/*===========================================================================*\
*                                                                            *
*                              OpenFlipper                                   *
 *           Copyright (c) 2001-2015, RWTH-Aachen University                 *
 *           Department of Computer Graphics and Multimedia                  *
 *                          All rights reserved.                             *
 *                            www.openflipper.org                            *
 *                                                                           *
 *---------------------------------------------------------------------------*
 * This file is part of OpenFlipper.                                         *
 *---------------------------------------------------------------------------*
 *                                                                           *
 * Redistribution and use in source and binary forms, with or without        *
 * modification, are permitted provided that the following conditions        *
 * are met:                                                                  *
 *                                                                           *
 * 1. Redistributions of source code must retain the above copyright notice, *
 *    this list of conditions and the following disclaimer.                  *
 *                                                                           *
 * 2. Redistributions in binary form must reproduce the above copyright      *
 *    notice, this list of conditions and the following disclaimer in the    *
 *    documentation and/or other materials provided with the distribution.   *
 *                                                                           *
 * 3. Neither the name of the copyright holder nor the names of its          *
 *    contributors may be used to endorse or promote products derived from   *
 *    this software without specific prior written permission.               *
 *                                                                           *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS       *
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED *
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A           *
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER *
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,  *
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,       *
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR        *
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF    *
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING      *
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS        *
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.              *
*                                                                            *
\*===========================================================================*/

/*===========================================================================*\
*                                                                            *
*   $Revision$                                                       *
*   $LastChangedBy$                                                *
*   $Date$                     *
*                                                                            *
\*===========================================================================*/

#include "TreeModel.hh"

  #include <QtWidgets>


#include <OpenFlipper/BasePlugin/PluginFunctions.hh>
#include <OpenFlipper/common/GlobalOptions.hh>

#include <ObjectTypes/Light/LightWidget.hh>


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

/** \brief Constructor
 *
 * @param _parent parent Object
 */
TreeModel::TreeModel( QObject *_parent) : QAbstractItemModel(_parent)
{
  rootItem_ = new TreeItem( -1, "ROOT", DATA_UNKNOWN, 0);
}


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

/** \brief Destructor
 *
 */
TreeModel::~TreeModel()
{

}


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

int TreeModel::columnCount(const QModelIndex &/*_parent*/) const
{
  // Name,Visible,Source,Target -> 4
  return (4);
}


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

/** \brief Returns the data stored under the given role for the item referred to by the index
 *
 * @param _index a ModelIndex that defines the item in the tree
 * @param _role defines the kind of data requested
 * @return requested data
 */
QVariant TreeModel::data(const QModelIndex &_index, int _role) const
{

  // Skip invalid requests
  if (!_index.isValid())
      return QVariant();

  // Get the corresponding tree item
  TreeItem *item = static_cast<TreeItem*>(_index.internalPointer());

  if ( item == rootItem_ ) {
    std::cerr << "Root" << std::endl;
  }

  // Set the background color of the objects row
  if ( _role == Qt::BackgroundRole ) {
    if ( !item->visible() ) {
      return QVariant( QBrush(QColor(100,100,100) ) );
    }
  }
  


  switch (_index.column() ) {
  // Name
  case 0 :

    // If we are setting the name, also add the icon
    if ( _role == Qt::DecorationRole ) {
      if (item->dataType() == DATA_LIGHT)
      {
        LightObject* light = 0;
        if (item->id() != -1 && PluginFunctions::getObject( item->id(), light ) ) {
          if (light != 0 && !light->lightSource()->enabled())
            return QVariant (QIcon (OpenFlipper::Options::iconDirStr()+OpenFlipper::Options::dirSeparator()+"LightOff.png"));
        }
      }
      return QVariant( typeIcon(item->dataType()) );
    }

    if (_role != Qt::DisplayRole && _role != Qt::EditRole )
      return QVariant();

    return QVariant(item->name());

    break;
    // Visible
  case 1 :
    if (_role == Qt::CheckStateRole ) {
      bool visible = false;
      // target group
      if (item->isGroup() && item->childCount() > 0)
      {
        QList< TreeItem* > children = item->getLeafs();

        visible = children[0]->visible();
        for (int i=0; i < children.size() ; ++i)
        {
          if (visible != children[i]->visible())
            return QVariant(Qt::PartiallyChecked);
        }
      }
      else
        visible = item->visible();
      return (visible) ? QVariant(Qt::Checked) : QVariant(Qt::Unchecked);
    }
    return QVariant();
    // Source
  case 2 :
    if (_role == Qt::CheckStateRole ) {
      bool source = false;
      // target group
      if (item->isGroup() && item->childCount() > 0)
      {
        QList< TreeItem* > children = item->getLeafs();

        source = children[0]->source();
        for (int i=0; i < children.size() ; ++i)
        {
          if (source != children[i]->source())
            return QVariant(Qt::PartiallyChecked);
        }
      }
      else
        source = item->source();
      return (source) ? QVariant(Qt::Checked) : QVariant(Qt::Unchecked);
    }
    return QVariant();

