#include "pieslice_p.h"
#include "pieslicelabel_p.h"
#include "piepresenter_p.h"
#include "qpieseries.h"
#include "qpieslice.h"
#include <QPainter>
#include <QDebug>
#include <qmath.h>
#include <QGraphicsSceneEvent>
#include <QTime>

QTCOMMERCIALCHART_BEGIN_NAMESPACE

QPointF offset(qreal angle, qreal length)
{
    qreal dx = qSin(angle*(PI/180)) * length;
    qreal dy = qCos(angle*(PI/180)) * length;
    return QPointF(dx, -dy);
}

PieSlice::PieSlice(QGraphicsItem* parent)
    :QGraphicsObject(parent),
    m_slicelabel(new PieSliceLabel(this)),
    m_startAngle(0),
    m_angleSpan(0),
    m_isExploded(false),
    m_explodeDistance(0)
{
    setAcceptHoverEvents(true);
    setAcceptedMouseButtons(Qt::LeftButton);
}

PieSlice::~PieSlice()
{

}

QRectF PieSlice::boundingRect() const
{
    return m_path.boundingRect();
}

QPainterPath PieSlice::shape() const
{
    return m_path;
}

void PieSlice::paint(QPainter* painter, const QStyleOptionGraphicsItem* /*option*/, QWidget* /*widget*/)
{
    painter->setPen(m_pen);
    painter->setBrush(m_brush);
    painter->drawPath(m_path);
}

void PieSlice::hoverEnterEvent(QGraphicsSceneHoverEvent* /*event*/)
{
    emit hoverEnter();
}

void PieSlice::hoverLeaveEvent(QGraphicsSceneHoverEvent* /*event*/)
{
    emit hoverLeave();
}

void PieSlice::mousePressEvent(QGraphicsSceneMouseEvent* /*event*/)
{
    emit clicked();
}

void PieSlice::setPieRect(QRectF rect)
{
    m_pieRect = rect;
}

void PieSlice::updateGeometry()
{
    if (!m_pieRect.isValid() || m_pieRect.isEmpty())
        return;

    prepareGeometryChange();

    // calculate center angle
    qreal centerAngle = m_startAngle + (m_angleSpan/2);

    // adjust rect for exploding
    QRectF rect = m_pieRect;
    if (m_isExploded) {
        qreal dx = qSin(centerAngle*(PI/180)) * m_explodeDistance;
        qreal dy = -qCos(centerAngle*(PI/180)) * m_explodeDistance;
        rect.translate(dx, dy);
    }

    // update slice path
    // TODO: draw the shape so that it might have a hole in the center
    QPainterPath path;
    path.moveTo(rect.center());
    path.arcTo(rect, -m_startAngle + 90, -m_angleSpan);
    path.closeSubpath();
    m_path = path;

    // update label position
    qreal radius = rect.height() / 2;
    QPointF edgeCenter = rect.center() + offset(centerAngle, radius + 5);
    m_slicelabel->setArmStartPoint(edgeCenter);
    m_slicelabel->setArmAngle(centerAngle);
    m_slicelabel->updateGeometry();
    m_slicelabel->update();

    //qDebug() << "PieSlice::updateGeometry" << m_slicelabel->text() << boundingRect() << m_angle << m_span;
}

void PieSlice::updateData(const QPieSlice* sliceData)
{
    // TODO: compare what has changes to avoid unneccesary geometry updates

    m_startAngle = sliceData->startAngle();
    m_angleSpan = sliceData->m_angleSpan;
    m_isExploded = sliceData->isExploded();
    m_explodeDistance = sliceData->explodeDistance(); // TODO: expose to public API
    m_pen = sliceData->pen();
    m_brush = sliceData->brush();

    m_slicelabel->setVisible(sliceData->isLabelVisible());
    m_slicelabel->setText(sliceData->label());
    m_slicelabel->setPen(sliceData->labelPen());
    m_slicelabel->setFont(sliceData->labelFont());
    m_slicelabel->setArmLength(sliceData->labelArmLength());

    updateGeometry();
    update();
}

#include "moc_pieslice_p.cpp"

QTCOMMERCIALCHART_END_NAMESPACE