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#include "qcocoaaccessibility.h"
#include "qcocoaaccessibilityelement.h"
#include <qaccessible.h>
#include <qaccessible2.h>
#include <private/qcore_mac_p.h>

#ifndef QT_NO_COCOA_ACCESSIBILITY

QCococaAccessibility::QCococaAccessibility()
{

}

QCococaAccessibility::~QCococaAccessibility()
{

}

void QCococaAccessibility::notifyAccessibilityUpdate(QAccessibleEvent *event)
{
    QObject *object = event->object();
    if (!object)
        return;

    QAccessibleInterface *interface = QAccessible::queryAccessibleInterface(object);
    if (!interface)
        return;

    switch (event->type()) {
        case QAccessible::ValueChanged:
        case QAccessible::TextInserted :
        case QAccessible::TextRemoved :
        case QAccessible::TextUpdated : {
            QCocoaAccessibleElement *element = [QCocoaAccessibleElement elementWithInterface : interface parent : nil];
            NSAccessibilityPostNotification(element, NSAccessibilityValueChangedNotification);
        break; }

        default:
            delete interface;
        break;
    }
}

void QCococaAccessibility::setRootObject(QObject *o)
{
    Q_UNUSED(o)
}

void QCococaAccessibility::initialize()
{

}

void QCococaAccessibility::cleanup()
{

}

namespace QCocoaAccessible {

typedef QMap<QAccessible::Role, NSString *> QMacAccessibiltyRoleMap;
Q_GLOBAL_STATIC(QMacAccessibiltyRoleMap, qMacAccessibiltyRoleMap);

static void populateRoleMap()
{
    QMacAccessibiltyRoleMap &roleMap = *qMacAccessibiltyRoleMap();
    roleMap[QAccessible::MenuItem] = NSAccessibilityMenuItemRole;
    roleMap[QAccessible::MenuBar] = NSAccessibilityMenuBarRole;
    roleMap[QAccessible::ScrollBar] = NSAccessibilityScrollBarRole;
    roleMap[QAccessible::Grip] = NSAccessibilityGrowAreaRole;
    roleMap[QAccessible::Window] = NSAccessibilityWindowRole;
    roleMap[QAccessible::Dialog] = NSAccessibilityWindowRole;
    roleMap[QAccessible::AlertMessage] = NSAccessibilityWindowRole;
    roleMap[QAccessible::ToolTip] = NSAccessibilityWindowRole;
    roleMap[QAccessible::HelpBalloon] = NSAccessibilityWindowRole;
    roleMap[QAccessible::PopupMenu] = NSAccessibilityMenuRole;
    roleMap[QAccessible::Application] = NSAccessibilityApplicationRole;
    roleMap[QAccessible::Pane] = NSAccessibilityGroupRole;
    roleMap[QAccessible::Grouping] = NSAccessibilityGroupRole;
    roleMap[QAccessible::Separator] = NSAccessibilitySplitterRole;
    roleMap[QAccessible::ToolBar] = NSAccessibilityToolbarRole;
    roleMap[QAccessible::PageTab] = NSAccessibilityRadioButtonRole;
    roleMap[QAccessible::ButtonMenu] = NSAccessibilityMenuButtonRole;
    roleMap[QAccessible::ButtonDropDown] = NSAccessibilityPopUpButtonRole;
    roleMap[QAccessible::SpinBox] = NSAccessibilityIncrementorRole;
    roleMap[QAccessible::Slider] = NSAccessibilitySliderRole;
    roleMap[QAccessible::ProgressBar] = NSAccessibilityProgressIndicatorRole;
    roleMap[QAccessible::ComboBox] = NSAccessibilityPopUpButtonRole;
    roleMap[QAccessible::RadioButton] = NSAccessibilityRadioButtonRole;
    roleMap[QAccessible::CheckBox] = NSAccessibilityCheckBoxRole;
    roleMap[QAccessible::StaticText] = NSAccessibilityStaticTextRole;
    roleMap[QAccessible::Table] = NSAccessibilityTableRole;
    roleMap[QAccessible::StatusBar] = NSAccessibilityStaticTextRole;
    roleMap[QAccessible::Column] = NSAccessibilityColumnRole;
    roleMap[QAccessible::ColumnHeader] = NSAccessibilityColumnRole;
    roleMap[QAccessible::Row] = NSAccessibilityRowRole;
    roleMap[QAccessible::RowHeader] = NSAccessibilityRowRole;
    roleMap[QAccessible::Cell] = NSAccessibilityTextFieldRole;
    roleMap[QAccessible::PushButton] = NSAccessibilityButtonRole;
    roleMap[QAccessible::EditableText] = NSAccessibilityTextFieldRole;
    roleMap[QAccessible::Link] = NSAccessibilityTextFieldRole;
    roleMap[QAccessible::Indicator] = NSAccessibilityValueIndicatorRole;
    roleMap[QAccessible::Splitter] = NSAccessibilitySplitGroupRole;
    roleMap[QAccessible::List] = NSAccessibilityListRole;
    roleMap[QAccessible::ListItem] = NSAccessibilityStaticTextRole;
    roleMap[QAccessible::Cell] = NSAccessibilityStaticTextRole;
    roleMap[QAccessible::Client] = NSAccessibilityGroupRole;
}