    // Target
  case 3 :
    if (_role == Qt::CheckStateRole ) {
      bool target = false;
      // target group
      if (item->isGroup() && item->childCount() > 0)
      {
        QList< TreeItem* > children = item->getLeafs();

        target = children[0]->target();
        for (int i=0; i < children.size() ; ++i)
        {
          if (target != children[i]->target())
            return QVariant(Qt::PartiallyChecked);
        }
      }
      else
        target = item->target();
      return (target) ? QVariant(Qt::Checked) : QVariant(Qt::Unchecked);
    }
    return QVariant();

  default:
    return QVariant();
  }
  return QVariant();

}


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

/** \brief Returns the item flags for the given index
 *
 * @param _index ModelIndex that defines an item in the tree
 * @return flags for the given ModelIndex
 */
Qt::ItemFlags TreeModel::flags(const QModelIndex &_index) const
{
    if (!_index.isValid())
        return 0;

    Qt::ItemFlags flags = 0;

    // Show/Source/Target
    if ( ( _index.column() == 1 ) ||
         ( _index.column() == 2 ) ||
         ( _index.column() == 3 ) )
      flags = Qt::ItemIsUserCheckable | Qt::ItemIsEnabled | Qt::ItemIsSelectable;
    else
    if ( _index.column() == 0 )
      flags = Qt::ItemIsEditable | Qt::ItemIsEnabled | Qt::ItemIsSelectable;
    else
      flags = Qt::ItemIsEnabled;

  // Get the corresponding tree item
  TreeItem *item = static_cast<TreeItem*>(_index.internalPointer());

  if ( item->isGroup() )
    return flags | Qt::ItemIsDragEnabled | Qt::ItemIsDropEnabled;
  else
    return flags | Qt::ItemIsDragEnabled;
}


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

/** \brief Returns the data in the header
 *
 * @param _section the column in the header
 * @param _orientation header orientation (only horizontal handled)
 * @param _role the role that defines the type of data
 * @return the requested data
 */
QVariant TreeModel::headerData(int _section, Qt::Orientation _orientation,
                                int _role) const
{
    if (_orientation == Qt::Horizontal && _role == Qt::DisplayRole) {

      switch (_section) {
        case 0 : return QVariant("Name");
        case 1 : return QVariant("Show");
        case 2 : return QVariant("Source");
        case 3 : return QVariant("Target");
        default :
          return QVariant();
      }
    }
    return QVariant();
}


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

/** \brief Returns the index of the item in the model specified by the given row, column and parent index.
 *
 * @param _row the row
 * @param _column the column
 * @param _parent parent item
 * @return corresponding ModelIndex
 */
QModelIndex TreeModel::index(int _row, int _column,const QModelIndex &_parent) const
{
//     if (!hasIndex(row, column, _parent))
//         return QModelIndex();

    TreeItem *parentItem;

    if (!_parent.isValid())
        parentItem = rootItem_;
    else
        parentItem = static_cast<TreeItem*>(_parent.internalPointer());

    TreeItem *childItem = parentItem->child(_row);
    if (childItem)
        return createIndex(_row, _column, childItem);
    else
        return QModelIndex();
}


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

/** \brief Return index of parent item
 *
 * @param _index a ModelIndex
 * @return parent of the given ModelIndex
 */
QModelIndex TreeModel::parent(const QModelIndex &_index) const
{
    if (!_index.isValid())
        return QModelIndex();

