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** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
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#include "qtmenu_p.h"
#include "qtmenuitemcontainer_p.h"
#include "qtaction_p.h"
#include "qtmenupopupwindow_p.h"

#include <qdebug.h>
#include <qabstractitemmodel.h>
#include <qcursor.h>
#include <private/qguiapplication_p.h>
#include <QtGui/qpa/qplatformtheme.h>
#include <QtGui/qpa/qplatformmenu.h>
#include <qquickitem.h>

QT_BEGIN_NAMESPACE

/*!
  \class QtMenu
  \internal
 */

/*!
  \qmltype MenuPrivate
  \instantiates QtMenu
  \internal
  \inqmlmodule QtQuick.Controls 1.0
 */

/*!
    \qmlproperty readonly list Menu::items
    \default

    The list of items in the menu.

    \sa MenuItem, MenuSeparator
*/

/*!
    \qmlproperty bool Menu::visible

    Whether the menu should be visible. This is only enabled when the menu is used as
    a submenu.
*/

/*!
    \qmlproperty string Menu::title

    Title for the menu as a submenu or in a menubar.

    Mnemonics are supported by prefixing the shortcut letter with \&.
    For instance, \c "\&File" will bind the \c Alt-F shortcut to the
    \c "File" menu. Note that not all platforms support mnemonics.
*/

/*!
    \qmlproperty bool Menu::enabled

    Whether the menu is enabled, and responsive to user interaction as a submenu.
*/

/*!
    \qmlproperty url Menu::iconSource

    Sets the icon file or resource url for the menu icon as a submenu.

    \sa iconName
*/

/*!
    \qmlproperty string Menu::iconName

    Sets the icon name for the menu icon. This will pick the icon
    with the given name from the current theme. Only works as a submenu.

    \sa iconSource
*/

/*!
    \qmlmethod void Menu::popup()

    Opens this menu under the mouse cursor.
    It can block on some platforms, so test it accordingly.
*/

/*!
    \qmlproperty var Menu::model
*/

QtMenu::QtMenu(QObject *parent)
    : QtMenuText(parent),
      m_itemsCount(0),
      m_selectedIndex(-1),
      m_parentWindow(0),
      m_minimumWidth(0),
      m_popupWindow(0),
      m_menuContentItem(0),
      m_popupVisible(false),
      m_containersCount(0)
{
    connect(this, SIGNAL(__textChanged()), this, SIGNAL(titleChanged()));

    m_platformMenu = QGuiApplicationPrivate::platformTheme()->createPlatformMenu();
    if (m_platformMenu) {
        connect(m_platformMenu, SIGNAL(aboutToHide()), this, SLOT(__closeMenu()));
        if (platformItem())
            platformItem()->setMenu(m_platformMenu);
    }
}

QtMenu::~QtMenu()
{
    delete m_platformMenu;
    m_platformMenu = 0;
}

void QtMenu::updateText()
{
    if (m_platformMenu)
        m_platformMenu->setText(this->text());
    QtMenuText::updateText();
}

void QtMenu::setMinimumWidth(int w)
{
    if (w == m_minimumWidth)
        return;

    m_minimumWidth = w;
    if (m_platformMenu)
        m_platformMenu->setMinimumWidth(w);
}

void QtMenu::setFont(const QFont &arg)
{
    if (m_platformMenu)
        m_platformMenu->setFont(arg);
}

void QtMenu::setSelectedIndex(int index)
{
    if (m_selectedIndex == index)
        return;

    m_selectedIndex = index;
    emit __selectedIndexChanged();
}

void QtMenu::updateSelectedIndex()
{
    if (QtMenuItem *menuItem = qobject_cast<QtMenuItem*>(sender())) {
        int index = indexOfMenuItem(menuItem);
        setSelectedIndex(index);
    }
}

QtMenuItems QtMenu::menuItems()
{
    return QtMenuItems(this, 0, &QtMenu::append_menuItems, &QtMenu::count_menuItems, &QtMenu::at_menuItems, 0);
}

QQuickWindow *QtMenu::findParentWindow()
{
    if (!m_parentWindow) {
        QQuickItem *parentAsItem = qobject_cast<QQuickItem *>(parent());
        m_parentWindow = visualItem() ? visualItem()->window() :    // Menu as menu item case
                         parentAsItem ? parentAsItem->window() : 0; //Menu as context menu/popup case
    }
    return m_parentWindow;
}

void QtMenu::popup()
{
    QPoint mousePos = QCursor::pos();
    if (QQuickWindow *parentWindow = findParentWindow())
        mousePos = parentWindow->mapFromGlobal(mousePos);

    __popup(mousePos.x(), mousePos.y());
}

void QtMenu::__popup(qreal x, qreal y, int atItemIndex)
{
    if (popupVisible())
        __closeMenu();

    setPopupVisible(true);

    QtMenuBase *atItem = menuItemAtIndex(atItemIndex);

