/*

  * Copyright 2005-2007 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.datadictionary;

 import java.beans.IntrospectionException;

 import java.beans.PropertyDescriptor;

 import java.io.File;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 import java.util.TreeMap;

 import org.apache.commons.lang.StringUtils;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.kuali.rice.core.util.ClassLoaderUtils;

 import org.kuali.rice.kns.bo.BusinessObject;

 import org.kuali.rice.kns.bo.PersistableBusinessObjectExtension;

 import org.kuali.rice.kns.datadictionary.exception.AttributeValidationException;

 import org.kuali.rice.kns.datadictionary.exception.CompletionException;

 import org.kuali.rice.kns.service.KNSServiceLocator;

 import org.kuali.rice.kns.service.ModuleService;

 import org.kuali.rice.kns.service.PersistenceStructureService;

 import org.kuali.rice.kns.util.ObjectUtils;

 import org.springframework.beans.factory.support.DefaultListableBeanFactory;

 import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;

 import org.springframework.core.io.DefaultResourceLoader;

 import org.springframework.core.io.Resource;

 /**

  * Collection of named BusinessObjectEntry objects, each of which contains

  * information relating to the display, validation, and general maintenance of a

  * BusinessObject.

  * 

  * 

  */

 public class DataDictionary {

     private DefaultListableBeanFactory ddBeans = new DefaultListableBeanFactory();

     private XmlBeanDefinitionReader xmlReader = new XmlBeanDefinitionReader(ddBeans);

         // logger

         private static final Log LOG = LogFactory.getLog(DataDictionary.class);

         /**

          * The encapsulation of DataDictionary indices

          */

         private DataDictionaryIndex ddIndex = new DataDictionaryIndex(ddBeans);

         /**

          * The DataDictionaryMapper

          * The default mapper simply consults the initialized indices

          * on workflow document type

          */

         private DataDictionaryMapper ddMapper = new DataDictionaryIndexMapper();

         private List<String> configFileLocations = new ArrayList<String>();

     public DataDictionary() { }

         public List<String> getConfigFileLocations() {

         return this.configFileLocations;

     }

     public void setConfigFileLocations(List<String> configFileLocations) {

         this.configFileLocations = configFileLocations;

     }

     public void addConfigFileLocation( String location ) throws IOException {

         indexSource( location );

     }

     /**

      * Sets the DataDictionaryMapper

      * @param mapper the datadictionary mapper

      */

     public void setDataDictionaryMapper(DataDictionaryMapper mapper) {

             this.ddMapper = mapper;

     }

     private void indexSource(String sourceName) throws IOException {        

         if (sourceName == null) {

             throw new DataDictionaryException("Source Name given is null");

         }

         if (!sourceName.endsWith(".xml") ) {

             Resource resource = getFileResource(sourceName);

             if (resource.exists()) {

                 indexSource(resource.getFile());

             } else {

                 LOG.warn("Could not find " + sourceName);

                 throw new DataDictionaryException("DD Resource " + sourceName + " not found");

             }

         } else {

             if ( LOG.isDebugEnabled() ) {

                 LOG.debug("adding sourceName " + sourceName + " ");

             }

             Resource resource = getFileResource(sourceName);

             if (! resource.exists()) {

                 throw new DataDictionaryException("DD Resource " + sourceName + " not found");  

             }

             String indexName = sourceName.substring(sourceName.lastIndexOf("/") + 1, sourceName.indexOf(".xml"));

             configFileLocations.add( sourceName );

         }

     }    

     private Resource getFileResource(String sourceName) {

         DefaultResourceLoader resourceLoader = new DefaultResourceLoader(ClassLoaderUtils.getDefaultClassLoader());

         return resourceLoader.getResource(sourceName);

     }

     private void indexSource(File dir) {

         for (File file : dir.listFiles()) {

             if (file.isDirectory()) {

                 indexSource(file);

             } else if (file.getName().endsWith(".xml") ) {

                 configFileLocations.add( "file:" + file.getAbsolutePath());

             } else {

                 if ( LOG.isDebugEnabled() ) {

                     LOG.debug("Skipping non xml file " + file.getAbsolutePath() + " in DD load");

