/****************************************************************************
**
** Copyright (C) 2009 Stephen Kelly <steveire@gmail.com>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the test suite of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL-EXCEPT$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
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** $QT_END_LICENSE$
**
****************************************************************************/

#include "dynamictreemodel.h"

#include <QtCore/QHash>
#include <QtCore/QList>
#include <QtCore/QTimer>
#include <QtCore/QDebug>


DynamicTreeModel::DynamicTreeModel(QObject *parent)
  : QAbstractItemModel(parent),
    nextId(1)
{
}

QModelIndex DynamicTreeModel::index(int row, int column, const QModelIndex &parent) const
{
//   if (column != 0)
//     return QModelIndex();


  if ( column < 0 || row < 0 )
    return QModelIndex();

  QList<QList<qint64> > childIdColumns = m_childItems.value(parent.internalId());

  const qint64 grandParent = findParentId(parent.internalId());
  if (grandParent >= 0) {
    QList<QList<qint64> > parentTable = m_childItems.value(grandParent);
    if (parent.column() >= parentTable.size())
        qFatal("%s: parent.column() must be less than parentTable.size()", Q_FUNC_INFO);
    QList<qint64> parentSiblings = parentTable.at(parent.column());
    if (parent.row() >= parentSiblings.size())
        qFatal("%s: parent.row() must be less than parentSiblings.size()", Q_FUNC_INFO);
  }

  if (childIdColumns.size() == 0)
    return QModelIndex();

  if (column >= childIdColumns.size())
    return QModelIndex();

  QList<qint64> rowIds = childIdColumns.at(column);

  if ( row >= rowIds.size())
    return QModelIndex();

  qint64 id = rowIds.at(row);

  return createIndex(row, column, reinterpret_cast<void *>(id));

}

qint64 DynamicTreeModel::findParentId(qint64 searchId) const
{
  if (searchId <= 0)
    return -1;

  QHashIterator<qint64, QList<QList<qint64> > > i(m_childItems);
  while (i.hasNext())
  {
    i.next();
    QListIterator<QList<qint64> > j(i.value());
    while (j.hasNext())
    {
      QList<qint64> l = j.next();
      if (l.contains(searchId))
      {
        return i.key();
      }
    }
  }
  return -1;
}

QModelIndex DynamicTreeModel::parent(const QModelIndex &index) const
{
  if (!index.isValid())
    return QModelIndex();

  qint64 searchId = index.internalId();
  qint64 parentId = findParentId(searchId);
  // Will never happen for valid index, but what the hey...
  if (parentId <= 0)
    return QModelIndex();

  qint64 grandParentId = findParentId(parentId);
  if (grandParentId < 0)
    grandParentId = 0;

  int column = 0;
  QList<qint64> childList = m_childItems.value(grandParentId).at(column);

  int row = childList.indexOf(parentId);

  return createIndex(row, column, reinterpret_cast<void *>(parentId));

}

int DynamicTreeModel::rowCount(const QModelIndex &index ) const
{
  QList<QList<qint64> > cols = m_childItems.value(index.internalId());

  if (cols.size() == 0 )
    return 0;

  if (index.column() > 0)
    return 0;

  return cols.at(0).size();
}

int DynamicTreeModel::columnCount(const QModelIndex &index ) const
{
//   Q_UNUSED(index);
  return m_childItems.value(index.internalId()).size();
}

QVariant DynamicTreeModel::data(const QModelIndex &index, int role) const
{
  if (!index.isValid())
    return QVariant();

  if (Qt::DisplayRole == role)
  {
    return m_items.value(index.internalId());
  }
  return QVariant();
}

void DynamicTreeModel::clear()
{
  beginResetModel();
  m_items.clear();
  m_childItems.clear();
  nextId = 1;
  endResetModel();
}


ModelChangeCommand::ModelChangeCommand( DynamicTreeModel *model, QObject *parent )
    : QObject(parent), m_model(model), m_numCols(1), m_startRow(-1), m_endRow(-1)
{

}

QModelIndex ModelChangeCommand::findIndex(QList<int> rows)
{
  const int col = 0;
  QModelIndex parent = QModelIndex();
  QListIterator<int> i(rows);
  while (i.hasNext())
  {
    parent = m_model->index(i.next(), col, parent);
    if (!parent.isValid())
        qFatal("%s: parent must be valid", Q_FUNC_INFO);
  }
  return parent;
}

ModelInsertCommand::ModelInsertCommand(DynamicTreeModel *model, QObject *parent )
    : ModelChangeCommand(model, parent)
{

}

void ModelInsertCommand::doCommand()
{
  QModelIndex parent = findIndex(m_rowNumbers);
  m_model->beginInsertRows(parent, m_startRow, m_endRow);
  qint64 parentId = parent.internalId();
  for (int row = m_startRow; row <= m_endRow; row++)
  {
    for(int col = 0; col < m_numCols; col++ )
    {
      if (m_model->m_childItems[parentId].size() <= col)
      {
        m_model->m_childItems[parentId].append(QList<qint64>());
      }
//       QString name = QUuid::createUuid().toString();
      qint64 id = m_model->newId();
      QString name = QString::number(id);

      m_model->m_items.insert(id, name);
      m_model->m_childItems[parentId][col].insert(row, id);

    }
  }
  m_model->endInsertRows();
}


ModelMoveCommand::ModelMoveCommand(DynamicTreeModel *model, QObject *parent)
  : ModelChangeCommand(model, parent)
{