/*
    Returns a Mac accessibility role for the given interface, or
    NSAccessibilityUnknownRole if no role mapping is found.
*/
NSString *macRole(QAccessibleInterface *interface)
{
    QAccessible::Role qtRole = interface->role();
    QMacAccessibiltyRoleMap &roleMap = *qMacAccessibiltyRoleMap();

    if (roleMap.isEmpty())
        populateRoleMap();

    // MAC_ACCESSIBILTY_DEBUG() << "role for" << interface.object() << "interface role" << hex << qtRole;

    if (roleMap.contains(qtRole)) {
       // MAC_ACCESSIBILTY_DEBUG() << "return" <<  roleMap[qtRole];
        if (roleMap[qtRole] == NSAccessibilityTextFieldRole && interface->state().multiLine)
            return NSAccessibilityTextAreaRole;
        return roleMap[qtRole];
    }

    // MAC_ACCESSIBILTY_DEBUG() << "return NSAccessibilityUnknownRole";
    return NSAccessibilityUnknownRole;
}

/*
    Mac accessibility supports ignoring elements, which means that
    the elements are still present in the accessibility tree but is
    not used by the screen reader.
*/
bool shouldBeIgnrored(QAccessibleInterface *interface)
{
    // Mac accessibility does not have an attribute that corresponds to the Invisible/Offscreen
    // state. Ignore interfaces with those flags set.
    const QAccessible::State state = interface->state();
    if (state.invisible ||
        state.offscreen)
        return true;

    // Some roles are not interesting. In particular, container roles should be
    // ignored in order to flatten the accessibility tree as seen by the user.
    const QAccessible::Role role = interface->role();
    if (role == QAccessible::Border ||      // QFrame
        role == QAccessible::Application || // We use the system-provided application element.
        role == QAccessible::MenuItem ||    // The system also provides the menu items.
        role == QAccessible::ToolBar)       // Access the tool buttons directly.
        return true;

    NSString *mac_role = macRole(interface);
    if (mac_role == NSAccessibilityWindowRole || // We use the system-provided window elements.
        mac_role == NSAccessibilityGroupRole ||
        mac_role == NSAccessibilityUnknownRole)
        return true;

    // Client is a generic role returned by plain QWidgets or other
    // widgets that does not have separate QAccessible interface, such
    // as the TabWidget. Return false unless macRole gives the interface
    // a special role.
    if (role == QAccessible::Client && mac_role == NSAccessibilityUnknownRole)
        return true;

    if (QObject * const object = interface->object()) {
        const QString className = QLatin1String(object->metaObject()->className());

