ), QPoint( nStartX, nEndY ) );
}
 
void SongEditor::scrolled( int nValue ) {
        UNUSED( nValue );
        update();
}
 
#ifdef H2CORE_HAVE_QT6
void SongEditor::enterEvent( QEnterEvent *ev ) {
#else
void SongEditor::enterEvent( QEvent *ev ) {
#endif
        UNUSED( ev );
        m_bEntered = true;
        update();
}
 
void SongEditor::leaveEvent( QEvent *ev ) {
        UNUSED( ev );
        m_bEntered = false;
        update();
}
 
void SongEditor::createBackground()
{
        m_bBackgroundInvalid = false;
        auto pPref = H2Core::Preferences::get_instance();
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
 
        uint nPatterns = pSong->getPatternList()->size();
        int nSelectedPatternNumber = m_pHydrogen->getSelectedPatternNumber();
        int nMaxPatternSequence = pPref->getMaxBars();
 
        static int nOldHeight = -1;
        int nNewHeight = m_nGridHeight * nPatterns;
 
        if (nOldHeight != nNewHeight) {
                // cambiamento di dimensioni...
                if ( nNewHeight < m_nMinimumHeight ) {
                        WARNINGLOG( QString( "nNewHeight [%1] below minimum one [%2]" )
                                                .arg( nNewHeight ).arg( m_nMinimumHeight ) );
                        nNewHeight = m_nMinimumHeight;  // the pixmap should not be empty
                }
                if ( m_pBackgroundPixmap ) {
                        delete m_pBackgroundPixmap;
                }
                if ( m_pSequencePixmap ) {
                        delete m_pSequencePixmap;
                }
                m_pBackgroundPixmap = new QPixmap( width(), nNewHeight );    // initialize the pixmap
                m_pSequencePixmap = new QPixmap( width(), nNewHeight );        // initialize the pixmap
                this->resize( QSize( width(), nNewHeight ) );
        }
 
        
        m_pBackgroundPixmap->fill( pPref->getColorTheme()->m_songEditor_backgroundColor );
 
        QPainter p( m_pBackgroundPixmap );
        
        for ( int ii = 0; ii < nPatterns + 1; ii++) {
                if ( ( ii % 2 ) == 0 &&
                         ii != nSelectedPatternNumber ) {
                        continue;
                }
                
                int y = m_nGridHeight * ii;
                
                if ( ii == nSelectedPatternNumber ) {
                        p.fillRect( 0, y, nMaxPatternSequence * m_nGridWidth, m_nGridHeight,
                                                pPref->getColorTheme()->m_songEditor_selectedRowColor );
                } else {
                        p.fillRect( 0, y, nMaxPatternSequence * m_nGridWidth, m_nGridHeight,
                                                pPref->getColorTheme()->m_songEditor_alternateRowColor );
                }
        }
 
        p.setPen( QPen( pPref->getColorTheme()->m_songEditor_lineColor, 1,
                                        Qt::DotLine ) );
 
        // vertical lines
        for ( float ii = 0; ii <= nMaxPatternSequence + 1; ii++) {
                float x = SongEditor::nMargin + ii * m_nGridWidth;
                p.drawLine( x, 0, x, m_nGridHeight * nPatterns );
        }
        
        // horizontal lines
        for (uint i = 0; i < nPatterns; i++) {
                uint y = m_nGridHeight * i;
 
                p.drawLine( 0, y, (nMaxPatternSequence * m_nGridWidth), y );
        }
 
        // ~ celle
        m_bSequenceChanged = true;
 
}
 
void SongEditor::invalidateBackground() {
        m_bBackgroundInvalid = true;
}
 
// Update the GridCell representation.
void SongEditor::updateGridCells() {
 
        m_gridCells.clear();
        std::shared_ptr<Song> pSong = Hydrogen::get_instance()->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        std::vector< PatternList* > *pColumns = pSong->getPatternGroupVector();
 
        for ( int nColumn = 0; nColumn < pColumns->size(); nColumn++ ) {
                PatternList *pColumn = (*pColumns)[nColumn];
                int nMaxLength = pColumn->longest_pattern_length();
 
                for ( uint nPat = 0; nPat < pColumn->size(); nPat++ ) {
                        Pattern *pPattern = (*pColumn)[ nPat ];
                        int y = pPatternList->index( pPattern );
                        assert( y != -1 );
                        GridCell *pCell = &( m_gridCells[ QPoint( nColumn, y ) ] );
                        pCell->m_bActive = true;
                        pCell->m_fWidth = (float) pPattern->get_length() / nMaxLength;
 
                        for ( Pattern *pVPattern : *( pPattern->get_flattened_virtual_patterns() ) ) {
                                GridCell *pVCell = &( m_gridCells[ QPoint( nColumn, pPatternList->index( pVPattern ) ) ] );
                                pVCell->m_bDrawnVirtual = true;
                                pVCell->m_fWidth = (float) pVPattern->get_length() / nMaxLength;
                        }
                }
        }
}
 
// Return grid offset (in cell coordinate space) of moving selection
QPoint SongEditor::movingGridOffset( ) const {
        QPoint rawOffset = m_selection.movingOffset();
        // Quantize offset to multiples of m_nGrid{Width,Height}
        int x_bias = m_nGridWidth / 2, y_bias = m_nGridHeight / 2;
        if ( rawOffset.y() < 0 ) {
                y_bias = -y_bias;
        }
        if ( rawOffset.x() < 0 ) {
                x_bias = -x_bias;
        }
        int x_off = (rawOffset.x() + x_bias) / (int)m_nGridWidth;
        int y_off = (rawOffset.y() + y_bias) / (int)m_nGridHeight;
        return QPoint( x_off, y_off );
}
 
 
void SongEditor::drawSequence()
{
        QPainter p;
 
        p.begin( m_pSequencePixmap );
        p.drawPixmap( rect(), *m_pBackgroundPixmap, rect() );
        p.end();
 
        updateGridCells();
 
        // Draw using GridCells representation
        for ( auto it : m_gridCells ) {
                if ( ! m_selection.isSelected( QPoint( it.first.x(), it.first.y() ) ) ) {
                        drawPattern( it.first.x(), it.first.y(),
                                                 it.second.m_bDrawnVirtual, it.second.m_fWidth );
                }
        }
        // We draw all selected patterns in a second run to ensure their
        // border does have the proper color (else the bottom and left one
        // could be overwritten by an adjecent, unselected pattern).
        for ( auto it : m_gridCells ) {
                if ( m_selection.isSelected( QPoint( it.first.x(), it.first.y() ) ) ) {
                        drawPattern( it.first.x(), it.first.y(),
                                                 it.second.m_bDrawnVirtual, it.second.m_fWidth );
                }
        }
}
 
 
 
void SongEditor::drawPattern( int nPos, int nNumber, bool bInvertColour, double fWidth )
{
        QPainter p( m_pSequencePixmap );
        /*
         * The default color of the cubes in rgb is 97,167,251.
         */
        auto pPref = H2Core::Preferences::get_instance();
        std::shared_ptr<Song> pSong = Hydrogen::get_instance()->getSong();
        PatternList *pPatternList = pSong->getPatternList();
 
        QColor patternColor;
        /*
         * The following color modes are available:
         *
         * Automatic: Steps = Number of pattern in song and colors will be
         *            chosen internally.
         * Custom: Number of steps as well as the colors used are defined
         *            by the user.
         */
        if ( pPref->getColoringMethod() == H2Core::InterfaceTheme::ColoringMethod::Automatic ) {
                int nSteps = pPatternList->size();
 
                if( nSteps == 0 ) {
                        //beware of the division by zero..
                        nSteps = 1;
                }
 
                int nHue = ( (nNumber % nSteps) * (300 / nSteps) + 213) % 300;
                patternColor.setHsv( nHue , 156 , 249);
        } else {
                int nIndex = nNumber % pPref->getVisiblePatternColors();
                if ( nIndex > m_nMaxPatternColors ) {
                        nIndex = m_nMaxPatternColors;
                }
                patternColor = pPref->getPatternColors()[ nIndex ].toHsv();
        }
 
        if ( true == bInvertColour ) {
                patternColor = patternColor.darker(200);
        }
 
        bool bIsSelected = m_selection.isSelected( QPoint( nPos, nNumber ) );
 
        if ( bIsSelected ) {
                patternColor = patternColor.darker( 130 );
        }
 
        patternColor.setAlpha( 230 );
 
        int x = SongEditor::nMargin + m_nGridWidth * nPos;
        int y = m_nGridHeight * nNumber;
 
        p.fillRect( x + 1, y + 1, fWidth * (m_nGridWidth - 1), m_nGridHeight - 1, patternColor );
 
        // To better distinguish between the individual patterns, they
        // will have a pronounced border.
        QColor borderColor;
        if ( bIsSelected ){
                if ( hasFocus() ) {
                        borderColor = pPref->getColorTheme()->m_selectionHighlightColor;
                } else {
                        borderColor = pPref->getColorTheme()->m_selectionInactiveColor;
                }
        } else {
                borderColor = QColor( 0, 0, 0 );
        }
        p.setPen( borderColor );
        p.drawRect( x, y, fWidth * m_nGridWidth, m_nGridHeight );
}
 
std::vector<SongEditor::SelectionIndex> SongEditor::elementsIntersecting( QRect r )
{
        std::vector<SelectionIndex> elems;
        for ( auto it : m_gridCells ) {
                if ( r.intersects( QRect( columnRowToXy( it.first ),
                                                                  QSize( m_nGridWidth, m_nGridHeight) ) ) ) {
                        if ( ! it.second.m_bDrawnVirtual ) {
                                elems.push_back( it.first );
                        }
                }
        }
        return elems;
}
 
QRect SongEditor::getKeyboardCursorRect() {
        return QRect( QPoint( 0, 1 ) + columnRowToXy( QPoint( m_nCursorColumn, m_nCursorRow ) ),
                                  QSize( m_nGridWidth, m_nGridHeight -1 ) );
}
 
void SongEditor::clearThePatternSequenceVector( QString filename )
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
 
        m_pAudioEngine->lock( RIGHT_HERE );
 
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
 
        //before deleting the sequence, write a temp sequence file to disk
        pSong->writeTempPatternList( filename );
 
        std::vector<PatternList*> *pPatternGroupsVect = pSong->getPatternGroupVector();
        for (uint i = 0; i < pPatternGroupsVect->size(); i++) {
                PatternList *pPatternList = (*pPatternGroupsVect)[i];
                pPatternList->clear();
                delete pPatternList;
        }
        pPatternGroupsVect->clear();
        pHydrogen->updateSongSize();
        
        m_pAudioEngine->unlock();
 
        pHydrogen->setIsModified( true );
        m_bSequenceChanged = true;
        update();
}
 
void SongEditor::updateEditorandSetTrue()
{
        m_bSequenceChanged = true;
        update();
}
 
void SongEditor::onPreferencesChanged( H2Core::Preferences::Changes changes ) 
{
        if ( changes & ( H2Core::Preferences::Changes::GeneralTab |
                                         H2Core::Preferences::Changes::Colors |
                                         H2Core::Preferences::Changes::AppearanceTab ) ) {
                resize( SongEditor::nMargin +
                                Preferences::get_instance()->getMaxBars() * m_nGridWidth, height() );
 
                m_bSequenceChanged = true;
 