                 }

             }

         }

     }

     public void parseDataDictionaryConfigurationFiles( boolean allowConcurrentValidation ) {

         // expand configuration locations into files

         LOG.info( "Starting DD XML File Load" );

         String[] configFileLocationsArray = new String[configFileLocations.size()];

         configFileLocationsArray = configFileLocations.toArray( configFileLocationsArray );

         configFileLocations.clear(); // empty the list out so other items can be added

         try {

             xmlReader.loadBeanDefinitions( configFileLocationsArray );

         } catch (Exception e) {

             LOG.error("Error loading bean definitions", e);

             throw new DataDictionaryException("Error loading bean definitions: " + e.getLocalizedMessage());

         }

         LOG.info( "Completed DD XML File Load" );

         if ( allowConcurrentValidation ) {

             Thread t = new Thread(ddIndex);

             t.start();

         } else {

             ddIndex.run();

         }

     }

     static boolean validateEBOs = true;

     public void validateDD( boolean validateEbos ) {

             DataDictionary.validateEBOs = validateEbos;

         Map<String,BusinessObjectEntry> boBeans = ddBeans.getBeansOfType(BusinessObjectEntry.class);

         for ( BusinessObjectEntry entry : boBeans.values() ) {

             entry.completeValidation();

         }

         Map<String,DocumentEntry> docBeans = ddBeans.getBeansOfType(DocumentEntry.class);

         for ( DocumentEntry entry : docBeans.values() ) {

             entry.completeValidation();

         }

     }

     public void validateDD() {

             DataDictionary.validateEBOs = true;

         Map<String,BusinessObjectEntry> boBeans = ddBeans.getBeansOfType(BusinessObjectEntry.class);

         for ( BusinessObjectEntry entry : boBeans.values() ) {

             entry.completeValidation();

         }

         Map<String,DocumentEntry> docBeans = ddBeans.getBeansOfType(DocumentEntry.class);

         for ( DocumentEntry entry : docBeans.values() ) {

             entry.completeValidation();

         }

     }

         /**

          * @param className

          * @return BusinessObjectEntry for the named class, or null if none exists

          */

         public BusinessObjectEntry getBusinessObjectEntry(String className ) {

                 return ddMapper.getBusinessObjectEntry(ddIndex, className);

         }

         /**

          * This method gets the business object entry for a concrete class

          * 

          * @param className

          * @return

          */

         public BusinessObjectEntry getBusinessObjectEntryForConcreteClass(String className){

                 return ddMapper.getBusinessObjectEntryForConcreteClass(ddIndex, className);

         }

         /**

          * @return List of businessObject classnames

          */

         public List<String> getBusinessObjectClassNames() {

                 return ddMapper.getBusinessObjectClassNames(ddIndex);

         }

         /**

          * @return Map of (classname, BusinessObjectEntry) pairs

          */

         public Map<String, BusinessObjectEntry> getBusinessObjectEntries() {

                 return ddMapper.getBusinessObjectEntries(ddIndex);

         }

         /**

          * @param className

          * @return DataDictionaryEntryBase for the named class, or null if none

          *         exists

          */

         public DataDictionaryEntry getDictionaryObjectEntry(String className) {

                 return ddMapper.getDictionaryObjectEntry(ddIndex, className);

         }

         /**

          * Returns the KNS document entry for the given lookup key.  The documentTypeDDKey is interpreted

          * successively in the following ways until a mapping is found (or none if found):

          * <ol>

          * <li>KEW/workflow document type</li>

          * <li>business object class name</li>

          * <li>maintainable class name</li>

          * </ol>

          * This mapping is compiled when DataDictionary files are parsed on startup (or demand).  Currently this

          * means the mapping is static, and one-to-one (one KNS document maps directly to one and only

          * one key).

          * 

          * @param documentTypeDDKey the KEW/workflow document type name

          * @return the KNS DocumentEntry if it exists

          */

         public DocumentEntry getDocumentEntry(String documentTypeDDKey ) {

                 return ddMapper.getDocumentEntry(ddIndex, documentTypeDDKey);

         }

         /**

          * Note: only MaintenanceDocuments are indexed by businessObject Class

          * 

          * This is a special case that is referenced in one location. Do we need

          * another map for this stuff??

