/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtGui module of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** GNU Lesser General Public License Usage

** Alternatively, this file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** In addition, as a special exception, Nokia gives you certain additional

** rights.  These rights are described in the Nokia Qt LGPL Exception

** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include "qtreewidget.h"

#ifndef QT_NO_TREEWIDGET

#include <qheaderview.h>

#include <qpainter.h>

#include <qitemdelegate.h>

#include <qstack.h>

#include <qdebug.h>

#include <private/qtreewidget_p.h>

#include <private/qwidgetitemdata_p.h>

#include <private/qtreewidgetitemiterator_p.h>

QT_BEGIN_NAMESPACE

// workaround for VC++ 6.0 linker bug (?)

typedef bool(*LessThan)(const QPair<QTreeWidgetItem*,int>&,const QPair<QTreeWidgetItem*,int>&);

class QTreeModelLessThan

{

public:

    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const

        { return *i1 < *i2; }

};

class QTreeModelGreaterThan

{

public:

    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const

        { return *i2 < *i1; }

};

/*

    \class QTreeModel

    \brief The QTreeModel class manages the items stored in a tree view.

    \ingroup model-view

*/

/*!

    \enum QTreeWidgetItem::ChildIndicatorPolicy

    \since 4.3

    \value ShowIndicator     The controls for expanding and collapsing will be shown for this item even if there are no children.

    \value DontShowIndicator   The controls for expanding and collapsing will never be shown even if there are children.  If the node is forced open the user will not be able to expand or collapse the item.

    \value DontShowIndicatorWhenChildless  The controls for expanding and collapsing will be shown if the item contains children.

*/

/*!

    \fn void QTreeWidgetItem::setDisabled(bool disabled)

    \since 4.3

    Disables the item if \a disabled is true; otherwise enables the item.

    \sa setFlags()

*/

/*!

    \fn bool QTreeWidgetItem::isDisabled() const

    \since 4.3

    Returns true if the item is disabled; otherwise returns false.

    \sa setFlags()

*/

/*!

  \internal

  Constructs a tree model with a \a parent object and the given

  number of \a columns.

*/

QTreeModel::QTreeModel(int columns, QTreeWidget *parent)

    : QAbstractItemModel(parent), rootItem(new QTreeWidgetItem),

      headerItem(new QTreeWidgetItem), skipPendingSort(false)

{

    rootItem->view = parent;

    rootItem->itemFlags = Qt::ItemIsDropEnabled;

    headerItem->view = parent;

    setColumnCount(columns);

}

/*!

  \internal

*/

QTreeModel::QTreeModel(QTreeModelPrivate &dd, QTreeWidget *parent)

    : QAbstractItemModel(dd, parent), rootItem(new QTreeWidgetItem),

      headerItem(new QTreeWidgetItem), skipPendingSort(false)

{

    rootItem->view = parent;

    rootItem->itemFlags = Qt::ItemIsDropEnabled;

    headerItem->view = parent;

}

/*!

  \internal

  Destroys this tree model.

*/

QTreeModel::~QTreeModel()

{

    clear();

    delete headerItem;

    rootItem->view = 0;

    delete rootItem;

}

/*!

  \internal

  Removes all items in the model.

*/

void QTreeModel::clear()

{

    SkipSorting skipSorting(this);

    for (int i = 0; i < rootItem->childCount(); ++i) {

        QTreeWidgetItem *item = rootItem->children.at(i);

        item->par = 0;

        item->view = 0;

        delete item;

    }

    rootItem->children.clear();

    sortPendingTimer.stop();

    reset();

}

/*!

  \internal

  Sets the number of \a columns in the tree model.

*/

void QTreeModel::setColumnCount(int columns)

{

    SkipSorting skipSorting(this);

    if (columns < 0)

        return;

    if (!headerItem) {

        headerItem = new QTreeWidgetItem();

        headerItem->view = view();

    }

    int count = columnCount();

    if (count == columns)

        return;

    if (columns < count) {

        beginRemoveColumns(QModelIndex(), columns, count - 1);

        headerItem->values.resize(columns);

        endRemoveColumns();

    } else {

        beginInsertColumns(QModelIndex(), count, columns - 1);

        headerItem->values.resize(columns);

        for (int i = count; i < columns; ++i) {// insert data without emitting the dataChanged signal

            headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));

            headerItem->d->display.append(QString::number(i + 1));

        }

        endInsertColumns();

    }

}

/*!

