File indexing completed on 2025-01-19 04:52:04

 /*
     Copyright (c) 2009 Stephen Kelly <steveire@gmail.com>
 
     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Library General Public License as published by
     the Free Software Foundation; either version 2 of the License, or (at your
     option) any later version.
 
     This library is distributed in the hope that it will be useful, but WITHOUT
     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
     License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to the
     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301, USA.
 */
 
 #include "krecursivefilterproxymodel.h"
 
 #include <QMetaMethod>
 
 // Maintainability note:
 // This class invokes some Q_PRIVATE_SLOTs in QSortFilterProxyModel which are
 // private API and could be renamed or removed at any time.
 // If they are renamed, the invocations can be updated with an #if (QT_VERSION(...))
 // If they are removed, then layout{AboutToBe}Changed Q_SIGNALS should be used when the source model
 // gets new rows or has rowsremoved or moved. The Q_PRIVATE_SLOT invocation is an optimization
 // because layout{AboutToBe}Changed is expensive and causes the entire mapping of the tree in QSFPM
 // to be cleared, even if only a part of it is dirty.
 // Stephen Kelly, 30 April 2010.
 
 // All this is temporary anyway, the long term solution is support in QSFPM: https://codereview.qt-project.org/151000
 
 class KRecursiveFilterProxyModelPrivate
 {
     Q_DECLARE_PUBLIC(KRecursiveFilterProxyModel)
     KRecursiveFilterProxyModel *q_ptr;
 public:
     KRecursiveFilterProxyModelPrivate(KRecursiveFilterProxyModel *model)
         : q_ptr(model),
           completeInsert(false)
     {
         qRegisterMetaType<QModelIndex>("QModelIndex");
     }
 
     inline QMetaMethod findMethod(const char *signature) const
     {
         Q_Q(const KRecursiveFilterProxyModel);
         const int idx = q->metaObject()->indexOfMethod(signature);
         Q_ASSERT(idx != -1);
         return q->metaObject()->method(idx);
     }
 
     // Convenience methods for invoking the QSFPM Q_SLOTS. Those slots must be invoked with invokeMethod
     // because they are Q_PRIVATE_SLOTs
     inline void invokeDataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles = QVector<int>())
     {
         Q_Q(KRecursiveFilterProxyModel);
         // required for Qt 5.5 and upwards, see commit f96baeb75fc in qtbase
         static const QMetaMethod m = findMethod("_q_sourceDataChanged(QModelIndex,QModelIndex,QVector<int>)");
         bool success = m.invoke(q, Qt::DirectConnection,
                 Q_ARG(QModelIndex, topLeft),
                 Q_ARG(QModelIndex, bottomRight),
                 Q_ARG(QVector<int>, roles));
         Q_UNUSED(success);
         Q_ASSERT(success);
     }
 
     inline void invokeRowsInserted(const QModelIndex &source_parent, int start, int end)
     {
         Q_Q(KRecursiveFilterProxyModel);
         static const QMetaMethod m = findMethod("_q_sourceRowsInserted(QModelIndex,int,int)");
         bool success = m.invoke(q, Qt::DirectConnection,
                                 Q_ARG(QModelIndex, source_parent),
                                 Q_ARG(int, start),
                                 Q_ARG(int, end));
         Q_UNUSED(success);
         Q_ASSERT(success);
     }
 
     inline void invokeRowsAboutToBeInserted(const QModelIndex &source_parent, int start, int end)
     {
         Q_Q(KRecursiveFilterProxyModel);
         static const QMetaMethod m = findMethod("_q_sourceRowsAboutToBeInserted(QModelIndex,int,int)");
         bool success = m.invoke(q, Qt::DirectConnection,
                                 Q_ARG(QModelIndex, source_parent),
                                 Q_ARG(int, start),
                                 Q_ARG(int, end));
         Q_UNUSED(success);
         Q_ASSERT(success);
     }
 
     inline void invokeRowsRemoved(const QModelIndex &source_parent, int start, int end)
     {
         Q_Q(KRecursiveFilterProxyModel);
         static const QMetaMethod m = findMethod("_q_sourceRowsRemoved(QModelIndex,int,int)");
         bool success = m.invoke(q, Qt::DirectConnection,
                                 Q_ARG(QModelIndex, source_parent),
                                 Q_ARG(int, start),
                                 Q_ARG(int, end));
         Q_UNUSED(success);
         Q_ASSERT(success);
     }
 
