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** Alternatively, this file may be used under the terms of the GNU
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#include <QtQuickTemplates2/private/qquickheaderview_p_p.h>
#include <algorithm>

/*!
    \qmltype HorizontalHeaderView
    \inqmlmodule QtQuick.Controls
    \ingroup qtquickcontrols2-containers
    \inherits TableView
    \brief Provides a horizontal header view to accompany a \l TableView.

    A HorizontalHeaderView provides labeling of the columns of a \l TableView.
    To add a horizontal header to a TableView, bind the
    \l {HorizontalHeaderView::syncView} {syncView} property to the TableView:

    \snippet qtquickcontrols2-headerview-simple.qml horizontal

    The header displays data from the {syncView}'s model by default, but can
    also have its own model. If the model is a QAbstractTableModel, then
    the header will display the model's horizontal headerData(); otherwise,
    the model's data().
*/

/*!
    \qmltype VerticalHeaderView
    \inqmlmodule QtQuick.Controls
    \ingroup qtquickcontrols2-containers
    \inherits TableView
    \brief Provides a vertical header view to accompany a \l TableView.

    A VerticalHeaderView provides labeling of the rows of a \l TableView.
    To add a vertical header to a TableView, bind the
    \l {VerticalHeaderView::syncView} {syncView} property to the TableView:

    \snippet qtquickcontrols2-headerview-simple.qml vertical

    The header displays data from the {syncView}'s model by default, but can
    also have its own model. If the model is a QAbstractTableModel, then
    the header will display the model's vertical headerData(); otherwise,
    the model's data().
*/

/*!
    \qmlproperty TableView QtQuick::HorizontalHeaderView::syncView

    This property holds the TableView to synchronize with.

    Once this property is bound to another TableView, both header and table
    will synchronize with regard to column widths, column spacing, and flicking
    horizontally.

    If the \l model is not explicitly set, then the header will use the syncView's
    model to label the columns.

    \sa model TableView
*/

/*!
    \qmlproperty TableView QtQuick::VerticalHeaderView::syncView

    This property holds the TableView to synchronize with.

    Once this property is bound to another TableView, both header and table
    will synchronize with regard to row heights, row spacing, and flicking
    vertically.

    If the \l model is not explicitly set, then the header will use the syncView's
    model to label the rows.

    \sa model TableView
*/

/*!
    \qmlproperty QVariant QtQuick::HorizontalHeaderView::model

    This property holds the model providing data for the horizontal header view.

    When model is not explicitly set, the header will use the syncView's
    model once syncView is set.

    If model is a QAbstractTableModel, its horizontal headerData() will
    be accessed.

    If model is a QAbstractItemModel other than QAbstractTableModel, model's data()
    will be accessed.

    Otherwise, the behavior is same as setting TableView::model.

    \sa TableView {TableView::model} {model} QAbstractTableModel
*/

/*!
    \qmlproperty QVariant QtQuick::VerticalHeaderView::model

    This property holds the model providing data for the vertical header view.

    When model is not explicitly set, it will be synchronized with syncView's model
    once syncView is set.

    If model is a QAbstractTableModel, its vertical headerData() will
    be accessed.

    If model is a QAbstractItemModel other than QAbstractTableModel, model's data()
    will be accessed.

    Otherwise, the behavior is same as setting TableView::model.

    \sa TableView {TableView::model} {model} QAbstractTableModel
*/

/*!
    \qmlproperty QString QtQuick::HorizontalHeaderView::textRole

    This property holds the model role used to display text in each header cell.

    When the model has multiple roles, textRole can be set to determine which
    role should be displayed.

    If model is a QAbstractItemModel then it will default to "display"; otherwise
    it is empty.

    \sa QAbstractItemModel::roleNames()
*/

/*!
    \qmlproperty QString QtQuick::VerticalHeaderView::textRole

    This property holds the model role used to display text in each header cell.

    When the model has multiple roles, textRole can be set to determine which
    role should be displayed.

    If model is a QAbstractItemModel then it will default to "display"; otherwise
    it is empty.