  \internal

  Returns the tree view item corresponding to the \a index given.

  \sa QModelIndex

*/

QTreeWidgetItem *QTreeModel::item(const QModelIndex &index) const

{

    if (!index.isValid())

        return 0;

    return static_cast<QTreeWidgetItem*>(index.internalPointer());

}

/*!

  \internal

  Returns the model index that refers to the

  tree view \a item and \a column.

*/

QModelIndex QTreeModel::index(const QTreeWidgetItem *item, int column) const

{

    executePendingSort();

    if (!item || (item == rootItem))

        return QModelIndex();

    const QTreeWidgetItem *par = item->parent();

    QTreeWidgetItem *itm = const_cast<QTreeWidgetItem*>(item);

    if (!par)

        par = rootItem;

    int row;

    int guess = item->d->rowGuess;

    if (guess >= 0

        && par->children.count() > guess

        && par->children.at(guess) == itm) {

        row = guess;

    } else {

        row = par->children.lastIndexOf(itm);

        itm->d->rowGuess = row;

    }

    return createIndex(row, column, itm);

}

/*!

  \internal

  \reimp

  Returns the model index with the given \a row,

  \a column and \a parent.

*/

QModelIndex QTreeModel::index(int row, int column, const QModelIndex &parent) const

{

    executePendingSort();

    int c = columnCount(parent);

    if (row < 0 || column < 0 || column >= c)

        return QModelIndex();

    QTreeWidgetItem *parentItem = parent.isValid() ? item(parent) : rootItem;

    if (parentItem && row < parentItem->childCount()) {

        QTreeWidgetItem *itm = parentItem->child(row);

        if (itm)

            return createIndex(row, column, itm);

        return QModelIndex();

    }

    return QModelIndex();

}

/*!

  \internal

  \reimp

  Returns the parent model index of the index given as

  the \a child.

*/

QModelIndex QTreeModel::parent(const QModelIndex &child) const

{

    SkipSorting skipSorting(this); //The reason we don't sort here is that this might be called from a valid QPersistentModelIndex

                                   //We don't want it to become suddenly invalid

    if (!child.isValid())

        return QModelIndex();

    QTreeWidgetItem *itm = static_cast<QTreeWidgetItem *>(child.internalPointer());

    if (!itm || itm == rootItem)

        return QModelIndex();

    QTreeWidgetItem *parent = itm->parent();

    return index(parent, 0);

}

/*!

  \internal

  \reimp

  Returns the number of rows in the \a parent model index.

*/

int QTreeModel::rowCount(const QModelIndex &parent) const

{

    if (!parent.isValid())

        return rootItem->childCount();

    QTreeWidgetItem *parentItem = item(parent);

    if (parentItem)

        return parentItem->childCount();

    return 0;

}

/*!

  \internal

  \reimp

  Returns the number of columns in the item referred to by

  the given \a index.

*/

int QTreeModel::columnCount(const QModelIndex &index) const

{

    Q_UNUSED(index);

    if (!headerItem)

        return 0;

    return headerItem->columnCount();

}

bool QTreeModel::hasChildren(const QModelIndex &parent) const

{

    if (!parent.isValid())

        return (rootItem->childCount() > 0);

    QTreeWidgetItem *itm = item(parent);

    if (!itm)

        return false;

    switch (itm->d->policy) {

    case QTreeWidgetItem::ShowIndicator:

        return true;

    case QTreeWidgetItem::DontShowIndicator:

        return false;

    case QTreeWidgetItem::DontShowIndicatorWhenChildless:

        return (itm->childCount() > 0);

    }

    return false;

}

/*!

  \internal

  \reimp

  Returns the data corresponding to the given model \a index

  and \a role.

*/

QVariant QTreeModel::data(const QModelIndex &index, int role) const

{

    if (!index.isValid())

        return QVariant();

    QTreeWidgetItem *itm = item(index);

    if (itm)

        return itm->data(index.column(), role);

    return QVariant();

}

/*!

  \internal

  \reimp

  Sets the data for the item specified by the \a index and \a role

  to that referred to by the \a value.

