/*
 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 <QPalette>
#include <qwt_scale_map.h>

#include "barchart.h"

BarChart::BarChart(ChannelManager* channelMan)
{
 _channelMan = channelMan;
 setSpacing(0);
}

void BarChart::resample()
{
 setSamples(chartData());
}

QVector<double> BarChart::chartData() const
{
 unsigned numChannels = _channelMan->numOfChannels();
 unsigned numOfSamples = _channelMan->numOfSamples();
 QVector<double> data(numChannels);
 for (unsigned i = 0; i < numChannels; i++)
 {
 data[i] = _channelMan->channelBuffer(i)->sample(numOfSamples-1);
 }
 return data;
}

QwtColumnSymbol* BarChart::specialSymbol(int sampleIndex, const QPointF& sample) const
{
 unsigned numChannels = _channelMan->numOfChannels();
 if (sampleIndex < 0 || sampleIndex > (int) numChannels)
 {
 return NULL;
 }

 auto info = _channelMan->infoModel();
 auto color = info->color(sampleIndex);

 QwtColumnSymbol* symbol = new QwtColumnSymbol(QwtColumnSymbol::Box);
 symbol->setLineWidth(1);
 symbol->setFrameStyle(QwtColumnSymbol::Plain);
 symbol->setPalette(QPalette(color));

 return symbol;
}

void BarChart::drawSample(
 QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap,
 const QRectF &canvasRect, const QwtInterval &boundingInterval,
 int index, const QPointF &sample ) const
{
 QwtPlotBarChart::drawSample(painter, xMap, yMap, canvasRect, boundingInterval, index, sample);

 // calculate bar size
 const double barWidth = sampleWidth(xMap, canvasRect.width(),
 boundingInterval.width(), sample.y());
 const double x = xMap.transform( sample.x() );
 const double x1 = x - 0.5 * barWidth;
 // const double x2 = x + 0.5 * barWidth;

 const double y1 = yMap.transform(baseline());
 const double y2 = yMap.transform(sample.y());
 const double barHeight = fabs(y2 - y1);

 // create and calculate text size
 const auto valueStr = QString::number(sample.y());
 auto valueText = QwtText(valueStr, QwtText::PlainText);
 const auto textSize = valueText.textSize();
 auto r = QRectF(x1, y2, barWidth, textSize.height());
 if (y2 > y1) r.moveBottom(y2);

 // display text if there is enough space
 if (barHeight >= textSize.height() && barWidth >= textSize.width())
 {
 valueText.draw(painter, r);
 }
}