          * 

          * @param businessObjectClass

          * @return DocumentEntry associated with the given Class, or null if there

          *         is none

          */

         public MaintenanceDocumentEntry getMaintenanceDocumentEntryForBusinessObjectClass(Class businessObjectClass) {

                 return ddMapper.getMaintenanceDocumentEntryForBusinessObjectClass(ddIndex, businessObjectClass);

         }

         public Map<String, DocumentEntry> getDocumentEntries() {

                 return ddMapper.getDocumentEntries(ddIndex);

         }

     /**

      * @param clazz

      * @param propertyName

      * @return true if the given propertyName names a property of the given class

      * @throws CompletionException if there is a problem accessing the named property on the given class

      */

     public static boolean isPropertyOf(Class targetClass, String propertyName) {

         if (targetClass == null) {

             throw new IllegalArgumentException("invalid (null) targetClass");

         }

         if (StringUtils.isBlank(propertyName)) {

             throw new IllegalArgumentException("invalid (blank) propertyName");

         }

         PropertyDescriptor propertyDescriptor = buildReadDescriptor(targetClass, propertyName);

         boolean isPropertyOf = (propertyDescriptor != null);

         return isPropertyOf;

     }

     /**

      * @param clazz

      * @param propertyName

      * @return true if the given propertyName names a Collection property of the given class

      * @throws CompletionException if there is a problem accessing the named property on the given class

      */

     public static boolean isCollectionPropertyOf(Class targetClass, String propertyName) {

         boolean isCollectionPropertyOf = false;

         PropertyDescriptor propertyDescriptor = buildReadDescriptor(targetClass, propertyName);

         if (propertyDescriptor != null) {

             Class clazz = propertyDescriptor.getPropertyType();

             if ((clazz != null) && Collection.class.isAssignableFrom(clazz)) {

                 isCollectionPropertyOf = true;

             }

         }

         return isCollectionPropertyOf;

     }

     public static PersistenceStructureService persistenceStructureService;

     /**

      * @return the persistenceStructureService

      */

     public static PersistenceStructureService getPersistenceStructureService() {

         if ( persistenceStructureService == null ) {

             persistenceStructureService = KNSServiceLocator.getPersistenceStructureService();

         }

         return persistenceStructureService;

     }

     /**

      * This method determines the Class of the attributeName passed in. Null will be returned if the member is not available, or if

      * a reflection exception is thrown.

      * 

      * @param rootClass - Class that the attributeName property exists in.

      * @param attributeName - Name of the attribute you want a class for.

      * @return The Class of the attributeName, if the attribute exists on the rootClass. Null otherwise.

      */

     public static Class getAttributeClass(Class boClass, String attributeName) {

         // fail loudly if the attributeName isnt a member of rootClass

         if (!isPropertyOf(boClass, attributeName)) {

             throw new AttributeValidationException("unable to find attribute '" + attributeName + "' in rootClass '" + boClass.getName() + "'");

         }

             //Implementing Externalizable Business Object Services...

         //The boClass can be an interface, hence handling this separately, 

         //since the original method was throwing exception if the class could not be instantiated.

         if(boClass.isInterface())

                 return getAttributeClassWhenBOIsInterface(boClass, attributeName);

         else

                 return getAttributeClassWhenBOIsClass(boClass, attributeName);                

     }

     /**

      * 

      * This method gets the property type of the given attributeName when the bo class is a concrete class

      * 

      * @param boClass

      * @param attributeName

      * @return

      */

     private static Class getAttributeClassWhenBOIsClass(Class boClass, String attributeName){

             BusinessObject boInstance;

         try {

             boInstance = (BusinessObject) boClass.newInstance();

         } catch (Exception e) {

                 throw new RuntimeException("Unable to instantiate BO: " + boClass, e);

         }

         // attempt to retrieve the class of the property

         try {

             return ObjectUtils.getPropertyType(boInstance, attributeName, getPersistenceStructureService());

