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#include "qaccessiblequickitem.h"

#include <QtGui/qtextdocument.h>

#include "QtQuick/private/qquickitem_p.h"
#include "QtQuick/private/qquicktext_p.h"
#include "QtQuick/private/qquickaccessibleattached_p.h"
#include "QtQuick/qquicktextdocument.h"

QT_BEGIN_NAMESPACE

#ifndef QT_NO_ACCESSIBILITY

QAccessibleQuickItem::QAccessibleQuickItem(QQuickItem *item)
    : QQmlAccessible(item), m_doc(textDocument())
{
}

int QAccessibleQuickItem::childCount() const
{
    return childItems().count();
}

QRect QAccessibleQuickItem::rect() const
{
    const QRect r = itemScreenRect(item());

    if (!r.isValid()) {
        qWarning() << item()->metaObject()->className() << item()->property("accessibleText") << r;
    }
    return r;
}

QRect QAccessibleQuickItem::viewRect() const
{
    // ### no window in some cases.
    if (!item()->window()) {
        return QRect();
    }

    QQuickWindow *window = item()->window();
    QPoint screenPos = window->mapToGlobal(QPoint(0,0));
    return QRect(screenPos, window->size());
}


bool QAccessibleQuickItem::clipsChildren() const
{
    return static_cast<QQuickItem *>(item())->clip();
}

QAccessibleInterface *QAccessibleQuickItem::parent() const
{
    QQuickItem *parent = item()->parentItem();
    if (parent) {
        QQuickWindow *window = item()->window();
        // Jump out to the scene widget if the parent is the root item.
        // There are two root items, QQuickWindow::rootItem and
        // QQuickView::declarativeRoot. The former is the true root item,
        // but is not a part of the accessibility tree. Check if we hit
        // it here and return an interface for the scene instead.
        if (window && (parent == window->contentItem())) {
            return QAccessible::queryAccessibleInterface(window);
        } else {
            return QAccessible::queryAccessibleInterface(parent);
        }
    }
    return 0;
}

QAccessibleInterface *QAccessibleQuickItem::child(int index) const
{
    QList<QQuickItem *> children = childItems();

    if (index < 0 || index >= children.count())
        return 0;

    QQuickItem *child = children.at(index);
    if (!child) // FIXME can this happen?
        return 0;

    return QAccessible::queryAccessibleInterface(child);
}

int QAccessibleQuickItem::indexOfChild(const QAccessibleInterface *iface) const
{
    QList<QQuickItem*> kids = childItems();
    return kids.indexOf(static_cast<QQuickItem*>(iface->object()));
}

QList<QQuickItem *> QAccessibleQuickItem::childItems() const
{
    if (    role() == QAccessible::Button ||
            role() == QAccessible::CheckBox ||
            role() == QAccessible::RadioButton ||
            role() == QAccessible::SpinBox ||
            role() == QAccessible::EditableText ||
            role() == QAccessible::Slider ||
            role() == QAccessible::PageTab ||
            role() == QAccessible::ProgressBar)
        return QList<QQuickItem *>();

    QList<QQuickItem *> items;
    Q_FOREACH (QQuickItem *child, item()->childItems()) {
        QQuickItemPrivate *itemPrivate = QQuickItemPrivate::get(child);
        if (itemPrivate->isAccessible)
            items.append(child);
    }
    return items;
}

QAccessible::State QAccessibleQuickItem::state() const
{
    QAccessible::State state;

    if (item()->hasActiveFocus())
        state.focused = true;

    if (!item()->window() ||!item()->isVisible() || qFuzzyIsNull(item()->opacity()))
        state.invisible = true;

    QAccessible::Role r = role();
    switch (r) {
    case QAccessible::Button: {
        QVariant checkable = item()->property("checkable");
        if (!checkable.toBool())
            break;
        // fall through
    }
    case QAccessible::CheckBox:
    case QAccessible::RadioButton: {
        state.checkable = true;
        state.checked = item()->property("checked").toBool();
        break;
    }
    default:
        break;
    }

    return state;
}

QAccessible::Role QAccessibleQuickItem::role() const
{
    // Workaround for setAccessibleRole() not working for
    // Text items. Text items are special since they are defined
    // entirely from C++ (setting the role from QML works.)
    if (qobject_cast<QQuickText*>(const_cast<QQuickItem *>(item())))
        return QAccessible::StaticText;

