/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */

/*
    Rosegarden
    A MIDI and audio sequencer and musical notation editor.
    Copyright 2000-2011 the Rosegarden development team.
 
    Other copyrights also apply to some parts of this work.  Please
    see the AUTHORS file and individual file headers for details.
 
    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.  See the file
    COPYING included with this distribution for more information.
*/


#include "AudioSegmentResizeFromStartCommand.h"

#include "base/Composition.h"
#include "base/RealTime.h"
#include "base/Segment.h"
#include <QObject>


namespace Rosegarden
{

AudioSegmentResizeFromStartCommand::AudioSegmentResizeFromStartCommand(Segment *segment,
        timeT newStartTime) :
        NamedCommand(tr("Resize Segment")),
        m_segment(segment),
        m_newSegment(0),
        m_detached(false),
        m_oldStartTime(segment->getStartTime()),
        m_newStartTime(newStartTime)
{}

AudioSegmentResizeFromStartCommand::~AudioSegmentResizeFromStartCommand()
{
    if (!m_detached)
        delete m_segment;
    else
        delete m_newSegment;
}

void
AudioSegmentResizeFromStartCommand::execute()
{
    Composition *c = m_segment->getComposition();

    if (!m_newSegment) {
        RealTime oldRT = c->getElapsedRealTime(m_oldStartTime);
        RealTime newRT = c->getElapsedRealTime(m_newStartTime);

        m_newSegment = new Segment(*m_segment);
        m_newSegment->setStartTime(m_newStartTime);

        // Compute an audio start time that will keep the audio exactly where
        // it was in time.
        RealTime audioStartTime = 
            m_segment->getAudioStartTime() - (oldRT - newRT);

        // Do not allow a negative audio start time.
        // ??? This is a stopgap measure as the audio segment preview code 
        //   will crash if the audio start time is negative.  Need to fix the
        //   preview code, then check to see if the playback code works
        //   properly given a negative start time.  Then this can be removed.
        if (audioStartTime <= RealTime::zeroTime)
            m_newSegment->setAudioStartTime(RealTime::zeroTime);
        else
            m_newSegment->setAudioStartTime(
                m_segment->getAudioStartTime() - (oldRT - newRT));
    }

    c->addSegment(m_newSegment);
    m_newSegment->setEndMarkerTime(m_segment->getEndMarkerTime());
    c->detachSegment(m_segment);

    m_detached = false;
}

void
AudioSegmentResizeFromStartCommand::unexecute()
{
    Composition *c = m_newSegment->getComposition();
    c->addSegment(m_segment);
    c->detachSegment(m_newSegment);

    m_detached = true;
}

}