}
bool ModelMoveCommand::emitPreSignal(const QModelIndex &srcParent, int srcStart, int srcEnd, const QModelIndex &destParent, int destRow)
{
  return m_model->beginMoveRows(srcParent, srcStart, srcEnd, destParent, destRow);
}

void ModelMoveCommand::doCommand()
{
    QModelIndex srcParent = findIndex(m_rowNumbers);
    QModelIndex destParent = findIndex(m_destRowNumbers);

    if (!emitPreSignal(srcParent, m_startRow, m_endRow, destParent, m_destRow))
    {
        return;
    }

    for (int column = 0; column < m_numCols; ++column)
    {
        QList<qint64> l = m_model->m_childItems.value(srcParent.internalId())[column].mid(m_startRow, m_endRow - m_startRow + 1 );

        for (int i = m_startRow; i <= m_endRow ; i++)
        {
            m_model->m_childItems[srcParent.internalId()][column].removeAt(m_startRow);
        }
        int d;
        if (m_destRow < m_startRow)
            d = m_destRow;
        else
        {
            if (srcParent == destParent)
                d = m_destRow - (m_endRow - m_startRow + 1);
            else
                d = m_destRow - (m_endRow - m_startRow) + 1;
        }

        foreach(const qint64 id, l)
        {
            m_model->m_childItems[destParent.internalId()][column].insert(d++, id);
        }
    }

    emitPostSignal();
}

void ModelMoveCommand::emitPostSignal()
{
    m_model->endMoveRows();
}

ModelResetCommand::ModelResetCommand(DynamicTreeModel* model, QObject* parent)
  : ModelMoveCommand(model, parent)
{

}

ModelResetCommand::~ModelResetCommand()
{

}

bool ModelResetCommand::emitPreSignal(const QModelIndex &srcParent, int srcStart, int srcEnd, const QModelIndex &destParent, int destRow)
{
    Q_UNUSED(srcParent);
    Q_UNUSED(srcStart);
    Q_UNUSED(srcEnd);
    Q_UNUSED(destParent);
    Q_UNUSED(destRow);

    return true;
}

void ModelResetCommand::emitPostSignal()
{
    m_model->beginResetModel();
    m_model->endResetModel();
}

ModelResetCommandFixed::ModelResetCommandFixed(DynamicTreeModel* model, QObject* parent)
  : ModelMoveCommand(model, parent)
{

}

ModelResetCommandFixed::~ModelResetCommandFixed()
{

}

bool ModelResetCommandFixed::emitPreSignal(const QModelIndex &srcParent, int srcStart, int srcEnd, const QModelIndex &destParent, int destRow)
{
    Q_UNUSED(srcParent);
    Q_UNUSED(srcStart);
    Q_UNUSED(srcEnd);
    Q_UNUSED(destParent);
    Q_UNUSED(destRow);

    m_model->beginResetModel();
    return true;
}

void ModelResetCommandFixed::emitPostSignal()
{
    m_model->endResetModel();
}

ModelChangeChildrenLayoutsCommand::ModelChangeChildrenLayoutsCommand(DynamicTreeModel* model, QObject* parent)
  : ModelChangeCommand(model, parent)
{

}

void ModelChangeChildrenLayoutsCommand::doCommand()
{
    const QPersistentModelIndex parent1 = findIndex(m_rowNumbers);
    const QPersistentModelIndex parent2 = findIndex(m_secondRowNumbers);

    QList<QPersistentModelIndex> parents;
    parents << parent1;
    parents << parent2;

    emit m_model->layoutAboutToBeChanged(parents);

    int rowSize1 = -1;
    int rowSize2 = -1;

    for (int column = 0; column < m_numCols; ++column)
    {
        {
          QList<qint64> &l = m_model->m_childItems[parent1.internalId()][column];
          rowSize1 = l.size();
          l.prepend(l.takeLast());
        }
        {
          QList<qint64> &l = m_model->m_childItems[parent2.internalId()][column];
          rowSize2 = l.size();
          l.append(l.takeFirst());
        }
    }

    // If we're changing one of the parent indexes, we need to ensure that we do that before
    // changing any children of that parent. The reason is that we're keeping parent1 and parent2
    // around as QPersistentModelIndex instances, and we query idx.parent() in the loop.
    QModelIndexList persistent = m_model->persistentIndexList();
    foreach (const QModelIndex &parent, parents) {
        int idx = persistent.indexOf(parent);
        if (idx != -1)
            persistent.move(idx, 0);
    }

    foreach (const QModelIndex &idx, persistent) {
        if (idx.parent() == parent1) {
            if (idx.row() == rowSize1 - 1) {
                m_model->changePersistentIndex(idx, m_model->createIndex(0, idx.column(), idx.internalPointer()));
            } else {
                m_model->changePersistentIndex(idx, m_model->createIndex(idx.row() + 1, idx.column(), idx.internalPointer()));
            }
        } else if (idx.parent() == parent2) {
            if (idx.row() == 0) {
                m_model->changePersistentIndex(idx, m_model->createIndex(rowSize2 - 1, idx.column(), idx.internalPointer()));
            } else {
                m_model->changePersistentIndex(idx, m_model->createIndex(idx.row() - 1, idx.column(), idx.internalPointer()));
            }
        }
    }

    emit m_model->layoutChanged(parents);
}