    QVariant v = QQuickAccessibleAttached::property(item(), "role");
    bool ok;
    QAccessible::Role role = (QAccessible::Role)v.toInt(&ok);
    if (!ok)    // Not sure if this check is needed.
        role = QAccessible::Pane;
    return role;
}

bool QAccessibleQuickItem::isAccessible() const
{
    return item()->d_func()->isAccessible;
}

QString QAccessibleQuickItem::text(QAccessible::Text textType) const
{
    // handles generic behavior not specific to an item
    switch (textType) {
    case QAccessible::Name: {
        QVariant accessibleName = QQuickAccessibleAttached::property(object(), "name");
        if (!accessibleName.isNull())
            return accessibleName.toString();
        break;}
    case QAccessible::Description: {
        QVariant accessibleDecription = QQuickAccessibleAttached::property(object(), "description");
        if (!accessibleDecription.isNull())
            return accessibleDecription.toString();
        break;}
#ifdef Q_ACCESSIBLE_QUICK_ITEM_ENABLE_DEBUG_DESCRIPTION
    case QAccessible::DebugDescription: {
        QString debugString;
        debugString = QString::fromLatin1(object()->metaObject()->className()) + QLatin1Char(' ');
        debugString += isAccessible() ? QLatin1String("enabled") : QLatin1String("disabled");
        return debugString;
        break; }
#endif
    case QAccessible::Value:
    case QAccessible::Help:
    case QAccessible::Accelerator:
    default:
        break;
    }

    // the following block handles item-specific behavior
    if (role() == QAccessible::EditableText) {
        if (textType == QAccessible::Value) {
            if (QTextDocument *doc = textDocument()) {
                return doc->toPlainText();
            }
            QVariant text = object()->property("text");
            return text.toString();
        }
    }

    return QString();
}

void *QAccessibleQuickItem::interface_cast(QAccessible::InterfaceType t)
{
    QAccessible::Role r = role();
    if (t == QAccessible::ValueInterface &&
           (r == QAccessible::Slider ||
            r == QAccessible::SpinBox ||
            r == QAccessible::Dial ||
            r == QAccessible::ScrollBar))
       return static_cast<QAccessibleValueInterface*>(this);

    if (t == QAccessible::TextInterface &&
            (r == QAccessible::EditableText))
        return static_cast<QAccessibleTextInterface*>(this);

    return QQmlAccessible::interface_cast(t);
}

QVariant QAccessibleQuickItem::currentValue() const
{
    return item()->property("value");
}

void QAccessibleQuickItem::setCurrentValue(const QVariant &value)
{
    item()->setProperty("value", value);
}

QVariant QAccessibleQuickItem::maximumValue() const
{
    return item()->property("maximumValue");
}

QVariant QAccessibleQuickItem::minimumValue() const
{
    return item()->property("minimumValue");
}

QVariant QAccessibleQuickItem::minimumStepSize() const
{
    return item()->property("stepSize");
}

/*!
  \internal
  Shared between QAccessibleQuickItem and QAccessibleQuickView
*/
QRect itemScreenRect(QQuickItem *item)
{
    // ### no window in some cases.
    // ### Should we really check for 0 opacity?
    if (!item->window() ||!item->isVisible() || qFuzzyIsNull(item->opacity())) {
        return QRect();
    }

    QSize itemSize((int)item->width(), (int)item->height());
    // ### If the bounding rect fails, we first try the implicit size, then we go for the
    // parent size. WE MIGHT HAVE TO REVISIT THESE FALLBACKS.
    if (itemSize.isEmpty()) {
        itemSize = QSize((int)item->implicitWidth(), (int)item->implicitHeight());
        if (itemSize.isEmpty() && item->parentItem())
            // ### Seems that the above fallback is not enough, fallback to use the parent size...
            itemSize = QSize((int)item->parentItem()->width(), (int)item->parentItem()->height());
    }

    QPointF scenePoint = item->mapToScene(QPointF(0, 0));
    QPoint screenPos = item->window()->mapToGlobal(scenePoint.toPoint());
    return QRect(screenPos, itemSize);
}

