/**
    * Copyright 2005-2011 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.kns.lookup;
  
  import org.apache.commons.beanutils.PropertyUtils;
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.encryption.EncryptionService;
  import org.kuali.rice.core.api.search.SearchOperator;
  import org.kuali.rice.krad.bo.BusinessObject;
  import org.kuali.rice.krad.bo.ExternalizableBusinessObject;
  import org.kuali.rice.krad.datadictionary.BusinessObjectEntry;
  import org.kuali.rice.krad.datadictionary.RelationshipDefinition;
  import org.kuali.rice.krad.service.KRADServiceLocatorWeb;
  import org.kuali.rice.krad.service.ModuleService;
  import org.kuali.rice.krad.util.BeanPropertyComparator;
  import org.kuali.rice.krad.util.ExternalizableBusinessObjectUtils;
  import org.kuali.rice.krad.util.KRADConstants;
  import org.kuali.rice.krad.util.ObjectUtils;
  import org.springframework.transaction.annotation.Transactional;
  
  import java.security.GeneralSecurityException;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  @Transactional
  public class KualiLookupableHelperServiceImpl extends AbstractLookupableHelperServiceImpl {
  
      protected static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(KualiLookupableHelperServiceImpl.class);
      protected boolean searchUsingOnlyPrimaryKeyValues = false;
  
  
      /**
       * Uses Lookup Service to provide a basic search.
       *
       * @param fieldValues - Map containing prop name keys and search values
       *
       * @return List found business objects
       * @see LookupableHelperService#getSearchResults(java.util.Map)
       */
      public List<? extends BusinessObject> getSearchResults(Map<String, String> fieldValues) {
          return getSearchResultsHelper(
                  org.kuali.rice.krad.lookup.LookupUtils.forceUppercase(getBusinessObjectClass(), fieldValues), false);
      }
  
  
      /**
       * Uses Lookup Service to provide a basic unbounded search.
       *
       * @param fieldValues - Map containing prop name keys and search values
       *
       * @return List found business objects
       * @see LookupableHelperService#getSearchResultsUnbounded(java.util.Map)
       */
      public List<? extends BusinessObject> getSearchResultsUnbounded(Map<String, String> fieldValues) {
          return getSearchResultsHelper(
                  org.kuali.rice.krad.lookup.LookupUtils.forceUppercase(getBusinessObjectClass(), fieldValues), true);
      }
  
      // TODO: Fix? - this does not handle nested properties within the EBO.
  
      /**
       * Check whether the given property represents a property within an EBO starting
       * with the sampleBo object given.  This is used to determine if a criteria needs
       * to be applied to the EBO first, before sending to the normal lookup DAO.
       */
      protected boolean isExternalBusinessObjectProperty(Object sampleBo, String propertyName) {
          try {
          	if ( propertyName.indexOf( "." ) > 0 && !StringUtils.contains( propertyName, "add." ) ) {
  	        	Class propertyClass = PropertyUtils.getPropertyType(
  						sampleBo, StringUtils.substringBeforeLast( propertyName, "." ) );
  	        	if ( propertyClass != null ) {
  	        		return ExternalizableBusinessObjectUtils.isExternalizableBusinessObjectInterface( propertyClass );
  	        	} else {
  	        		if ( LOG.isDebugEnabled() ) {
  	        			LOG.debug( "unable to get class for " + StringUtils.substringBeforeLast( propertyName, "." ) + " on " + sampleBo.getClass().getName() );
  	        		}
  	        	}
          	}
          } catch (Exception e) {
          	LOG.debug("Unable to determine type of property for " + sampleBo.getClass().getName() + "/" + propertyName, e );
         }
         return false;
     }
 
     /**
      * Get the name of the property which represents the ExternalizableBusinessObject for the given property.
      *
      * This method can not handle nested properties within the EBO.
      *
      * Returns null if the property is not a nested property or is part of an add line.
      */
     protected String getExternalBusinessObjectProperty(Object sampleBo, String propertyName) {
     	if ( propertyName.indexOf( "." ) > 0 && !StringUtils.contains( propertyName, "add." ) ) {
     		return StringUtils.substringBeforeLast( propertyName, "." );
     	}
         return null;
     }
 
     /**
      * Checks whether any of the fieldValues being passed refer to a property within an ExternalizableBusinessObject.
      */
     protected boolean hasExternalBusinessObjectProperty(Class boClass, Map<String,String> fieldValues ) {
     	try {
 	    	Object sampleBo = boClass.newInstance();
 	    	for ( String key : fieldValues.keySet() ) {
 	    		if ( isExternalBusinessObjectProperty( sampleBo, key )) {
 	    			return true;
 	    		}
 	    	}
     	} catch ( Exception ex ) {
         	LOG.debug("Unable to check " + boClass + " for EBO properties.", ex );
     	}
     	return false;
     }
 
