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#include "qquickapplicationwindow_p.h"

#include <QtQuick/private/qquickitem_p.h>
#include <QtQuick/private/qquickitemchangelistener_p.h>

QT_BEGIN_NAMESPACE

/*!
    \qmltype ApplicationWindow
    \inherits Window
    \instantiates QQuickApplicationWindow
    \inqmlmodule QtQuick.Controls
    \ingroup application
    \brief Provides a top-level application window.

    ApplicationWindow is a \l Window which makes it convenient to add
    a \l header and \l footer item to the window.

    \note By default, an ApplicationWindow is not visible.
*/

class QQuickApplicationWindowPrivate : public QQuickItemChangeListener
{
    Q_DECLARE_PUBLIC(QQuickApplicationWindow)

public:
    QQuickApplicationWindowPrivate() : complete(false), header(Q_NULLPTR), footer(Q_NULLPTR) { }

    void relayout();

    void itemImplicitWidthChanged(QQuickItem *item) Q_DECL_OVERRIDE;
    void itemImplicitHeightChanged(QQuickItem *item) Q_DECL_OVERRIDE;

    bool complete;
    QQuickItem *header;
    QQuickItem *footer;
    QQuickApplicationWindow *q_ptr;
};

void QQuickApplicationWindowPrivate::relayout()
{
    Q_Q(QQuickApplicationWindow);
    QQuickItem *content = q->contentItem();
    qreal hh = header ? header->height() : 0;
    qreal fh = footer ? footer->height() : 0;

    content->setY(hh);
    content->setHeight(q->height() - hh - fh);

    if (header) {
        header->setY(-hh);
        QQuickItemPrivate *p = QQuickItemPrivate::get(header);
        if (!p->widthValid) {
            header->setWidth(q->width());
            p->widthValid = false;
        }
    }

    if (footer) {
        footer->setY(content->height());
        QQuickItemPrivate *p = QQuickItemPrivate::get(footer);
        if (!p->widthValid) {
            footer->setWidth(q->width());
            p->widthValid = false;
        }
    }
}

void QQuickApplicationWindowPrivate::itemImplicitWidthChanged(QQuickItem *item)
{
    Q_UNUSED(item);
    relayout();
}

void QQuickApplicationWindowPrivate::itemImplicitHeightChanged(QQuickItem *item)
{
    Q_UNUSED(item);
    relayout();
}

QQuickApplicationWindow::QQuickApplicationWindow(QWindow *parent) :
    QQuickWindowQmlImpl(parent), d_ptr(new QQuickApplicationWindowPrivate)
{
    d_ptr->q_ptr = this;
}

QQuickApplicationWindow::~QQuickApplicationWindow()
{
    Q_D(QQuickApplicationWindow);
    if (d->header)
        QQuickItemPrivate::get(d->header)->removeItemChangeListener(d, QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
    if (d->footer)
        QQuickItemPrivate::get(d->footer)->removeItemChangeListener(d, QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
}

/*!
    \qmlproperty Item QtQuick.Controls::ApplicationWindow::header

    A header item for the window, for example a title bar, menu or tool-bar.
    By default this property is empty, no header will be shown.

    \sa footer
*/
QQuickItem *QQuickApplicationWindow::header() const
{
    Q_D(const QQuickApplicationWindow);
    return d->header;
}

void QQuickApplicationWindow::setHeader(QQuickItem *header)
{
    Q_D(QQuickApplicationWindow);
    if (d->header != header) {
        delete d->header;
        d->header = header;
        if (header) {
            header->setParentItem(contentItem());
            QQuickItemPrivate *p = QQuickItemPrivate::get(header);
            p->addItemChangeListener(d, QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
            if (qFuzzyIsNull(header->z()))
                header->setZ(1);
            if (isComponentComplete())
                d->relayout();
        }
        emit headerChanged();
    }
}

/*!
    \qmlproperty Item QtQuick.Controls::ApplicationWindow::footer

    A footer item for the window, for example a status bar or menu.
    By default this property is empty, no footer will be shown.

    \sa header
*/
QQuickItem *QQuickApplicationWindow::footer() const
{
    Q_D(const QQuickApplicationWindow);
    return d->footer;
}

void QQuickApplicationWindow::setFooter(QQuickItem *footer)
{
    Q_D(QQuickApplicationWindow);
    if (d->footer != footer) {
        delete d->footer;
        d->footer = footer;
        if (footer) {
            footer->setParentItem(contentItem());
            QQuickItemPrivate *p = QQuickItemPrivate::get(footer);
            p->addItemChangeListener(d, QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
            if (qFuzzyIsNull(footer->z()))
                footer->setZ(1);
            if (isComponentComplete())
                d->relayout();
        }
        emit footerChanged();
    }
}

bool QQuickApplicationWindow::isComponentComplete() const
{
    Q_D(const QQuickApplicationWindow);
    return d->complete;
}

void QQuickApplicationWindow::componentComplete()
{
    Q_D(QQuickApplicationWindow);
    d->complete = true;
    QQuickWindowQmlImpl::componentComplete();
}

void QQuickApplicationWindow::resizeEvent(QResizeEvent *event)
{
    Q_D(QQuickApplicationWindow);
    QQuickWindowQmlImpl::resizeEvent(event);
    d->relayout();
}

QT_END_NAMESPACE