/*
* 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.text;
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;
import org.pentaho.reporting.libraries.formula.typing.TypeRegistry;
import org.pentaho.reporting.libraries.formula.typing.coretypes.TextType;
/**
* This function returns text where an old text is substituted with a new text.
*
* @author Cedric Pronzato
*/
public class SubstituteFunction implements Function
{
private static final long serialVersionUID = -1557813953499941337L;
public SubstituteFunction()
{
}
public TypeValuePair evaluate(final FormulaContext context,
final ParameterCallback parameters)
throws EvaluationException
{
final int parameterCount = parameters.getParameterCount();
if (parameterCount < 3 || parameterCount > 4)
{
throw EvaluationException.getInstance(LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE);
}
final TypeRegistry typeRegistry = context.getTypeRegistry();
final Type textType = parameters.getType(0);
final Object textValue = parameters.getValue(0);
final Type oldTextType = parameters.getType(1);
final Object oldTextValue = parameters.getValue(1);
final String text = typeRegistry.convertToText(textType, textValue);
final String oldText = typeRegistry.convertToText(oldTextType, oldTextValue);
if (oldText.length() == 0)
{
return new TypeValuePair(TextType.TYPE, text);
}
final Type newTextType = parameters.getType(2);
final Object newTextValue = parameters.getValue(2);
final String newText = typeRegistry.convertToText(newTextType, newTextValue);
if (parameterCount == 3)
{
int oldIndex = 0;
int index = text.indexOf(oldText);
if (index == -1)
{
return new TypeValuePair(TextType.TYPE, text);
}
final StringBuffer result = new StringBuffer(text.length());
while (index >= 0)
{
result.append(text.substring(oldIndex, index));
result.append(newText);
oldIndex = index + oldText.length();
index = text.indexOf(oldText, oldIndex);
}
result.append(text.substring(oldIndex));
return new TypeValuePair(TextType.TYPE, result.toString());
}
// Instead of replacing all occurences, the user only requested to replace
// a specific one.
final Type whichType = parameters.getType(3);
final Object whichValue = parameters.getValue(3);
final Number n = typeRegistry.convertToNumber(whichType, whichValue);
if (n.doubleValue() < 1)
{
throw EvaluationException.getInstance(
LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE);
}
final int nthOccurence = n.intValue();
int index = text.indexOf(oldText);
if (index == -1)
{
return new TypeValuePair(TextType.TYPE, text);
}
String result = text;
int counter = 1;
while (index >= 0)
{
if (counter == nthOccurence)
{
final StringBuffer buffer = new StringBuffer(result);
buffer.replace(index, index + oldText.length(), newText);
result = buffer.toString();
return new TypeValuePair(TextType.TYPE, result);
}
index = result.indexOf(oldText, index + 1);
counter += 1;
}
return new TypeValuePair(TextType.TYPE, result);
}
public String getCanonicalName()
{
return "SUBSTITUTE";
}
}