     inline void invokeRowsAboutToBeRemoved(const QModelIndex &source_parent, int start, int end)
     {
         Q_Q(KRecursiveFilterProxyModel);
         static const QMetaMethod m = findMethod("_q_sourceRowsAboutToBeRemoved(QModelIndex,int,int)");
         bool success = m.invoke(q, Qt::DirectConnection,
                                 Q_ARG(QModelIndex, source_parent),
                                 Q_ARG(int, start),
                                 Q_ARG(int, end));
         Q_UNUSED(success);
         Q_ASSERT(success);
     }
 
     void sourceDataChanged(const QModelIndex &source_top_left, const QModelIndex &source_bottom_right, const QVector<int> &roles = QVector<int>());
     void sourceRowsAboutToBeInserted(const QModelIndex &source_parent, int start, int end);
     void sourceRowsInserted(const QModelIndex &source_parent, int start, int end);
     void sourceRowsAboutToBeRemoved(const QModelIndex &source_parent, int start, int end);
     void sourceRowsRemoved(const QModelIndex &source_parent, int start, int end);
 
     /**
     Force QSortFilterProxyModel to re-evaluate whether to hide or show index and its parents.
     */
     void refreshAscendantMapping(const QModelIndex &index);
 
     QModelIndex lastFilteredOutAscendant(const QModelIndex &index);
 
     bool completeInsert;
     QModelIndex lastHiddenAscendantForInsert;
 };
 
 void KRecursiveFilterProxyModelPrivate::sourceDataChanged(const QModelIndex &source_top_left, const QModelIndex &source_bottom_right, const QVector<int> &roles)
 {
     QModelIndex source_parent = source_top_left.parent();
     Q_ASSERT(source_bottom_right.parent() == source_parent); // don't know how to handle different parents in this code...
 
     // Tell the world.
     invokeDataChanged(source_top_left, source_bottom_right, roles);
 
     // We can't find out if the change really matters to us or not, for a lack of a dataAboutToBeChanged signal (or a cache).
     // TODO: add a set of roles that we care for, so we can at least ignore the rest.
 
     // Even if we knew the visibility was just toggled, we also can't find out what
     // was the last filtered out ascendant (on show, like sourceRowsAboutToBeInserted does)
     // or the last to-be-filtered-out ascendant (on hide, like sourceRowsRemoved does)
     // So we have to refresh all parents.
     QModelIndex sourceParent = source_parent;
     while (sourceParent.isValid()) {
         invokeDataChanged(sourceParent, sourceParent, roles);
         sourceParent = sourceParent.parent();
     }
 }
 
 QModelIndex KRecursiveFilterProxyModelPrivate::lastFilteredOutAscendant(const QModelIndex &idx)
 {
     Q_Q(KRecursiveFilterProxyModel);
     QModelIndex last = idx;
     QModelIndex index = idx.parent();
     while (index.isValid() && !q->filterAcceptsRow(index.row(), index.parent())) {
         last = index;
         index = index.parent();
     }
     return last;
 }
 
 void KRecursiveFilterProxyModelPrivate::sourceRowsAboutToBeInserted(const QModelIndex &source_parent, int start, int end)
 {
     Q_Q(KRecursiveFilterProxyModel);
 
     if (!source_parent.isValid() || q->filterAcceptsRow(source_parent.row(), source_parent.parent())) {
         // If the parent is already in the model (directly or indirectly), we can just pass on the signal.
         invokeRowsAboutToBeInserted(source_parent, start, end);
         completeInsert = true;
     } else {
         // OK, so parent is not in the model.
         // Maybe the grand parent neither.. Go up until the first one that is.
         lastHiddenAscendantForInsert = lastFilteredOutAscendant(source_parent);
     }
 }
 
 void KRecursiveFilterProxyModelPrivate::sourceRowsInserted(const QModelIndex &source_parent, int start, int end)
 {
     Q_Q(KRecursiveFilterProxyModel);
 
     if (completeInsert) {
         // If the parent is already in the model, we can just pass on the signal.
         completeInsert = false;
         invokeRowsInserted(source_parent, start, end);
         return;
     }
 
     bool requireRow = false;
     for (int row = start; row <= end; ++row) {
         if (q->filterAcceptsRow(row, source_parent)) {
             requireRow = true;
             break;
         }
     }
 
     if (!requireRow) {
         // The new rows doesn't have any descendants that match the filter. Filter them out.
         return;
     }
 