                // Required to be called at least once in order to make the
                // scroll bars match the (potential) new width.
                HydrogenApp::get_instance()->getSongEditorPanel()->updateAll();
        }
}
 
// :::::::::::::::::::
 
 
SongEditorPatternList::SongEditorPatternList( QWidget *parent )
 : QWidget( parent )
 , EventListener()
 , WidgetWithHighlightedList()
 , m_pBackgroundPixmap( nullptr )
 , m_nRowHovered( -1 )
{
        m_pHydrogen = Hydrogen::get_instance();
        m_pAudioEngine = m_pHydrogen->getAudioEngine();
 
        auto pPref = Preferences::get_instance();
        
        m_nWidth = 200;
        m_nGridHeight = pPref->getSongEditorGridHeight();
        setAttribute(Qt::WA_OpaquePaintEvent);
 
        setAcceptDrops(true);
        setMouseTracking( true );
 
        m_pPatternBeingEdited = nullptr;
 
        m_pLineEdit = new QLineEdit( "Inline Pattern Name", this );
        m_pLineEdit->setFrame( false );
        m_pLineEdit->hide();
        m_pLineEdit->setAcceptDrops( false );
        connect( m_pLineEdit, SIGNAL(editingFinished()), this, SLOT(inlineEditingFinished()) );
        connect( m_pLineEdit, SIGNAL(returnPressed()), this, SLOT(inlineEditingEntered()) );
 
        this->resize( m_nWidth, m_nInitialHeight );
 
        m_playingPattern_on_Pixmap.load( Skin::getImagePath() + "/songEditor/playingPattern_on.png" );
        m_playingPattern_off_Pixmap.load( Skin::getImagePath() + "/songEditor/playingPattern_off.png" );
        m_playingPattern_empty_Pixmap.load( Skin::getImagePath() + "/songEditor/playingPattern_empty.png" );
 
        m_pPatternPopup = new QMenu( this );
        m_pPatternPopup->addAction( tr("Duplicate"),  this, SLOT( patternPopup_duplicate() ) );
        m_pPatternPopup->addAction( tr("Delete"),  this, SLOT( patternPopup_delete() ) );
        m_pPatternPopup->addAction( tr("Fill/Clear..."),  this, SLOT( patternPopup_fill() ) );
        m_pPatternPopup->addAction( tr("Properties"),  this, SLOT( patternPopup_properties() ) );
        m_pPatternPopup->addAction( tr("Load Pattern"),  this, SLOT( patternPopup_load() ) );
        m_pPatternPopup->addAction( tr("Save Pattern"),  this, SLOT( patternPopup_save() ) );
        m_pPatternPopup->addAction( tr("Export Pattern"),  this, SLOT( patternPopup_export() ) );
        m_pPatternPopup->addAction( tr("Virtual Pattern"), this, SLOT( patternPopup_virtualPattern() ) );
        m_pPatternPopup->setObjectName( "PatternListPopup" );
 
        // Reset the clicked row once the popup is closed by clicking at
        // any position other than at an action of the popup.
        connect( m_pPatternPopup, &QMenu::aboutToHide, [=](){
                if ( m_rowSelection == RowSelection::Popup ) {
                        setRowSelection( RowSelection::None );
                }
        });
 
        HydrogenApp::get_instance()->addEventListener( this );
 
        QScrollArea *pScrollArea = dynamic_cast< QScrollArea * >( parentWidget()->parentWidget() );
        assert( pScrollArea );
        m_pDragScroller = new DragScroller( pScrollArea );
        
        m_pHighlightLockedTimer = new QTimer( this );
        m_pHighlightLockedTimer->setSingleShot( true );
        connect(m_pHighlightLockedTimer, &QTimer::timeout,
                        [=](){ HydrogenApp::get_instance()->getSongEditorPanel()->highlightPatternEditorLocked( false ); } );
 
        qreal pixelRatio = devicePixelRatio();
        m_pBackgroundPixmap = new QPixmap( m_nWidth * pixelRatio,
                                                                           height() * pixelRatio );
        m_pBackgroundPixmap->setDevicePixelRatio( pixelRatio );
        
        createBackground();
        update();
}
 
 
 
SongEditorPatternList::~SongEditorPatternList()
{
        if ( m_pBackgroundPixmap ) {
                delete m_pBackgroundPixmap;
        }
        delete m_pDragScroller;
}
 
 
void SongEditorPatternList::playingPatternsChangedEvent() {
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::setRowSelection( RowSelection rowSelection ) {
        m_rowSelection = rowSelection;
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::patternModifiedEvent() {
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::selectedPatternChangedEvent() {
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::nextPatternsChangedEvent() {
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::relocationEvent() {
        if ( Hydrogen::get_instance()->isPatternEditorLocked() ) {
                invalidateBackground();
                update();
        }
}
 
void SongEditorPatternList::patternEditorLockedEvent() {
        if ( Hydrogen::get_instance()->isPatternEditorLocked() ) {
                invalidateBackground();
                update();
        }
}

void SongEditorPatternList::mousePressEvent( QMouseEvent *ev )
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        __drag_start_position = pEv->position().toPoint();
        
        // -1 to compensate for the 1 pixel offset to align shadows and
        // -grid lines.
        int nRow = (( pEv->position().y() - 1 ) / m_nGridHeight);
 
        auto pSong = m_pHydrogen->getSong();
        if ( pSong == nullptr ) {
                return;
        }
        
        auto pPatternList = pSong->getPatternList();
 
        if ( nRow < 0 || nRow >= (int)pPatternList->size() ) {
                ERRORLOG( QString( "Row [%1] out of bound" ).arg( nRow ) );
                return;
        }
 
        if ( ( ev->button() == Qt::MiddleButton ||
                   ( ev->modifiers() == Qt::ControlModifier && ev->button() == Qt::RightButton ) ||
                   ( ev->modifiers() == Qt::ControlModifier && ev->button() == Qt::LeftButton ) ||
                   pEv->position().x() < 15 ) &&
                 m_pHydrogen->getPatternMode() == Song::PatternMode::Stacked ) {
                
                m_pHydrogen->toggleNextPattern( nRow );
        }
        else {
                if ( ! ( m_pHydrogen->isPatternEditorLocked() &&
                                 m_pHydrogen->getAudioEngine()->getState() ==
                                 AudioEngine::State::Playing ) ) {
                        m_pHydrogen->setSelectedPatternNumber( nRow );
                } else {
                        // Notify the users why nothing just happened by
                        // highlighting the pattern locked button in the
                        // SongEditorPanel.
                        HydrogenApp::get_instance()->getSongEditorPanel()->highlightPatternEditorLocked( true );
                        m_pHighlightLockedTimer->start( 250 );
                }
                
                if (ev->button() == Qt::RightButton)  {
 
                        if ( m_rowSelection == RowSelection::Dialog ) {
                                // There is still a dialog window opened from the last
                                // time. It needs to be closed before the popup will
                                // be shown again.
                                ERRORLOG( "A dialog is still opened. It needs to be closed first." );
                                return;
                        }
                        
                        m_nRowClicked = nRow;
                        setRowSelection( RowSelection::Popup );
                        m_pPatternPopup->popup( pEv->globalPosition().toPoint() );
                }
        }
 
        invalidateBackground();
        update();
}
 

void SongEditorPatternList::togglePattern( int row ) {
 
        m_pHydrogen->toggleNextPattern( row );
        invalidateBackground();
        update();
}
 
 
void SongEditorPatternList::mouseDoubleClickEvent( QMouseEvent *ev )
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        int row = (pEv->position().y() / m_nGridHeight);
        inlineEditPatternName( row );
}
 
void SongEditorPatternList::inlineEditPatternName( int row )
{
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
 
        if ( row >= (int)pPatternList->size() ) {
                return;
        }
        m_pPatternBeingEdited = pPatternList->get( row );
        m_pLineEdit->setGeometry( 23, row * m_nGridHeight + 1 , m_nWidth - 23, m_nGridHeight  );
        m_pLineEdit->setText( m_pPatternBeingEdited->get_name() );
        m_pLineEdit->selectAll();
        m_pLineEdit->show();
        m_pLineEdit->setFocus();
}
 
void SongEditorPatternList::inlineEditingEntered()
{
        assert( m_pPatternBeingEdited != nullptr );
        
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        
        /*
         * Make sure that the entered pattern name is unique.
         * If it is not, use an unused pattern name.
         */
        
        QString patternName = pPatternList->find_unused_pattern_name( m_pLineEdit->text(), m_pPatternBeingEdited );
 
        SE_modifyPatternPropertiesAction *action =
                new SE_modifyPatternPropertiesAction( m_pPatternBeingEdited->get_name(),
                                                                                          m_pPatternBeingEdited->get_info(),
                                                                                          m_pPatternBeingEdited->get_category(),
                                                                                          patternName,
                                                                                          m_pPatternBeingEdited->get_info(),
                                                                                          m_pPatternBeingEdited->get_category(),
                                                                                          pPatternList->index( m_pPatternBeingEdited ) );
        HydrogenApp::get_instance()->m_pUndoStack->push( action );
}
 
 
void SongEditorPatternList::inlineEditingFinished()
{
        m_pPatternBeingEdited = nullptr;
        m_pLineEdit->hide();
}
 
 
void SongEditorPatternList::paintEvent( QPaintEvent *ev )
{
        auto pPref = Preferences::get_instance();
        auto pHydrogenApp = HydrogenApp::get_instance();
        auto pSongEditor = pHydrogenApp->getSongEditorPanel()->getSongEditor();
        
        QPainter painter(this);
        qreal pixelRatio = devicePixelRatio();
        if ( width() != m_pBackgroundPixmap->width() ||
                 height() != m_pBackgroundPixmap->height() ||
                 pixelRatio != m_pBackgroundPixmap->devicePixelRatio() ||
                 m_bBackgroundInvalid ) {
                createBackground();
        }
        QRectF srcRect(
                        pixelRatio * ev->rect().x(),
                        pixelRatio * ev->rect().y(),
                        pixelRatio * ev->rect().width(),
                        pixelRatio * ev->rect().height()
        );
        painter.drawPixmap( ev->rect(), *m_pBackgroundPixmap, srcRect );
 
