/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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 Lesser General Public License for more details.
*
* Copyright (c) 2002-2013 Pentaho Corporation..  All rights reserved.
*/

package org.pentaho.reporting.designer.core.editor.report;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.reporting.engine.classic.core.Section;
import org.pentaho.reporting.engine.classic.core.layout.model.LogicalPageBox;
import org.pentaho.reporting.engine.classic.core.layout.model.RenderBox;
import org.pentaho.reporting.engine.classic.core.layout.model.RenderNode;
import org.pentaho.reporting.engine.classic.core.layout.process.IterateSimpleStructureProcessStep;
import org.pentaho.reporting.engine.classic.core.util.InstanceID;
import org.pentaho.reporting.engine.classic.core.util.geom.StrictBounds;

import java.util.HashSet;

public class SelectLayoutNodes extends IterateSimpleStructureProcessStep {
  private static final Log logger = LogFactory.getLog( SelectLayoutNodes.class );
  private HashSet<InstanceID> ids;
  private StrictBounds bounds;

  public SelectLayoutNodes() {
    ids = new HashSet<InstanceID>();
  }

  public StrictBounds select( final HashSet<InstanceID> ids,
                              final LogicalPageBox box,
                              final Section section ) {
    if ( ids == null ) {
      throw new NullPointerException();
    }
    this.ids.clear();
    this.ids.addAll( ids );
    this.bounds = null;
    startProcessing( box );
    if ( this.bounds == null ) {
      recurse( box, section.getParentSection() );
      if ( this.bounds == null ) {
        return new StrictBounds();
      }
    }
    return this.bounds;
  }

  // todo: Condense this into one run where we collect all bounds for all parents ...
  private void recurse( final LogicalPageBox box, final Section section ) {
    if ( section != null ) {
      this.ids.clear();
      this.ids.add( section.getObjectID() );
      this.bounds = null;
      startProcessing( box );
      if ( this.bounds == null ) {
        //logger.debug("Failed to collect bounds for report of section " + section);
        recurse( box, section.getParentSection() );
        return;
      }

      //logger.debug("Generating bounds for empty section " + section);
      this.bounds.setRect( this.bounds.getX(), this.bounds.getY(), this.bounds.getWidth(), 0 );
    }
  }

  private boolean isValidDrawTarget( RenderNode node ) {
    while ( node != null ) {
      if ( ids.contains( node.getInstanceId() ) ) {
        return true;
      }
      node = node.getParent();
    }
    return false;
  }

  protected void processOtherNode( final RenderNode node ) {
    if ( isValidDrawTarget( node ) ) {
      if ( bounds == null ) {
        bounds = new StrictBounds( node.getX(), node.getY(), node.getWidth(), node.getHeight() );
      } else {
        bounds.add( node.getX(), node.getY(), node.getWidth(), node.getHeight() );
      }
    }
  }

  protected boolean startBox( final RenderBox box ) {
    if ( isValidDrawTarget( box ) ) {
      if ( bounds == null ) {
        bounds = new StrictBounds( box.getX(), box.getY(), box.getWidth(), box.getHeight() );
      } else {
        bounds.add( box.getX(), box.getY(), box.getWidth(), box.getHeight() );
      }
    }
    return true;
  }
}