package com.sri.emo.wizard.completion;
   
   import com.jcorporate.expresso.core.db.DBException;
   import com.sri.emo.dbobj.Node;
   import com.sri.emo.wizard.PageMetadata;
   import com.sri.emo.wizard.ValidValueWithComment;
   import com.sri.emo.wizard.WizardException;
   import com.sri.emo.wizard.expressoimpl.WizardController;
   
  import java.io.Serializable;
  import java.util.*;
  
  /***
   * Wizard page that handles the selection of various relations available.
   *
   * @author Michael Rimov
   * @version 1.0
   */
  public class RelationWizardPage extends CompletionPartsPage {
  
      /***
  	 * 
  	 */
  	private static final long serialVersionUID = 1L;
  
  	/***
       * The prefix of all ids that this class culls from the parameters.  They are
       * of the form of WIZ_DATA_ID + "_" + SomeNumber
       */
      public static final String PARAM_PREFIX = WizardController.WIZ_DATA_ID;
  
      /***
       * The total number of available nodes.
       */
      private int numAvailableRelations = -1;
  
      /***
       * Standard constructor for a wizard page.
       *
       * @param newId        Integer
       * @param pageMetadata PageMetadata
       */
      public RelationWizardPage(Integer newId, PageMetadata pageMetadata) {
          super(newId, pageMetadata);
  
          assert pageMetadata instanceof RelationPageMetadata
                  : "Completion Wizard Relation Page must have metadata of type 'RelationPageMetadata";
      }
  
      /***
       * Intercepts the setData call (which is a Map), grabs the parameters
       * we're interested in, and calls the super.setData() with a Set of all
       * relations that are listed as 'checked'.
       *
       * @param newData the new data for the page. (Should be a map)
       * @throws WizardException upon error.
       */
      public void setData(final Serializable newData) throws WizardException {
  
          assert getNumAvailableRelations() != -1 : "Number of available relations must be initialized";
  
          if (! (newData instanceof Map)) {
              throw new IllegalArgumentException(
                      "Internal Error: Incoming data was: " + newData.getClass().getName() + " and we needed a java.util.Map");
          }
  
          HashSet prunedData = null;
          if (newData == null) {
              prunedData = new HashSet();
          } else {
              final Map givenData = (Map) newData;
              final String searchPrefix = PARAM_PREFIX + "_";
  
              prunedData = new HashSet(givenData.size());
              for (Iterator i = givenData.keySet().iterator(); i.hasNext();) {
                  String oneKey = (String) i.next();
                  if (oneKey.startsWith(searchPrefix)) {
                      prunedData.add(givenData.get(oneKey));
                  }
              }
  
              RelationPageMetadata metadata = getRelationPageMetadata();
  
              if (metadata.getMaxEntries() != null
                      && metadata.getMaxEntries().intValue() < prunedData.size()) {
                  this.addError("Please only choose a maximum of: " + metadata.getMaxEntries().toString() + " choices");
              }
          }
  
          super.setData(prunedData);
      }
  
  
      public Map getSelectedRelations() throws WizardException {
          Set relationKeys = (Set) this.getData();
          if (relationKeys == null) {
              return null;
          }
  
 
         Map returnValue = new HashMap();
         try {
             for (Iterator i = relationKeys.iterator(); i.hasNext();) {
                 String oneKey = (String) i.next();
                 Node n = new Node();
                 n.setNodeId(oneKey);
                 n.retrieve();
                 returnValue.put(oneKey, n);
             }
         } catch (DBException ex) {
             throw new WizardException("Error mapping node ids to actual nodes.", ex);
         }
 
 
         return returnValue;
     }
 
     /***
      * Retrieve the menu.
      *
      * @return ValidValueWithComment[]
      * @throws DBException
      */
     public ValidValueWithComment[] getRelatedNodesMenu() throws DBException {
 
         RelationPageMetadata metadata = (RelationPageMetadata) this.getMetadata();
 
         //Create a list of checkboxes that have comments
         //attached to them.
         Node n = new Node();
         n.setNodeId(metadata.getNodeId());
         n.retrieve();
         Node[] relatedNodes = n.getRelatedNodes(metadata.getPartNodeRelation(), metadata.getNodeType());
         ValidValueWithComment[] selectionMenu = new ValidValueWithComment[relatedNodes.length];
 
         numAvailableRelations = relatedNodes.length;
 
         Set checkedData = (Set) this.getData();
         if (checkedData == null) {
             //Create special case to save us on weird NPEs or special cases
             //in the inner loop.
             checkedData = new HashSet();
         }
 
         for (int relatedIndex = 0; relatedIndex < relatedNodes.length; relatedIndex++) {
             //Build the valid value with comment object.
             selectionMenu[relatedIndex] = new ValidValueWithComment(relatedNodes[relatedIndex].
                     getNodeId(), relatedNodes[relatedIndex].getNodeTitle(),
                     relatedNodes[relatedIndex].getNodeAnnotationRaw());
 
             if (checkedData.contains(selectionMenu[relatedIndex].getKey())) {
                 selectionMenu[relatedIndex].setSelected(true);
             } else {
                 selectionMenu[relatedIndex].setSelected(false);
             }
         }
 
 
         return selectionMenu;
     }
 
 
     /***
      * Type safe page getter.
      *
      * @return RelationPageMetadata
      */
     protected RelationPageMetadata getRelationPageMetadata() {
         return (RelationPageMetadata) this.getMetadata();
     }
 
     public void setNumAvailableRelations(int numAvailableRelations) {
         this.numAvailableRelations = numAvailableRelations;
     }
 
     public int getNumAvailableRelations() {
         return numAvailableRelations;
     }
 }