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** Foundation and appearing in the file LICENSE.LGPL included in the
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#include "crumblepath.h"
#include "stylehelper.h"

#include <QtCore/QList>
#include <QtGui/QHBoxLayout>
#include <QtGui/QPushButton>
#include <QtGui/QMenu>
#include <QtGui/QStyle>
#include <QtGui/QResizeEvent>
#include <QtGui/QPainter>
#include <QtGui/QImage>

#include <qtcassert.h>

namespace Utils {

static const int ArrowBorderSize = 12;

class CrumblePathButton : public QPushButton
{
public:
    enum SegmentType {
        LastSegment = 1,
        MiddleSegment = 2,
        FirstSegment = 4
    };

    explicit CrumblePathButton(const QString &title, QWidget *parent = 0);
    void setSegmentType(int type);
    void select(bool s);
    void setData(QVariant data);
    QVariant data() const;
protected:
    void paintEvent(QPaintEvent *);
    void mouseMoveEvent(QMouseEvent *e);
    void leaveEvent(QEvent *);
    void mousePressEvent(QMouseEvent *e);
    void mouseReleaseEvent(QMouseEvent *e);

private:
    void tintImages();

private:
    bool m_isHovering;
    bool m_isPressed;
    bool m_isSelected;
    bool m_isEnd;
    QColor m_baseColor;
    QImage m_segment;
    QImage m_segmentEnd;
    QImage m_segmentSelected;
    QImage m_segmentSelectedEnd;
    QImage m_segmentHover;
    QImage m_segmentHoverEnd;
    QImage m_triangleIcon;
    QPoint m_textPos;

    QVariant m_data;
};

CrumblePathButton::CrumblePathButton(const QString &title, QWidget *parent)
    : QPushButton(title, parent), m_isHovering(false), m_isPressed(false), m_isSelected(false), m_isEnd(true)
{
    setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Fixed);
    setToolTip(title);
    setMinimumHeight(24);
    setMaximumHeight(24);
    setMouseTracking(true);
    m_textPos.setX(18);
    m_textPos.setY(height());
    m_baseColor = StyleHelper::baseColor();

    m_segment = QImage(":/utils/images/crumblepath-segment.png");
    m_segmentSelected = QImage(":/utils/images/crumblepath-segment-selected.png");
    m_segmentHover = QImage(":/utils/images/crumblepath-segment-hover.png");
    m_segmentEnd = QImage(":/utils/images/crumblepath-segment-end.png");
    m_segmentSelectedEnd = QImage(":/utils/images/crumblepath-segment-selected-end.png");
    m_segmentHoverEnd = QImage(":/utils/images/crumblepath-segment-hover-end.png");
    m_triangleIcon = QImage(":/utils/images/triangle_vert.png");

    tintImages();
}

void CrumblePathButton::paintEvent(QPaintEvent *)
{
    QPainter p(this);
    QRect geom(0, 0, geometry().width(), geometry().height());

    if (StyleHelper::baseColor() != m_baseColor) {
        m_baseColor = StyleHelper::baseColor();
        tintImages();
    }

    if (m_isEnd) {
        if (m_isPressed || m_isSelected) {
            Utils::StyleHelper::drawCornerImage(m_segmentSelectedEnd, &p, geom, 2, 0, 2, 0);
        } else if (m_isHovering) {
            Utils::StyleHelper::drawCornerImage(m_segmentHoverEnd, &p, geom, 2, 0, 2, 0);
        } else {
            Utils::StyleHelper::drawCornerImage(m_segmentEnd, &p, geom, 2, 0, 2, 0);
        }
    } else {
        if (m_isPressed || m_isSelected) {
            Utils::StyleHelper::drawCornerImage(m_segmentSelected, &p, geom, 2, 0, 12, 0);
        } else if (m_isHovering) {
            Utils::StyleHelper::drawCornerImage(m_segmentHover, &p, geom, 2, 0, 12, 0);
        } else {
            Utils::StyleHelper::drawCornerImage(m_segment, &p, geom, 2, 0, 12, 0);
        }
    }
    p.setPen(StyleHelper::panelTextColor());
    QFontMetrics fm(p.font());
    QString textToDraw = fm.elidedText(text(), Qt::ElideRight, geom.width() - m_textPos.x());

