/**
    * Copyright 2005-2013 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.uif.view;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.krad.uif.container.CollectionGroup;
  import org.kuali.rice.krad.uif.component.Component;
  import org.kuali.rice.krad.uif.field.DataField;
  import org.kuali.rice.krad.uif.field.InputField;
  import org.kuali.rice.krad.uif.util.ComponentUtils;
  import org.kuali.rice.krad.uif.util.ViewCleaner;
  
  import java.beans.PropertyEditor;
  import java.io.Serializable;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * Holds field indexes of a <code>View</code> instance for retrieval
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class ViewIndex implements Serializable {
      private static final long serialVersionUID = 4700818801272201371L;
  
      private Map<String, Component> index;
      private Map<String, DataField> dataFieldIndex;
      private Map<String, CollectionGroup> collectionsIndex;
  
      private Map<String, Component> initialComponentStates;
  
      private Map<String, PropertyEditor> fieldPropertyEditors;
      private Map<String, PropertyEditor> secureFieldPropertyEditors;
      private Map<String, Integer> idSequenceSnapshot;
      private Map<String, Map<String, String>> componentExpressionGraphs;
  
      /**
       * Constructs new instance
       */
      public ViewIndex() {
          index = new HashMap<String, Component>();
          dataFieldIndex = new HashMap<String, DataField>();
          collectionsIndex = new HashMap<String, CollectionGroup>();
          initialComponentStates = new HashMap<String, Component>();
          fieldPropertyEditors = new HashMap<String, PropertyEditor>();
          secureFieldPropertyEditors = new HashMap<String, PropertyEditor>();
          idSequenceSnapshot = new HashMap<String, Integer>();
          componentExpressionGraphs = new HashMap<String, Map<String, String>>();
      }
  
      /**
       * Walks through the View tree and indexes all components found. All components
       * are indexed by their IDs with the special indexing done for certain components
       *
       * <p>
       * <code>DataField</code> instances are indexed by the attribute path.
       * This is useful for retrieving the InputField based on the incoming
       * request parameter
       * </p>
       *
       * <p>
       * <code>CollectionGroup</code> instances are indexed by the collection
       * path. This is useful for retrieving the CollectionGroup based on the
       * incoming request parameter
       * </p>
       */
      protected void index(View view) {
          index = new HashMap<String, Component>();
          dataFieldIndex = new HashMap<String, DataField>();
          collectionsIndex = new HashMap<String, CollectionGroup>();
          fieldPropertyEditors = new HashMap<String, PropertyEditor>();
          secureFieldPropertyEditors = new HashMap<String, PropertyEditor>();
  
          indexComponent(view);
      }
  
      /**
       * Adds an entry to the main index for the given component. If the component
       * is of type <code>DataField</code> or <code>CollectionGroup</code> an
       * entry is created in the corresponding indexes for those types as well. Then
       * the #indexComponent method is called for each of the component's children
       *
       * <p>
       * If the component is already contained in the indexes, it will be replaced
      * </p>
      *
      * <p>
      * Special processing is done for DataField instances to register their property editor which will
      * be used for form binding
      * </p>
      *
      * @param component - component instance to index
      */
     public void indexComponent(Component component) {
         if (component == null) {
             return;
         }
 
         index.put(component.getId(), component);
 
         if (component instanceof DataField) {
             DataField field = (DataField) component;
             dataFieldIndex.put(field.getBindingInfo().getBindingPath(), field);
 
             // pull out information we will need to support the form post
             if (component.isRender()) {
                 if (field.hasSecureValue()) {
                     secureFieldPropertyEditors.put(field.getBindingInfo().getBindingPath(), field.getPropertyEditor());
                 } else {
                     fieldPropertyEditors.put(field.getBindingInfo().getBindingPath(), field.getPropertyEditor());
                 }
             }
         } else if (component instanceof CollectionGroup) {
             CollectionGroup collectionGroup = (CollectionGroup) component;
             collectionsIndex.put(collectionGroup.getBindingInfo().getBindingPath(), collectionGroup);
         }
 
         for (Component nestedComponent : component.getComponentsForLifecycle()) {
             indexComponent(nestedComponent);
         }
     }
 