     /**
      * Returns a map stripped of any properties which refer to ExternalizableBusinessObjects.  These values may not be passed into the
      * lookup service, since the objects they refer to are not in the local database.
      */
     protected Map<String,String> removeExternalizableBusinessObjectFieldValues(Class boClass, Map<String,String> fieldValues ) {
     	Map<String,String> eboFieldValues = new HashMap<String,String>();
     	try {
 	    	Object sampleBo = boClass.newInstance();
 	    	for ( String key : fieldValues.keySet() ) {
 	    		if ( !isExternalBusinessObjectProperty( sampleBo, key )) {
 	    			eboFieldValues.put( key, fieldValues.get( key ) );
 	    		}
 	    	}
     	} catch ( Exception ex ) {
         	LOG.debug("Unable to check " + boClass + " for EBO properties.", ex );
     	}
     	return eboFieldValues;
     }
 
     /**
      * Return the EBO fieldValue entries explicitly for the given eboPropertyName.  (I.e., any properties with the given
      * property name as a prefix.
      */
     protected Map<String,String> getExternalizableBusinessObjectFieldValues(String eboPropertyName, Map<String,String> fieldValues ) {
     	Map<String,String> eboFieldValues = new HashMap<String,String>();
     	for ( String key : fieldValues.keySet() ) {
     		if ( key.startsWith( eboPropertyName + "." ) ) {
     			eboFieldValues.put( StringUtils.substringAfterLast( key, "." ), fieldValues.get( key ) );
     		}
     	}
     	return eboFieldValues;
     }
 
     /**
      * Get the complete list of all properties referenced in the fieldValues that are ExternalizableBusinessObjects.
      *
      * This is a list of the EBO object references themselves, not of the properties within them.
      */
     protected List<String> getExternalizableBusinessObjectProperties(Class boClass, Map<String,String> fieldValues ) {
     	Set<String> eboPropertyNames = new HashSet<String>();
     	try {
 	    	Object sampleBo = boClass.newInstance();
 	    	for ( String key : fieldValues.keySet() ) {
 	    		if ( isExternalBusinessObjectProperty( sampleBo, key )) {
 	    			eboPropertyNames.add( StringUtils.substringBeforeLast( key, "." ) );
 	    		}
 	    	}
     	} catch ( Exception ex ) {
         	LOG.debug("Unable to check " + boClass + " for EBO properties.", ex );
     	}
     	return new ArrayList<String>(eboPropertyNames);
     }
 
     /**
      * Given an property on the main BO class, return the defined type of the ExternalizableBusinessObject.  This will be used
      * by other code to determine the correct module service to call for the lookup.
      *
      * @param boClass
      * @param propertyName
      * @return
      */
     protected Class<? extends ExternalizableBusinessObject> getExternalizableBusinessObjectClass(Class boClass, String propertyName) {
         try {
         	return PropertyUtils.getPropertyType(
 					boClass.newInstance(), StringUtils.substringBeforeLast( propertyName, "." ) );
         } catch (Exception e) {
         	LOG.debug("Unable to determine type of property for " + boClass.getName() + "/" + propertyName, e );
         }
         return null;
     }
 
     /**
      *
      * This method does the actual search, with the parameters specified, and returns the result.
      *
      * NOTE that it will not do any upper-casing based on the DD forceUppercase. That is handled through an external call to
      * LookupUtils.forceUppercase().
      *
      * @param fieldValues A Map of the fieldNames and fieldValues to be searched on.
      * @param unbounded Whether the results should be bounded or not to a certain max size.
      * @return A List of search results.
      *
      */
     protected List<? extends BusinessObject> getSearchResultsHelper(Map<String, String> fieldValues, boolean unbounded) {
         // remove hidden fields
         LookupUtils.removeHiddenCriteriaFields(getBusinessObjectClass(), fieldValues);
 
         searchUsingOnlyPrimaryKeyValues = getLookupService().allPrimaryKeyValuesPresentAndNotWildcard(getBusinessObjectClass(), fieldValues);
 
         setBackLocation(fieldValues.get(KRADConstants.BACK_LOCATION));
         setDocFormKey(fieldValues.get(KRADConstants.DOC_FORM_KEY));
         setReferencesToRefresh(fieldValues.get(KRADConstants.REFERENCES_TO_REFRESH));
         List searchResults;
     	Map<String,String> nonBlankFieldValues = new HashMap<String, String>();
     	for (String fieldName : fieldValues.keySet()) {
     		String fieldValue = fieldValues.get(fieldName);
     		if (StringUtils.isNotBlank(fieldValue) ) {
     			if (fieldValue.endsWith(EncryptionService.ENCRYPTION_POST_PREFIX)) {
     				String encryptedValue = StringUtils.removeEnd(fieldValue, EncryptionService.ENCRYPTION_POST_PREFIX);
     				try {
     					fieldValue = getEncryptionService().decrypt(encryptedValue);
     				}
     				catch (GeneralSecurityException e) {
             			LOG.error("Error decrypting value for business object " + getBusinessObjectService() + " attribute " + fieldName, e);
             			throw new RuntimeException("Error decrypting value for business object " + getBusinessObjectService() + " attribute " + fieldName, e);
             		}
     			}
     			nonBlankFieldValues.put(fieldName, fieldValue);
     		}
     	}
 