    p.drawText(QRectF(m_textPos.x(), 4, geom.width(), geom.height()), textToDraw);

    if (menu()) {
        p.drawImage(geom.width() - m_triangleIcon.width() - 6, geom.center().y() - m_triangleIcon.height()/2, m_triangleIcon);
    }
}

void CrumblePathButton::tintImages()
{
    StyleHelper::tintImage(m_segmentEnd, m_baseColor);
    StyleHelper::tintImage(m_segmentSelectedEnd, m_baseColor);
    StyleHelper::tintImage(m_segmentHoverEnd, m_baseColor);
    StyleHelper::tintImage(m_segmentSelected, m_baseColor);
    StyleHelper::tintImage(m_segmentHover, m_baseColor);
    StyleHelper::tintImage(m_segment, m_baseColor);
}

void CrumblePathButton::leaveEvent(QEvent *e)
{
    QPushButton::leaveEvent(e);
    m_isHovering = false;
    update();
}

void CrumblePathButton::mouseMoveEvent(QMouseEvent *e)
{
    QPushButton::mouseMoveEvent(e);
    m_isHovering = true;
    update();
}

void CrumblePathButton::mousePressEvent(QMouseEvent *e)
{
    QPushButton::mousePressEvent(e);
    m_isPressed = true;
    update();
}

void CrumblePathButton::mouseReleaseEvent(QMouseEvent *e)
{
    QPushButton::mouseReleaseEvent(e);
    m_isPressed = false;
    update();
}

void CrumblePathButton::select(bool s)
{
    m_isSelected = s;
    update();
}

void CrumblePathButton::setSegmentType(int type)
{
    bool useLeftPadding = !(type & FirstSegment);
    m_isEnd = (type & LastSegment);
    m_textPos.setX(useLeftPadding ? 18 : 4);
}

void CrumblePathButton::setData(QVariant data)
{
    m_data = data;
}

QVariant CrumblePathButton::data() const
{
    return m_data;
}

///////////////////////////////////////////////////////////////////////////////

struct CrumblePathPrivate {
    explicit CrumblePathPrivate(CrumblePath *q);

    QColor m_baseColor;
    QList<CrumblePathButton*> m_buttons;
    QWidget *m_background;
};

CrumblePathPrivate::CrumblePathPrivate(CrumblePath *q) :
    m_baseColor(StyleHelper::baseColor()),
    m_background(new QWidget(q))
{
}

//
// CrumblePath
//
CrumblePath::CrumblePath(QWidget *parent) :
    QWidget(parent), d(new CrumblePathPrivate(this))
{
    setMinimumHeight(25);
    setMaximumHeight(25);
    setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Minimum);

    setBackgroundStyle();
    d->m_background->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Preferred);
}

CrumblePath::~CrumblePath()
{
    qDeleteAll(d->m_buttons);
    d->m_buttons.clear();
}

void CrumblePath::selectIndex(int index)
{
    if ((index > -1) && (index < d->m_buttons.length()))
        d->m_buttons[index]->select(true);
}

QVariant CrumblePath::dataForIndex(int index) const
{
    if ((index > -1) && (index < d->m_buttons.length()))
        return d->m_buttons[index]->data();
    return QVariant();
}

void CrumblePath::setBackgroundStyle()
{
    d->m_background->setStyleSheet("QWidget { background-color:" + d->m_baseColor.name() + ";}");
}

void CrumblePath::pushElement(const QString &title, const QVariant data)
{
    CrumblePathButton *newButton = new CrumblePathButton(title, this);
    newButton->hide();
    connect(newButton, SIGNAL(clicked()), SLOT(mapClickToIndex()));

    int segType = CrumblePathButton::MiddleSegment;
    if (!d->m_buttons.isEmpty()) {
        if (d->m_buttons.length() == 1)
            segType = segType | CrumblePathButton::FirstSegment;
        d->m_buttons.last()->setSegmentType(segType);
    } else {
        segType = CrumblePathButton::FirstSegment | CrumblePathButton::LastSegment;
        newButton->setSegmentType(segType);
    }
    newButton->setData(data);
    d->m_buttons.append(newButton);

    resizeButtons();
}

void CrumblePath::addChild(const QString &title, const QVariant data)
{
    QTC_ASSERT(d->m_buttons.count()>0,return);

