ResetItemAttachmentListener.java

/**********************************************************************************
 * $URL: https://source.sakaiproject.org/svn/sam/trunk/samigo-app/src/java/org/sakaiproject/tool/assessment/ui/listener/author/ResetItemAttachmentListener.java $
 * $Id: ResetItemAttachmentListener.java 106463 2012-04-02 12:20:09Z david.horwitz@uct.ac.za $
 ***********************************************************************************
 *
 * Copyright (c) 2004, 2005, 2006, 2008 The Sakai 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/ECL-2.0
 *
 * 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.sakaiproject.tool.assessment.ui.listener.author;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import javax.faces.event.AbortProcessingException;
import javax.faces.event.ActionEvent;
import javax.faces.event.ActionListener;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.sakaiproject.content.api.ContentResource;
import org.sakaiproject.exception.IdUnusedException;
import org.sakaiproject.exception.PermissionException;
import org.sakaiproject.exception.TypeException;
import org.sakaiproject.tool.assessment.data.ifc.assessment.AttachmentIfc;
import org.sakaiproject.tool.assessment.data.ifc.assessment.ItemDataIfc;
import org.sakaiproject.tool.assessment.services.ItemService;
import org.sakaiproject.tool.assessment.services.PublishedItemService;
import org.sakaiproject.tool.assessment.services.assessment.AssessmentService;
import org.sakaiproject.tool.assessment.services.assessment.PublishedAssessmentService;
import org.sakaiproject.tool.assessment.ui.bean.author.AuthorBean;
import org.sakaiproject.tool.assessment.ui.bean.author.ItemAuthorBean;
import org.sakaiproject.tool.assessment.ui.listener.util.ContextUtil;

/**
 * <p>Title: Samigo</p>
 * <p>Description: Sakai Assessment Manager</p>
 * @version $Id: ResetItemAttachmentListener.java 106463 2012-04-02 12:20:09Z david.horwitz@uct.ac.za $
 */

public class ResetItemAttachmentListener
    implements ActionListener
{
  private static Log log = LogFactory.getLog(ResetItemAttachmentListener.class);

  public ResetItemAttachmentListener()
  {
  }

  public void processAction(ActionEvent ae) throws AbortProcessingException {
	AuthorBean author = (AuthorBean) ContextUtil.lookupBean("author");
	boolean isEditPendingAssessmentFlow =  author.getIsEditPendingAssessmentFlow();
	ItemService itemService = null;
	AssessmentService assessmentService = null;
	if (isEditPendingAssessmentFlow) {
		itemService = new ItemService();
		assessmentService = new AssessmentService();
	}
	else {
		itemService = new PublishedItemService();
		assessmentService = new PublishedAssessmentService();
	}

    ItemAuthorBean itemauthorBean = (ItemAuthorBean) ContextUtil.lookupBean("itemauthor");
    String itemId = itemauthorBean.getItemId();
    if (itemId !=null && !("").equals(itemId)){
      ItemDataIfc item = itemService.getItem(itemId);
      log.debug("*** item attachment="+item.getItemAttachmentList());
      resetItemAttachment(itemauthorBean.getResourceHash(), item.getItemAttachmentList(), assessmentService);
    }
    else{
      resetItemAttachment(itemauthorBean.getResourceHash(), new ArrayList(), assessmentService);
    }
  }

    private void resetItemAttachment(HashMap resourceHash, List attachmentList, AssessmentService service){
    // 1. we need to make sure that attachment removed/added by file picker 
    //    will be restored/remove when user cancels the entire modification
    if (attachmentList != null){
      for (int i=0; i<attachmentList.size(); i++){
         AttachmentIfc attach = (AttachmentIfc) attachmentList.get(i);
         try{
           ContentResource cr = AssessmentService.getContentHostingService().getResource(attach.getResourceId());
	 }
         catch (PermissionException e) {
           log.warn("PermissionException from ContentHostingService:"+e.getMessage());
         }
         catch (IdUnusedException e) {
           log.warn("IdUnusedException from ContentHostingService:"+e.getMessage());
           // <-- bad sign, 
           // use case: ContentHosting deleted the resource
           // and user cancel out all the modification
           // including those that CHS has removed
           // according to Glenn , it is a bug in CHS.
           // so we would just do clean up to avoid having attachments
           // points to empty resources
           log.warn("***2.removing an empty item attachment association, attachmentId="+attach.getAttachmentId());
           service.removeItemAttachment(attach.getAttachmentId().toString());

           /* forget it #1
           if (resourceHash!=null){
             ContentResource old_cr = (ContentResource) resourceHash.get(attach.getResourceId());
             if (old_cr!=null){ 
               resourceHash.remove(attach.getResourceId());
	     }
	   }
           */
         }
         catch (TypeException e) {
    	   log.warn("TypeException from ContentHostingService:"+e.getMessage());
	 }
      }
    }

    /* forget it #2
       the fact that resources belongs to other item get deleted is too great if there is a
        mistake in the code or sequence of users action that I haven't foreseen. So I am commenting 
        this out. These resources shall remain in the DB as orphan. Let's leave the clean up for CHS.
        Afterall, it shan't commit before the tool tell it to.
    // 2. any leftover in resourceHash are files that are uploaded
    //    but has no association with the item and we should remove
    //    it. use case: add attachment and cancel the entire modification
    removeLeftOverResources(resourceHash);
    // VERY IMPORTANT to clean up itemauthorBean.resourceHash
    itemauthorBean.setResourceHash(null); 
    */
  }

  /* forget it #3
  private void removeLeftOverResources(HashMap resourceHash){
    if (resourceHash == null) return;
    Set keys = resourceHash.keySet();
    Iterator iter1 = keys.iterator();
    while (iter1.hasNext()){
      String resourceId = (String)iter1.next();
      try{
       log.debug("***removing left over resourceId="+resourceId);
        ContentHostingService.removeResource(resourceId);
      }
      catch (PermissionException e) {
        log.warn("PermissionException from ContentHostingService:"+e.getMessage());
      }
      catch (IdUnusedException e) {
        log.warn("IdUnusedException from ContentHostingService:"+e.getMessage());
      }
      catch (TypeException e) {
        log.warn("TypeException from ContentHostingService:"+e.getMessage());
      }
      catch (InUseException e) {
        log.warn("InUseException from ContentHostingService:"+e.getMessage());
      }
    }
  }
  */

 }