  Returns true if successful; otherwise returns false.

*/

bool QTreeModel::setData(const QModelIndex &index, const QVariant &value, int role)

{

    if (!index.isValid())

        return false;

    QTreeWidgetItem *itm = item(index);

    if (itm) {

        itm->setData(index.column(), role, value);

        return true;

    }

    return false;

}

QMap<int, QVariant> QTreeModel::itemData(const QModelIndex &index) const

{

    QMap<int, QVariant> roles;

    QTreeWidgetItem *itm = item(index);

    if (itm) {

        int column = index.column();

        if (column < itm->values.count()) {

            for (int i = 0; i < itm->values.at(column).count(); ++i) {

                roles.insert(itm->values.at(column).at(i).role,

                             itm->values.at(column).at(i).value);

            }

        }

        // the two special cases

        QVariant displayValue = itm->data(column, Qt::DisplayRole);

        if (displayValue.isValid())

            roles.insert(Qt::DisplayRole, displayValue);

        QVariant checkValue = itm->data(column, Qt::CheckStateRole);

        if (checkValue.isValid())

            roles.insert(Qt::CheckStateRole, checkValue);

    }

    return roles;

}

/*!

  \internal

  \reimp

*/

bool QTreeModel::insertRows(int row, int count, const QModelIndex &parent)

{

    SkipSorting skipSorting(this);

    if (count < 1 || row < 0 || row > rowCount(parent) || parent.column() > 0)

        return false;

    beginInsertRows(parent, row, row + count - 1);

    QTreeWidgetItem *par = item(parent);

    while (count > 0) {

        QTreeWidgetItem *item = new QTreeWidgetItem();

        item->view = view();

        item->par = par;

        if (par)

            par->children.insert(row++, item);

        else

            rootItem->children.insert(row++, item);

        --count;

    }

    endInsertRows();

    return true;

}

/*!

  \internal

  \reimp

*/

bool QTreeModel::insertColumns(int column, int count, const QModelIndex &parent)

{

    SkipSorting skipSorting(this);

    if (count < 1 || column < 0 || column > columnCount(parent) || parent.column() > 0 || !headerItem)

        return false;

    beginInsertColumns(parent, column, column + count - 1);

    int oldCount = columnCount(parent);

    column = qBound(0, column, oldCount);

    headerItem->values.resize(oldCount + count);

    for (int i = oldCount; i < oldCount + count; ++i) {

        headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));

        headerItem->d->display.append(QString::number(i + 1));

    }

    QStack<QTreeWidgetItem*> itemstack;

    itemstack.push(0);

    while (!itemstack.isEmpty()) {

        QTreeWidgetItem *par = itemstack.pop();

        QList<QTreeWidgetItem*> children = par ? par->children : rootItem->children;

        for (int row = 0; row < children.count(); ++row) {

            QTreeWidgetItem *child = children.at(row);

            if (child->children.count())

                itemstack.push(child);

            child->values.insert(column, count, QVector<QWidgetItemData>());

        }

    }

    endInsertColumns();

    return true;

}

/*!

  \internal

  \reimp

*/

bool QTreeModel::removeRows(int row, int count, const QModelIndex &parent) {

    if (count < 1 || row < 0 || (row + count) > rowCount(parent))

        return false;

    beginRemoveRows(parent, row, row + count - 1);

    bool blockSignal = signalsBlocked();

    blockSignals(true);

    QTreeWidgetItem *itm = item(parent);

    for (int i = row + count - 1; i >= row; --i) {

        QTreeWidgetItem *child = itm ? itm->takeChild(i) : rootItem->children.takeAt(i);

        Q_ASSERT(child);

        child->view = 0;

        delete child;

        child = 0;

    }

    blockSignals(blockSignal);

    endRemoveRows();

    return true;

}

/*!

  \internal

  \reimp

  Returns the header data corresponding to the given header \a section,

  \a orientation and data \a role.

*/

QVariant QTreeModel::headerData(int section, Qt::Orientation orientation, int role) const

{

    if (orientation != Qt::Horizontal)

        return QVariant();

    if (headerItem)

        return headerItem->data(section, role);

    if (role == Qt::DisplayRole)

        return QString::number(section + 1);

    return QVariant();

}

/*!