/////////////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) 2017     Statoil ASA
//
//  ResInsight is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  ResInsight 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 General Public License at <http://www.gnu.org/licenses/gpl.html>
//  for more details.
//
/////////////////////////////////////////////////////////////////////////////////

#include "cafQTreeViewStateSerializer.h"

#include <QTreeView>

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void setExpandedState( QStringList& nodes, QTreeView* view, QAbstractItemModel* model, const QModelIndex startIndex, QString path )
{
    path += QString::number( startIndex.row() ) + QString::number( startIndex.column() );
    for ( int i = 0; i < model->rowCount( startIndex ); ++i )
    {
        QModelIndex nextIndex = model->index( i, 0, startIndex );
        QString     nextPath  = path + QString::number( nextIndex.row() ) + QString::number( nextIndex.column() );
        if ( !nodes.contains( nextPath ) ) continue;

        setExpandedState( nodes, view, model, model->index( i, 0, startIndex ), path );
    }

    if ( nodes.contains( path ) )
    {
        view->setExpanded( startIndex.sibling( startIndex.row(), 0 ), true );
    }
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void storeExpandedState( QStringList&        nodes,
                         const QTreeView*    view,
                         QAbstractItemModel* model,
                         const QModelIndex   startIndex,
                         QString             path )
{
    path += QString::number( startIndex.row() ) + QString::number( startIndex.column() );
    for ( int i = 0; i < model->rowCount( startIndex ); ++i )
    {
        if ( !view->isExpanded( model->index( i, 0, startIndex ) ) ) continue;

        storeExpandedState( nodes, view, model, model->index( i, 0, startIndex ), path );
    }

    if ( view->isExpanded( startIndex ) )
    {
        nodes << path;
    }
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void caf::QTreeViewStateSerializer::applyTreeViewStateFromString( QTreeView* treeView, const QString& treeViewState )
{
    if ( treeView->model() )
    {
        treeView->collapseAll();

        QStringList nodes = treeViewState.split( ";" );

        QString path;
        setExpandedState( nodes, treeView, treeView->model(), QModelIndex(), path );
    }
}

//--------------------------------------------------------------------------------------------------
///
//--------------------------------------------------------------------------------------------------
void caf::QTreeViewStateSerializer::storeTreeViewStateToString( const QTreeView* treeView, QString& treeViewState )
{
    if ( treeView->model() )
    {
        QStringList nodes;
        QString     path;

        storeExpandedState( nodes, treeView, treeView->model(), QModelIndex(), path );

        treeViewState = nodes.join( ";" );
    }
}

//--------------------------------------------------------------------------------------------------
/// Find index based of an encode QString <row> <column>;<row> <column>;...;<row> <column>
/// Set the decoded index as current index in the QAbstractItemView
//--------------------------------------------------------------------------------------------------
QModelIndex caf::QTreeViewStateSerializer::getModelIndexFromString( QAbstractItemModel* model,
                                                                    const QString&      currentIndexString )
{
    QStringList modelIndexStringList = currentIndexString.split( ";" );

    QModelIndex mi;

    foreach ( QString modelIndexString, modelIndexStringList )
    {
        QStringList items = modelIndexString.split( " " );

        if ( items.size() != 2 ) continue;

        int row = items[0].toInt();
        int col = items[1].toInt();

        mi = model->index( row, col, mi );
    }

    return mi;
}

//--------------------------------------------------------------------------------------------------
/// Store path to model index in item view using follwoing encoding into a QString <row> <column>;<row>
/// <column>;...;<row> <column>
//--------------------------------------------------------------------------------------------------
void caf::QTreeViewStateSerializer::encodeStringFromModelIndex( const QModelIndex mi, QString& encodedModelIndex )
{
    if ( !mi.isValid() ) return;

    QModelIndex localModelIdx = mi;

    while ( localModelIdx.isValid() )
    {
        if ( encodedModelIndex.isEmpty() )
        {
            encodedModelIndex = QString( "%1 %2" ).arg( localModelIdx.row() ).arg( localModelIdx.column() ) +
                                encodedModelIndex;
        }
        else
        {
            encodedModelIndex = QString( "%1 %2;" ).arg( localModelIdx.row() ).arg( localModelIdx.column() ) +
                                encodedModelIndex;
        }
        localModelIdx = localModelIdx.parent();
    }
}