         } catch (Exception e) {

             throw new RuntimeException("Unable to determine property type for: " + boClass.getName() + "." + attributeName, e);

         }

     }

     /**

      * 

      * This method gets the property type of the given attributeName when the bo class is an interface

      * This method will also work if the bo class is not an interface, 

      * but that case requires special handling, hence a separate method getAttributeClassWhenBOIsClass 

      * 

      * @param boClass

      * @param attributeName

      * @return

      */

     private static Class getAttributeClassWhenBOIsInterface(Class boClass, String attributeName){

         if (boClass == null) {

             throw new IllegalArgumentException("invalid (null) boClass");

         }

         if (StringUtils.isBlank(attributeName)) {

             throw new IllegalArgumentException("invalid (blank) attributeName");

         }

         PropertyDescriptor propertyDescriptor = null;

         String[] intermediateProperties = attributeName.split("\\.");

         int lastLevel = intermediateProperties.length - 1;

         Class currentClass = boClass;

         for (int i = 0; i <= lastLevel; ++i) {

             String currentPropertyName = intermediateProperties[i];

             propertyDescriptor = buildSimpleReadDescriptor(currentClass, currentPropertyName);

             if (propertyDescriptor != null) {

                 Class propertyType = propertyDescriptor.getPropertyType();

                 if ( propertyType.equals( PersistableBusinessObjectExtension.class ) ) {

                     propertyType = getPersistenceStructureService().getBusinessObjectAttributeClass( currentClass, currentPropertyName );                    

                 }

                 if (Collection.class.isAssignableFrom(propertyType)) {

                         // TODO: determine property type using generics type definition

                         throw new AttributeValidationException("Can't determine the Class of Collection elements because when the business object is an (possibly ExternalizableBusinessObject) interface.");

                 }

                 else {

                     currentClass = propertyType;

                 }

             }

             else {

                     throw new AttributeValidationException("Can't find getter method of " + boClass.getName() + " for property " + attributeName);

             }

         }

         return currentClass;

     }

     /**

      * This method determines the Class of the elements in the collectionName passed in.

      * 

      * @param boClass Class that the collectionName collection exists in.

      * @param collectionName the name of the collection you want the element class for

      * @return

      */

     public static Class getCollectionElementClass(Class boClass, String collectionName) {

         if (boClass == null) {

             throw new IllegalArgumentException("invalid (null) boClass");

         }

         if (StringUtils.isBlank(collectionName)) {

             throw new IllegalArgumentException("invalid (blank) collectionName");

         }

         PropertyDescriptor propertyDescriptor = null;

         String[] intermediateProperties = collectionName.split("\\.");

         Class currentClass = boClass;

         for (int i = 0; i <intermediateProperties.length; ++i) {

             String currentPropertyName = intermediateProperties[i];

             propertyDescriptor = buildSimpleReadDescriptor(currentClass, currentPropertyName);

                 if (propertyDescriptor != null) {

                     Class type = propertyDescriptor.getPropertyType();

                     if (Collection.class.isAssignableFrom(type)) {

                         if (getPersistenceStructureService().isPersistable(currentClass)) {

                             Map<String, Class> collectionClasses = new HashMap<String, Class>();

                             collectionClasses = getPersistenceStructureService().listCollectionObjectTypes(currentClass);

                             currentClass = collectionClasses.get(currentPropertyName);

                         }

                         else {

                             throw new RuntimeException("Can't determine the Class of Collection elements because persistenceStructureService.isPersistable(" + currentClass.getName() + ") returns false.");

                         }

                     }

                     else {

                         currentClass = propertyDescriptor.getPropertyType();

                     }

                 }

             }

         return currentClass;

     }

     static private Map<String, Map<String, PropertyDescriptor>> cache = new TreeMap<String, Map<String, PropertyDescriptor>>();

     /**

      * @param propertyClass

      * @param propertyName

      * @return PropertyDescriptor for the getter for the named property of the given class, if one exists.