     // Make QSFPM realize that lastHiddenAscendantForInsert should be shown now
     invokeDataChanged(lastHiddenAscendantForInsert, lastHiddenAscendantForInsert);
 }
 
 void KRecursiveFilterProxyModelPrivate::sourceRowsAboutToBeRemoved(const QModelIndex &source_parent, int start, int end)
 {
     invokeRowsAboutToBeRemoved(source_parent, start, end);
 }
 
 void KRecursiveFilterProxyModelPrivate::sourceRowsRemoved(const QModelIndex &source_parent, int start, int end)
 {
     Q_Q(KRecursiveFilterProxyModel);
 
     invokeRowsRemoved(source_parent, start, end);
 
     // Find out if removing this visible row means that some ascendant
     // row can now be hidden.
     // We go up until we find a row that should still be visible
     // and then make QSFPM re-evaluate the last one we saw before that, to hide it.
 
     QModelIndex toHide;
     QModelIndex sourceAscendant = source_parent;
     while (sourceAscendant.isValid()) {
         if (q->filterAcceptsRow(sourceAscendant.row(), sourceAscendant.parent())) {
             break;
         }
         toHide = sourceAscendant;
         sourceAscendant = sourceAscendant.parent();
     }
     if (toHide.isValid()) {
         invokeDataChanged(toHide, toHide);
     }
 }
 
 KRecursiveFilterProxyModel::KRecursiveFilterProxyModel(QObject *parent)
     : QSortFilterProxyModel(parent), d_ptr(new KRecursiveFilterProxyModelPrivate(this))
 {
     setDynamicSortFilter(true);
 }
 
 KRecursiveFilterProxyModel::~KRecursiveFilterProxyModel()
 {
     delete d_ptr;
 }
 
 bool KRecursiveFilterProxyModel::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const
 {
     // TODO: Implement some caching so that if one match is found on the first pass, we can return early results
     // when the subtrees are checked by QSFPM.
     if (acceptRow(sourceRow, sourceParent)) {
         return true;
     }
 
     QModelIndex source_index = sourceModel()->index(sourceRow, 0, sourceParent);
     Q_ASSERT(source_index.isValid());
     bool accepted = false;
 
     const int numChildren = sourceModel()->rowCount(source_index);
     for (int row = 0, rows = numChildren; row < rows; ++row) {
         if (filterAcceptsRow(row, source_index)) {
             accepted = true;
             break;
         }
     }
 
     return accepted;
 }
 
 QModelIndexList KRecursiveFilterProxyModel::match(const QModelIndex &start, int role, const QVariant &value, int hits, Qt::MatchFlags flags) const
 {
     if (role < Qt::UserRole) {
         return QSortFilterProxyModel::match(start, role, value, hits, flags);
     }
 
     QModelIndexList list;
     if (!sourceModel())
         return list;
 
     QModelIndex proxyIndex;
     Q_FOREACH (const QModelIndex &idx, sourceModel()->match(mapToSource(start), role, value, hits, flags)) {
         proxyIndex = mapFromSource(idx);
         if (proxyIndex.isValid()) {
             list << proxyIndex;
         }
     }
 
     return list;
 }
 
 bool KRecursiveFilterProxyModel::acceptRow(int sourceRow, const QModelIndex &sourceParent) const
 {
     return QSortFilterProxyModel::filterAcceptsRow(sourceRow, sourceParent);
 }
 
 void KRecursiveFilterProxyModel::setSourceModel(QAbstractItemModel *model)
 {
     // Standard disconnect of the previous source model, if present
     if (sourceModel()) {
         disconnect(sourceModel(), SIGNAL(dataChanged(QModelIndex,QModelIndex,QVector<int>)),
                 this, SLOT(sourceDataChanged(QModelIndex,QModelIndex,QVector<int>)));
 
