#include <qglobal.h>
#include <qtimer.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_canvas.h>
#include <qwt_plot_layout.h>
#include <qwt_scale_widget.h>
#include <qwt_scale_draw.h>
#include "scrollzoomer.h"
#include "randomplot.h"

const unsigned int c_rangeMax = 1000;

class Zoomer: public ScrollZoomer
{
public:
    Zoomer( QWidget *canvas ):
        ScrollZoomer( canvas )
    {
#if 0
        setRubberBandPen( QPen( Qt::red, 2, Qt::DotLine ) );
#else
        setRubberBandPen( QPen( Qt::red ) );
#endif
    }

    virtual QwtText trackerTextF( const QPointF &pos ) const
    {
        QColor bg( Qt::white );

        QwtText text = QwtPlotZoomer::trackerTextF( pos );
        text.setBackgroundBrush( QBrush( bg ) );
        return text;
    }

    virtual void rescale()
    {
        QwtScaleWidget *scaleWidget = plot()->axisWidget( yAxis() );
        QwtScaleDraw *sd = scaleWidget->scaleDraw();

        double minExtent = 0.0;
        if ( zoomRectIndex() > 0 )
        {
            // When scrolling in vertical direction
            // the plot is jumping in horizontal direction
            // because of the different widths of the labels
            // So we better use a fixed extent.

            minExtent = sd->spacing() + sd->maxTickLength() + 1;
            minExtent += sd->labelSize(
                scaleWidget->font(), c_rangeMax ).width();
        }

        sd->setMinimumExtent( minExtent );

        ScrollZoomer::rescale();
    }
};

RandomPlot::RandomPlot( QWidget *parent ):
    IncrementalPlot( parent ),
    d_timer( 0 ),
    d_timerCount( 0 )
{
    setFrameStyle( QFrame::NoFrame );
    setLineWidth( 0 );

    plotLayout()->setAlignCanvasToScales( true );

    QwtPlotGrid *grid = new QwtPlotGrid;
    grid->setMajorPen( Qt::gray, 0, Qt::DotLine );
    grid->attach( this );

    setCanvasBackground( QColor( 29, 100, 141 ) ); // nice blue

    setAxisScale( QwtAxis::xBottom, 0, c_rangeMax );
    setAxisScale( QwtAxis::yLeft, 0, c_rangeMax );

    replot();

    // enable zooming

    ( void ) new Zoomer( canvas() );
}

QSize RandomPlot::sizeHint() const
{
    return QSize( 540, 400 );
}

void RandomPlot::appendPoint()
{
    double x = qrand() % c_rangeMax;
    x += ( qrand() % 100 ) / 100;

    double y = qrand() % c_rangeMax;
    y += ( qrand() % 100 ) / 100;

    IncrementalPlot::appendPoint( QPointF( x, y ) );

    if ( --d_timerCount <= 0 )
        stop();
}

void RandomPlot::append( int timeout, int count )
{
    if ( !d_timer )
    {
        d_timer = new QTimer( this );
        connect( d_timer, SIGNAL( timeout() ), SLOT( appendPoint() ) );
    }

    d_timerCount = count;

    Q_EMIT running( true );
    d_timeStamp.start();

    QwtPlotCanvas *plotCanvas = qobject_cast<QwtPlotCanvas *>( canvas() );
    plotCanvas->setPaintAttribute( QwtPlotCanvas::BackingStore, false );

    d_timer->start( timeout );
}

void RandomPlot::stop()
{
    Q_EMIT elapsed( d_timeStamp.elapsed() );

    if ( d_timer )
    {
        d_timer->stop();
        Q_EMIT running( false );
    }

    QwtPlotCanvas *plotCanvas = qobject_cast<QwtPlotCanvas *>( canvas() );
    plotCanvas->setPaintAttribute( QwtPlotCanvas::BackingStore, true );
}

void RandomPlot::clear()
{
    clearPoints();
    replot();
}
