/**

  * 2008, Digitalis Informatica. All rights reserved. Distribuicao e Gestao de Informatica, Lda. Estrada de Paco de Arcos

  * num.9 - Piso -1 2780-666 Paco de Arcos Telefone: (351) 21 4408990 Fax: (351) 21 4408999 http://www.digitalis.pt

  */

 package pt.digitalis.dif.dem.objects.parameters.rules;

 import java.util.ArrayList;

 import java.util.List;

 import pt.digitalis.dif.dem.interfaces.IStageInstance;

 import pt.digitalis.dif.dem.objects.parameters.IParameter;

 import pt.digitalis.dif.dem.objects.parameters.ParameterList;

 import pt.digitalis.dif.dem.objects.parameters.types.AbstractParameter;

 import pt.digitalis.dif.exception.objects.ParameterException;

 /**

  * Exclusive parameter rule. Validates if the given parameter is not selected along with other exclusive fill parameter.

  * Only one can have a filled value.

  * 

  * @author Pedro Viegas <a href="mailto:pviegas@digitalis.pt">pviegas@digitalis.pt</a><br/>

  * @param <T>

  *            the parameter base type

  * @created Mar 31, 2009

  */

 public class ParameterRuleExclusive<T> extends AbstractParameterRule<T> {

     /**

      * Gets the validation result for the present parameter

      * 

      * @param stage

      *            the current stage

      * @param value

      *            the value to validate

      * @param initializationInProgress

      *            T if called within the dif parameter initialization

      * @param parameter

      *            the parameter for validation

      * @return the validation rule validation result

      * @throws ParameterException

      *             if the parameter does not exist

      */

     public ParameterRuleResult getValidationResult(IStageInstance stage, T value, boolean initializationInProgress,

             AbstractParameter<T> parameter) throws ParameterException

     {

         List<IParameter<?>> filledParameters = new ArrayList<IParameter<?>>();

         if (value == null || getParameters() == null || getParameters().isEmpty())

             return new ParameterRuleResult(true);

         else

         {

             ParameterList list = stage.getParameters().getAllAvailableParameters();

             for (String parameterID: getParameters())

             {

                 IParameter<?> param = null;

                 try

                 {

                     param = list.getParameter(parameterID);

                     if (param.getValue(stage.getContext()) != null)

                         filledParameters.add(param);

                 }

                 catch (ParameterException e)

                 {

                     filledParameters.add(param);

                 }

             }

             if (filledParameters.isEmpty())

                 return new ParameterRuleResult(true);

             else

             {

                 StringBuffer buffer = new StringBuffer();

                 buffer.append(this.getMessages(stage).get("onlyOne") + ": ");

                 buffer.append("\"" + getParameterName(stage, parameterID) + "\"");

                 for (IParameter<?> filledParam: filledParameters)

                     buffer.append(", \"" + getParameterName(stage, filledParam.getId()) + "\"");

                 return new ParameterRuleResult(buffer.toString());

             }

         }

     }

 }