/*
 * Copyright (c) 2012, Willow Garage, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of the Willow Garage, Inc. 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 OWNER 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.
 */

#include <stdio.h>

#include <QStringList>
#include <QMimeData>

#include "rviz/properties/property.h"

#include "rviz/properties/property_tree_model.h"

namespace rviz
{

PropertyTreeModel::PropertyTreeModel( Property* root_property, QObject* parent )
  : QAbstractItemModel( parent )
  , root_property_( root_property )
{
  root_property_->setModel( this );
}

PropertyTreeModel::~PropertyTreeModel()
{
  delete root_property_;
}

Property* PropertyTreeModel::getProp( const QModelIndex& index ) const
{
  if( index.isValid() )
  {
    Property* prop = static_cast<Property*>( index.internalPointer() );
    if( prop )
    {
      return prop;
    }
  }
  return root_property_;
}

Qt::ItemFlags PropertyTreeModel::flags( const QModelIndex& index ) const
{
  if( !index.isValid() )
  {
    root_property_->getViewFlags( 0 );
  }
  Property* property = getProp( index );
  return property->getViewFlags( index.column() );
}

QModelIndex PropertyTreeModel::index( int row, int column, const QModelIndex& parent_index ) const
{
  if( parent_index.isValid() && parent_index.column() != 0 )
  {
    return QModelIndex();
  }
  Property* parent = getProp( parent_index );

  Property* child = parent->childAt( row );
  if( child )
  {
    return createIndex( row, column, child );
  }
  else
  {
    return QModelIndex();
  }
}

QModelIndex PropertyTreeModel::parent( const QModelIndex& child_index ) const
{
  if( !child_index.isValid() )
  {
    return QModelIndex();
  }
  Property* child = getProp( child_index );
  return parentIndex( child );
}

QModelIndex PropertyTreeModel::parentIndex( const Property* child ) const
{
  if( !child )
  {
    return QModelIndex();
  }
  Property* parent = child->getParent();
  if( parent == root_property_ || !parent )
  {
    return QModelIndex();
  }
  return indexOf( parent );
}

int PropertyTreeModel::rowCount( const QModelIndex& parent_index ) const
{
  return getProp( parent_index )->numChildren();
}

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

  return getProp( index )->getViewData( index.column(), role );
}

QVariant PropertyTreeModel::headerData( int  /*section*/, Qt::Orientation  /*orientation*/, int  /*role*/ ) const
{
  // we don't use headers.
  return QVariant();
}

bool PropertyTreeModel::setData( const QModelIndex& index, const QVariant& value, int role )
{
  Property *property = getProp( index );

  if( property->getValue().type() == QVariant::Bool && role == Qt::CheckStateRole )
  {
    if( property->setValue( value.toInt() != Qt::Unchecked ))
    {
      return true;
    }
  }

  if( role != Qt::EditRole )
  {
    return false;
  }

  if( property->setValue( value ))
  {
    return true;
  }
  return false;
}

/** @brief Override from QAbstractItemModel.  Returns a
 * (non-standard) mime-encoded version of the given indexes.
 *
 * Returns the model indexes encoded using pointer values, which
 * means they will only work within the application this is compiled
 * into. */
QMimeData* PropertyTreeModel::mimeData( const QModelIndexList& indexes ) const
{
  if( indexes.count() <= 0 )
  {
    return 0;
  }
  QStringList types = mimeTypes();
  if( types.isEmpty() )
  {
    return 0;
  }
  QMimeData *data = new QMimeData();
  QString format = types.at(0);
  QByteArray encoded;
  QDataStream stream( &encoded, QIODevice::WriteOnly );

  QModelIndexList::ConstIterator it = indexes.begin();
  for( ; it != indexes.end(); ++it )
  {
    if( (*it).column() == 0 )
    {
      void* pointer = (*it).internalPointer();
      stream.writeRawData( (char*)&pointer, sizeof( void* ));
    }
  }

  data->setData( format, encoded );
  return data;
}

/** @brief Override from QAbstractItemModel.  Takes a (non-standard)
 * mime-encoded version of an index list and drops it at the
 * destination.
 *
 * The model indexes are encoded using pointer values (by
 * mimeData()), which means they will only work within the
 * application this is compiled into. */
bool PropertyTreeModel::dropMimeData( const QMimeData* data,
                                      Qt::DropAction action,
                                      int dest_row, int  /*dest_column*/,
                                      const QModelIndex& dest_parent )
{
  if( !data || action != Qt::MoveAction )
  {
    return false;
  }
  QStringList types = mimeTypes();
  if( types.isEmpty() )
  {
    return false;
  }
  QString format = types.at(0);
  if( !data->hasFormat( format ))
  {
    return false;
  }
  QByteArray encoded = data->data( format );
  QDataStream stream( &encoded, QIODevice::ReadOnly );