         // If this class is an EBO, just call the module service to get the results
         if ( ExternalizableBusinessObject.class.isAssignableFrom( getBusinessObjectClass() ) ) {
         	ModuleService eboModuleService = KRADServiceLocatorWeb.getKualiModuleService().getResponsibleModuleService( getBusinessObjectClass() );
         	BusinessObjectEntry ddEntry = eboModuleService.getExternalizableBusinessObjectDictionaryEntry(getBusinessObjectClass());
         	Map<String,String> filteredFieldValues = new HashMap<String, String>();
         	for (String fieldName : nonBlankFieldValues.keySet()) {
         		if (ddEntry.getAttributeNames().contains(fieldName)) {
         			filteredFieldValues.put(fieldName, nonBlankFieldValues.get(fieldName));
         		}
         	}
         	searchResults = eboModuleService.getExternalizableBusinessObjectsListForLookup(getBusinessObjectClass(), (Map)filteredFieldValues, unbounded);
         // if any of the properties refer to an embedded EBO, call the EBO lookups first and apply to the local lookup
         } else if ( hasExternalBusinessObjectProperty( getBusinessObjectClass(), nonBlankFieldValues ) ) {
         	if ( LOG.isDebugEnabled() ) {
         		LOG.debug( "has EBO reference: " + getBusinessObjectClass() );
         		LOG.debug( "properties: " + nonBlankFieldValues );
         	}
         	// remove the EBO criteria
         	Map<String,String> nonEboFieldValues = removeExternalizableBusinessObjectFieldValues( getBusinessObjectClass(), nonBlankFieldValues );
         	if ( LOG.isDebugEnabled() ) {
         		LOG.debug( "Non EBO properties removed: " + nonEboFieldValues );
         	}
         	// get the list of EBO properties attached to this object
         	List<String> eboPropertyNames = getExternalizableBusinessObjectProperties( getBusinessObjectClass(), nonBlankFieldValues );
         	if ( LOG.isDebugEnabled() ) {
         		LOG.debug( "EBO properties: " + eboPropertyNames );
         	}
         	// loop over those properties
         	for ( String eboPropertyName : eboPropertyNames ) {
         		// extract the properties as known to the EBO
         		Map<String,String> eboFieldValues = getExternalizableBusinessObjectFieldValues( eboPropertyName, nonBlankFieldValues );
             	if ( LOG.isDebugEnabled() ) {
             		LOG.debug( "EBO properties for master EBO property: " + eboPropertyName );
             		LOG.debug( "properties: " + eboFieldValues );
             	}
             	// run search against attached EBO's module service
             	ModuleService eboModuleService = KRADServiceLocatorWeb.getKualiModuleService().getResponsibleModuleService( getExternalizableBusinessObjectClass( getBusinessObjectClass(), eboPropertyName) );
             	// KULRICE-4401 made eboResults an empty list and only filled if service is found.
          	 	List eboResults = Collections.emptyList();
          	 	if (eboModuleService != null) 
          	 	{
          	 		eboResults = eboModuleService.getExternalizableBusinessObjectsListForLookup( getExternalizableBusinessObjectClass( getBusinessObjectClass(), eboPropertyName), (Map)eboFieldValues, unbounded);
          	 	}
          	 		else
          	 	{
          	 		LOG.debug( "EBO ModuleService is null: " + eboPropertyName );
          	 	}
         		// get the mapping/relationship between the EBO object and it's parent object
         		// use that to adjust the fieldValues
 
         		// get the parent property type
         		Class eboParentClass;
         		String eboParentPropertyName;
         		if ( ObjectUtils.isNestedAttribute( eboPropertyName ) ) {
         			eboParentPropertyName = StringUtils.substringBeforeLast( eboPropertyName, "." );
 	        		try {
 	        			eboParentClass = PropertyUtils.getPropertyType( getBusinessObjectClass().newInstance(), eboParentPropertyName );
 	        		} catch ( Exception ex ) {
 	        			throw new RuntimeException( "Unable to create an instance of the business object class: " + getBusinessObjectClass().getName(), ex );
 	        		}
         		} else {
         			eboParentClass = getBusinessObjectClass();
         			eboParentPropertyName = null;
         		}
         		if ( LOG.isDebugEnabled() ) {
         			LOG.debug( "determined EBO parent class/property name: " + eboParentClass + "/" + eboParentPropertyName );
         		}
         		// look that up in the DD (BOMDS)
         		// find the appropriate relationship
         		// CHECK THIS: what if eboPropertyName is a nested attribute - need to strip off the eboParentPropertyName if not null
         		RelationshipDefinition rd = getBusinessObjectMetaDataService().getBusinessObjectRelationshipDefinition( eboParentClass, eboPropertyName );
         		if ( LOG.isDebugEnabled() ) {
         			LOG.debug( "Obtained RelationshipDefinition for " + eboPropertyName );
         			LOG.debug( rd );
         		}
 
