/*
* 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.coretypes.TextType;

import java.text.NumberFormat;

/**
 * This function returns the given value as text.
 *
 * @author Cedric Pronzato
 */
public class DollarFunction implements Function {
  private static final long serialVersionUID = 3505313019941429911L;

  public DollarFunction() {
  }

  public TypeValuePair evaluate( final FormulaContext context, final ParameterCallback parameters )
    throws EvaluationException {
    final int parameterCount = parameters.getParameterCount();
    if ( parameterCount < 1 || parameterCount > 2 ) {
      throw EvaluationException.getInstance( LibFormulaErrorValue.ERROR_ARGUMENTS_VALUE );
    }
    final Type type1 = parameters.getType( 0 );
    final Object value1 = parameters.getValue( 0 );
    final Number result = context.getTypeRegistry().convertToNumber( type1, value1 );
    if ( result == null ) {
      throw EvaluationException.getInstance( LibFormulaErrorValue.ERROR_INVALID_ARGUMENT_VALUE );
    }

    final NumberFormat currencyInstance =
      NumberFormat.getCurrencyInstance( context.getLocalizationContext().getLocale() );

    if ( parameterCount == 2 ) {
      final Type typeDecimals = parameters.getType( 1 );
      final Object valueDecimals = parameters.getValue( 1 );
      final Number resultDecimals = context.getTypeRegistry().convertToNumber( typeDecimals, valueDecimals );
      currencyInstance.setMaximumFractionDigits( resultDecimals.intValue() );
      currencyInstance.setMinimumFractionDigits( resultDecimals.intValue() );
    }

    return new TypeValuePair( TextType.TYPE, currencyInstance.format( result ) );
  }

  public String getCanonicalName() {
    return "FIXED";
  }

}