  Property* dest_parent_property = getProp( dest_parent );

  QList<Property*> source_properties;

  // Decode the mime data.
  while( !stream.atEnd() )
  {
    void* pointer;
    if( sizeof( void* ) != stream.readRawData( (char*)&pointer, sizeof( void* )))
    {
      printf("ERROR: dropped mime data has invalid pointer data.\n");
      return false;
    }
    Property* prop = static_cast<Property*>( pointer );
    if( prop == dest_parent_property || prop->isAncestorOf( dest_parent_property ))
    {
      // Can't drop a row into its own child.
      return false;
    }
    source_properties.append( prop );
  }

  if( dest_row == -1 )
  {
    dest_row = dest_parent_property->numChildren();
  }
  for( int i = 0; i < source_properties.size(); i++ )
  {
    Property* prop = source_properties.at( i );
    // When moving multiple items, source indices can change.
    // Therefore we ask each property for its row just before we move
    // it.
    int source_row = prop->rowNumberInParent();

    prop->getParent()->takeChildAt( source_row );

    if( dest_parent_property == prop->getParent() && dest_row > source_row )
    {
      dest_row--;
    }

    dest_parent_property->addChild( prop, dest_row );
    dest_row++;
  }

  return true;
}

QStringList PropertyTreeModel::mimeTypes() const
{
  QStringList result;
  result.append( "application/x-rviz-" + drag_drop_class_ );
  return result;
}

QModelIndex PropertyTreeModel::indexOf( Property* property ) const
{
  if( property == root_property_ || !property )
  {
    return QModelIndex();
  }
  return createIndex( property->rowNumberInParent(), 0, property );
}

void PropertyTreeModel::emitDataChanged( Property* property )
{
  if( property->shouldBeSaved() )
  {
    Q_EMIT configChanged();
  }
  QModelIndex left_index = indexOf( property );
  QModelIndex right_index = createIndex( left_index.row(), 1, left_index.internalPointer() );
  Q_EMIT dataChanged( left_index, right_index );
}

void PropertyTreeModel::beginInsert( Property* parent_property, int row_within_parent, int count )
{
  // printf( "PropertyTreeModel::beginInsert() into %s row %d, %d rows.  Persistent indices:\n",
  //         qPrintable( parent_property->getName()), row_within_parent, count );
  // printPersistentIndices();

  beginInsertRows( indexOf( parent_property ), row_within_parent, row_within_parent + count - 1 );
}

void PropertyTreeModel::endInsert()
{
  endInsertRows();
  // printf( "PropertyTreeModel::endInsert()\n" );
}

void PropertyTreeModel::beginRemove( Property* parent_property, int row_within_parent, int count )
{
  // printf( "PropertyTreeModel::beginRemove() from %s row %d, %d rows.  Persistent indices:\n",
  //         qPrintable( parent_property->getName()), row_within_parent, count );
  // printPersistentIndices();

  beginRemoveRows( indexOf( parent_property ), row_within_parent, row_within_parent + count - 1 );
}

void PropertyTreeModel::endRemove()
{
  endRemoveRows();
//  printf( "PropertyTreeModel::endRemove()\n" );
}

void PropertyTreeModel::expandProperty( Property* property )
{
  Q_EMIT expand( indexOf( property ));
}

void PropertyTreeModel::collapseProperty( Property* property )
{
  Q_EMIT collapse( indexOf( property ));
}

void PropertyTreeModel::printPersistentIndices()
{
  QModelIndexList indexes = persistentIndexList();
  QModelIndexList::ConstIterator it = indexes.begin();
  for( ; it != indexes.end(); ++it )
  {
    if( !(*it).isValid() )
    {
      printf( "  invalid index\n" );
    }
    else
    {
      Property* prop = getProp( *it );
      if( !prop )
      {
        printf( "  null property\n" );
      }
      else
      {
        printf( "  prop name '%s'\n", qPrintable( prop->getName() ));
      }
    }
  }  
}

} // end namespace rviz
