package custom;

import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.log4j.Logger;

import com.jalios.jcms.AudienceRights;
import com.jalios.jcms.Category;
import com.jalios.jcms.Channel;
import com.jalios.jcms.Publication;
import com.jalios.jstore.Storable;
import com.jalios.jstore.StoreListener;

/**
 * This StoreListener listens to all Publication "create" and "update" operation.
 * It checks if at least one category is checked for each Audience Right
 * axes, in which case the Publication is declared audienced.
 * 
 * TODO: Trigger a recheck of all Publication on AudienceRight configuration change.
 *    => When AudienceRight is enabled or if an axe is changed after site starts,
 *    some publication are not checked or may have an invalid check.
 *    In this current implementation, you must restart the site if you change
 *    enable AudienceRight or if you change audience right axes.
 */
public class AudiencedPublicationListener implements StoreListener {
  
  private static final Logger logger = Logger.getLogger(AudiencedPublicationListener.class);
  
  /**
   * Key of the attribute we store in the Publication's extraInfo to cache a Boolean
   * to know if the publication has been declared audienced or not.
   */
  public static final String PUBLICATION_AUDIENCED_EXTRAINFO_KEY = "EI.isAudienced";

  Channel channel = Channel.getChannel();
  AudienceRights ar = AudienceRights.getInstance();
  
  public AudiencedPublicationListener() {
    checkAllPublication();
  }
  
  //---------------------------------------------------------------
  // StoreListener methods
  
  public void handleCreate(Storable storable, boolean firstTime) {
    if (ar.isEnabled() && storable instanceof Publication) {
      checkPublication((Publication) storable);
    }
  }
  public void handlePrepareUpdate(Storable storable, Map attributes, boolean firstTime) {
    /* empty */
  }
  public void handleCommitUpdate(Storable storable, Storable oldStorable, boolean firstTime) {
    if (ar.isEnabled() && storable instanceof Publication) {
      checkPublication((Publication) storable);
    }
  }
  public void handleDelete(Storable storable, boolean firstTime) {
    /* empty */
  }
  
  //---------------------------------------------------------------
  // Custom methods

  /**
   * Method to be called after store load (and therefore after audience right
   * has been properly loaded) to iterate on all publication and check their status.
   */
  public void checkAllPublication() {
    if (!ar.isEnabled()) {
      return;
    }
    Set publicationSet = channel.getDataSet(Publication.class);
    for (Iterator it = publicationSet.iterator(); it.hasNext();) {
      Publication pub = (Publication) it.next();
      checkPublication(pub);
    }
  }
  
  /**
   * Check if the given publication is audienced by checking its categories,
   * cache the result in the publiction's extra info.
   */
  public void checkPublication(Publication pub) {
    boolean pubIsAudienced = true;
    // Iterate on all AudienceRight axes
    List axesList = ar.getCategoriesAxesList();
    for (Iterator it = axesList.iterator(); it.hasNext();) {
      Category axeCat = (Category) it.next();
      // Iterate on all publication's categories and check there is
      // at least one category descendant of the axe
      boolean pubHasAxeCat = false;
      Category[] categories = pub.getCategories();
      for (int i = 0; categories != null && i < categories.length; i++) {
        Category pubCat = categories[i];
        if (axeCat.containsDescendant(pubCat)) {
          pubHasAxeCat = true;
          break;
        }
      }
      // Publication has no selected category in this axe, end verification here.
      if (!pubHasAxeCat) {
        pubIsAudienced = false;
        break;
      }
    }
    if (logger.isDebugEnabled() && pubIsAudienced) {
      logger.debug(pub + " is audienced");
    }
    pub.setExtraInfo(PUBLICATION_AUDIENCED_EXTRAINFO_KEY, Boolean.valueOf(pubIsAudienced));
  }
}