PortalEvent

package org.jasig.portal;

/**
 * Events which may be arguments to the IChannel receiveEvent() method.
 * @author <a href="mailto:pkharchenko@interactivebusiness.com">Peter Kharchenko</a>
 * @author andrew.petro@yale.edu
 * @version $Revision: 1.7 $
 */
public class PortalEvent {
    
  
    // framework-generated events
    public static final int RENDERING_DONE = 0;
    public static final int SESSION_DONE = 1;
    public static final int UNSUBSCRIBE = 2;

    // layout-generated events
    public static final int EDIT_BUTTON_EVENT = 3;
    public static final int HELP_BUTTON_EVENT = 4;
    public static final int ABOUT_BUTTON_EVENT = 5;
    public static final int DETACH_BUTTON_EVENT = 6;
    public static final int MINIMIZE_EVENT = 7;
    public static final int MAXIMIZE_EVENT = 8;
    
  /**
   * The framework-generated event representing the rendering cycle having
   * finished. The original intent was to broadcast it to the involved channels at the
   * end of each rendering cycle.
   * The framework implementation doesn't actually ever send this event
   * -- listening for it is currently pointless.
   */
  public static final PortalEvent RENDERING_DONE_EVENT = 
      new PortalEvent(RENDERING_DONE, "renderingDone", 
              PortalEventSource.FRAMEWORK_GENERATED);
    
  /**
   * The framework-generated event that is broadcast to
   * channels that were used for a user session which is now ending.
   * Typical usage is to trigger state cleanup in channels that are not
   * user-session-scoped.
   */
  public static final PortalEvent SESSION_DONE_EVENT = 
      new PortalEvent(SESSION_DONE, "sessionDone", 
              PortalEventSource.FRAMEWORK_GENERATED);

  /**
   * The framework-generated event that is sent to
   * a channel when the user unsubscribes from that channel.
   */
  public static final PortalEvent UNSUBSCRIBE_EVENT = 
      new PortalEvent(UNSUBSCRIBE, "unsubscribe", 
              PortalEventSource.FRAMEWORK_GENERATED);

  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its edit control.
   */
  public static final PortalEvent EDIT_BUTTON = 
      new PortalEvent(EDIT_BUTTON_EVENT, "editButtonEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its help control.
   */
  public static final PortalEvent HELP_BUTTON = 
      new PortalEvent(HELP_BUTTON_EVENT, "helpButtonEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its about control.
   */
  public static final PortalEvent ABOUT_BUTTON = 
      new PortalEvent(ABOUT_BUTTON_EVENT, "aboutButtonEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its detach control.
   */
  public static final PortalEvent DETACH_BUTTON = 
      new PortalEvent(DETACH_BUTTON_EVENT, "detachButtonEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its minimize control.
   */
  public static final PortalEvent MINIMIZE = 
      new PortalEvent(MINIMIZE_EVENT, "minimizeEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * The layout-generated event that is sent to
   * a channel when the user actuates its maximize control.
   */
  public static final PortalEvent MAXIMIZE = 
      new PortalEvent(MAXIMIZE_EVENT, "maximizeEvent", 
              PortalEventSource.LAYOUT_GENERATED);
  
  /**
   * Integer representation of an event.  Must be one of the static integers
   * declared in this class.
   */
  private final int eventNumber;

  /**
   * String representation of the event.
   */
  private final String eventName;
  
  /**
   * Source of the event -- curently either FRAMEWORK or LAYOUT.
   */
  private final PortalEventSource source;
  
  /**
   * Constructor which translates from one of the integers representing a
   * PortalEvent to the actual PortalEvent class.
   * @param ev integer representing the event
   * @deprecated instead reference one of the static singleton events.
   */
  public PortalEvent(int ev) {
      
      if (ev < 0 || ev > 8)
          throw new IllegalArgumentException("The integer " + ev + 
                  " does not identify a PortalEvent.");
      
    this.eventNumber = ev;
    
    final String [] eventNameArray =
    {
        "renderingDone",
        "sessionDone",
        "unsubscribe",
        "editButtonEvent",
        "helpButtonEvent",
        "aboutButtonEvent",
        "detachButtonEvent",
        "minimizeEvent",
        "maximizeEvent",
    };
    
    this.eventName = eventNameArray[ev];
    
    if (ev < 3) {
        this.source = PortalEventSource.FRAMEWORK_GENERATED;
    } else {
        this.source = PortalEventSource.LAYOUT_GENERATED;
    }
        
  }

  /**
   * Construct a PortalEvent instance from parameters.
   * @param eventNumber - integer representation of event type
   * @param eventName - String name of event
   * @param source - source type of event
   */
  private PortalEvent(int eventNumber, String eventName, PortalEventSource source) {
      this.eventNumber = eventNumber;
      this.eventName = eventName;
      this.source = source;
  }
  
  /**
   * Get a String representing this event.
   * @return a String representing this event.
   */
  public String getEventName() {
    return this.eventName;
  }

  /**
   * Get an integer representing this event.
   * @return an integer representing this event.
   */
  public int getEventNumber() {
    return this.eventNumber;
  }
  
  /**
   * Get the source type of this event.
   * @return the source type of this event.
   */
  public PortalEventSource getSource() {
      return this.source;
  }
  
  /**
   * Two PortalEvents are equal if they have the same eventNumber.
   * @param other - another object
   * @return true if other is a PortalEvent with the same eventNumber,
   * false otherwise
   */
  public boolean equals(Object other) {
      if (other == null)
          return false;
      if (! (other instanceof PortalEvent))
          return false;
      PortalEvent otherEvent = (PortalEvent) other;
      
      if (otherEvent.eventNumber == this.eventNumber)
          return true;
      
      return false;
  }

  /**
   * The String representation of a PortalEvent is its eventName.
   */
  public String toString() {
      return this.eventName;
  }
  
}