    \sa QAbstractItemModel::roleNames()
*/

QT_BEGIN_NAMESPACE

QQuickHeaderViewBasePrivate::QQuickHeaderViewBasePrivate()
    : QQuickTableViewPrivate()
{
}

QQuickHeaderViewBasePrivate::~QQuickHeaderViewBasePrivate()
{
}

const QPointer<QQuickItem> QQuickHeaderViewBasePrivate::delegateItemAt(int row, int col) const
{
    return loadedTableItem(QPoint(col, row))->item;
}

QVariant QQuickHeaderViewBasePrivate::modelImpl() const
{
    if (auto model = m_headerDataProxyModel.sourceModel())
        return QVariant::fromValue(model.data());
    if (auto model = m_transposeProxyModel.sourceModel())
        return QVariant::fromValue(model);
    return QQuickTableViewPrivate::modelImpl();
}

template <typename P, typename M>
inline bool proxyModelSetter(QQuickHeaderViewBase *const q, P &proxyModel, M *model)
{
    if (model) {
        if (model == proxyModel.sourceModel())
            return true;
        proxyModel.setSourceModel(model);
        const auto &modelVariant = QVariant::fromValue(std::addressof(proxyModel));
        bool isProxyModelChanged = (modelVariant != QQuickTableViewPrivate::get(q)->QQuickTableViewPrivate::modelImpl());
        QQuickTableViewPrivate::get(q)->QQuickTableViewPrivate::setModelImpl(modelVariant);
        //Necessary, since TableView's assigned model not changed, but proxy's source changed
        if (!isProxyModelChanged)
            emit q->modelChanged();
        return true;
    }
    proxyModel.setSourceModel(nullptr);
    return false;
}

void QQuickHeaderViewBasePrivate::setModelImpl(const QVariant &newModel)
{
    Q_Q(QQuickHeaderViewBase);
    m_modelExplicitlySetByUser = true;
    // Case 1: newModel is QAbstractTableModel
    if (proxyModelSetter(q, m_headerDataProxyModel, newModel.value<QAbstractTableModel *>()))
        return;
    // Case 2: newModel is QAbstractItemModel but not QAbstractTableModel
    if (orientation() == Qt::Horizontal
        && proxyModelSetter(q, m_transposeProxyModel, newModel.value<QAbstractItemModel *>()))
        return;

    QQuickTableViewPrivate::setModelImpl(newModel);
}

void QQuickHeaderViewBasePrivate::syncModel()
{
    Q_Q(QQuickHeaderViewBase);

    if (assignedSyncView && !m_modelExplicitlySetByUser) {
        auto newModel = assignedSyncView->model();
        if (auto m = newModel.value<QAbstractItemModel *>())
            proxyModelSetter(q, m_headerDataProxyModel, m);
    }

    QQuickTableViewPrivate::syncModel();

    isTransposed = false;
    const auto aim = model->abstractItemModel();
    if (orientation() == Qt::Horizontal) {
        // For models that are just a list or a number, and especially not a
        // table, we transpose the view when the orientation is horizontal.
        // The model (list) will then be laid out horizontally rather than
        // vertically, which is the otherwise the default.
        isTransposed = !aim || aim->columnCount() == 1;
    }
    if (m_textRole.isEmpty() && aim)
        m_textRole = QLatin1String("display");
}

void QQuickHeaderViewBasePrivate::syncSyncView()
{
    Q_Q(QQuickHeaderViewBase);
    if (assignedSyncDirection != orientation()) {
        qmlWarning(q_func()) << "Setting syncDirection other than Qt::"
                             << QVariant::fromValue(orientation()).toString()
                             << " is invalid.";
        assignedSyncDirection = orientation();
    }
    if (assignedSyncView) {
        QBoolBlocker fixupGuard(inUpdateContentSize, true);
        if (orientation() == Qt::Horizontal) {
            q->setLeftMargin(assignedSyncView->leftMargin());
            q->setRightMargin(assignedSyncView->rightMargin());
        } else {
            q->setTopMargin(assignedSyncView->topMargin());
            q->setBottomMargin(assignedSyncView->bottomMargin());
        }
    }
    QQuickTableViewPrivate::syncSyncView();
}