    QPushButton *lastButton = d->m_buttons.last();

    QMenu *childList = lastButton->menu();
    if (childList == 0)
        childList = new QMenu(lastButton);

    QAction *childAction = new QAction(title, lastButton);
    childAction->setData(data);
    connect(childAction, SIGNAL(triggered()), this, SLOT(mapClickToIndex()));
    childList->addAction(childAction);
    lastButton->setMenu(childList);
}

void CrumblePath::popElement()
{
    QWidget *last = d->m_buttons.last();
    d->m_buttons.removeLast();
    last->setParent(0);
    last->deleteLater();

    int segType = CrumblePathButton::MiddleSegment | CrumblePathButton::LastSegment;
    if (!d->m_buttons.isEmpty()) {
        if (d->m_buttons.length() == 1)
            segType = CrumblePathButton::FirstSegment | CrumblePathButton::LastSegment;
        d->m_buttons.last()->setSegmentType(segType);
    }
    resizeButtons();
}

void CrumblePath::clear()
{
    while (!d->m_buttons.isEmpty()) {
        popElement();
    }
}

void CrumblePath::resizeEvent(QResizeEvent *)
{
    resizeButtons();
}

void CrumblePath::resizeButtons()
{
    int totalWidthLeft = width();

    if (d->m_buttons.length() >= 1) {
        QPoint nextElementPosition(0,0);

        d->m_buttons[0]->raise();
        // rearrange all items so that the first item is on top (added last).

        // compute relative sizes
        QList <int> sizes;
        int totalSize = 0;
        for(int i = 0; i < d->m_buttons.length() ; ++i) {
            CrumblePathButton *button = d->m_buttons[i];

            QFontMetrics fm(button->font());
            int originalSize = ArrowBorderSize + fm.width(button->text()) + ArrowBorderSize + 12;
            sizes << originalSize;
            totalSize += originalSize - ArrowBorderSize;
        }

        for (int i = 0; i < d->m_buttons.length() ; ++i) {
            CrumblePathButton *button = d->m_buttons[i];

            int candidateSize = (sizes[i]*totalWidthLeft)/totalSize;
            if (candidateSize < ArrowBorderSize)
                candidateSize = ArrowBorderSize;
            if (candidateSize > sizes[i]*1.3)
                candidateSize = sizes[i]*1.3;


            button->setMinimumWidth(candidateSize);
            button->setMaximumWidth(candidateSize);
            button->move(nextElementPosition);

            nextElementPosition.rx() += button->width() - ArrowBorderSize;

            button->show();
            if (i > 0)
                button->stackUnder(d->m_buttons[i - 1]);
        }

    }

    d->m_background->setGeometry(0,0, width(), height());
    d->m_background->update();
}

void CrumblePath::mapClickToIndex()
{
    QObject *element = sender();
    if (QString("QAction") == element->metaObject()->className()) {
        emit elementClicked(static_cast<QAction *>(element)->data().toInt());
    } else
        if (QString("QPushButton") == element->metaObject()->className()) {
            emit elementClicked(static_cast<CrumblePathButton *>(element)->data().toInt());
        }
}

void CrumblePath::paintEvent(QPaintEvent *event)
{
    if (StyleHelper::baseColor() != d->m_baseColor) {
        d->m_baseColor = StyleHelper::baseColor();
        setBackgroundStyle();
    }

    QWidget::paintEvent(event);
}

} // namespace Utils