    TreeItem *childItem = static_cast<TreeItem*>(_index.internalPointer());
    TreeItem *parentItem = childItem->parent();

    if (parentItem == rootItem_)
        return QModelIndex();

    return createIndex(parentItem->row(), 0, parentItem);
}


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

/** \brief Returns the number of rows under given parent
 *
 * @param _parent parent Item
 * @return number of rows that are children of given parent
 */
int TreeModel::rowCount(const QModelIndex &_parent) const
{
    TreeItem *parentItem;
    if (_parent.column() > 0)
        return 0;

    if (!_parent.isValid())
        parentItem = rootItem_;
    else
        parentItem = static_cast<TreeItem*>(_parent.internalPointer());

    return parentItem->childCount();
}
//******************************************************************************

/** \brief The object with the given id has been changed. Update the model.
 *
 * @param _id  id of an object
 */
void TreeModel::objectChanged(int _id) {

  if ( _id != -1 ){

    BaseObject* obj = 0;
    PluginFunctions::getObject(_id, obj);

    TreeItem* item = rootItem_->childExists(_id);

    //if internal and external representation are both valid
    if (obj != 0 && item != 0){
      //update the name
      bool updateRow = false;
      if ( obj->name() != item->name() ){

        item->name( obj->name() );
        updateRow = true;
      }

      //update visibility
      if ( obj->visible() != item->visible() ){

        item->visible( obj->visible() );
        updateRow = true;
      }

      //update source flag
      if ( obj->source() != item->source() ){

        item->source( obj->source() );
        updateRow = true;
      }

      //update target flag
      if ( obj->target() != item->target() ){

        item->target( obj->target() );
        updateRow = true;
      }
      if (updateRow)
      {
        //TODO actually we do not need to update the whole row but single column somehow doesn't work
        QModelIndex index0 = getModelIndex(item,0);
        QModelIndex index1 = getModelIndex(item,3);

        if ( index0.isValid() && index1.isValid() ){
          //the whole row has to be updated because of the grey background-color
          emit dataChanged( index0, index1);
        }
      }

      //update parent
      if ( obj->parent() == PluginFunctions::objectRoot() && isRoot( item->parent() ) ){
        return;
      }else if ( obj->parent() == PluginFunctions::objectRoot() && !isRoot( item->parent() ) ){
        moveItem(item, rootItem_ );
      }else if ( obj->parent()->id() != item->parent()->id() ){
        TreeItem* parent = rootItem_->childExists( obj->parent()->id() );

        if (parent != 0)
          moveItem(item, parent );
      }

    }
  }

}


/** \brief The object with the given id has been added. add it to the internal tree
 *
 * @param _object The added object
 */
void TreeModel::objectAdded(BaseObject* _object){

  // check if item already in model tree
  // this function can be called by addEmpty and fileOpened
  // both will be called by fileOpened such that the item
  // already exists
  if( rootItem_->childExists( _object->id() )) 
    return;

  TreeItem* parent = 0;
  //find the parent
  if ( _object->parent() == PluginFunctions::objectRoot() )
    parent = rootItem_;
  else
    parent = rootItem_->childExists( _object->parent()->id() );

  if (parent != 0){
    QModelIndex parentIndex = getModelIndex(parent, 0);

    beginInsertRows(parentIndex, parent->childCount(), parent->childCount()); //insert at the bottom

    TreeItem* item = new TreeItem( _object->id(), _object->name(), _object->dataType(), parent);

    parent->appendChild( item );

    endInsertRows();
  }

  objectChanged( _object->id() );
}

/** \brief The object with the given id has been deleted. delete it from the internal tree
 *
 * @param _id id of the object
 */
void TreeModel::objectDeleted(int _id){

  TreeItem* item = rootItem_->childExists(_id);

  if ( item != 0 && !isRoot(item) ){

    QModelIndex itemIndex   = getModelIndex(item, 0);
    QModelIndex parentIndex = itemIndex.parent();

    beginRemoveRows( parentIndex, itemIndex.row(), itemIndex.row() );

    item->parent()->removeChild(item);
    item->deleteSubtree();

    delete item;

    endRemoveRows();
  }
}

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

/** \brief move the item to a new parent
 *
 * @param _item the item
 * @param _parent new parent
 */
void TreeModel::moveItem(TreeItem* _item, TreeItem* _parent ){

  QModelIndex itemIndex   = getModelIndex(_item, 0);
  QModelIndex oldParentIndex = itemIndex.parent();
  QModelIndex newParentIndex = getModelIndex(_parent, 0);

  beginMoveRows ( oldParentIndex, itemIndex.row(), itemIndex.row(), newParentIndex,0 );
    _item->parent()->removeChild(_item);
    _item->setParent( _parent );
    _parent->appendChild( _item );
  endMoveRows();
}