QQuickHeaderViewBase::QQuickHeaderViewBase(Qt::Orientation orient, QQuickItem *parent)
    : QQuickTableView(*(new QQuickHeaderViewBasePrivate), parent)
{
    d_func()->setOrientation(orient);
    setSyncDirection(orient);
}

QQuickHeaderViewBase::QQuickHeaderViewBase(QQuickHeaderViewBasePrivate &dd, QQuickItem *parent)
    : QQuickTableView(dd, parent)
{
}

QQuickHeaderViewBase::~QQuickHeaderViewBase()
{
}

QString QQuickHeaderViewBase::textRole() const
{
    Q_D(const QQuickHeaderViewBase);
    return d->m_textRole;
}

void QQuickHeaderViewBase::setTextRole(const QString &role)
{
    Q_D(QQuickHeaderViewBase);
    if (d->m_textRole == role)
        return;

    d->m_textRole = role;
    emit textRoleChanged();
}

Qt::Orientation QQuickHeaderViewBasePrivate::orientation() const
{
    return m_headerDataProxyModel.orientation();
}

void QQuickHeaderViewBasePrivate::setOrientation(Qt::Orientation orientation)
{
    if (QQuickHeaderViewBasePrivate::orientation() == orientation)
        return;
    m_headerDataProxyModel.setOrientation(orientation);
}

QQuickVerticalHeaderView::QQuickVerticalHeaderView(QQuickVerticalHeaderViewPrivate &dd, QQuickItem *parent)
    : QQuickHeaderViewBase(dd, parent)
{
}

/*! \internal
    \class QHeaderDataProxyModel
    \brief
    QHeaderDataProxyModel is a proxy AbstractItemModel type that maps
    source model's headerData() to correspondent data()
 */
QHeaderDataProxyModel::QHeaderDataProxyModel(QObject *parent)
    : QAbstractItemModel(parent)
{
}

QHeaderDataProxyModel::~QHeaderDataProxyModel() = default;

void QHeaderDataProxyModel::setSourceModel(QAbstractItemModel *newSourceModel)
{
    if (m_model == newSourceModel)
        return;
    beginResetModel();
    disconnectFromModel();
    m_model = newSourceModel;
    connectToModel();
    endResetModel();
}

QModelIndex QHeaderDataProxyModel::index(int row, int column, const QModelIndex &parent) const
{
    return hasIndex(row, column, parent) ? createIndex(row, column) : QModelIndex();
}

QModelIndex QHeaderDataProxyModel::parent(const QModelIndex &child) const
{
    Q_UNUSED(child);
    return QModelIndex();
}

QModelIndex QHeaderDataProxyModel::sibling(int row, int column, const QModelIndex &idx) const
{
    return index(row, column, idx);
}

int QHeaderDataProxyModel::rowCount(const QModelIndex &parent) const
{
    return m_model.isNull() ? -1 : (m_orientation == Qt::Horizontal ? 1 : m_model->rowCount(parent));
}

int QHeaderDataProxyModel::columnCount(const QModelIndex &parent) const
{
    return m_model.isNull() ? -1 : (m_orientation == Qt::Vertical ? 1 : m_model->columnCount(parent));
}

QVariant QHeaderDataProxyModel::data(const QModelIndex &index, int role) const
{
    if (m_model.isNull())
        return QVariant();
    if (!hasIndex(index.row(), index.column()))
        return QModelIndex();
    auto section = m_orientation == Qt::Vertical ? index.row() : index.column();
    return m_model->headerData(section, m_orientation, role);
}

bool QHeaderDataProxyModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (!hasIndex(index.row(), index.column()))
        return false;
    auto section = m_orientation == Qt::Vertical ? index.row() : index.column();
    auto ret = m_model->setHeaderData(section, m_orientation, value, role);
    emit dataChanged(index, index, { role });
    return ret;
}

bool QHeaderDataProxyModel::hasChildren(const QModelIndex &parent) const
{
    Q_UNUSED(parent);
    return false;
}

