/*
    * Copyright (c) 2005 Regents of the University of California (Regents). Created
    * by TELS, Graduate School of Education, University of California at Berkeley.
    *
    * This software is distributed under the GNU Lesser General Public License, v2.
    *
    * Permission is hereby granted, without written agreement and without license
    * or royalty fees, to use, copy, modify, and distribute this software and its
    * documentation for any purpose, provided that the above copyright notice and
   * the following two paragraphs appear in all copies of this software.
   *
   * REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE. THE SOFTWAREAND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
   * HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
   * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
   *
   * IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
   * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
   * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
   * REGENTS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  package net.sf.sail.core.curnit;
  
  import java.awt.Component;
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.Set;
  
  import net.sf.sail.common.beansupport.ITitleAware;
  import net.sf.sail.core.beans.Pod;
  import net.sf.sail.core.beans.SessionContext;
  import net.sf.sail.core.beans.UnknownPodException;
  import net.sf.sail.core.beans.assembly.PodRegistry;
  import net.sf.sail.core.uuid.CurnitUuid;
  import net.sf.sail.core.uuid.PodUuid;
  
  /**
   * @author turadg
   */
  public class Curnit implements ITitleAware, ICurnit {
  
  	/**
  	 * Registry of pods to use for this curnit
  	 */
  	private static final PodRegistry REGISTRY = PodRegistry
  			.getDefaultRegistry();
  
  	private static final long serialVersionUID = 1L;
  
  	{ // hack for now to ensure that this class is loaded
  		PodArchiveResolver.getSystemResolver();
  	}
  
  	Pod rootPod;
  
  	Set<Pod> referencedPods = new HashSet<Pod>();
  
  	CurnitUuid curnitId;
  
  	String title = "undefined title";
  
  	private boolean assembled = false;
  
  	// set to store the pod id that specifies the root pod, until the root pod
  	// can be found in the registry
  	private PodUuid pendingLookup = null;
  
  	public CurnitUuid getCurnitId() {
  		return curnitId;
  	}
  
  	public void setCurnitId(CurnitUuid curnitId) {
  		this.curnitId = curnitId;
  	}
  
  	public String getTitle() {
  		return title;
  	}
  
  	public void setTitle(String curnitTitle) {
  		this.title = curnitTitle;
  	}
  
  	private void collectReferences(Pod pod) {
  		referencedPods.add(pod);
  		Set<PodUuid> childPodIds = pod.getChildPodIds();
  		for (PodUuid childPodId : childPodIds) {
  			Pod childPod = REGISTRY.getPod(childPodId);
  			collectReferences(childPod);
  		}
  	}
  
  	public void assemble() {
  		if (assembled)
  			throw new IllegalStateException("curnit already assembled");
 
 		refreshRootPod();
 
 		try {
 			rootPod.assemble(REGISTRY);
 		} catch (UnknownPodException e) {
 			e.printStackTrace();
 			throw new RuntimeException(e);
 		}
 		assembled = true;
 	}
 
 	/**
 	 * 
 	 */
 	private void refreshRootPod() {
 		if (rootPod == null) {
 			// pendingLookup gets set in setRootPodId()
 			if (pendingLookup == null) {
 				throw new IllegalStateException(
 						"cannot assemble() before setRootPodId()");
 			} else {
 				rootPod = REGISTRY.getPod(pendingLookup);
 				pendingLookup = null;
 			}
 		}
 	}
 
 	public boolean isAssembled() {
 		return assembled;
 	}
 
 	/**
 	 * @throws UnknownPodException
 	 * 
 	 */
 	private void refreshReferences() throws UnknownPodException {
 		referencedPods.clear();
 		refreshRootPod();
 		collectReferences(rootPod);
 	}
 
 	public Collection<Pod> getReferencedPods() {
 		try {
 			refreshReferences();
 		} catch (UnknownPodException e) {
 			// TODO Auto-generated catch block
 			e.printStackTrace();
 		}
 		return Collections.unmodifiableCollection(referencedPods);
 	}
 
 	public PodUuid getRootPodId() {
 		if (pendingLookup != null) {
 			return pendingLookup;
 		}
 		if (rootPod == null)
 			return null;
 		else
 			return rootPod.getPodId();
 	}
 
 	public void setRootPodId(PodUuid rootPodId) throws UnknownPodException {
 		// the only way the rootPod field gets set
 		this.rootPod = REGISTRY.getPod(rootPodId);
 		// if we can't find the pod for the id right now, delay it to later
 		if (rootPod == null)
 			pendingLookup = rootPodId;
 	}
 
 	/* (non-Javadoc)
 	 * @see net.sf.sail.core.curnit.ICurnit#getRootBean()
 	 */
 	public Object getRootBean() {
 		// get the root pod from the curnit and add it to the SessionContext
 		PodUuid rootPodId = getRootPodId();
 		Pod rootPod = PodRegistry.getDefaultRegistry().getPod(rootPodId);
 
 		return rootPod;
 	}
 
 	/* (non-Javadoc)
 	 * @see net.sf.sail.core.curnit.ICurnit#initialize()
 	 */
 	public void initialize() {
 		if (!isAssembled()) {
 			assemble();
 		}		
 	}
 
 	public void saveCurnit(File file) throws FileNotFoundException,
 			Exception {
 	}
 
 	/* (non-Javadoc)
 	 * @see net.sf.sail.core.curnit.ICurnit#setSessionDataService(net.sf.sail.core.session.SessionDataService)
 	 */
 	public void setSessionContext(SessionContext sessionContext) {
 		// don't need to deal with the session context because the beans inside 
 		// handle it themselves		
 	}
 
 
 
 	/* (non-Javadoc)
 	 * @see net.sf.sail.core.curnit.ICurnit#previewCurnit(java.awt.Component)
 	 */
 	public void previewCurnit(Component component) throws Exception {
 		// TODO Auto-generated method stub
 		
 	}
 
 
 }