#include "plot.h"
#include "settings.h"
#include <qwt_date.h>
#include <qwt_date_scale_draw.h>
#include <qwt_date_scale_engine.h>
#include <qwt_plot_panner.h>
#include <qwt_plot_magnifier.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_layout.h>

Plot::Plot( QWidget *parent ):
    QwtPlot( parent )
{
    setAutoFillBackground( true );
    setPalette( Qt::darkGray );
    setCanvasBackground( Qt::white );

    plotLayout()->setAlignCanvasToScales( true );

    initAxis( QwtPlot::yLeft, "Local Time", Qt::LocalTime );
    initAxis( QwtPlot::yRight, 
        "Coordinated Universal Time ( UTC )", Qt::UTC );

    QwtPlotPanner *panner = new QwtPlotPanner( canvas() );
    QwtPlotMagnifier *magnifier = new QwtPlotMagnifier( canvas() );

    for ( int axis = 0; axis < QwtPlot::axisCnt; axis++ )
    {
        const bool on = axis == QwtPlot::yLeft ||
            axis == QwtPlot::yRight;

        enableAxis( axis, on );
        panner->setAxisEnabled( axis, on );
        magnifier->setAxisEnabled( axis, on );
    }

    QwtPlotGrid *grid = new QwtPlotGrid();
    grid->setMajorPen( Qt::black, 0, Qt::SolidLine );
    grid->setMinorPen( Qt::gray, 0 , Qt::SolidLine );
    grid->enableX( false );
    grid->enableXMin( false );
    grid->enableY( true );
    grid->enableYMin( true );

    grid->attach( this );
}

void Plot::initAxis( int axis, 
    const QString& title, Qt::TimeSpec timeSpec )
{
    setAxisTitle( axis, title );

    QwtDateScaleDraw *scaleDraw = new QwtDateScaleDraw( timeSpec );
    QwtDateScaleEngine *scaleEngine = new QwtDateScaleEngine( timeSpec );

#if 0
    if ( timeSpec == Qt::LocalTime )
    {
        scaleDraw->setTimeSpec( Qt::OffsetFromUTC );
        scaleDraw->setUtcOffset( 10 );

        scaleEngine->setTimeSpec( Qt::OffsetFromUTC );
        scaleEngine->setUtcOffset( 10 );
    }
#endif
    setAxisScaleDraw( axis, scaleDraw );
    setAxisScaleEngine( axis, scaleEngine );
}

void Plot::applySettings( const Settings &settings )
{
    applyAxisSettings( QwtPlot::yLeft, settings );
    applyAxisSettings( QwtPlot::yRight, settings );

    replot();
}

void Plot::applyAxisSettings( int axis, const Settings &settings )
{
    QwtDateScaleEngine *scaleEngine = 
        static_cast<QwtDateScaleEngine *>( axisScaleEngine( axis ) );

    scaleEngine->setMaxWeeks( settings.maxWeeks );
    setAxisMaxMinor( axis, settings.maxMinorSteps );
    setAxisMaxMajor( axis, settings.maxMajorSteps );


    setAxisScale( axis, QwtDate::toDouble( settings.startDateTime ), 
        QwtDate::toDouble( settings.endDateTime ) );
}