        // In case a row was right-clicked or the cursor is positioned on
        // a grid cell within this row, highlight it using a border.
        if ( ( ! pHydrogenApp->hideKeyboardCursor() &&
                   pSongEditor->hasFocus() ) ||
                 m_rowSelection != RowSelection::None ) {
                QColor colorHighlight = pPref->getColorTheme()->m_highlightColor;
                QPen pen;
 
                int nStartY;
                if ( m_rowSelection != RowSelection::None ) {
                        // In case a row was right-clicked, highlight it using a border.
                        pen.setColor( pPref->getColorTheme()->m_highlightColor);
                        nStartY = m_nRowClicked * m_nGridHeight;
                } else {
                        pen.setColor( pPref->getColorTheme()->m_cursorColor );
                        nStartY = pSongEditor->getCursorRow() * m_nGridHeight;
                }
                pen.setWidth( 2 );
                painter.setRenderHint( QPainter::Antialiasing );
                        
                painter.setPen( pen );
                painter.drawRoundedRect( QRect( 1, nStartY + 1, m_nWidth - 2,
                                                                                m_nGridHeight - 1 ), 4, 4 );
        }
}
 
 
void SongEditorPatternList::updateEditor()
{
        if(!isVisible()) {
                return;
        }
 
        update();
}
 
void SongEditorPatternList::songModeActivationEvent() {
 
        // Refresh pattern list display if in stacked mode
        if ( Hydrogen::get_instance()->getPatternMode() ==
                 Song::PatternMode::Stacked ) {
                invalidateBackground();
                update();
        }
}
 
void SongEditorPatternList::invalidateBackground()
{
        m_bBackgroundInvalid = true;
}
 
void SongEditorPatternList::createBackground()
{
        auto pPref = H2Core::Preferences::get_instance();
        m_bBackgroundInvalid = false;
 
        QFont boldTextFont( pPref->getLevel2FontFamily(), getPointSize( pPref->getFontSize() ) );
        boldTextFont.setBold( true );
 
        //Do not redraw anything if Export is active.
        //https://github.com/hydrogen-music/hydrogen/issues/857 
        if( m_pHydrogen->getIsExportSessionActive() ) {
                return;
        }
        
        const std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        if ( pSong == nullptr ) {
                ERRORLOG( "no song set" );
                return;
        }
 
        const auto pPatternList = pSong->getPatternList();
        int nPatterns = pPatternList->size();
        int nSelectedPattern = m_pHydrogen->getSelectedPatternNumber();
 
        int newHeight = m_nGridHeight * nPatterns + 1;
 
        if ( m_nWidth != m_pBackgroundPixmap->width() ||
                 newHeight != m_pBackgroundPixmap->height() ||
                 m_pBackgroundPixmap->devicePixelRatio() != devicePixelRatio() ) {
                if (newHeight == 0) {
                        newHeight = 1;  // the pixmap should not be empty
                }
                delete m_pBackgroundPixmap;
                qreal pixelRatio = devicePixelRatio();
                m_pBackgroundPixmap = new QPixmap( m_nWidth  * pixelRatio , newHeight * pixelRatio );        // initialize the pixmap
                m_pBackgroundPixmap->setDevicePixelRatio( pixelRatio );
                this->resize( m_nWidth, newHeight );
        }
 
        QColor backgroundColor = pPref->getColorTheme()->m_songEditor_backgroundColor.darker( 120 );
        QColor backgroundColorSelected = pPref->getColorTheme()->m_songEditor_selectedRowColor.darker( 114 );
        QColor backgroundColorAlternate =
                pPref->getColorTheme()->m_songEditor_alternateRowColor.darker( 132 );
        QColor backgroundColorVirtual =
                pPref->getColorTheme()->m_songEditor_virtualRowColor;
 
        QPainter p( m_pBackgroundPixmap );
 
 
        // Offset the pattern list by one pixel to align the dark shadows
        // at the bottom of each row with the grid lines in the song editor.
        p.fillRect( QRect( 0, 0, width(), 1 ), pPref->getColorTheme()->m_windowColor );
        
        p.setFont( boldTextFont );
        for ( int ii = 0; ii < nPatterns; ii++ ) {
                uint y = m_nGridHeight * ii + 1;
                
                if ( ii == nSelectedPattern ) {
                        Skin::drawListBackground( &p, QRect( 0, y, width(), m_nGridHeight ),
                                                                          backgroundColorSelected, false );
                } else {
                        const auto pPattern = pPatternList->get( ii );
                        if ( pPattern != nullptr && pPattern->isVirtual() ) {
                                Skin::drawListBackground( &p, QRect( 0, y, width(), m_nGridHeight ),
                                                                                  backgroundColorVirtual,
                                                                                  ii == m_nRowHovered );
                        }
                        else if ( ( ii % 2 ) == 0 ) {
                                Skin::drawListBackground( &p, QRect( 0, y, width(), m_nGridHeight ),
                                                                                  backgroundColor,
                                                                                  ii == m_nRowHovered );
                        }
                        else {
                                Skin::drawListBackground( &p, QRect( 0, y, width(), m_nGridHeight ),
                                                                                  backgroundColorAlternate,
                                                                                  ii == m_nRowHovered );
                        }
                }
        }
 
        std::unique_ptr<PatternDisplayInfo[]> PatternArray{new PatternDisplayInfo[nPatterns]};
 
        m_pAudioEngine->lock( RIGHT_HERE );
        auto pPlayingPatterns = m_pAudioEngine->getPlayingPatterns();
 
        //assemble the data..
        for ( int i = 0; i < nPatterns; i++ ) {
                H2Core::Pattern *pPattern = pSong->getPatternList()->get(i);
                if ( pPattern == nullptr ) {
                        continue;
                }
 
                if ( pPlayingPatterns->index( pPattern ) != -1 ) {
                        PatternArray[i].bActive = true;
                } else {
                        PatternArray[i].bActive = false;
                }
 
                if ( m_pAudioEngine->getNextPatterns()->index( pPattern ) != -1 ) {
                        PatternArray[i].bNext = true;
                } else {
                        PatternArray[i].bNext = false;
                }
 
                PatternArray[i].sPatternName = pPattern->get_name();
        }
        m_pAudioEngine->unlock();

        for ( int i = 0; i < nPatterns; i++ ) {
                if ( i == nSelectedPattern ) {
                        p.setPen( pPref->getColorTheme()->m_songEditor_selectedRowTextColor );
                }
                else {
                        p.setPen( pPref->getColorTheme()->m_songEditor_textColor );
                }
 
                uint text_y = i * m_nGridHeight;
 
                p.drawText( 25, text_y - 1, m_nWidth - 25, m_nGridHeight + 2,
                                        Qt::AlignVCenter, PatternArray[i].sPatternName);
 
                Skin::Stacked mode = Skin::Stacked::None;
                if ( PatternArray[i].bNext && PatternArray[i].bActive) {
                        mode = Skin::Stacked::OffNext;
                }
                else if ( PatternArray[i].bNext ) {
                        mode = Skin::Stacked::OnNext;
                }
                else if (PatternArray[i].bActive) {
                        mode = Skin::Stacked::On;
                }
                else if ( m_pHydrogen->getPatternMode() == Song::PatternMode::Stacked ) {
                        mode = Skin::Stacked::Off;
                }
                
                if ( mode != Skin::Stacked::None ) {
                        Skin::drawStackedIndicator( &p, 5, text_y + 4, mode );
                }
 
        }
}
 
void SongEditorPatternList::stackedModeActivationEvent( int ) {
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::patternPopup_virtualPattern()
{
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        if ( pSong == nullptr ) {
                ERRORLOG( "no song" );
                return;
        }
        PatternList *pPatternList = pSong->getPatternList();
        if ( pPatternList == nullptr ) {
                ERRORLOG( "no pattern list");
                return;
        }
 
        setRowSelection( RowSelection::Dialog );
        
        VirtualPatternDialog* pDialog = new VirtualPatternDialog( this );
        QListWidget* pPatternListWidget = pDialog->patternList;
        pPatternListWidget->setSortingEnabled(1);
        
        auto pPatternClicked = pPatternList->get( m_nRowClicked );
 
        std::map<QString, Pattern*> patternNameMap;
 
        for ( const auto& pPattern : *pPatternList ) {
                QString sPatternName = pPattern->get_name();
 
                if ( sPatternName == pPatternClicked->get_name() ) {
                        // Current pattern. A virtual pattern must not contain itself.
                        continue;
                }
 
                patternNameMap[ sPatternName ] = pPattern;
 
                QListWidgetItem* pNewItem =
                        new QListWidgetItem( sPatternName, pPatternListWidget);
                pPatternListWidget->insertItem( 0, pNewItem );
 
                if ( pPatternClicked->get_virtual_patterns()->find( pPattern ) !=
                         pPatternClicked->get_virtual_patterns()->end() ) {
                        // pattern is already contained in virtual pattern.
                        pNewItem->setSelected( true );
                }
        }
 
        if ( pDialog->exec() == QDialog::Accepted ) {
                pPatternClicked->virtual_patterns_clear();
                for ( int ii = 0; ii < pPatternListWidget->count(); ++ii ) {
                        QListWidgetItem* pListItem = pPatternListWidget->item( ii );
                        if ( pListItem != nullptr && pListItem->isSelected() ) {
                                if ( patternNameMap.find( pListItem->text() ) !=
                                         patternNameMap.end() ) {
                                        pPatternClicked->virtual_patterns_add(
                                                patternNameMap[ pListItem->text() ] );
                                }
                                else {
                                        ERRORLOG( QString( "Selected pattern [%1] could not be retrieved" )
                                                          .arg( pListItem->text() ) );
                                }
                        }
                }
                
                m_pHydrogen->updateVirtualPatterns();
        }
        
        delete pDialog;
 
        setRowSelection( RowSelection::None );
}//patternPopup_virtualPattern
 
 
 
void SongEditorPatternList::patternPopup_load()
{
        setRowSelection( RowSelection::Dialog );
        
        auto pHydrogen = Hydrogen::get_instance();
        auto pSong = pHydrogen->getSong();
 
        if ( pSong == nullptr ) {
                setRowSelection( RowSelection::None );
                return;
        }
        
        Pattern* pPattern = pSong->getPatternList()->get( m_nRowClicked );
 
        QString sPath = Preferences::get_instance()->getLastOpenPatternDirectory();
        if ( ! Filesystem::dir_readable( sPath, false ) ){
                sPath = Filesystem::patterns_dir();
        }
 
        FileDialog fd(this);
        fd.setAcceptMode( QFileDialog::AcceptOpen );
        fd.setFileMode( QFileDialog::ExistingFile );
        fd.setNameFilter( Filesystem::patterns_filter_name );
        fd.setDirectory( sPath );
        fd.setWindowTitle( QString( tr( "Open Pattern to Replace " )
                                                                .append( pPattern->get_name() ) ) );
 
        if (fd.exec() != QDialog::Accepted) {
                setRowSelection( RowSelection::None );
                return;
        }
        QString patternPath = fd.selectedFiles().first();
 