QVariant QHeaderDataProxyModel::variantValue() const
{
    return QVariant::fromValue(static_cast<QObject *>(const_cast<QHeaderDataProxyModel *>(this)));
}

void QHeaderDataProxyModel::setOrientation(Qt::Orientation o)
{
    if (o == m_orientation)
        return;
    beginResetModel();
    m_orientation = o;
    endResetModel();
}

Qt::Orientation QHeaderDataProxyModel::orientation() const
{
    return m_orientation;
}

QPointer<QAbstractItemModel> QHeaderDataProxyModel::sourceModel() const
{
    return m_model;
}

void QHeaderDataProxyModel::connectToModel()
{
    if (m_model.isNull())
        return;
    connect(m_model, &QAbstractItemModel::headerDataChanged,
        [this](Qt::Orientation orient, int first, int last) {
            if (orient != orientation())
                return;
            if (orient == Qt::Horizontal) {
                emit dataChanged(createIndex(0, first), createIndex(0, last));
            } else {
                emit dataChanged(createIndex(first, 0), createIndex(last, 0));
            }
        });
    connect(m_model, &QAbstractItemModel::modelAboutToBeReset,
        this, &QHeaderDataProxyModel::modelAboutToBeReset, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::modelReset,
        this, &QHeaderDataProxyModel::modelReset, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsAboutToBeMoved,
        this, &QHeaderDataProxyModel::rowsAboutToBeMoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsMoved,
        this, &QHeaderDataProxyModel::rowsMoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsAboutToBeInserted,
        this, &QHeaderDataProxyModel::rowsAboutToBeInserted, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsInserted,
        this, &QHeaderDataProxyModel::rowsInserted, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsAboutToBeRemoved,
        this, &QHeaderDataProxyModel::rowsAboutToBeRemoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::rowsRemoved,
        this, &QHeaderDataProxyModel::rowsRemoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsAboutToBeMoved,
        this, &QHeaderDataProxyModel::columnsAboutToBeMoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsMoved,
        this, &QHeaderDataProxyModel::columnsMoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsAboutToBeInserted,
        this, &QHeaderDataProxyModel::columnsAboutToBeInserted, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsInserted,
        this, &QHeaderDataProxyModel::columnsInserted, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsAboutToBeRemoved,
        this, &QHeaderDataProxyModel::columnsAboutToBeRemoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::columnsRemoved,
        this, &QHeaderDataProxyModel::columnsRemoved, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::layoutAboutToBeChanged,
        this, &QHeaderDataProxyModel::layoutAboutToBeChanged, Qt::UniqueConnection);
    connect(m_model, &QAbstractItemModel::layoutChanged,
        this, &QHeaderDataProxyModel::layoutChanged, Qt::UniqueConnection);
}

void QHeaderDataProxyModel::disconnectFromModel()
{
    if (m_model.isNull())
        return;
    m_model->disconnect(this);
}

QQuickHorizontalHeaderView::QQuickHorizontalHeaderView(QQuickItem *parent)
    : QQuickHeaderViewBase(Qt::Horizontal, parent)
{
    setFlickableDirection(FlickableDirection::HorizontalFlick);
}

QQuickHorizontalHeaderView::~QQuickHorizontalHeaderView()
{
}

QQuickVerticalHeaderView::QQuickVerticalHeaderView(QQuickItem *parent)
    : QQuickHeaderViewBase(Qt::Vertical, parent)
{
    setFlickableDirection(FlickableDirection::VerticalFlick);
}

QQuickVerticalHeaderView::~QQuickVerticalHeaderView()
{
}

QQuickHorizontalHeaderViewPrivate::QQuickHorizontalHeaderViewPrivate() = default;

QQuickHorizontalHeaderViewPrivate::~QQuickHorizontalHeaderViewPrivate() = default;

QQuickVerticalHeaderViewPrivate::QQuickVerticalHeaderViewPrivate() = default;

QQuickVerticalHeaderViewPrivate::~QQuickVerticalHeaderViewPrivate() = default;

QT_END_NAMESPACE