/**
    * Copyright 2005-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.rice.krad.datadictionary.validation.processor;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.util.RiceKeyConstants;
  import org.kuali.rice.krad.datadictionary.exception.AttributeValidationException;
  import org.kuali.rice.krad.datadictionary.validation.AttributeValueReader;
  import org.kuali.rice.krad.datadictionary.validation.ErrorLevel;
  import org.kuali.rice.krad.datadictionary.validation.ValidationUtils;
  import org.kuali.rice.krad.datadictionary.validation.constraint.Constraint;
  import org.kuali.rice.krad.datadictionary.validation.constraint.MustOccurConstraint;
  import org.kuali.rice.krad.datadictionary.validation.constraint.PrerequisiteConstraint;
  import org.kuali.rice.krad.datadictionary.validation.result.ConstraintValidationResult;
  import org.kuali.rice.krad.datadictionary.validation.result.DictionaryValidationResult;
  import org.kuali.rice.krad.datadictionary.validation.result.ProcessorResult;
  import org.kuali.rice.krad.uif.UifConstants;
  
  import java.util.List;
  
  /**
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class MustOccurConstraintProcessor extends BasePrerequisiteConstraintProcessor<MustOccurConstraint> {
  
      private static final String CONSTRAINT_NAME = "must occur constraint";
      private static final String FALLBACK_KEY = "mustoccursFallback";
  
      /**
       * @see org.kuali.rice.krad.datadictionary.validation.processor.ConstraintProcessor#process(org.kuali.rice.krad.datadictionary.validation.result.DictionaryValidationResult,
       *      Object, org.kuali.rice.krad.datadictionary.validation.constraint.Constraint,
       *      org.kuali.rice.krad.datadictionary.validation.AttributeValueReader)
       */
      @Override
      public ProcessorResult process(DictionaryValidationResult result, Object value, MustOccurConstraint constraint,
              AttributeValueReader attributeValueReader) throws AttributeValidationException {
  
          if (ValidationUtils.isNullOrEmpty(value)) {
              return new ProcessorResult(result.addSkipped(attributeValueReader, CONSTRAINT_NAME));
          }
  
          ConstraintValidationResult constraintValidationResult = new ConstraintValidationResult(CONSTRAINT_NAME);
          if (StringUtils.isNotBlank(constraint.getMessageKey())) {
              constraintValidationResult.setConstraintLabelKey(constraint.getMessageKey());
          } else {
              constraintValidationResult.setConstraintLabelKey(
                      UifConstants.Messages.VALIDATION_MSG_KEY_PREFIX + FALLBACK_KEY);
          }
  
          constraintValidationResult.setErrorParameters(constraint.getValidationMessageParamsArray());
  
          // If the processing of this constraint is not successful then it's an error
          if (!processMustOccurConstraint(constraintValidationResult, constraint, attributeValueReader)) {
              // if attributeName is null, use the entry name since we are processing a must occur constraint that may be referencing multiple attributes
              if (attributeValueReader.getAttributeName() == null) {
                  constraintValidationResult.setAttributeName(attributeValueReader.getEntryName());
              } else {
                  constraintValidationResult.setAttributeName(attributeValueReader.getAttributeName());
                  constraintValidationResult.setAttributePath(attributeValueReader.getPath());
              }
              constraintValidationResult.setError(RiceKeyConstants.ERROR_OCCURS);
          }
  
          // Store the label key (if one exists) for this constraint on the constraint validation result so it can be shown later
  
          // Add it to the DictionaryValidationResult object
          result.addConstraintValidationResult(attributeValueReader, constraintValidationResult);
  
          return new ProcessorResult(constraintValidationResult);
  
      }
  
      @Override
      public String getName() {
          return CONSTRAINT_NAME;
      }
  
      /**
       * @see org.kuali.rice.krad.datadictionary.validation.processor.ConstraintProcessor#getConstraintType()
       */
      @Override
      public Class<? extends Constraint> getConstraintType() {
          return MustOccurConstraint.class;
      }
  
      protected boolean processMustOccurConstraint(ConstraintValidationResult topLevelResult,
             MustOccurConstraint constraint,
             AttributeValueReader attributeValueReader) throws AttributeValidationException {
 
         boolean isSuccessful = false;
         int trueCount = 0;
 
         List<PrerequisiteConstraint> prerequisiteConstraints = constraint.getPrerequisiteConstraints();
         if (prerequisiteConstraints != null) {
             for (PrerequisiteConstraint prerequisiteConstraint : prerequisiteConstraints) {
                 ConstraintValidationResult constraintValidationResult = processPrerequisiteConstraint(
                         prerequisiteConstraint, attributeValueReader);
                 constraintValidationResult.setConstraintLabelKey(prerequisiteConstraint.getMessageKey());
                 constraintValidationResult.setErrorParameters(prerequisiteConstraint.getValidationMessageParamsArray());
                 // Add the result of each prerequisite constraint validation to the top level result object as a child
                 topLevelResult.addChild(constraintValidationResult);
                 trueCount += (constraintValidationResult.getStatus().getLevel() <= ErrorLevel.WARN.getLevel()) ? 1 : 0;
             }
         }
 
         List<MustOccurConstraint> mustOccurConstraints = constraint.getMustOccurConstraints();
         if (mustOccurConstraints != null) {
             for (MustOccurConstraint mustOccurConstraint : mustOccurConstraints) {
                 // Create a new constraint validation result for this must occur constraint and make it child of the top-level constraint,
                 // then pass it in to the recursive call so that prerequisite constraints can be placed under it
                 ConstraintValidationResult constraintValidationResult = new ConstraintValidationResult(CONSTRAINT_NAME);
                 constraintValidationResult.setConstraintLabelKey(mustOccurConstraint.getMessageKey());
                 constraintValidationResult.setErrorParameters(mustOccurConstraint.getValidationMessageParamsArray());
                 topLevelResult.addChild(constraintValidationResult);
                 trueCount += (processMustOccurConstraint(constraintValidationResult, mustOccurConstraint,
                         attributeValueReader)) ? 1 : 0;
             }
         }
 
         int minimum = constraint.getMin() != null ? constraint.getMin().intValue() : 0;
         int maximum = constraint.getMax() != null ? constraint.getMax().intValue() : 0;
 
         isSuccessful = (trueCount >= minimum && trueCount <= maximum) ? true : false;
 
         return isSuccessful;
     }
 
 }