        QString prevPatternPath =
                Files::savePatternTmp( pPattern->get_name(), pPattern, pSong,
                                                           pHydrogen->getLastLoadedDrumkitName() );
        if ( prevPatternPath.isEmpty() ) {
                QMessageBox::warning( this, "Hydrogen", tr("Could not save pattern to temporary directory.") );
                setRowSelection( RowSelection::None );
                return;
        }
        QString sequencePath = Filesystem::tmp_file_path( "SEQ.xml" );
        if ( !pSong->writeTempPatternList( sequencePath ) ) {
                QMessageBox::warning( this, "Hydrogen", tr("Could not export sequence.") );
                setRowSelection( RowSelection::None );
                return;
        }
        Preferences::get_instance()->setLastOpenPatternDirectory( fd.directory().absolutePath() );
 
        SE_loadPatternAction *action =
                new SE_loadPatternAction( patternPath, prevPatternPath, sequencePath,
                                                                  m_nRowClicked, false );
        HydrogenApp *hydrogenApp = HydrogenApp::get_instance();
        hydrogenApp->m_pUndoStack->push( action );
        
        setRowSelection( RowSelection::None );
}
 
void SongEditorPatternList::patternPopup_export()
{
        setRowSelection( RowSelection::Dialog );
        HydrogenApp::get_instance()->getMainForm()->action_file_export_pattern_as( m_nRowClicked );
 
        setRowSelection( RowSelection::None );
        return;
}
 
void SongEditorPatternList::patternPopup_save()
{
        setRowSelection( RowSelection::Dialog );
        
        auto pHydrogenApp = HydrogenApp::get_instance();
        auto pCommonStrings = pHydrogenApp->getCommonStrings();
        auto pHydrogen = Hydrogen::get_instance();
        auto pSong = pHydrogen->getSong();
        auto pPattern = pSong->getPatternList()->get( m_nRowClicked );
 
        QString sPath = Files::savePatternNew( pPattern->get_name(), pPattern,
                                                                                   pSong, pHydrogen->getLastLoadedDrumkitName() );
        if ( sPath.isEmpty() ) {
                if ( QMessageBox::information(
                                 this, "Hydrogen",
                                 tr( "The pattern-file exists. \nOverwrite the existing pattern?"),
                                 QMessageBox::Ok | QMessageBox::Cancel,
                                 QMessageBox::Cancel ) != QMessageBox::Ok ) {
                        setRowSelection( RowSelection::None );
                        return;
                }
                sPath = Files::savePatternOver( pPattern->get_name(), pPattern,
                                                                                pSong, pHydrogen->getLastLoadedDrumkitName() );
        }
 
        if ( sPath.isEmpty() ) {
                QMessageBox::warning( this, "Hydrogen", tr("Could not export pattern.") );
                setRowSelection( RowSelection::None );
                return;
        }
 
        pHydrogenApp->showStatusBarMessage( tr( "Pattern saved." ) );
 
        pHydrogen->getSoundLibraryDatabase()->updatePatterns();
        
        setRowSelection( RowSelection::None );
}
 
 
 
void SongEditorPatternList::patternPopup_edit()
{
        HydrogenApp::get_instance()->getPatternEditorPanel()->show();
        HydrogenApp::get_instance()->getPatternEditorPanel()->setFocus();
}
 
 
 
void SongEditorPatternList::patternPopup_properties()
{
        
        setRowSelection( RowSelection::Dialog );
        auto pHydrogen = Hydrogen::get_instance();
        auto pPattern = pHydrogen->getSong()->getPatternList()->get( m_nRowClicked );
 
        PatternPropertiesDialog *dialog =
                new PatternPropertiesDialog( this, pPattern, m_nRowClicked, false);
        dialog->exec();
        delete dialog;
        dialog = nullptr;
 
        setRowSelection( RowSelection::None );
}
 
 
void SongEditorPatternList::acceptPatternPropertiesDialogSettings(QString newPatternName, QString newPatternInfo, QString newPatternCategory, int patternNr)
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
        PatternList *patternList = pSong->getPatternList();
        H2Core::Pattern *pattern = patternList->get( patternNr );
        pattern->set_name( newPatternName );
        pattern->set_info( newPatternInfo );
        pattern->set_category( newPatternCategory );
        pHydrogen->setIsModified( true );
        EventQueue::get_instance()->push_event( EVENT_PATTERN_MODIFIED, -1 );
        invalidateBackground();
        update();
}
 
 
void SongEditorPatternList::revertPatternPropertiesDialogSettings(QString oldPatternName, QString oldPatternInfo, QString oldPatternCategory, int patternNr)
{
        Hydrogen *pHydrogen = Hydrogen::get_instance();
        std::shared_ptr<Song> pSong = pHydrogen->getSong();
        PatternList *patternList = pSong->getPatternList();
        H2Core::Pattern *pattern = patternList->get( patternNr );
        pattern->set_name( oldPatternName );
        pattern->set_category( oldPatternCategory );
        pHydrogen->setIsModified( true );
        EventQueue::get_instance()->push_event( EVENT_PATTERN_MODIFIED, -1 );
        invalidateBackground();
        update();
}
 
 
void SongEditorPatternList::patternPopup_delete()
{
        setRowSelection( RowSelection::Dialog );
        
        auto pSong = m_pHydrogen->getSong();
        auto pPattern = pSong->getPatternList()->get( m_nRowClicked );
 
        QString patternPath =
                Files::savePatternTmp( pPattern->get_name(), pPattern, pSong,
                                                           m_pHydrogen->getLastLoadedDrumkitName() );
        if ( patternPath.isEmpty() ) {
                QMessageBox::warning( this, "Hydrogen", tr("Could not save pattern to temporary directory.") );
                setRowSelection( RowSelection::None );
                return;
        }
        QString sequencePath = Filesystem::tmp_file_path( "SEQ.xml" );
        if ( !pSong->writeTempPatternList( sequencePath ) ) {
                QMessageBox::warning( this, "Hydrogen", tr("Could not export sequence.") );
                setRowSelection( RowSelection::None );
                return;
        }
 
        SE_deletePatternFromListAction *action =
                new SE_deletePatternFromListAction( patternPath, sequencePath,
                                                                                        m_nRowClicked );
        HydrogenApp *hydrogenApp = HydrogenApp::get_instance();
        hydrogenApp->m_pUndoStack->push( action );
 
        setRowSelection( RowSelection::None );
}
 
void SongEditorPatternList::patternPopup_duplicate()
{
        setRowSelection( RowSelection::Dialog );
        
        auto pSong = m_pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        auto pPattern = pPatternList->get( m_nRowClicked );
 
        H2Core::Pattern *pNewPattern = new Pattern( pPattern );
        PatternPropertiesDialog *dialog = new PatternPropertiesDialog( this, pNewPattern, m_nRowClicked, true );
 
        if ( dialog->exec() == QDialog::Accepted ) {
                QString filePath = Files::savePatternTmp( pNewPattern->get_name(),
                                                                                                  pNewPattern, pSong,
                                                                                                  m_pHydrogen->getLastLoadedDrumkitName() );
                if ( filePath.isEmpty() ) {
                        QMessageBox::warning( this, "Hydrogen", tr("Could not save pattern to temporary directory.") );
                        setRowSelection( RowSelection::None );
                        return;
                }
                SE_duplicatePatternAction *action =
                        new SE_duplicatePatternAction( filePath, m_nRowClicked + 1 );
                HydrogenApp::get_instance()->m_pUndoStack->push( action );
        }
 
        delete dialog;
        delete pNewPattern;
 
        setRowSelection( RowSelection::None );
}
 
void SongEditorPatternList::patternPopup_fill()
{
        setRowSelection( RowSelection::Dialog );
        
        FillRange range;
        PatternFillDialog *dialog = new PatternFillDialog( this, &range );
 
        // use a PatternFillDialog to get the range and mode data
        if ( dialog->exec() == QDialog::Accepted ) {
 
                SE_fillRangePatternAction *action =
                        new SE_fillRangePatternAction( &range, m_nRowClicked );
                HydrogenApp::get_instance()->m_pUndoStack->push( action );
        }
 
        delete dialog;
 
        setRowSelection( RowSelection::None );
}
 
 
void SongEditorPatternList::fillRangeWithPattern( FillRange* pRange, int nPattern )
{
        m_pAudioEngine->lock( RIGHT_HERE );
 
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        H2Core::Pattern *pPattern = pPatternList->get( nPattern );
        std::vector<PatternList*> *pColumns = pSong->getPatternGroupVector();   // E' la lista di "colonne" di pattern
        PatternList *pColumn = nullptr;
 
        int nColumn, nColumnIndex;
        bool bHasPattern = false;
        int fromVal = pRange->fromVal - 1;
        int toVal   = pRange->toVal;
 
        // Add patternlists to PatternGroupVector as necessary
        int nDelta = toVal - pColumns->size() + 1;
 
        for ( int i = 0; i < nDelta; i++ ) {
                pColumn = new PatternList();
                pColumns->push_back( pColumn );
        }
 
        // Fill or Clear each cell in range
        for ( nColumn = fromVal; nColumn < toVal; nColumn++ ) {
 
                // expand Pattern
                pColumn = ( *pColumns )[ nColumn ];
                
                assert( pColumn );
 
                bHasPattern = false;
 
                // check whether the pattern (and column) already exists
                for ( nColumnIndex = 0; pColumn && nColumnIndex < (int)pColumn->size(); nColumnIndex++) {
 
                        if ( pColumn->get( nColumnIndex ) == pPattern ) {
                                bHasPattern = true;
                                break;
                        }
                }
 
                if ( pRange->bInsert && !bHasPattern ) {       //fill
                        pColumn->add( pPattern);
                }
                else if ( !pRange->bInsert && bHasPattern ) {  // clear
                        pColumn->del( pPattern);
                }
        }
 
                // remove all the empty patternlists at the end of the song
                for ( int i = pColumns->size() - 1; i != 0 ; i-- ) {
                        PatternList *pList = (*pColumns)[ i ];
                        int nSize = pList->size();
                        if ( nSize == 0 ) {
                                pColumns->erase( pColumns->begin() + i );
                                delete pList;
                        }
                        else {
                                break;
                        }
                }
        m_pAudioEngine->unlock();
 
