/*!
* 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.plugin.jfreereport.reportcharts.collectors;

import org.jfree.data.category.DefaultCategoryDataset;
import org.jfree.data.general.Dataset;
import org.pentaho.reporting.engine.classic.core.DataRow;
import org.pentaho.reporting.engine.classic.core.function.Expression;

import java.util.ArrayList;
import java.util.Arrays;

/**
 * A slimmed down CategorySet Data collector. It collects a value for each series given.
 *
 * @author Thomas Morgner.
 */
public class CategorySetDataCollector extends AbstractCollectorFunction {
  private ArrayList<String> valueColumns;
  private String categoryColumn;

  public CategorySetDataCollector() {
    valueColumns = new ArrayList<String>();
  }

  public String getCategoryColumn() {
    return categoryColumn;
  }

  public void setCategoryColumn( final String categoryColumn ) {
    this.categoryColumn = categoryColumn;
  }

  public void setValueColumn( final int index, final String field ) {
    if ( valueColumns.size() == index ) {
      valueColumns.add( field );
    } else {
      valueColumns.set( index, field );
    }
  }

  public String getValueColumn( final int index ) {
    return valueColumns.get( index );
  }

  public int getValueColumnCount() {
    return valueColumns.size();
  }

  public String[] getValueColumn() {
    return valueColumns.toArray( new String[ valueColumns.size() ] );
  }

  public void setValueColumn( final String[] fields ) {
    this.valueColumns.clear();
    this.valueColumns.addAll( Arrays.asList( fields ) );
  }

  protected Dataset createNewDataset() {
    return new DefaultCategoryDataset();
  }

  protected void buildDataset() {
    final DataRow dataRow = getDataRow();
    final Object categoryObject = dataRow.get( getCategoryColumn() );
    if ( categoryObject instanceof Comparable == false ) {
      return;
    }

    final Comparable categoryComparable = (Comparable) categoryObject;

    // I love to be paranoid!
    final DefaultCategoryDataset categoryDataset = (DefaultCategoryDataset) getDataSet();

    final int maxIndex = this.valueColumns.size();
    for ( int i = 0; i < maxIndex; i++ ) {
      final Comparable seriesName = querySeriesValue( i );
      if ( seriesName == null ) {
        continue;
      }
      final Object valueObject = dataRow.get( getValueColumn( i ) );

      final Number value = ( valueObject instanceof Number ) ? (Number) valueObject : null;

      final Number existingValue =
        CollectorFunctionUtil.queryExistingValueFromDataSet( categoryDataset, seriesName, categoryComparable );
      if ( existingValue != null ) {
        if ( value != null ) {
          categoryDataset.setValue( CollectorFunctionUtil.add( existingValue, value ), seriesName, categoryComparable );
        }
      } else {
        categoryDataset.setValue( value, seriesName, categoryComparable );
      }
    }
  }

  /**
   * Return a completly separated copy of this function. The copy does no longer share any changeable objects with the
   * original function.
   *
   * @return a copy of this function.
   */
  public Expression getInstance() {
    final CategorySetDataCollector expression = (CategorySetDataCollector) super.getInstance();
    expression.valueColumns = (ArrayList<String>) valueColumns.clone();
    return expression;
  }
}