/*
* 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) 2006 - 2013 Pentaho Corporation and Contributors. All rights reserved.
*/
package org.pentaho.reporting.libraries.formula.function.information;
import org.pentaho.reporting.libraries.formula.EvaluationException;
import org.pentaho.reporting.libraries.formula.FormulaContext;
import org.pentaho.reporting.libraries.formula.LibFormulaErrorValue;
import org.pentaho.reporting.libraries.formula.function.Function;
import org.pentaho.reporting.libraries.formula.function.ParameterCallback;
import org.pentaho.reporting.libraries.formula.lvalues.TypeValuePair;
import org.pentaho.reporting.libraries.formula.typing.Type;
/**
* This function uses an index to return a value from a list of values.
* The first value index is 1, 2 for the second and so on.
*
* @author Cedric Pronzato
*/
public class ChooseFunction implements Function
{
private static final long serialVersionUID = 5328221291584681439L;
public ChooseFunction()
{
}
public String getCanonicalName()
{
return "CHOOSE";
}
public TypeValuePair evaluate(final FormulaContext context,
final ParameterCallback parameters)
throws EvaluationException
{
if(parameters.getParameterCount() <= 2)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
}
final Type indexType = parameters.getType(0);
final Object indexValue = parameters.getValue(0);
final int index= context.getTypeRegistry().convertToNumber(indexType, indexValue).intValue();
if (index < 1 || index >= parameters.getParameterCount())
{
// else
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
}
return new TypeValuePair(parameters.getType(index), parameters.getValue(index));
}
}