 
        // Update
        m_pHydrogen->setIsModified( true );
        HydrogenApp::get_instance()->getSongEditorPanel()->updateAll();
}
 

void SongEditorPatternList::dragEnterEvent(QDragEnterEvent *event)
{
        if ( event->mimeData()->hasFormat("text/plain") ) {
                        event->acceptProposedAction();
        }
}
 
 
void SongEditorPatternList::dropEvent(QDropEvent *event)
{
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        
        QString sText = event->mimeData()->text();
        const QMimeData* mimeData = event->mimeData();
 
        auto pEv = static_cast<DropEvent*>( event );
        
        int nTargetPattern = 0;
        if(m_nGridHeight > 0)
        {
                nTargetPattern = pEv->position().y() / m_nGridHeight;
        }
        
        if( sText.startsWith("Songs:") || sText.startsWith("move instrument:") || sText.startsWith("importInstrument:")){
                event->acceptProposedAction();
                return;
        }
        
        if ( sText.startsWith("move pattern:") ) {
                QStringList tokens = sText.split( ":" );
                bool bOK = true;
 
                int nSourcePattern = tokens[1].toInt(&bOK);
                if ( ! bOK ) {
                        return;
                }
 
                if ( nSourcePattern == nTargetPattern ) {
                        event->acceptProposedAction();
                        return;
                }
 
                SE_movePatternListItemAction *action = new SE_movePatternListItemAction( nSourcePattern , nTargetPattern ) ;
                HydrogenApp::get_instance()->m_pUndoStack->push( action );
 
                event->acceptProposedAction();
        } 
        else if( sText.startsWith("file://") && mimeData->hasUrls() )
        {
                //Dragging a file from an external file manager
                PatternList *pPatternList = pSong->getPatternList();
                QList<QUrl> urlList = mimeData->urls();
 
                int successfullyAddedPattern = 0;
                
                for (int i = 0; i < urlList.size(); i++)
                {
                        QString patternFilePath = urlList.at(i).toLocalFile();
                        if( patternFilePath.endsWith(".h2pattern") )
                        {
                                Pattern* pPattern = Pattern::load_file( patternFilePath, pSong->getInstrumentList() );
                                if ( pPattern)
                                {
                                        H2Core::Pattern *pNewPattern = pPattern;
                        
                                        if(!pPatternList->check_name( pNewPattern->get_name() ) ){
                                                pNewPattern->set_name( pPatternList->find_unused_pattern_name( pNewPattern->get_name() ) );
                                        }
                                        
                                        SE_insertPatternAction* pInsertPatternAction = new SE_insertPatternAction( nTargetPattern + successfullyAddedPattern, pNewPattern );
                                        HydrogenApp::get_instance()->m_pUndoStack->push( pInsertPatternAction );
                                        
                                        successfullyAddedPattern++;
                                }
                                else
                                {
                                        ERRORLOG( QString("Error loading pattern %1").arg(patternFilePath) );
                                }
                        }
                }
        } 
        else 
        {
                QStringList tokens = sText.split( "::" );
                QString sPatternName = tokens.at( 1 );
 
                //create a unique sequencefilename
                Pattern *pPattern = pSong->getPatternList()->get( nTargetPattern );
                HydrogenApp *pHydrogenApp = HydrogenApp::get_instance();
 
                QString oldPatternName = pPattern->get_name();
 
                QString sequenceFilename = Filesystem::tmp_file_path( "SEQ.xml" );
                bool drag = false;
                if( QString( tokens.at(0) ).contains( "drag pattern" )) drag = true;
                SE_loadPatternAction *pAction = new SE_loadPatternAction( sPatternName, oldPatternName, sequenceFilename, nTargetPattern, drag );
 
                pHydrogenApp->m_pUndoStack->push( pAction );
        }
}
 
 
 
void SongEditorPatternList::movePatternLine( int nSourcePattern , int nTargetPattern )
{
                Hydrogen *pHydrogen = Hydrogen::get_instance();
 
                std::shared_ptr<Song> pSong = pHydrogen->getSong();
                PatternList *pPatternList = pSong->getPatternList();
 
 
 
                // move patterns...
                H2Core::Pattern *pSourcePattern = pPatternList->get( nSourcePattern );
                if ( nSourcePattern < nTargetPattern) {
                        for (int nPatr = nSourcePattern; nPatr < nTargetPattern; nPatr++) {
                                H2Core::Pattern *pPattern = pPatternList->get(nPatr + 1);
                                pPatternList->replace( nPatr, pPattern );
                        }
                        pPatternList->replace( nTargetPattern, pSourcePattern );
                }
                else {
                        for (int nPatr = nSourcePattern; nPatr > nTargetPattern; nPatr--) {
                                H2Core::Pattern *pPattern = pPatternList->get(nPatr - 1);
                                pPatternList->replace( nPatr, pPattern );
                        }
                        pPatternList->replace( nTargetPattern, pSourcePattern );
                }
 
                if ( pHydrogen->isPatternEditorLocked() ) {
                        pHydrogen->updateSelectedPattern();
                } else  {
                        pHydrogen->setSelectedPatternNumber( nTargetPattern );
                }
                HydrogenApp::get_instance()->getSongEditorPanel()->updateAll();
                pHydrogen->setIsModified( true );
}
 
void SongEditorPatternList::leaveEvent( QEvent* ev ) {
        UNUSED( ev );
        m_nRowHovered = -1;
        invalidateBackground();
        update();
}
 
void SongEditorPatternList::mouseMoveEvent(QMouseEvent *event)
{
        auto pEv = static_cast<MouseEvent*>( event );
 
        // Update the highlighting of the hovered row.
        if ( pEv->position().y() / m_nGridHeight != m_nRowHovered ) {
                m_nRowHovered = pEv->position().y() / m_nGridHeight;
                invalidateBackground();
                update();
        }
        
        if (!(event->buttons() & Qt::LeftButton)) {
                return;
        }
        if ( (pEv->position().y() / m_nGridHeight) == (__drag_start_position.y() / m_nGridHeight) ) {
                return;
        }
        std::shared_ptr<Song> pSong = m_pHydrogen->getSong();
        PatternList *pPatternList = pSong->getPatternList();
        int row = (__drag_start_position.y() / m_nGridHeight);
        if ( row >= (int)pPatternList->size() ) {
                return;
        }
        Pattern *pPattern = pPatternList->get( row );
        QString sName = "<unknown>";
        if ( pPattern ) {
                sName = pPattern->get_name();
        }
        QString sText = QString("move pattern:%1:%2").arg( row ).arg( sName );
 
        QDrag *pDrag = new QDrag(this);
        QMimeData *pMimeData = new QMimeData;
 
        pMimeData->setText( sText );
        pDrag->setMimeData( pMimeData);
        //drag->setPixmap(iconPixmap);
 
        m_pDragScroller->startDrag();
        pDrag->exec( Qt::CopyAction | Qt::MoveAction );
        m_pDragScroller->endDrag();
 
        QWidget::mouseMoveEvent(event);
}
 
 
void SongEditorPatternList::timelineUpdateEvent( int nEvent )
{
        HydrogenApp::get_instance()->getSongEditorPanel()->updateAll();
}
 
void SongEditorPatternList::onPreferencesChanged( H2Core::Preferences::Changes changes )
{
        if ( changes & ( H2Core::Preferences::Changes::Colors |
                                         H2Core::Preferences::Changes::Font ) ) {
                
                invalidateBackground();
                update();
        }
}
 
// ::::::::::::::::::::::::::
 
SongEditorPositionRuler::SongEditorPositionRuler( QWidget *parent )
 : QWidget( parent )
 , m_bRightBtnPressed( false )
 , m_nActiveBpmWidgetColumn( -1 )
 , m_nHoveredColumn( -1 )
 , m_hoveredRow( HoveredRow::None )
 , m_nTagHeight( 6 )
 , m_fTick( 0 )
 , m_nColumn( 0 )
{
 
        auto pPref = H2Core::Preferences::get_instance();
 
        HydrogenApp::get_instance()->addEventListener( this );
 
        m_pHydrogen = Hydrogen::get_instance();
        m_pAudioEngine = m_pHydrogen->getAudioEngine();
 
        setAttribute(Qt::WA_OpaquePaintEvent);
        setMouseTracking( true );
 
        m_nGridWidth = pPref->getSongEditorGridWidth();
 
        int nInitialWidth = SongEditor::nMargin +
                Preferences::get_instance()->getMaxBars() * m_nGridWidth;
        
        m_nActiveColumns = m_pHydrogen->getSong()->getPatternGroupVector()->size();
 
        resize( nInitialWidth, m_nMinimumHeight );
        setFixedHeight( m_nMinimumHeight );
 
        qreal pixelRatio = devicePixelRatio();
        m_pBackgroundPixmap = new QPixmap( nInitialWidth * pixelRatio, m_nMinimumHeight * pixelRatio );      // initialize the pixmap
        m_pBackgroundPixmap->setDevicePixelRatio( pixelRatio );
 
        createBackground();     // create m_backgroundPixmap pixmap
        update();
 
        m_pTimer = new QTimer(this);
        connect(m_pTimer, &QTimer::timeout, [=]() {
                if ( H2Core::Hydrogen::get_instance()->getAudioEngine()->getState() ==
                         H2Core::AudioEngine::State::Playing ) {
                        updatePosition();
                }
        });
        m_pTimer->start(200);
}
 
 
 
SongEditorPositionRuler::~SongEditorPositionRuler() {
        m_pTimer->stop();
        if ( m_pBackgroundPixmap ) {
                delete m_pBackgroundPixmap;
        }
}
 
void SongEditorPositionRuler::relocationEvent() {
        updatePosition();
}
 
void SongEditorPositionRuler::songSizeChangedEvent() {
        m_nActiveColumns = m_pHydrogen->getSong()->getPatternGroupVector()->size();
        invalidateBackground();
        update();
}
 
uint SongEditorPositionRuler::getGridWidth()
{
        return m_nGridWidth;
}
 
void SongEditorPositionRuler::setGridWidth( uint width )
{
        if ( SONG_EDITOR_MIN_GRID_WIDTH <= width && SONG_EDITOR_MAX_GRID_WIDTH >= width )
        {
                m_nGridWidth = width;
                resize( columnToX( Preferences::get_instance()->getMaxBars() ), height() );
                invalidateBackground();
                update();
        }
}
 
void SongEditorPositionRuler::invalidateBackground() {
        m_bBackgroundInvalid = true;
}
 
void SongEditorPositionRuler::createBackground()
{
        Preferences *pPref = Preferences::get_instance();
        auto pHydrogen = Hydrogen::get_instance();
        auto pSong = pHydrogen->getSong();
        auto pTimeline = pHydrogen->getTimeline();
        auto tagVector = pTimeline->getAllTags();
        
        QColor textColor( pPref->getColorTheme()->m_songEditor_textColor );
        QColor textColorAlpha( textColor );
        textColorAlpha.setAlpha( 45 );
 
        QColor backgroundColor = pPref->getColorTheme()->m_songEditor_alternateRowColor.darker( 115 );
        QColor backgroundInactiveColor = pPref->getColorTheme()->m_midLightColor;
        QColor backgroundColorTempoMarkers = backgroundColor.darker( 120 );
 