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

/** \brief Return item at given index
 *
 * @param _index a ModelIndex
 * @return item at given index
 */
TreeItem* TreeModel::getItem(const QModelIndex &_index) const
{
    if (_index.isValid()) {
        TreeItem *item = static_cast<TreeItem*>(_index.internalPointer());
        if (item) return item;
    }
    return rootItem_;
}


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

/** \brief Return item-name at given index
 *
 * @param  _index A ModelIndex
 * @return name of the item at given index
 */
QString TreeModel::itemName(const QModelIndex &_index) const
{
    if (_index.isValid()) {
        TreeItem *item = static_cast<TreeItem*>(_index.internalPointer());
        if (item)
          return item->name();
    }
    return "not found";
}

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

/** \brief Return item-id at given index
 *
 * @param _index a ModelIndex
 * @return item-id at given index
 */
int TreeModel::itemId(const QModelIndex &_index) const
{
    if (_index.isValid()) {
        TreeItem *item = static_cast<TreeItem*>(_index.internalPointer());
        if (item)
          return item->id();
    }
    return -1;
}

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

/** \brief Return index of given item
 *
 * Warning: Only use this function if you know that all ModelIndices are created
 *
 * @param _object an object
 * @param _column a column
 * @return index of object and column
 */
QModelIndex TreeModel::getModelIndex(TreeItem* _object, int _column ){

  // root item gets an invalid QModelIndex
  if ( _object == rootItem_ )
    return QModelIndex();

  QModelIndex index = createIndex(_object->row(), _column, _object);

  return index;
}

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

bool TreeModel::setData(const QModelIndex &_index, const QVariant &_value, int /*role*/)
{

  emit dataChangedInside( itemId(_index), _index.column(), _value );

  
  return true;
}


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

/** \brief return if an object is equal to the root object
 *
 * @param _item the item to be checked
 * @return is it the root object?
 */
bool TreeModel::isRoot(TreeItem * _item) {
  return ( _item == rootItem_ );
}

/*******************************************************************************
        drag & drop stuff
 *******************************************************************************/

/** \brief return the supported drop actions
 *
 * @return drop actions
 */
Qt::DropActions TreeModel::supportedDropActions() const
{
    return /*Qt::CopyAction |*/ Qt::MoveAction;
}


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

/** \brief return the mimeType for drag & drop
 *
 * @return the mimeType
 */
QStringList TreeModel::mimeTypes() const
{
    QStringList types;
    types << "DataControl/dragDrop";
    return types;
}


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

/** \brief generate mimeData for given ModelIndexes
 *
 * @param _indexes list of ModelIndexes
 * @return the mimeData
 */
QMimeData* TreeModel::mimeData(const QModelIndexList& _indexes) const
{
    QMimeData *mimeData = new QMimeData();
    QByteArray encodedData;

    QDataStream stream(&encodedData, QIODevice::WriteOnly);

    QVector< int > rows;

    foreach (QModelIndex index, _indexes) {
        if (index.isValid()) {

          if (!rows.contains( index.row() ) ){
            TreeItem *item = getItem(index);
            stream << item->id();

            rows.push_back( index.row() );
          }
        }
    }

    mimeData->setData("DataControl/dragDrop", encodedData);
    return mimeData;
}


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

bool TreeModel::dropMimeData( const QMimeData *_data,
                              Qt::DropAction _action,
                              int /*_row*/,
                              int /*_column*/,
                              const QModelIndex &_parent)
{
  if (_action == Qt::IgnoreAction)
      return true;

  if (!_data->hasFormat("DataControl/dragDrop"))
      return false;

  QByteArray encodedData = _data->data("DataControl/dragDrop");
  QDataStream stream(&encodedData, QIODevice::ReadOnly);

  QVector< int > ids;

  while (!stream.atEnd()) {
    int id;
    stream >> id;

    ids.push_back( id );
  }

  if (ids.count() == 0)
    return false;

  //get new parent
  TreeItem *newParent = getItem(_parent);

  if ( newParent == 0 || !newParent->isGroup() )
    return false;

  //and move all objects
  for (int i = 0; i < ids.count(); i++){
    //tell the DataControlPlugin to move the corresponding BaseObject
    emit moveBaseObject( ids[i], newParent->id()  );
  }

  return true;

 }
//******************************************************************************
TreeItem *TreeModel::getItem(const int _id) const
{
  return rootItem_->childExists(_id);
}