        // VoiceOver focusing on tool tips can be confusing. The contents of the
        // tool tip is available through the description attribute anyway, so
        // we disable accessibility for tool tips.
        if (className == QLatin1String("QTipLabel"))
            return true;
    }

    return false;
}

/*
    Translates a predefined QAccessibleActionInterface action to a Mac action constant.
    Returns 0 if the Qt Action has no mac equivalent. Ownership of the NSString is
    not transferred.
*/
NSString *getTranslatedAction(const QString &qtAction)
{
    if (qtAction == QAccessibleActionInterface::pressAction())
        return NSAccessibilityPressAction;
    else if (qtAction == QAccessibleActionInterface::increaseAction())
        return NSAccessibilityIncrementAction;
    else if (qtAction == QAccessibleActionInterface::decreaseAction())
        return NSAccessibilityDecrementAction;
    else if (qtAction == QAccessibleActionInterface::showMenuAction())
        return NSAccessibilityShowMenuAction;
    else if (qtAction == QAccessibleActionInterface::setFocusAction()) // Not 100% sure on this one
        return NSAccessibilityRaiseAction;

    // Not translated:
    //
    // Qt:
    //     static const QString &checkAction();
    //     static const QString &uncheckAction();
    //
    // Cocoa:
    //      NSAccessibilityConfirmAction;
    //      NSAccessibilityPickAction;
    //      NSAccessibilityCancelAction;
    //      NSAccessibilityDeleteAction;

    return 0;
}


/*
    Translates between a Mac action constant and a QAccessibleActionInterface action
    Returns an empty QString if there is no Qt predefined equivalent.
*/
QString translateAction(NSString *nsAction)
{
    if ([nsAction compare: NSAccessibilityPressAction] == NSOrderedSame)
        return QAccessibleActionInterface::pressAction();
    else if ([nsAction compare: NSAccessibilityIncrementAction] == NSOrderedSame)
        return QAccessibleActionInterface::increaseAction();
    else if ([nsAction compare: NSAccessibilityDecrementAction] == NSOrderedSame)
        return QAccessibleActionInterface::decreaseAction();
    else if ([nsAction compare: NSAccessibilityShowMenuAction] == NSOrderedSame)
        return QAccessibleActionInterface::showMenuAction();
    else if ([nsAction compare: NSAccessibilityRaiseAction] == NSOrderedSame)
        return QAccessibleActionInterface::setFocusAction();

    // See getTranslatedAction for not matched translations.

    return QString();
}

bool hasValueAttribute(QAccessibleInterface *interface)
{
    const QAccessible::Role qtrole = interface->role();
    if (qtrole == QAccessible::EditableText
            || interface->valueInterface()) {
        return true;
    }

    return false;
}

id getValueAttribute(QAccessibleInterface *interface)
{
    const QAccessible::Role qtrole = interface->role();
    if (qtrole == QAccessible::EditableText) {
        if (QAccessibleTextInterface *textInterface = interface->textInterface()) {
            // VoiceOver will read out the entire text string at once when returning
            // text as a value. For large text edits the size of the returned string
            // needs to be limited and text range attributes need to be used instead.
            // NSTextEdit returns the first sentence as the value, Do the same here:
            int begin = 0;
            int end = textInterface->characterCount();
            // ### call to textAfterOffset hangs. Booo!
            //if (textInterface->characterCount() > 0)
            //    textInterface->textAfterOffset(0, QAccessible2::SentenceBoundary, &begin, &end);

            QString text = textInterface->text(begin, end);
            //qDebug() << "text" << begin << end << text;
            return QCFString::toNSString(text);
        }
    }

    if (QAccessibleValueInterface *valueInterface = interface->valueInterface()) {
        return QCFString::toNSString(QString::number(valueInterface->currentValue().toDouble()));
    }

    return nil;
}

} // namespace QCocoaAccessible

#endif // QT_NO_COCOA_ACCESSIBILITY