         		// copy the needed properties (primary only) to the field values
         		// KULRICE-4446 do so only if the relationship definition exists
         		// NOTE: this will work only for single-field PK unless the ORM layer is directly involved
         		// (can't make (field1,field2) in ( (v1,v2),(v3,v4) ) style queries in the lookup framework
         		if ( ObjectUtils.isNotNull(rd)) {
 	        		if ( rd.getPrimitiveAttributes().size() > 1 ) {
 	        			throw new RuntimeException( "EBO Links don't work for relationships with multiple-field primary keys." );
 	        		}
 	        		String boProperty = rd.getPrimitiveAttributes().get( 0 ).getSourceName();
 	        		String eboProperty = rd.getPrimitiveAttributes().get( 0 ).getTargetName();
 	        		StringBuffer boPropertyValue = new StringBuffer();
 	        		// loop over the results, making a string that the lookup DAO will convert into an
 	        		// SQL "IN" clause
 	        		for ( Object ebo : eboResults ) {
 	        			if ( boPropertyValue.length() != 0 ) {
 	        				boPropertyValue.append( SearchOperator.OR.op() );
 	        			}
 	        			try {
 	        				boPropertyValue.append( PropertyUtils.getProperty( ebo, eboProperty ).toString() );
 	        			} catch ( Exception ex ) {
 	        				LOG.warn( "Unable to get value for " + eboProperty + " on " + ebo );
 	        			}
 	        		}
 	        		if ( eboParentPropertyName == null ) {
 	        			// non-nested property containing the EBO
 	        			nonEboFieldValues.put( boProperty, boPropertyValue.toString() );
 	        		} else {
 	        			// property nested within the main searched-for BO that contains the EBO
 	        			nonEboFieldValues.put( eboParentPropertyName + "." + boProperty, boPropertyValue.toString() );
 	        		}
         		}
         	}
         	if ( LOG.isDebugEnabled() ) {
         		LOG.debug( "Passing these results into the lookup service: " + nonEboFieldValues );
         	}
         	// add those results as criteria
         	// run the normal search (but with the EBO critieria added)
     		searchResults = (List) getLookupService().findCollectionBySearchHelper(getBusinessObjectClass(), nonEboFieldValues, unbounded);
         } else {
             searchResults = (List) getLookupService().findCollectionBySearchHelper(getBusinessObjectClass(), nonBlankFieldValues, unbounded);
         }
         
         if (searchResults == null) {
         	searchResults = new ArrayList();
         }
 
         // sort list if default sort column given
         List defaultSortColumns = getDefaultSortColumns();
         if (defaultSortColumns.size() > 0) {
             Collections.sort(searchResults, new BeanPropertyComparator(defaultSortColumns, true));
         }
         return searchResults;
     }
 
 
     /**
      * @see LookupableHelperService#isSearchUsingOnlyPrimaryKeyValues()
      */
     @Override
     public boolean isSearchUsingOnlyPrimaryKeyValues() {
         return searchUsingOnlyPrimaryKeyValues;
 }
 
 
     /**
      * Returns a comma delimited list of primary key field labels, to be used on the UI to tell the user which fields were used to search
      *
      * These labels are generated from the DD definitions for the lookup fields
      *
      * @return a comma separated list of field attribute names.  If no fields found, returns "N/A"
      * @see LookupableHelperService#isSearchUsingOnlyPrimaryKeyValues()
      * @see LookupableHelperService#getPrimaryKeyFieldLabels()
      */
     @Override
     public String getPrimaryKeyFieldLabels() {
         StringBuilder buf = new StringBuilder();
         List<String> primaryKeyFieldNames = getBusinessObjectMetaDataService().listPrimaryKeyFieldNames(getBusinessObjectClass());
         Iterator<String> pkIter = primaryKeyFieldNames.iterator();
         while (pkIter.hasNext()) {
             String pkFieldName = (String) pkIter.next();
             buf.append(getDataDictionaryService().getAttributeLabel(getBusinessObjectClass(), pkFieldName));
             if (pkIter.hasNext()) {
                 buf.append(", ");
             }
         }
         return buf.length() == 0 ? KRADConstants.NOT_AVAILABLE_STRING : buf.toString();
     }
 
 
 }