/**
    * 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.krms.impl.ui;
  
  
  import org.apache.commons.collections.CollectionUtils;
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.util.ConcreteKeyValue;
  import org.kuali.rice.core.api.util.KeyValue;
  import org.kuali.rice.krad.service.KRADServiceLocator;
  import org.kuali.rice.krad.uif.control.UifKeyValuesFinderBase;
  import org.kuali.rice.krad.uif.view.ViewModel;
  import org.kuali.rice.krad.web.form.MaintenanceForm;
  import org.kuali.rice.krms.impl.repository.CategoryBo;
  import org.kuali.rice.krms.impl.repository.ContextValidTermBo;
  import org.kuali.rice.krms.impl.repository.PropositionBo;
  import org.kuali.rice.krms.impl.repository.TermBo;
  import org.kuali.rice.krms.impl.repository.TermResolverBo;
  import org.kuali.rice.krms.impl.repository.TermSpecificationBo;
  import org.kuali.rice.krms.impl.util.KrmsImplConstants;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.List;
  
  /**
   * ValuesFinder used to populate the list of available Terms when creating/editing a proposition in a
   * KRMS Rule.
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class ValidTermsValuesFinder extends UifKeyValuesFinderBase {
  
      /**
       * get the value list for the Term dropdown in the KRMS rule editing UI
       * @param model
       * @return
       */
      @Override
      public List<KeyValue> getKeyValues(ViewModel model) {
          List<KeyValue> keyValues = new ArrayList<KeyValue>();
  
          MaintenanceForm maintenanceForm = (MaintenanceForm) model;
          AgendaEditor agendaEditor = ((AgendaEditor) maintenanceForm.getDocument().getNewMaintainableObject().getDataObject());
          String contextId = agendaEditor.getAgenda().getContextId();
  
          String selectedPropId = agendaEditor.getSelectedPropositionId();
  
          PropositionBo rootProposition = agendaEditor.getAgendaItemLine().getRule().getProposition();
          PropositionBo editModeProposition = findPropositionUnderEdit(rootProposition);
          String selectedCategoryId = (editModeProposition != null) ? editModeProposition.getCategoryId() : null;
  
          // Get all valid terms
  
          Collection<ContextValidTermBo> contextValidTerms = null;
          contextValidTerms = KRADServiceLocator.getBusinessObjectService()
                  .findMatching(ContextValidTermBo.class, Collections.singletonMap("contextId", contextId));
  
          List<String> termSpecIds = new ArrayList();
          for (ContextValidTermBo validTerm : contextValidTerms) {
              termSpecIds.add(validTerm.getTermSpecificationId());
          }
  
          if (termSpecIds.size() > 0) { // if we don't have any valid terms, skip it
              Collection<TermBo> terms = null;
              Map<String,Object> criteria = new HashMap<String,Object>();
              criteria.put("specificationId", termSpecIds);
              terms = KRADServiceLocator.getBusinessObjectService().findMatchingOrderBy(TermBo.class, criteria, "description", true);
  
              // add all terms that are in the selected category (or else add 'em all if no category is selected)
              for (TermBo term : terms) {
                  String selectName = term.getDescription();
  
                  if (StringUtils.isBlank(selectName) || "null".equals(selectName)) {
                      selectName = term.getSpecification().getName();
                  }
  
                  if (!StringUtils.isBlank(selectedCategoryId)) {
                      // only add if the term has the selected category
                      if (isTermSpecificationInCategory(term.getSpecification(), selectedCategoryId)) {
                          keyValues.add(new ConcreteKeyValue(term.getId(), selectName));
                      }
                  } else {
                     keyValues.add(new ConcreteKeyValue(term.getId(), selectName));
                 }
             }
 
             //
             // Add Parameterized Term Specs
             //
 
             // get term resolvers for the given term specs
             Collection<TermResolverBo> termResolvers =
                     KRADServiceLocator.getBusinessObjectService().findMatchingOrderBy(
                             TermResolverBo.class, Collections.singletonMap("outputId", termSpecIds), "name", true
                     );
 
             // TODO: what if there is more than one resolver for a given term specification?
 
             if (termResolvers != null) for (TermResolverBo termResolver : termResolvers) {
                 if (!CollectionUtils.isEmpty(termResolver.getParameterSpecifications())) {
                     TermSpecificationBo output = termResolver.getOutput();
 
                     // filter by category
                     if (StringUtils.isBlank(selectedCategoryId) ||
                             isTermSpecificationInCategory(output, selectedCategoryId)) {
                     	String outputDescription = StringUtils.isBlank(output.getDescription())?output.getName():
                     																			output.getDescription();
                         // we use a special prefix to differentiate these, as they are term spec ids instead of term ids.
                         keyValues.add(new ConcreteKeyValue(KrmsImplConstants.PARAMETERIZED_TERM_PREFIX
                                 + output.getId(), outputDescription
                                 // build a string that indicates the number of parameters
                                 + "(" + StringUtils.repeat("_", ",", termResolver.getParameterSpecifications().size()) +")"));
                     }
                 }
             }
         }
 
         return keyValues;
     }
 
     /**
      * @return true if the term specification is in the given category
      */
     private boolean isTermSpecificationInCategory(TermSpecificationBo termSpec, String categoryId) {
         if (termSpec.getCategories() != null) {
             for (CategoryBo category : termSpec.getCategories()) {
                 if (categoryId.equals(category.getId())) {
                     return true;
                 }
             }
         }
         return false;
     }
 
     /**
      * helper method to find the proposition under edit
      */
     private PropositionBo findPropositionUnderEdit(PropositionBo currentProposition) {
         PropositionBo result = null;
         if (currentProposition.getEditMode()) {
             result = currentProposition;
         } else {
             if (currentProposition.getCompoundComponents() != null) {
                 for (PropositionBo child : currentProposition.getCompoundComponents()) {
                     result = findPropositionUnderEdit(child);
                     if (result != null) break;
                 }
             }
         }
         return result;
     }
 
 }