/*

  Copyright © 2017 Hasan Yavuz Özderya

  This file is part of serialplot.

  serialplot is free software: you can redistribute it and/or modify

  it under the terms of the GNU General Public License as published by

  the Free Software Foundation, either version 3 of the License, or

  (at your option) any later version.

  serialplot 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 serialplot.  If not, see <http://www.gnu.org/licenses/>.

*/

#include <QRectF>

#include <QKeySequence>

#include <QColor>

#include <qwt_symbol.h>

#include <qwt_plot_curve.h>

#include <math.h>

#include <algorithm>

#include "plot.h"

#include "utils.h"

static const int SYMBOL_SHOW_AT_WIDTH = 5;

static const int SYMBOL_SIZE_MAX = 7;

Plot::Plot(QWidget* parent) :

    QwtPlot(parent),

    zoomer(this->canvas(), false),

    sZoomer(this, &zoomer)

{

    isAutoScaled = true;

    symbolSize = 0;

    numOfSamples = 1;

    showSymbols = Plot::ShowSymbolsAuto;

    QObject::connect(&zoomer, &Zoomer::unzoomed, this, &Plot::unzoomed);

    zoomer.setZoomBase();

    grid.attach(this);

    legend.attach(this);

    showGrid(false);

    darkBackground(false);

    snapshotOverlay = NULL;

    connect(&zoomer, &QwtPlotZoomer::zoomed,

            [this](const QRectF &rect)

            {

                onXScaleChanged();

            });

    connect(this, &QwtPlot::itemAttached,

            [this](QwtPlotItem *plotItem, bool on)

            {

                if (symbolSize) updateSymbols();

            });

    // init demo indicator

    QwtText demoText(" DEMO RUNNING ");  // looks better with spaces

    demoText.setColor(QColor("white"));

    demoText.setBackgroundBrush(Qt::darkRed);

    demoText.setBorderRadius(4);

    demoText.setRenderFlags(Qt::AlignLeft | Qt::AlignBottom);

    demoIndicator.setText(demoText);

    demoIndicator.hide();

    demoIndicator.attach(this);

    // init no channels are visible indicator

    QwtText noChannelText(" No Visible Channels ");

    noChannelText.setColor(QColor("white"));

    noChannelText.setBackgroundBrush(Qt::darkBlue);

    noChannelText.setBorderRadius(4);

    noChannelText.setRenderFlags(Qt::AlignHCenter | Qt::AlignVCenter);

    noChannelIndicator.setText(noChannelText);

    noChannelIndicator.hide();

    noChannelIndicator.attach(this);

}

Plot::~Plot()

{

    }

    snapshotOverlay = new PlotSnapshotOverlay(this->canvas(), color);

    connect(snapshotOverlay, &PlotSnapshotOverlay::done,

            [this]()

            {

                delete snapshotOverlay;

                snapshotOverlay = NULL;

            });

}

void Plot::setSymbols(ShowSymbols shown)

{

    showSymbols = shown;

    if (showSymbols == Plot::ShowSymbolsAuto)

    {

        calcSymbolSize();

    }

    else if (showSymbols == Plot::ShowSymbolsShow)

    {

        symbolSize = SYMBOL_SIZE_MAX;

    }

    else

    {

        symbolSize = 0;

    }

    updateSymbols();

    replot();

}

void Plot::onXScaleChanged()

{

    if (showSymbols == Plot::ShowSymbolsAuto)

    {

        calcSymbolSize();

        updateSymbols();

    }

}

void Plot::calcSymbolSize()

{

    auto sw = axisWidget(QwtPlot::xBottom);

    auto paintDist = sw->scaleDraw()->scaleMap().pDist();

    auto scaleDist = sw->scaleDraw()->scaleMap().sDist();

    auto fullScaleDist = zoomer.zoomBase().width();

    auto zoomRate = fullScaleDist / scaleDist;

    int symDisPx = round(paintDist / samplesInView);

    if (symDisPx < SYMBOL_SHOW_AT_WIDTH)

    {

        symbolSize = 0;

    }

    else

    {

        symbolSize = std::min(SYMBOL_SIZE_MAX, symDisPx-SYMBOL_SHOW_AT_WIDTH+1);

    }

}

void Plot::updateSymbols()

{

    const QwtPlotItemList curves = itemList( QwtPlotItem::Rtti_PlotCurve );

    if (curves.size() > 0)

    {

        for (int i = 0; i < curves.size(); i++)

        {

            QwtSymbol* symbol = NULL;

            QwtPlotCurve* curve = static_cast<QwtPlotCurve*>(curves[i]);

            if (symbolSize)

            {

                symbol = new QwtSymbol(QwtSymbol::Ellipse,

                                       canvasBackground(),

                                       curve->pen(),

                                       QSize(symbolSize, symbolSize));

            }

            curve->setSymbol(symbol);

        }

    }

}

void Plot::resizeEvent(QResizeEvent * event)

{

    QwtPlot::resizeEvent(event);

    onXScaleChanged();

}

void Plot::setNumOfSamples(unsigned value)

{

    numOfSamples = value;

    onXScaleChanged();

}

void Plot::setPlotWidth(double width)

{

    zoomer.setHViewSize(width);

}

    friend class PlotManager;

public:

    enum ShowSymbols

    {

        ShowSymbolsAuto,

        ShowSymbolsShow,

        ShowSymbolsHide

    };

    Plot(QWidget* parent = 0);

    ~Plot();

    static QColor makeColor(unsigned int channelIndex);

public slots:

    void showGrid(bool show = true);

    void showMinorGrid(bool show = true);

    void showLegend(bool show = true);

    void showDemoIndicator(bool show = true);

    void showNoChannel(bool show = true);

    void unzoom();

    void darkBackground(bool enabled = true);

    void setYAxis(bool autoScaled, double yMin = 0, double yMax = 1);

    void setXAxis(double xMin, double xMax);

    void setSymbols(ShowSymbols shown);

    /**

     * Displays an animation for snapshot.

     *

     * @param light show a light colored (white) animation or the opposite

     */

    void flashSnapshotOverlay(bool light);

    void setNumOfSamples(unsigned value);

    void setPlotWidth(double width);

protected:

    /// update the display of symbols depending on `symbolSize`

    void updateSymbols();

private:

    bool isAutoScaled;

    double yMin, yMax;

    double _xMin, _xMax;

    unsigned numOfSamples;

    int symbolSize;

    Zoomer zoomer;

    ScaleZoomer sZoomer;

    QwtPlotGrid grid;

    PlotSnapshotOverlay* snapshotOverlay;

    QwtPlotLegendItem legend;

    QwtPlotTextLabel demoIndicator;

    QwtPlotTextLabel noChannelIndicator;

    ShowSymbols showSymbols;

    void resetAxes();

    void resizeEvent(QResizeEvent * event);

    void calcSymbolSize();

private slots:

    void unzoomed();

    void onXScaleChanged();

};

#endif // PLOT_H