QTextDocument *QAccessibleQuickItem::textDocument() const
{
    QVariant docVariant = item()->property("textDocument");
    if (docVariant.canConvert<QQuickTextDocument*>()) {
        QQuickTextDocument *qqdoc = docVariant.value<QQuickTextDocument*>();
        return qqdoc->textDocument();
    }
    return 0;
}

int QAccessibleQuickItem::characterCount() const
{
    if (m_doc) {
        QTextCursor cursor = QTextCursor(m_doc);
        cursor.movePosition(QTextCursor::End);
        return cursor.position();
    }
    return text(QAccessible::Value).size();
}

int QAccessibleQuickItem::cursorPosition() const
{
    QVariant pos = item()->property("cursorPosition");
    return pos.toInt();
}

void QAccessibleQuickItem::setCursorPosition(int position)
{
    item()->setProperty("cursorPosition", position);
}

QString QAccessibleQuickItem::text(int startOffset, int endOffset) const
{
    if (m_doc) {
        QTextCursor cursor = QTextCursor(m_doc);
        cursor.setPosition(startOffset);
        cursor.setPosition(endOffset, QTextCursor::KeepAnchor);
        return cursor.selectedText();
    }
    return text(QAccessible::Value).mid(startOffset, endOffset - startOffset);
}

QString QAccessibleQuickItem::textBeforeOffset(int offset, QAccessible::TextBoundaryType boundaryType,
                                 int *startOffset, int *endOffset) const
{
    Q_ASSERT(startOffset);
    Q_ASSERT(endOffset);

    if (m_doc) {
        QTextCursor cursor = QTextCursor(m_doc);
        cursor.setPosition(offset);
        QPair<int, int> boundaries = QAccessible::qAccessibleTextBoundaryHelper(cursor, boundaryType);
        cursor.setPosition(boundaries.first - 1);
        boundaries = QAccessible::qAccessibleTextBoundaryHelper(cursor, boundaryType);

        *startOffset = boundaries.first;
        *endOffset = boundaries.second;

        return text(boundaries.first, boundaries.second);
    } else {
        return QAccessibleTextInterface::textBeforeOffset(offset, boundaryType, startOffset, endOffset);
    }
}

QString QAccessibleQuickItem::textAfterOffset(int offset, QAccessible::TextBoundaryType boundaryType,
                                int *startOffset, int *endOffset) const
{
    Q_ASSERT(startOffset);
    Q_ASSERT(endOffset);

    if (m_doc) {
        QTextCursor cursor = QTextCursor(m_doc);
        cursor.setPosition(offset);
        QPair<int, int> boundaries = QAccessible::qAccessibleTextBoundaryHelper(cursor, boundaryType);
        cursor.setPosition(boundaries.second);
        boundaries = QAccessible::qAccessibleTextBoundaryHelper(cursor, boundaryType);

        *startOffset = boundaries.first;
        *endOffset = boundaries.second;

        return text(boundaries.first, boundaries.second);
    } else {
        return QAccessibleTextInterface::textAfterOffset(offset, boundaryType, startOffset, endOffset);
    }
}

QString QAccessibleQuickItem::textAtOffset(int offset, QAccessible::TextBoundaryType boundaryType,
                             int *startOffset, int *endOffset) const
{
    Q_ASSERT(startOffset);
    Q_ASSERT(endOffset);

    if (m_doc) {
        QTextCursor cursor = QTextCursor(m_doc);
        cursor.setPosition(offset);
        QPair<int, int> boundaries = QAccessible::qAccessibleTextBoundaryHelper(cursor, boundaryType);

        *startOffset = boundaries.first;
        *endOffset = boundaries.second;
        return text(boundaries.first, boundaries.second);
    } else {
        return QAccessibleTextInterface::textAtOffset(offset, boundaryType, startOffset, endOffset);
    }
}

void QAccessibleQuickItem::selection(int selectionIndex, int *startOffset, int *endOffset) const
{
    if (selectionIndex == 0) {
        *startOffset = item()->property("selectionStart").toInt();
        *endOffset = item()->property("selectionEnd").toInt();
    } else {
        *startOffset = 0;
        *endOffset = 0;
    }
}

int QAccessibleQuickItem::selectionCount() const
{
    if (item()->property("selectionStart").toInt() != item()->property("selectionEnd").toInt())
        return 1;
    return 0;
}

void QAccessibleQuickItem::addSelection(int /* startOffset */, int /* endOffset */)
{

}
void QAccessibleQuickItem::removeSelection(int /* selectionIndex */)
{

}
void QAccessibleQuickItem::setSelection(int /* selectionIndex */, int /* startOffset */, int /* endOffset */)
{

}


#endif // QT_NO_ACCESSIBILITY

QT_END_NAMESPACE