    QQuickWindow *parentWindow = findParentWindow();

    if (m_platformMenu) {
        QPointF screenPosition(x, y);
        if (visualItem())
            screenPosition = visualItem()->mapToScene(screenPosition);
        m_platformMenu->showPopup(parentWindow, screenPosition.toPoint(), atItem ? atItem->platformItem() : 0);
    } else {
        m_popupWindow = new QtMenuPopupWindow();
        m_popupWindow->setParentWindow(parentWindow);
        m_popupWindow->setMenuContentItem(m_menuContentItem);
        connect(m_popupWindow, SIGNAL(visibleChanged(bool)), this, SLOT(windowVisibleChanged(bool)));

        if (parentWindow) {
            if (visualItem()) {
                QPointF pos = visualItem()->mapToItem(parentWindow->contentItem(), QPointF(x, y));
                x = pos.x();
                y = pos.y();
            }

            x += parentWindow->geometry().left();
            y += parentWindow->geometry().top();
        }

        QQuickItem *visualItem = atItem ? atItem->visualItem() : 0;
        if (visualItem) {
            QPointF pos = visualItem->position();
            x -= pos.x();
            y -= pos.y();
            m_popupWindow->setItemAt(visualItem);
        }

        qreal initialWidth = qMax(qreal(1), m_menuContentItem->width());
        qreal initialHeight = qMax(qreal(1), m_menuContentItem->height());

        if (!qobject_cast<QtMenuPopupWindow *>(parentWindow)) // No need for parent menu windows
            if (QQuickItem *mg = parentWindow->mouseGrabberItem())
                mg->ungrabMouse();

        m_popupWindow->setGeometry(x, y, initialWidth, initialHeight);
        m_popupWindow->show();
        m_popupWindow->setMouseGrabEnabled(true); // Needs to be done after calling show()
        m_popupWindow->setKeyboardGrabEnabled(true);
    }
}

void QtMenu::setMenuContentItem(QQuickItem *item)
{
    if (m_menuContentItem != item)
        m_menuContentItem = item;
}

void QtMenu::setPopupVisible(bool v)
{
    if (m_popupVisible != v) {
        m_popupVisible = v;
        emit popupVisibleChanged();
    }
}

void QtMenu::__closeMenu()
{
    setPopupVisible(false);
    if (m_popupWindow)
        m_popupWindow->setVisible(false);
    m_parentWindow = 0;
    emit __menuClosed();
}

void QtMenu::__dismissMenu()
{
    QtMenuPopupWindow *topMenuWindow = m_popupWindow;
    while (topMenuWindow) {
        QtMenuPopupWindow *pw = qobject_cast<QtMenuPopupWindow *>(topMenuWindow->transientParent());
        if (!pw)
            topMenuWindow->dismissMenu();
        topMenuWindow = pw;
    }
}

void QtMenu::windowVisibleChanged(bool v)
{
    if (!v) {
        if (qobject_cast<QtMenuPopupWindow *>(m_popupWindow->transientParent())) {
            m_popupWindow->transientParent()->setMouseGrabEnabled(true);
            m_popupWindow->transientParent()->setKeyboardGrabEnabled(true);
        }
        m_popupWindow->deleteLater();
        m_popupWindow = 0;
        __closeMenu();
    }
}

void QtMenu::itemIndexToListIndex(int itemIndex, int *listIndex, int *containerIndex) const
{
    *listIndex = -1;
    QtMenuItemContainer *container = 0;
    while (itemIndex >= 0 && ++*listIndex < m_menuItems.count())
        if ((container = qobject_cast<QtMenuItemContainer *>(m_menuItems[*listIndex])))
            itemIndex -= container->items().count();
        else
            --itemIndex;

    if (container)
        *containerIndex = container->items().count() + itemIndex;
    else
        *containerIndex = -1;
}

int QtMenu::itemIndexForListIndex(int listIndex) const
{
    int index = 0;
    int i = 0;
    while (i < listIndex && i < m_menuItems.count())
        if (QtMenuItemContainer *container = qobject_cast<QtMenuItemContainer *>(m_menuItems[i++]))
            index += container->items().count();
        else
            ++index;

    return index;
}

QtMenuBase *QtMenu::nextMenuItem(QtMenu::MenuItemIterator *it) const
{
    if (it->containerIndex != -1) {
        QtMenuItemContainer *container = qobject_cast<QtMenuItemContainer *>(m_menuItems[it->index]);
        if (++it->containerIndex < container->items().count())
            return container->items()[it->containerIndex];
    }

    if (++it->index < m_menuItems.count()) {
        if (QtMenuItemContainer *container = qobject_cast<QtMenuItemContainer *>(m_menuItems[it->index])) {
            it->containerIndex = 0;
            return container->items()[0];
        } else {
            it->containerIndex = -1;
            return m_menuItems[it->index];
        }
    }