        QColor colorHighlight = pPref->getColorTheme()->m_highlightColor;
 
        QColor lineColor = pPref->getColorTheme()->m_songEditor_lineColor;
        QColor lineColorAlpha( lineColor );
        lineColorAlpha.setAlpha( 45 );
                
        // Resize pixmap if pixel ratio has changed
        qreal pixelRatio = devicePixelRatio();
        if ( m_pBackgroundPixmap->devicePixelRatio() != pixelRatio ||
                 m_pBackgroundPixmap->width() != width() ||
                 m_pBackgroundPixmap->height() != height() ) {
                delete m_pBackgroundPixmap;
                m_pBackgroundPixmap = new QPixmap( width()  * pixelRatio , height() * pixelRatio );
                m_pBackgroundPixmap->setDevicePixelRatio( pixelRatio );
        }
 
        QFont font( pPref->getApplicationFontFamily(), getPointSize( pPref->getFontSize() ) );
 
        QPainter p( m_pBackgroundPixmap );
        p.setFont( font );
 
        int nActiveWidth = columnToX( m_nActiveColumns ) + 1;
        p.fillRect( 0, 0, width(), height(), backgroundColorTempoMarkers );
        p.fillRect( 0, 25, nActiveWidth, height() - 25, backgroundColor );
        p.fillRect( nActiveWidth, 25, width() - nActiveWidth, height() - 25,
                                backgroundInactiveColor );
        char tmp[10];
        
        int nMaxPatternSequence = pPref->getMaxBars();
        
        QColor textColorGrid( textColor );
        textColorGrid.setAlpha( 200 );
        p.setPen( QPen( textColorGrid, 1, Qt::SolidLine ) );
        for ( int ii = 0; ii < nMaxPatternSequence + 1; ii++) {
                int x = columnToX( ii );
 
                if ( ( ii % 4 ) == 0 ) {
                        p.drawLine( x, height() - 14, x, height() - 1);
                }
                else {
                        p.drawLine( x, height() - 6, x, height() - 1);
                }
        }
 
        // Add every 4th number to the grid
        p.setPen( textColor );
        for (uint i = 0; i < nMaxPatternSequence + 1; i += 4) {
                uint x = columnToX( i );
 
                sprintf( tmp, "%d", i + 1 );
                if ( i < 10 ) {
                        p.drawText( x, height() / 2 + 3, m_nGridWidth, height() / 2 - 7,
                                                Qt::AlignHCenter, tmp );
                } else {
                        p.drawText( x + 2, height() / 2 + 3, m_nGridWidth * 3.5, height() / 2 - 7,
                                                Qt::AlignLeft, tmp );
                }
        }
        
        // draw tags
        p.setPen( pPref->getColorTheme()->m_accentTextColor );
        
        QFont font2( pPref->getApplicationFontFamily(), 5 );
        p.setFont( font2 );
                
        for ( const auto& ttag : tagVector ){
                int x = columnToX( ttag->nColumn ) + 4;
                QRect rect( x, height() / 2 - 1 - m_nTagHeight,
                                        m_nGridWidth - 6, m_nTagHeight );
 
                p.fillRect( rect, pPref->getColorTheme()->m_highlightColor.darker( 135 ) );
                p.drawText( rect, Qt::AlignCenter, "T");
        }
        p.setFont( font );
 
        // draw tempo content
        
        // Draw tempo marker grid.
        if ( ! pHydrogen->isTimelineEnabled() ) {
                p.setPen( textColorAlpha );
        } else {
                QColor tempoMarkerGridColor( textColor );
                tempoMarkerGridColor.setAlpha( 170 );
                p.setPen( tempoMarkerGridColor );
        }
        for (uint ii = 0; ii < nMaxPatternSequence + 1; ii++) {
                uint x = columnToX( ii );
 
                p.drawLine( x, 1, x, 4 );
                p.drawLine( x, height() / 2 - 5, x, height() / 2 );
        }
 
        // Draw tempo markers
        auto tempoMarkerVector = pTimeline->getAllTempoMarkers();
        for ( const auto& ttempoMarker : tempoMarkerVector ){
                drawTempoMarker( ttempoMarker, false, p );                               
        }
 
        p.setPen( QColor(35, 39, 51) );
        p.drawLine( 0, 0, width(), 0 );
        p.drawLine( 0, height() - 25, width(), height() - 25 );
        p.drawLine( 0, height(), width(), height() );
 
        m_bBackgroundInvalid = false;
}
 
void SongEditorPositionRuler::tempoChangedEvent( int ) {
        auto pTimeline = Hydrogen::get_instance()->getTimeline();
        if ( ! pTimeline->isFirstTempoMarkerSpecial() ) {
                return;
        }
 
        // There is just the special tempo marker -> no tempo markers set
        // by the user. In this case the special marker isn't drawn and
        // doesn't need to be update.
        if ( pTimeline->getAllTempoMarkers().size() == 1 ) {
                return;
        }
 
        invalidateBackground();
        update();
}
 
void SongEditorPositionRuler::patternModifiedEvent() {
        // This can change the size of the song and affect the position of
        // the playhead.
        update();
}
 
void SongEditorPositionRuler::playingPatternsChangedEvent() {
        // Triggered every time the column of the SongEditor grid
        // changed. Either by rolling transport or by relocation.
        update();
}
 
void SongEditorPositionRuler::leaveEvent( QEvent* ev ){
        m_nHoveredColumn = -1;
        m_hoveredRow = HoveredRow::None;
        update();
 
        QWidget::leaveEvent( ev );
}
 
void SongEditorPositionRuler::mouseMoveEvent(QMouseEvent *ev)
{
        auto pHydrogen = Hydrogen::get_instance();
 
        auto pEv = static_cast<MouseEvent*>( ev );
        
        int nColumn = std::max( xToColumn( pEv->position().x() ), 0 );
 
        HoveredRow row;
        if ( pEv->position().y() > 22 ) {
                row = HoveredRow::Ruler;
        } else if ( pEv->position().y() > 22 - 1 - m_nTagHeight ) {
                row = HoveredRow::Tag;
        } else {
                row = HoveredRow::TempoMarker;
        }
        
        if ( nColumn != m_nHoveredColumn ||
                 row != m_hoveredRow ) {
                // Cursor has moved into a region where the above caching
                // became invalid.
                m_hoveredRow = row;
                m_nHoveredColumn = nColumn;
 
                update();
        }
        
        if ( !m_bRightBtnPressed && ev->buttons() & Qt::LeftButton ) {
                // Click+drag triggers same action as clicking at new position
                mousePressEvent( ev );
        } else if ( ev->buttons() & Qt::RightButton ) {
                // Right-click+drag
                Preferences* pPref = Preferences::get_instance();
                
                if ( nColumn > (int)Hydrogen::get_instance()->getSong()->getPatternGroupVector()->size() ) {
                        pPref->setPunchOutPos(-1);
                        return;
                }
                if ( Hydrogen::get_instance()->getMode() == Song::Mode::Pattern ) {
                        return;
                }
                pPref->setPunchOutPos( nColumn - 1 );
                update();
        }
}
 
bool SongEditorPositionRuler::event( QEvent* ev ) {
        if ( ev->type() == QEvent::ToolTip ) {
                const auto helpEv = dynamic_cast<QHelpEvent*>(ev);
                showToolTip( helpEv->pos(), helpEv->globalPos() );
                return 0;
        }
 
        return QWidget::event( ev );
}
 
void SongEditorPositionRuler::songModeActivationEvent() {
        updatePosition();
        invalidateBackground();
        update();
}
 
void SongEditorPositionRuler::timelineActivationEvent() {
        invalidateBackground();
        update();
}
 
void SongEditorPositionRuler::jackTimebaseStateChangedEvent( int nState ) {
        invalidateBackground();
        update();
}
 
void SongEditorPositionRuler::updateSongEvent( int nValue ) {
 
        if ( nValue == 0 ) { // different song opened
                updatePosition();
                songSizeChangedEvent();
        }
}
 
void SongEditorPositionRuler::showToolTip( const QPoint& pos, const QPoint& globalPos ) {
        auto pHydrogen = Hydrogen::get_instance();
        auto pTimeline = pHydrogen->getTimeline();
 
        const int nColumn = std::max( xToColumn( pos.x() ), 0 );
        
        if ( pHydrogen->isTimelineEnabled() &&
                 pTimeline->isFirstTempoMarkerSpecial() &&
                 m_hoveredRow == HoveredRow::TempoMarker &&
                 pos.x() < columnToX( 1 ) ) { // first tempo marker 
                        const QString sBpm =
                                pTimeline->getTempoMarkerAtColumn( nColumn )->getPrettyString( -1 );
                QToolTip::showText( globalPos, QString( "%1: %2" )
                                                        .arg( tr( "The tempo set in the BPM widget will be used as a default for the beginning of the song. Left-click to overwrite it." ) )
                                                        .arg( sBpm ), this );
                
        }
        else if ( m_hoveredRow == HoveredRow::TempoMarker ) {
                if ( pTimeline->hasColumnTempoMarker( nColumn ) ) {
                        const QString sBpm =
                                pTimeline->getTempoMarkerAtColumn( nColumn )->getPrettyString( -1 );
                        QToolTip::showText( globalPos, sBpm, this );
                }
        }
        else if ( m_hoveredRow == HoveredRow::Tag ) {
                // Row containing the tags
                if ( pTimeline->hasColumnTag( nColumn ) ) {
                        QToolTip::showText( globalPos,
                                                                pTimeline->getTagAtColumn( nColumn ), this );
                }
        }
}
 
void SongEditorPositionRuler::showTagWidget( int nColumn )
{
        SongEditorPanelTagWidget dialog( this , nColumn );
        dialog.exec();
}
 
void SongEditorPositionRuler::showBpmWidget( int nColumn )
{
        bool bTempoMarkerPresent =
                Hydrogen::get_instance()->getTimeline()->hasColumnTempoMarker( nColumn );
        m_nActiveBpmWidgetColumn = nColumn;
        update();
        
        SongEditorPanelBpmWidget dialog( this , nColumn, bTempoMarkerPresent );
        dialog.exec();
        
        m_nActiveBpmWidgetColumn = -1;
        update();
}
 
 
void SongEditorPositionRuler::mousePressEvent( QMouseEvent *ev )
{
        auto pEv = static_cast<MouseEvent*>( ev );
 
        auto pHydrogen = Hydrogen::get_instance();
        auto pCoreActionController = pHydrogen->getCoreActionController();
                
        int nColumn = std::max( xToColumn( pEv->position().x() ), 0 );
        
        if (ev->button() == Qt::LeftButton ) {
                if ( pEv->position().y() > 22 ) {
                        // Relocate transport using position ruler
                        m_bRightBtnPressed = false;
 
