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#include "RowTimelinePropertyGraph.h"
#include "RowTimeline.h"
#include "RowTree.h"
#include "Ruler.h"
#include "TimelineGraphicsScene.h"
#include "Bindings/ITimelineItemProperty.h"

RowTimelinePropertyGraph::RowTimelinePropertyGraph(QObject *parent)
    : QObject(parent)
{
    m_rowTimeline = static_cast<RowTimeline *>(parent);
}

void RowTimelinePropertyGraph::paintGraphs(QPainter *painter, const QRectF &rect)
{
    m_rect = rect;
    m_propBinding = m_rowTimeline->rowTree()->propBinding();

    // Animate alpha 0..255 while expanding
    int alpha = 255 * (m_rect.height() - TimelineConstants::ROW_H)
            / (TimelineConstants::ROW_H_EXPANDED - TimelineConstants::ROW_H);
    alpha = std::max(0, alpha);

    if (alpha == 0)
        return;

    // Available line colors
    QColor colors[6] = { QColor(255, 0, 0, alpha), QColor(0, 255, 0, alpha),
                         QColor(0, 0, 255, alpha), QColor(255, 255, 0, alpha),
                         QColor(255, 0, 255, alpha), QColor(0, 255, 255, alpha) };

    long channelCount = m_propBinding->GetChannelCount();

    // Don't want to overflow the color array
    if (channelCount <= 6) {
        // For each channel graph it.
        for (long i = 0; i < channelCount; ++i)
            paintSingleChannel(painter, i, colors[i]);
    }
}

void RowTimelinePropertyGraph::paintSingleChannel(QPainter *painter, long inChannelIndex,
                                                  const QColor &inColor)
{
    float maxVal = m_propBinding->GetMaximumValue();
    float minVal = m_propBinding->GetMinimumValue();

    double timelineScale = m_rowTimeline->rowTree()->m_scene->ruler()->timelineScale();

    // Step in pixels
    int interval = 5;
    // Margin at top & bottom of graph
    float marginY = 10;
    float graphY = m_rect.y() + marginY;
    float graphHeight = m_rect.height() - marginY * 2;

    QPainterPath path;
    for (int i = 0; i < m_rect.width(); i += interval) {
        // Value time in ms
        long time = i / (TimelineConstants::RULER_MILLI_W * timelineScale);
        float value = m_propBinding->GetChannelValueAtTime(inChannelIndex, time);
        float yPos = graphY + (1.0 - (value - minVal) / (maxVal - minVal)) * graphHeight;

        if (i == 0)
            path.moveTo(m_rect.x() + i, yPos);
        else
            path.lineTo(m_rect.x() + i, yPos);
    }

    painter->setPen(QPen(inColor, 2));
    painter->drawPath(path);
}