      */

     public static PropertyDescriptor buildReadDescriptor(Class propertyClass, String propertyName) {

         if (propertyClass == null) {

             throw new IllegalArgumentException("invalid (null) propertyClass");

         }

         if (StringUtils.isBlank(propertyName)) {

             throw new IllegalArgumentException("invalid (blank) propertyName");

         }

         PropertyDescriptor propertyDescriptor = null;

         String[] intermediateProperties = propertyName.split("\\.");

         int lastLevel = intermediateProperties.length - 1;

         Class currentClass = propertyClass;

         for (int i = 0; i <= lastLevel; ++i) {

             String currentPropertyName = intermediateProperties[i];

             propertyDescriptor = buildSimpleReadDescriptor(currentClass, currentPropertyName);

             if (i < lastLevel) {

                 if (propertyDescriptor != null) {

                     Class propertyType = propertyDescriptor.getPropertyType();

                     if ( propertyType.equals( PersistableBusinessObjectExtension.class ) ) {

                         propertyType = getPersistenceStructureService().getBusinessObjectAttributeClass( currentClass, currentPropertyName );                    

                     }

                     if (Collection.class.isAssignableFrom(propertyType)) {

                         if (getPersistenceStructureService().isPersistable(currentClass)) {

                             Map<String, Class> collectionClasses = new HashMap<String, Class>();

                             collectionClasses = getPersistenceStructureService().listCollectionObjectTypes(currentClass);

                             currentClass = collectionClasses.get(currentPropertyName);

                         }

                         else {

                             throw new RuntimeException("Can't determine the Class of Collection elements because persistenceStructureService.isPersistable(" + currentClass.getName() + ") returns false.");

                         }

                     }

                     else {

                         currentClass = propertyType;

                     }

                 }

             }

         }

         return propertyDescriptor;

     }

     /**

      * @param propertyClass

      * @param propertyName

      * @return PropertyDescriptor for the getter for the named property of the given class, if one exists.

      */

     public static PropertyDescriptor buildSimpleReadDescriptor(Class propertyClass, String propertyName) {

         if (propertyClass == null) {

             throw new IllegalArgumentException("invalid (null) propertyClass");

         }

         if (StringUtils.isBlank(propertyName)) {

             throw new IllegalArgumentException("invalid (blank) propertyName");

         }

         PropertyDescriptor p = null;

         // check to see if we've cached this descriptor already. if yes, return true.

         String propertyClassName = propertyClass.getName();

         Map<String, PropertyDescriptor> m = cache.get(propertyClassName);

         if (null != m) {

             p = m.get(propertyName);

             if (null != p) {

                 return p;

             }

         }

         String prefix = StringUtils.capitalize(propertyName);

         String getName = "get" + prefix;

         String isName = "is" + prefix;

         try {

             p = new PropertyDescriptor(propertyName, propertyClass, getName, null);

         }

         catch (IntrospectionException e) {

             try {

                 p = new PropertyDescriptor(propertyName, propertyClass, isName, null);

             }

             catch (IntrospectionException f) {

                 // ignore it

             }

         }

         // cache the property descriptor if we found it.

         if (null != p) {

             if (null == m) {

                 m = new TreeMap<String, PropertyDescriptor>();

                 cache.put(propertyClassName, m);

             }

             m.put(propertyName, p);

         }

         return p;

     }

     public Set<InactivationBlockingMetadata> getAllInactivationBlockingMetadatas(Class blockedClass) {

             return ddMapper.getAllInactivationBlockingMetadatas(ddIndex, blockedClass);

     }

     /**

      * This method gathers beans of type BeanOverride and invokes each one's performOverride() method.

      */

     // KULRICE-4513

     public void performBeanOverrides()

     {

             Collection<BeanOverride> beanOverrides = ddBeans.getBeansOfType(BeanOverride.class).values();

             if (beanOverrides.isEmpty()){

                     LOG.info("DataDictionary.performOverrides(): No beans to override");

             }

                 for (BeanOverride beanOverride : beanOverrides) {

                         Object bean = ddBeans.getBean(beanOverride.getBeanName());

                         beanOverride.performOverride(bean);

                         LOG.info("DataDictionary.performOverrides(): Performing override on bean: " + bean.toString());

                 }

     }

 }