/**
* OLAT - Online Learning and Training<br>
* http://www.olat.org
* <p>
* Licensed under the Apache License, Version 2.0 (the "License"); <br>
* you may not use this file except in compliance with the License.<br>
* You may obtain a copy of the License at
* <p>
* http://www.apache.org/licenses/LICENSE-2.0
* <p>
* Unless required by applicable law or agreed to in writing,<br>
* software distributed under the License is distributed on an "AS IS" BASIS, <br>
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. <br>
* See the License for the specific language governing permissions and <br>
* limitations under the License.
* <p>
* Copyright (c) since 2004 at Multimedia- & E-Learning Services (MELS),<br>
* University of Zurich, Switzerland.
* <hr>
* <a href="http://www.openolat.org">
* OpenOLAT - Online Learning and Training</a><br>
* This file has been modified by the OpenOLAT community. Changes are licensed
* under the Apache 2.0 license as the original file.
*/
package org.olat.modules.cp;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.commons.io.IOUtils;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.XPath;
import org.olat.core.gui.components.tree.GenericTreeModel;
import org.olat.core.gui.components.tree.GenericTreeNode;
import org.olat.core.gui.components.tree.TreeNode;
import org.olat.core.logging.AssertException;
import org.olat.core.logging.OLog;
import org.olat.core.logging.Tracing;
import org.olat.core.util.Encoder;
import org.olat.core.util.vfs.VFSLeaf;
import org.olat.core.util.xml.XMLParser;
import org.olat.ims.resources.IMSEntityResolver;
/**
* Description:<br>
* @author Felix Jost
*/
public class CPManifestTreeModel extends GenericTreeModel {
private static final long serialVersionUID = 9216107936843069562L;
private Element rootElement;
private final Map<String,String> nsuris = new HashMap<String,String>(2);
private final Map<String,TreeNode> hrefToTreeNode = new HashMap<String,TreeNode>();
private Map<String,String> resources; // keys: resource att 'identifier'; values: resource att 'href'
private final List<TreeNode> treeNodes = new ArrayList<TreeNode>();
private final String identPrefix;
private final OLog log = Tracing.createLoggerFor(this.getClass());
/**
* Constructor of the content packaging tree model
* @param manifest the imsmanifest.xml file
*/
CPManifestTreeModel(VFSLeaf manifest, String identPrefix) throws IOException {
this.identPrefix = identPrefix;
Document doc = loadDocument(manifest);
initDocument(doc);
}
CPManifestTreeModel(String manifest, String identPrefix) throws IOException {
this.identPrefix = identPrefix;
Document doc = loadDocument(manifest);
initDocument(doc);
}
private void initDocument(Document doc) {
// get all organization elements. need to set namespace
rootElement = doc.getRootElement();
String nsuri = rootElement.getNamespace().getURI();
nsuris.put( "ns", nsuri);
XPath meta = rootElement.createXPath("//ns:organization");
meta.setNamespaceURIs(nsuris);
Element orgaEl = (Element) meta.selectSingleNode(rootElement); // TODO: accept several organizations?
if (orgaEl == null) throw new AssertException("could not find element organization");
XPath metares = rootElement.createXPath("//ns:resources");
metares.setNamespaceURIs(nsuris);
Element elResources = (Element) metares.selectSingleNode(rootElement);
if (elResources == null) throw new AssertException("could not find element resources");
@SuppressWarnings("unchecked")
List<Element> resourcesList = elResources.elements("resource");
resources = new HashMap<String,String>(resourcesList.size());
for (Iterator<Element> iter = resourcesList.iterator(); iter.hasNext();) {
Element elRes = iter.next();
String identVal = elRes.attributeValue("identifier");
String hrefVal = elRes.attributeValue("href");
if (hrefVal != null) { // href is optional element for resource element
try {
hrefVal = URLDecoder.decode(hrefVal, "UTF-8");
} catch (UnsupportedEncodingException e) {
// each JVM must implement UTF-8
}
}
resources.put(identVal, hrefVal);
}
GenericTreeNode gtn = buildNode(orgaEl);
setRootNode(gtn);
rootElement = null; // help gc
resources = null;
}
/**
* @param href
* @return TreeNode representing this href
*/
public TreeNode lookupTreeNodeByHref(String href) {
return hrefToTreeNode.get(href);
}
public List<TreeNode> getFlattedTree() {
return new ArrayList<TreeNode>(treeNodes);
}
public TreeNode getNextNodeWithContent(TreeNode node) {