    return 0;
}

QtMenuBase *QtMenu::menuItemAtIndex(int index) const
{
    if (0 <= index && index < m_itemsCount) {
        if (!m_containersCount) {
            return m_menuItems[index];
        } else if (m_containersCount == 1 && m_menuItems.count() == 1) {
            QtMenuItemContainer *container = qobject_cast<QtMenuItemContainer *>(m_menuItems[0]);
            return container->items()[index];
        } else {
            int containerIndex;
            int i;
            itemIndexToListIndex(index, &i, &containerIndex);
            if (containerIndex != -1) {
                QtMenuItemContainer *container = qobject_cast<QtMenuItemContainer *>(m_menuItems[i]);
                return container->items()[containerIndex];
            } else {
                return m_menuItems[i];
            }
        }
    }

    return 0;
}

bool QtMenu::contains(QtMenuBase *item)
{
    if (item->container())
        return item->container()->items().contains(item);

    return m_menuItems.contains(item);
}

int QtMenu::indexOfMenuItem(QtMenuBase *item) const
{
    if (!item)
        return -1;
    if (item->container()) {
        int containerIndex = m_menuItems.indexOf(item->container());
        if (containerIndex == -1)
            return -1;
        int index = item->container()->items().indexOf(item);
        return index == -1 ? -1 : itemIndexForListIndex(containerIndex) + index;
    } else {
        int index = m_menuItems.indexOf(item);
        return index == -1 ? -1 : itemIndexForListIndex(index);
    }
}

QtMenuItem *QtMenu::addItem(QString title)
{
    QtMenuItem *item = new QtMenuItem(this);
    item->setText(title);
    insertItem(m_itemsCount, item);
    return item;
}

void QtMenu::insertItem(int index, QtMenuBase *menuItem)
{
    if (!menuItem)
        return;
    int itemIndex;
    if (m_containersCount) {
        QtMenuItemContainer *container = menuItem->parent() != this ? m_containers[menuItem->parent()] : 0;
        if (container) {
            container->insertItem(index, menuItem);
            itemIndex = itemIndexForListIndex(m_menuItems.indexOf(container)) + index;
        } else {
            itemIndex = itemIndexForListIndex(index);
            m_menuItems.insert(itemIndex, menuItem);
        }
    } else {
        itemIndex = index;
        m_menuItems.insert(index, menuItem);
    }

    setupMenuItem(menuItem, itemIndex);
    emit itemsChanged();
}

void QtMenu::removeItem(QtMenuBase *menuItem)
{
    if (!menuItem)
        return;
    menuItem->setParentMenu(0);

    QtMenuItemContainer *container = menuItem->parent() != this ? m_containers[menuItem->parent()] : 0;
    if (container)
        container->removeItem(menuItem);
    else
        m_menuItems.removeOne(menuItem);

    --m_itemsCount;
    emit itemsChanged();
}

void QtMenu::clear()
{
    m_containers.clear();
    m_containersCount = 0;

    while (!m_menuItems.empty())
        delete m_menuItems.takeFirst();
    m_itemsCount = 0;
}

void QtMenu::setupMenuItem(QtMenuBase *item, int platformIndex)
{
    item->setParentMenu(this);
    if (m_platformMenu) {
        QPlatformMenuItem *before = 0;
        if (platformIndex != -1)
            before = m_platformMenu->menuItemAt(platformIndex);
        m_platformMenu->insertMenuItem(item->platformItem(), before);
    }
    ++m_itemsCount;
}

void QtMenu::append_menuItems(QtMenuItems *list, QObject *o)
{
    if (QtMenu *menu = qobject_cast<QtMenu *>(list->object)) {
        Q_ASSERT(o->parent() == menu);

        if (QtMenuBase *menuItem = qobject_cast<QtMenuBase *>(o)) {
            menu->m_menuItems.append(menuItem);
            menu->setupMenuItem(menuItem);
        } else {
            QtMenuItemContainer *menuItemContainer = new QtMenuItemContainer(menu);
            menu->m_menuItems.append(menuItemContainer);
            menu->m_containers.insert(o, menuItemContainer);
            menuItemContainer->setParentMenu(menu);
            ++menu->m_containersCount;
            foreach (QObject *child, o->children()) {
                if (QtMenuBase *item = qobject_cast<QtMenuBase *>(child)) {
                    menuItemContainer->insertItem(-1, item);
                    menu->setupMenuItem(item);
                }
            }
        }
    }
}

int QtMenu::count_menuItems(QtMenuItems *list)
{
    if (QtMenu *menu = qobject_cast<QtMenu *>(list->object))
        return menu->m_itemsCount;

    return 0;
}

QObject *QtMenu::at_menuItems(QtMenuItems *list, int index)
{
    if (QtMenu *menu = qobject_cast<QtMenu *>(list->object))
        return menu->menuItemAtIndex(index);

    return 0;
}

QT_END_NAMESPACE