                        if ( nColumn > (int) m_pHydrogen->getSong()->getPatternGroupVector()->size() ) {
                                return;
                        }
 
                        if ( m_pHydrogen->getMode() == Song::Mode::Pattern ) {
                                pCoreActionController->activateSongMode( true );
                                m_pHydrogen->setIsModified( true );
                        }
 
                        m_pHydrogen->getCoreActionController()->locateToColumn( nColumn );
                        update();
                }
                else if ( pEv->position().y() > 22 - 1 - m_nTagHeight ) {
                        showTagWidget( nColumn );
                }       
                else if ( m_pHydrogen->isTimelineEnabled() ){
                        showBpmWidget( nColumn );
                }
        }
        else if ( ev->button() == Qt::MiddleButton ) {
                showTagWidget( nColumn );
        }
        else if (ev->button() == Qt::RightButton && pEv->position().y() >= 26) {
                Preferences* pPref = Preferences::get_instance();
                if ( nColumn >= (int) m_pHydrogen->getSong()->getPatternGroupVector()->size() ) {
                        pPref->unsetPunchArea();
                        return;
                }
                if ( m_pHydrogen->getMode() == Song::Mode::Pattern ) {
                        return;
                }
                m_bRightBtnPressed = true;
                // Disable until mouse is moved
                pPref->setPunchInPos( nColumn );
                pPref->setPunchOutPos(-1);
                update();
        }
 
}
 
 
 
 
void SongEditorPositionRuler::mouseReleaseEvent(QMouseEvent *ev)
{
        UNUSED( ev );
        m_bRightBtnPressed = false;
}
 
 
void SongEditorPositionRuler::paintEvent( QPaintEvent *ev )
{
        auto pHydrogenApp = HydrogenApp::get_instance();
        auto pSongEditor = pHydrogenApp->getSongEditorPanel()->getSongEditor();
        auto pTimeline = m_pHydrogen->getTimeline();
        auto pPref = Preferences::get_instance();
        auto tempoMarkerVector = pTimeline->getAllTempoMarkers();
 
        if ( m_bBackgroundInvalid ) {
                createBackground();
        }
        
        if (!isVisible()) {
                return;
        }
        
        QColor textColor( pPref->getColorTheme()->m_songEditor_textColor );
        QColor textColorAlpha( textColor );
        textColorAlpha.setAlpha( 45 );
        QColor highlightColor = pPref->getColorTheme()->m_highlightColor;
        QColor colorHovered( highlightColor );
        colorHovered.setAlpha( 200 );
        QColor backgroundColor = pPref->getColorTheme()->m_songEditor_alternateRowColor.darker( 115 );
        QColor backgroundColorTempoMarkers = backgroundColor.darker( 120 );
 
        int nPunchInPos = Preferences::get_instance()->getPunchInPos();
        int nPunchOutPos = Preferences::get_instance()->getPunchOutPos();
 
        QPainter painter(this);
        QFont font( pPref->getApplicationFontFamily(), getPointSize( pPref->getFontSize() ) );
        qreal pixelRatio = devicePixelRatio();
        if ( pixelRatio != m_pBackgroundPixmap->devicePixelRatio() ) {
                createBackground();
        }
        QRectF srcRect(
                        pixelRatio * ev->rect().x(),
                        pixelRatio * ev->rect().y(),
                        pixelRatio * ev->rect().width(),
                        pixelRatio * ev->rect().height()
        );
        painter.drawPixmap( ev->rect(), *m_pBackgroundPixmap, srcRect );
        
        // Which tempo marker is the currently used one?
        int nCurrentTempoMarkerColumn = -1;
        for ( const auto& tempoMarker : tempoMarkerVector ) {
                if ( tempoMarker->nColumn > m_nColumn ) {
                        break;
                }
                nCurrentTempoMarkerColumn = tempoMarker->nColumn;
        }
        if ( nCurrentTempoMarkerColumn == -1 &&
                 tempoMarkerVector.size() != 0 ) {
                auto pTempoMarker = tempoMarkerVector[ tempoMarkerVector.size() - 1 ];
                if ( pTempoMarker != nullptr ) {
                        nCurrentTempoMarkerColumn = pTempoMarker->nColumn;
                }
        }
        if ( nCurrentTempoMarkerColumn != -1 ) {
                auto pTempoMarker = pTimeline->getTempoMarkerAtColumn( nCurrentTempoMarkerColumn );
                if ( pTempoMarker != nullptr ) {
                        // Reset the region and overwrite the marker's versio
                        // using normal weight.
                        const QRect rect = calcTempoMarkerRect( pTempoMarker, true );
                        painter.fillRect( rect, backgroundColorTempoMarkers );
                        drawTempoMarker( pTempoMarker, true, painter );
                }
        }
 
        // Draw playhead
        if ( m_fTick != -1 ) {
                int nX = tickToColumn( m_fTick, m_nGridWidth );
                int nShaftOffset = Skin::getPlayheadShaftOffset();
                Skin::drawPlayhead( &painter, nX, height() / 2 + 2, false );
                painter.drawLine( nX + nShaftOffset, 0, nX + nShaftOffset, height() );
        }
                        
        // Highlight hovered tick of the Timeline
        if ( m_hoveredRow == HoveredRow::Tag ||
                 ( m_hoveredRow == HoveredRow::TempoMarker &&
                   m_pHydrogen->isTimelineEnabled() ) ||
                 m_nActiveBpmWidgetColumn != -1 ) {
 
                int nColumn;
                if ( m_nActiveBpmWidgetColumn != -1 ) {
                        nColumn = m_nActiveBpmWidgetColumn;
                } else {
                        nColumn = m_nHoveredColumn;
                }
                const int x = columnToX( nColumn );
 
                // Erase background tick lines to not get any interference.
                painter.fillRect( x, 1, 1, 4,
                                                  backgroundColorTempoMarkers );
                painter.fillRect( x, height() / 2 - 5, 1, 4,
                                                  backgroundColorTempoMarkers );
 
                if ( m_hoveredRow == HoveredRow::TempoMarker ) {
                        // Erase the area of horizontal line above a tempo
                        // marker too. The associated highlight will be drawn later on.
                        painter.fillRect( x - 1, 1, m_nGridWidth - 1, 4,
                                                          backgroundColorTempoMarkers );
                }
 
                painter.setPen( QPen( highlightColor, 1 ) );
 
                painter.drawLine( x, 1, x, 4 );
                painter.drawLine( x, height() / 2 - 5, x, height() / 2 - 1 );
        }
 
        // Highlight tag
        bool bTagPresent = false;
        if ( m_hoveredRow == HoveredRow::Tag &&
                 pTimeline->hasColumnTag( m_nHoveredColumn ) ) {
 
                int x = columnToX( m_nHoveredColumn ) + 4;
                QRect rect( x, height() / 2 - 1 - m_nTagHeight,
                                        m_nGridWidth - 6, m_nTagHeight );
        
                QFont font2( pPref->getApplicationFontFamily(), 5 );
                painter.setFont( font2 );
                
                painter.fillRect( rect, pPref->getColorTheme()->m_highlightColor );
                painter.setPen( pPref->getColorTheme()->m_highlightedTextColor );
                painter.drawText( rect, Qt::AlignCenter, "T");
 
                painter.setFont( font );
                bTagPresent = true;
        }
 
        // Draw a slight highlight around the tempo marker hovered using
        // mouse or touch events. This will also redraw the
        // tempo marker to ensure it's visible (they can overlap with
        // neighboring ones and be hardly readable).
        bool bTempoMarkerPresent = false;
        if ( ! bTagPresent &&
                 ( ( m_pHydrogen->isTimelineEnabled() &&
                         m_hoveredRow == HoveredRow::TempoMarker ) ||
                   m_nActiveBpmWidgetColumn != -1 ) ) {
 
                int nColumn;
                if ( m_nActiveBpmWidgetColumn != -1 ) {
                        nColumn = m_nActiveBpmWidgetColumn;
                } else {
                        nColumn = m_nHoveredColumn;
                }
 
                if ( pTimeline->hasColumnTempoMarker( nColumn ) ||
                         ( pTimeline->isFirstTempoMarkerSpecial() &&
                           nColumn == 0 ) ) {
 
                        auto pTempoMarker = pTimeline->getTempoMarkerAtColumn( nColumn );
                        if ( pTempoMarker != nullptr ) {
 
                                const bool bEmphasize = pTempoMarker->nColumn == nCurrentTempoMarkerColumn;
                                const QRect rect = calcTempoMarkerRect( pTempoMarker, bEmphasize );
                
                                painter.fillRect( rect, backgroundColorTempoMarkers );
                                drawTempoMarker( pTempoMarker, bEmphasize, painter );
                                
                                if ( m_nActiveBpmWidgetColumn == -1 ) {
                                        painter.setPen( QPen( colorHovered, 1 ) );
                                } else {
                                        painter.setPen( QPen( highlightColor, 1 ) );
                                }
                                painter.drawRect( rect );
 
                                painter.drawLine( rect.x(), 2, rect.x() + m_nGridWidth / 2, 2 );
 
                                bTempoMarkerPresent = true;
                        }
                }
        }
 
        // Draw hovering highlights in tempo marker row
        if ( ( m_nHoveredColumn > -1 &&
                   ( ( m_hoveredRow == HoveredRow::Tag && !bTagPresent ) ||
                         ( m_hoveredRow == HoveredRow::TempoMarker &&
                           m_pHydrogen->isTimelineEnabled() &&
                           ! bTempoMarkerPresent ) ) ) ||
                 ( m_nActiveBpmWidgetColumn != -1 &&
                   ! bTempoMarkerPresent ) ) {
 
                QColor color;
                if ( m_nActiveBpmWidgetColumn == -1 ) {
                        color = colorHovered;
                } else {
                        color = highlightColor;
                }
                QPen p( color );
                p.setWidth( 1 );
                painter.setPen( p );
 
                int nCursorX;
                if ( m_nActiveBpmWidgetColumn != -1 ) {
                        nCursorX = columnToX( m_nActiveBpmWidgetColumn ) + 3;
                } else {
                        nCursorX = columnToX( m_nHoveredColumn ) + 3;
                }
 
                if ( m_hoveredRow == HoveredRow::TempoMarker ||
                         m_nActiveBpmWidgetColumn != -1 ) {
                        // Reset the background during highlight in order to
                        // indicate that no tempo marker is present in this
                        // column.
                        QRect hoveringRect( nCursorX, 6, m_nGridWidth - 5, 12 );
                        painter.fillRect( hoveringRect, backgroundColorTempoMarkers );
                        painter.drawRect( hoveringRect );
                } else {
                        painter.drawRect( nCursorX, height() / 2 - 1 - m_nTagHeight,
                                                          m_nGridWidth - 5, m_nTagHeight - 1 );
                }
        }
 