     /**
      * Invoked after the view lifecycle or component refresh has run to clear indexes that are not
      * needed for the post
      */
     public void clearIndexesAfterRender() {
         // build list of factory ids for components whose initial state needs to be keep
         Set<String> holdIds = new HashSet<String>();
         Set<String> holdFactoryIds = new HashSet<String>();
         for (Component component : index.values()) {
             if (component != null) {
                 // if component has a refresh condition we need to keep it
                 if ((StringUtils.isNotBlank(component.getProgressiveRender()) || StringUtils.isNotBlank(
                         component.getConditionalRefresh()) || component.getRefreshTimer() > 0 ||
                         (component.getRefreshWhenChangedPropertyNames() != null &&
                                 !component.getRefreshWhenChangedPropertyNames().isEmpty()) ||
                         component.isRefreshedByAction() || component.isDisclosedByAction()) &&
                         !component.isDisableSessionPersistence()) {
                     holdFactoryIds.add(component.getBaseId());
                     holdIds.add(component.getId());
                 }
                 // if component is marked as persist in session we need to keep it
                 else if (component.isForceSessionPersistence()) {
                     holdFactoryIds.add(component.getBaseId());
                     holdIds.add(component.getId());
                 }
                 // if component is a collection we need to keep it
                 else if (component instanceof CollectionGroup && !component.isDisableSessionPersistence()) {
                     ViewCleaner.cleanCollectionGroup((CollectionGroup) component);
                     holdFactoryIds.add(component.getBaseId());
                     holdIds.add(component.getId());
                 }
                 // if component is input field and has a query we need to keep the final state
                 else if ((component instanceof InputField) && !component.isDisableSessionPersistence()) {
                     InputField inputField = (InputField) component;
                     if ((inputField.getAttributeQuery() != null) || ((inputField.getSuggest() != null) && inputField
                             .getSuggest().isRender())) {
                         holdIds.add(component.getId());
                     }
                 }
             }
         }
 
         // remove initial states for components we don't need for post
         Map<String, Component> holdInitialComponentStates = new HashMap<String, Component>();
         for (String factoryId : initialComponentStates.keySet()) {
             if (holdFactoryIds.contains(factoryId)) {
                 holdInitialComponentStates.put(factoryId, initialComponentStates.get(factoryId));
             }
         }
         initialComponentStates = holdInitialComponentStates;
 
         // remove final states for components we don't need for post
         Map<String, Component> holdComponentStates = new HashMap<String, Component>();
         for (String id : index.keySet()) {
             if (holdIds.contains(id)) {
                 Component component = index.get(id);
                 holdComponentStates.put(id, component);
 
                 // hold expressions for refresh (since they could have been pushed from a parent)
                 if (!component.getRefreshExpressionGraph().isEmpty()) {
                     componentExpressionGraphs.put(component.getBaseId(), component.getRefreshExpressionGraph());
                 }
             }
         }
         index = holdComponentStates;
 
         dataFieldIndex = new HashMap<String, DataField>();
     }
 
     /**
      * Retrieves a <code>Component</code> from the view index by Id
      *
      * @param id - id for the component to retrieve
      * @return Component instance found in index, or null if no such component exists
      */
     public Component getComponentById(String id) {
         return index.get(id);
     }
 
     /**
      * Retrieves a <code>DataField</code> instance from the index
      *
      * @param propertyPath - full path of the data field (from the form)
      * @return DataField instance for the path or Null if not found
      */
     public DataField getDataFieldByPath(String propertyPath) {
         return dataFieldIndex.get(propertyPath);
     }
 
     /**
      * Retrieves a <code>DataField</code> instance that has the given property name
      * specified (note this is not the full binding path and first match is returned)
      *
      * @param propertyName - property name for field to retrieve
      * @return DataField instance found or null if not found
      */
     public DataField getDataFieldByPropertyName(String propertyName) {
         DataField dataField = null;
 
         for (DataField field : dataFieldIndex.values()) {
             if (StringUtils.equals(propertyName, field.getPropertyName())) {
                 dataField = field;
                 break;
             }
         }
 
         return dataField;
     }
 
     /**
      * Gets the Map that contains attribute field indexing information. The Map
      * key points to an attribute binding path, and the Map value is the
      * <code>DataField</code> instance
      *
      * @return Map<String, DataField> data fields index map
      */
     public Map<String, DataField> getDataFieldIndex() {
         return this.dataFieldIndex;
     }
 
     /**
      * Gets the Map that contains collection indexing information. The Map key
      * gives the binding path to the collection, and the Map value givens the
      * <code>CollectionGroup</code> instance
      *
      * @return Map<String, CollectionGroup> collection index map
      */
     public Map<String, CollectionGroup> getCollectionsIndex() {
         return this.collectionsIndex;
     }
 