         disconnect(sourceModel(), SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
                 this, SLOT(sourceRowsAboutToBeInserted(QModelIndex,int,int)));
 
         disconnect(sourceModel(), SIGNAL(rowsInserted(QModelIndex,int,int)),
                 this, SLOT(sourceRowsInserted(QModelIndex,int,int)));
 
         disconnect(sourceModel(), SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
                 this, SLOT(sourceRowsAboutToBeRemoved(QModelIndex,int,int)));
 
         disconnect(sourceModel(), SIGNAL(rowsRemoved(QModelIndex,int,int)),
                 this, SLOT(sourceRowsRemoved(QModelIndex,int,int)));
     }
 
     QSortFilterProxyModel::setSourceModel(model);
 
     // Disconnect in the QSortFilterProxyModel. These methods will be invoked manually
     // in invokeDataChanged, invokeRowsInserted etc.
     //
     // The reason for that is that when the source model adds new rows for example, the new rows
     // May not match the filter, but maybe their child items do match.
     //
     // Source model before insert:
     //
     // - A
     // - B
     // - - C
     // - - D
     // - - - E
     // - - - F
     // - - - G
     // - H
     // - I
     //
     // If the A F and L (which doesn't exist in the source model yet) match the filter
     // the proxy will be:
     //
     // - A
     // - B
     // - - D
     // - - - F
     //
     // New rows are inserted in the source model below H:
     //
     // - A
     // - B
     // - - C
     // - - D
     // - - - E
     // - - - F
     // - - - G
     // - H
     // - - J
     // - - K
     // - - - L
     // - I
     //
     // As L matches the filter, it should be part of the KRecursiveFilterProxyModel.
     //
     // - A
     // - B
     // - - D
     // - - - F
     // - H
     // - - K
     // - - - L
     //
     // when the QSortFilterProxyModel gets a notification about new rows in H, it only checks
     // J and K to see if they match, ignoring L, and therefore not adding it to the proxy.
     // To work around that, we make sure that the QSFPM slot which handles that change in
     // the source model (_q_sourceRowsAboutToBeInserted) does not get called directly.
     // Instead we connect the sourceModel signal to our own slot in *this (sourceRowsAboutToBeInserted)
     // Inside that method, the entire new subtree is queried (J, K *and* L) to see if there is a match,
     // then the relevant Q_SLOTS in QSFPM are invoked.
     // In the example above, we need to tell the QSFPM that H should be queried again to see if
     // it matches the filter. It did not before, because L did not exist before. Now it does. That is
     // achieved by telling the QSFPM that the data changed for H, which causes it to requery this class
     // to see if H matches the filter (which it now does as L now exists).
     // That is done in sourceRowsInserted.
 
     if (!model) {
         return;
     }
 
     disconnect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex,QVector<int>)),
             this, SLOT(_q_sourceDataChanged(QModelIndex,QModelIndex,QVector<int>)));
 
     disconnect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
                this, SLOT(_q_sourceRowsAboutToBeInserted(QModelIndex,int,int)));
 
     disconnect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
                this, SLOT(_q_sourceRowsInserted(QModelIndex,int,int)));
 
     disconnect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
                this, SLOT(_q_sourceRowsAboutToBeRemoved(QModelIndex,int,int)));
 
     disconnect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
                this, SLOT(_q_sourceRowsRemoved(QModelIndex,int,int)));
 
     // Slots for manual invoking of QSortFilterProxyModel methods.
     connect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex,QVector<int>)),
             this, SLOT(sourceDataChanged(QModelIndex,QModelIndex,QVector<int>)));
 
     connect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
             this, SLOT(sourceRowsAboutToBeInserted(QModelIndex,int,int)));
 
     connect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
             this, SLOT(sourceRowsInserted(QModelIndex,int,int)));
 
     connect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
             this, SLOT(sourceRowsAboutToBeRemoved(QModelIndex,int,int)));
 
     connect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
             this, SLOT(sourceRowsRemoved(QModelIndex,int,int)));
 
 }
 
 #include "moc_krecursivefilterproxymodel.cpp"