        // Draw cursor
        if ( ! pHydrogenApp->hideKeyboardCursor() && pSongEditor->hasFocus() ) {
                int nCursorX = columnToX( pSongEditor->getCursorColumn() ) + 2;
 
                QColor cursorColor = pPref->getColorTheme()->m_cursorColor;
 
                QPen p( cursorColor );
                p.setWidth( 2 );
                painter.setPen( p );
                painter.setRenderHint( QPainter::Antialiasing );
                // Aim to leave a visible gap between the border of the
                // pattern cell, and the cursor line, for consistency and
                // visibility.
                painter.drawLine( nCursorX, height() / 2 + 3,
                                                  nCursorX + m_nGridWidth - 3, height() / 2 + 3 );
                painter.drawLine( nCursorX, height() / 2 + 4,
                                                  nCursorX, height() / 2 + 5 );
                painter.drawLine( nCursorX + m_nGridWidth - 3, height() / 2 + 4,
                                                  nCursorX + m_nGridWidth - 3, height() / 2 + 5 );
                painter.drawLine( nCursorX, height() - 4,
                                                  nCursorX + m_nGridWidth - 3, height() - 4 );
                painter.drawLine( nCursorX, height() - 6,
                                                  nCursorX, height() - 5 );
                painter.drawLine( nCursorX + m_nGridWidth - 3, height() - 6,
                                                  nCursorX + m_nGridWidth - 3, height() - 5 );
        }
 
        // Faint playhead over hovered position marker.
        if ( m_nHoveredColumn > -1  &&
                 m_hoveredRow == HoveredRow::Ruler &&
                 m_nHoveredColumn <= m_nActiveColumns ) {
 
                int x = tickToColumn( m_nHoveredColumn, m_nGridWidth );
                int nShaftOffset = Skin::getPlayheadShaftOffset();
                Skin::drawPlayhead( &painter, x, height() / 2 + 2, true );
                painter.drawLine( x + nShaftOffset, 0, x + nShaftOffset, height() / 2 + 1 );
                painter.drawLine( x + nShaftOffset, height() / 2 + 2 + Skin::nPlayheadHeight,
                                                  x + nShaftOffset, height() );
        }
 
        if ( nPunchInPos <= nPunchOutPos ) {
                const int xIn = columnToX( nPunchInPos );
                const int xOut = columnToX( nPunchOutPos + 1 );
                painter.fillRect( xIn, 30, xOut-xIn+1, 12, QColor(200, 100, 100, 100) );
                QPen pen(QColor(200, 100, 100));
                painter.setPen(pen);
                painter.drawRect( xIn, 30, xOut-xIn+1, 12 );
        }
}
 
QRect SongEditorPositionRuler::calcTempoMarkerRect( std::shared_ptr<const Timeline::TempoMarker> pTempoMarker, bool bEmphasize ) const {
        assert( pTempoMarker );
 
        auto pTimeline = Hydrogen::get_instance()->getTimeline();
        auto pPref = Preferences::get_instance();
        auto weight = QFont::Normal;
        if ( bEmphasize ) {
                weight = QFont::Bold;
        }
        
        const QFont font( pPref->getApplicationFontFamily(),
                                          getPointSize( pPref->getFontSize() ), weight );
 
        const int x = columnToX( pTempoMarker->nColumn );
        int nWidth = QFontMetrics( font ).size(
                Qt::TextSingleLine, pTempoMarker->getPrettyString( 2 ) ).width();
 
        // Check whether the full width would overlap with an adjacent
        // tempo marker and trim it if necessary
        const int nCoveredNeighborColumns = 
                static_cast<int>(std::floor( static_cast<float>(nWidth) /
                                                                         static_cast<float>(m_nGridWidth) ) );
        for ( int ii = 1; ii <= nCoveredNeighborColumns; ++ii ) {
                if ( pTimeline->hasColumnTempoMarker( pTempoMarker->nColumn + ii ) ) {
                        nWidth = m_nGridWidth * ii;
                        break;
                }
        }
        
        QRect rect( x, 6, nWidth, 12 );
 
        return std::move( rect );
}
 
void SongEditorPositionRuler::drawTempoMarker( std::shared_ptr<const Timeline::TempoMarker> pTempoMarker, bool bEmphasize, QPainter& painter ) {
        assert( pTempoMarker );
 
        auto pPref = Preferences::get_instance();
        auto pHydrogen = Hydrogen::get_instance();
        auto pSong = pHydrogen->getSong();
        auto pTimeline = pHydrogen->getTimeline();
 
        // Only paint the special tempo marker in case Timeline is
        // activated.
        if ( pTempoMarker->nColumn == 0 && pTimeline->isFirstTempoMarkerSpecial() &&
                 ! pHydrogen->isTimelineEnabled() ) {
                return;
        }
                
        QFont font( pPref->getApplicationFontFamily(), getPointSize( pPref->getFontSize() ) );
                
        QRect rect = calcTempoMarkerRect( pTempoMarker, bEmphasize );
 
        // Draw an additional small horizontal line at the top of the
        // current column to better indicate the position of the tempo
        // marker (for larger float values e.g. 130.67).
        QColor textColor( pPref->getColorTheme()->m_songEditor_textColor );
 
        if ( pTempoMarker->nColumn == 0 && pTimeline->isFirstTempoMarkerSpecial() ) {
                textColor = textColor.darker( 150 );
        }
                        
        if ( ! pHydrogen->isTimelineEnabled() ) {
                QColor textColorAlpha( textColor );
                textColorAlpha.setAlpha( 45 );
                painter.setPen( textColorAlpha );
        } else {
                QColor tempoMarkerGridColor( textColor );
                tempoMarkerGridColor.setAlpha( 170 );
                painter.setPen( tempoMarkerGridColor );
        }
 
        painter.drawLine( rect.x(), 2, rect.x() + m_nGridWidth / 2, 2 );
 
        QColor tempoMarkerColor( textColor );
        if ( ! pHydrogen->isTimelineEnabled() ) {
                tempoMarkerColor.setAlpha( 45 );
        }
        painter.setPen( tempoMarkerColor );
                                
        if ( bEmphasize ) {
                font.setBold( true );
        }
        painter.setFont( font );
        painter.drawText( rect, Qt::AlignLeft | Qt::AlignVCenter,
                                          pTempoMarker->getPrettyString( 2 ) );
 
        if ( bEmphasize ) {
                font.setBold( false );
        }
        painter.setFont( font );
}
 
void SongEditorPositionRuler::updatePosition()
{
        const auto pTimeline = m_pHydrogen->getTimeline();
        const auto pPref = Preferences::get_instance();
        const auto tempoMarkerVector = pTimeline->getAllTempoMarkers();
        
        m_pAudioEngine->lock( RIGHT_HERE );
 
        const auto pTransportPos = m_pAudioEngine->getTransportPosition();
        const auto pPatternGroupVector =
                m_pHydrogen->getSong()->getPatternGroupVector();
        m_nColumn = std::max( pTransportPos->getColumn(), 0 );
 
        float fTick = static_cast<float>(m_nColumn);
 
        if ( m_pHydrogen->getMode() == Song::Mode::Pattern ) {
                fTick = -1;
        }
        else {
                // Song mode
                if ( pTransportPos->getColumn() == -1 ) {
                        // Transport reached end of song. This can mean we switched from
                        // Pattern Mode and transport wasn't started yet -> playhead at
                        // beginning or we reached the end during playback -> playhead stays
                        // at the end.
                        if ( m_pAudioEngine->isEndOfSongReached( pTransportPos ) ) {
                                fTick = pPatternGroupVector->size();
                        }
                        else {
                                fTick = 0;
                        }
                }
                else if ( pPatternGroupVector->size() > m_nColumn &&
                                  pPatternGroupVector->at( m_nColumn )->size() > 0 ) {
                        int nLength = pPatternGroupVector->at( m_nColumn )->longest_pattern_length();
                        fTick += (float)pTransportPos->getPatternTickPosition() /
                                (float)nLength;
                }
                else {
                        // Empty column. Use the default length.
                        fTick += (float)pTransportPos->getPatternTickPosition() /
                                (float)MAX_NOTES;
                }
 
                if ( fTick < 0 ) {
                        // As some variables of the audio engine are initialized as or
                        // reset to -1 we ensure this does not affect the position of
                        // the playhead in the SongEditor.
                        fTick = 0;
                }
        }
 
        m_pAudioEngine->unlock();
 
        if ( fTick != m_fTick ) {
                float fDiff = static_cast<float>(m_nGridWidth) * (fTick - m_fTick);
 
                m_fTick = fTick;
                int nX = tickToColumn( m_fTick, m_nGridWidth );
 
                QRect updateRect( nX -2, 0, 4 + Skin::nPlayheadWidth, height() );
                update( updateRect );
                if ( fDiff > 1.0 || fDiff < -1.0 ) {
                        // New cursor is far enough away from the old one that the single update rect won't cover both. So
                        // update at the old location as well.
                        updateRect.translate( -fDiff, 0 );
                        update( updateRect );
                }
 
                auto pSongEditorPanel = HydrogenApp::get_instance()->getSongEditorPanel();
                if ( pSongEditorPanel != nullptr ) {
                        pSongEditorPanel->getSongEditor()->updatePosition( fTick );
                        pSongEditorPanel->getPlaybackTrackWaveDisplay()->updatePosition( fTick );
                        pSongEditorPanel->getAutomationPathView()->updatePosition( fTick );
                }
        }
}
 
int SongEditorPositionRuler::columnToX( int nColumn ) const {
        return SongEditor::nMargin + nColumn * static_cast<int>(m_nGridWidth);
}
int SongEditorPositionRuler::xToColumn( int nX ) const {
        return static_cast<int>(
                ( static_cast<float>(nX) - static_cast<float>(SongEditor::nMargin)) /
                static_cast<float>(m_nGridWidth));
}
int SongEditorPositionRuler::tickToColumn( float fTick, uint nGridWidth ) {
        return static_cast<int>( static_cast<float>(SongEditor::nMargin) + 1 +
                                                                   fTick * static_cast<float>(nGridWidth) -
                                                         static_cast<float>(Skin::nPlayheadWidth) / 2 );
}
 
 
void SongEditorPositionRuler::timelineUpdateEvent( int nValue )
{
        invalidateBackground();
        update();
}
 
void SongEditorPositionRuler::onPreferencesChanged( H2Core::Preferences::Changes changes )
{
        if ( changes & ( H2Core::Preferences::Changes::Colors |
                                         H2Core::Preferences::Changes::Font ) ) {
                         
                resize( SongEditor::nMargin +
                                Preferences::get_instance()->getMaxBars() * m_nGridWidth, height() );
                invalidateBackground();
                update();
        }
}