     /**
      * Retrieves a <code>CollectionGroup</code> instance from the index
      *
      * @param collectionPath - full path of the collection (from the form)
      * @return CollectionGroup instance for the collection path or Null if not
      *         found
      */
     public CollectionGroup getCollectionGroupByPath(String collectionPath) {
         return collectionsIndex.get(collectionPath);
     }
 
     /**
      * Preserves initial state of components needed for doing component refreshes
      *
      * <p>
      * Some components, such as those that are nested or created in code cannot be requested from the
      * spring factory to get new instances. For these a copy of the component in its initial state is
      * set in this map which will be used when doing component refreshes (which requires running just that
      * component's lifecycle)
      * </p>
      *
      * <p>
      * Map entries are added during the perform initialize phase from {@link org.kuali.rice.krad.uif.service.ViewHelperService}
      * </p>
      *
      * @return Map<String, Component> - map with key giving the factory id for the component and the value the
      *         component
      *         instance
      */
     public Map<String, Component> getInitialComponentStates() {
         return initialComponentStates;
     }
 
     /**
      * Adds a copy of the given component instance to the map of initial component states keyed
      *
      * <p>
      * Component is only added if its factory id is not set yet (which would happen if it had a spring bean id
      * and we can get the state from Spring). Once added the factory id will be set to the component id
      * </p>
      *
      * @param component - component instance to add
      */
     public void addInitialComponentStateIfNeeded(Component component) {
         if (StringUtils.isBlank(component.getBaseId())) {
             component.setBaseId(component.getId());
             initialComponentStates.put(component.getBaseId(), ComponentUtils.copy(component));
         }
     }
 
     /**
      * Setter for the map holding initial component states
      *
      * @param initialComponentStates
      */
     public void setInitialComponentStates(Map<String, Component> initialComponentStates) {
         this.initialComponentStates = initialComponentStates;
     }
 
     /**
      * Maintains configuration of properties that have been configured for the view (if render was set to
      * true) and there corresponding PropertyEdtior (if configured)
      *
      * <p>
      * Information is pulled out of the View during the lifecycle so it can be used when a form post is done
      * from the View. Note if a field is secure, it will be placed in the {@link #getSecureFieldPropertyEditors()} map
      * instead
      * </p>
      *
      * @return Map<String, PropertyEditor> map of property path (full) to PropertyEditor
      */
     public Map<String, PropertyEditor> getFieldPropertyEditors() {
         return fieldPropertyEditors;
     }
 
     /**
      * Maintains configuration of secure properties that have been configured for the view (if render was set to
      * true) and there corresponding PropertyEdtior (if configured)
      *
      * <p>
      * Information is pulled out of the View during the lifecycle so it can be used when a form post is done
      * from the View. Note if a field is non-secure, it will be placed in the {@link #getFieldPropertyEditors()} map
      * instead
      * </p>
      *
      * @return Map<String, PropertyEditor> map of property path (full) to PropertyEditor
      */
     public Map<String, PropertyEditor> getSecureFieldPropertyEditors() {
         return secureFieldPropertyEditors;
     }
 
     /**
      * Map of components ids to starting id sequences used for the component refresh process
      *
      * @return Map<String, Integer> key is component id and value is id sequence value
      */
     public Map<String, Integer> getIdSequenceSnapshot() {
         return idSequenceSnapshot;
     }
 
     /**
      * Adds a sequence value to the id snapshot map for the given component id
      *
      * @param componentId - id for the component the id sequence value is associated it
      * @param sequenceVal - current sequence value to insert into the snapshot
      */
     public void addSequenceValueToSnapshot(String componentId, int sequenceVal) {
         idSequenceSnapshot.put(componentId, sequenceVal);
     }
 
     /**
      * Map of components with their associated expression graphs that will be used during
      * the component refresh process
      *
      * <p>
      * Because expressions that impact a component being refreshed might be on a parent component, a special
      * map needs to be held around that contains expressions that apply to the component and all its nested
      * components. This map is populated during the initial view processing and populating of the property
      * expressions from the initial expression graphs
      * </p>
      *
      * @return Map<String, Map<String, String>> key is component id and value is expression graph map
      * @see org.kuali.rice.krad.uif.util.ExpressionUtils#populatePropertyExpressionsFromGraph(org.kuali.rice.krad.datadictionary.uif.UifDictionaryBean,
      *      boolean)
      */
     public Map<String, Map<String, String>> getComponentExpressionGraphs() {
         return componentExpressionGraphs;
     }
 
 }