if(node == null) return null;
int index = treeNodes.indexOf(node);
for(int i=index+1; i<treeNodes.size(); i++) {
TreeNode nextNode = treeNodes.get(i);
if(nextNode.getUserObject() != null) {
return nextNode;
}
}
return null;
}
public TreeNode getPreviousNodeWithContent(TreeNode node) {
if(node == null) return null;
int index = treeNodes.indexOf(node);
for(int i=index; i-->0; ) {
TreeNode nextNode = treeNodes.get(i);
if(nextNode.getUserObject() != null) {
return nextNode;
}
}
return null;
}
private GenericTreeNode buildNode(Element item) {
GenericTreeNode gtn = new GenericTreeNode();
//fxdiff VCRP-13: cp navigation
treeNodes.add(gtn);
// extract title
String title = item.elementText("title");
if (title == null) title = item.attributeValue("identifier");
String identifier = item.attributeValue("identifier");
gtn.setAltText(title);
gtn.setTitle(title);
if (item.getName().equals("organization")) {
// Add first level item for organization
gtn.setIconCssClass("o_cp_org");
gtn.setAccessible(false);
// Special case check: CP with only one page: hide the page and show it directly under the organization element
@SuppressWarnings("unchecked")
List<Element> chds = item.elements("item");
if (chds.size() == 1) {
// check 1: only one child
Element childitem = chds.get(0);
@SuppressWarnings("unchecked")
List<Element> grandChds = childitem.elements("item");
if (grandChds.size() == 0) {
// check 2: no grand children
String identifierref = childitem.attributeValue("identifierref");
String href = resources.get(identifierref);
if (href != null) {
// check 3: a resource is attached to the child
// = success, we have a CP with only one page. Use this page and exit
XPath meta = rootElement.createXPath("//ns:resource[@identifier='" + identifierref + "']");
meta.setNamespaceURIs(nsuris);
gtn.setAccessible(true);
gtn.setUserObject(href);
if (hrefToTreeNode.containsKey(href)){
log.debug("Duplicate href::" + href + " for identifierref::" + identifierref + " and identifier::" + identifier + ", use first one");
} else {
hrefToTreeNode.put(href, gtn);
}
return gtn;
}
}
}
} else if (item.getName().equals("item")) {
gtn.setIconCssClass("o_cp_item");
//set resolved file path directly
String identifierref = item.attributeValue("identifierref");
if(identifierref != null) {
gtn.setIdent("cp" + Encoder.md5hash(identPrefix + identifierref));
}
XPath meta = rootElement.createXPath("//ns:resource[@identifier='" + identifierref + "']");
meta.setNamespaceURIs(nsuris);
String href = resources.get(identifierref);
if (href != null) {
gtn.setUserObject(href);
// allow lookup of a treenode given a href so we can quickly adjust the menu if the user clicks on hyperlinks within the text
if (hrefToTreeNode.containsKey(href)){
log.debug("Duplicate href::" + href + " for identifierref::" + identifierref + " and identifier::" + identifier + ", use first one");
} else {
hrefToTreeNode.put(href, gtn);
}
} else {
gtn.setAccessible(false);
}
}
@SuppressWarnings("unchecked")
List<Element> chds = item.elements("item");
int childcnt = chds.size();
for (int i = 0; i < childcnt; i++) {
Element childitem = chds.get(i);
GenericTreeNode gtnchild = buildNode(childitem);
gtn.addChild(gtnchild);
// set the first accessible child in the hierarchy as delegate when the node itself is not accessible
if (gtn.isAccessible() == false) {
GenericTreeNode nextHierarchyChild = gtnchild;
while (gtn.getDelegate() == null && nextHierarchyChild != null) {
if (nextHierarchyChild.isAccessible()) {
gtn.setDelegate(nextHierarchyChild);
} else {
if (nextHierarchyChild.getChildCount() > 0) {
nextHierarchyChild = (GenericTreeNode) nextHierarchyChild.getChildAt(0);
} else {
nextHierarchyChild = null;
}
}
}
if (!gtn.isAccessible()) {
log.debug("No accessible child found that could be used as delegate for identifier::" + identifier);
}
}
}
return gtn;
}
private Document loadDocument(VFSLeaf documentF) throws IOException {
InputStream in = null;
Document doc = null;
try {
in = documentF.getInputStream();
XMLParser xmlParser = new XMLParser(new IMSEntityResolver());
doc = xmlParser.parse(in, false);
in.close();
} catch (IOException e) {
throw e;
} catch(Exception e) {
throw new IOException("could not read and parse from file " + documentF, e);
}
finally {
IOUtils.closeQuietly(in);
}
return doc;
}
private Document loadDocument(String documentStr) throws IOException {
InputStream in = null;
Document doc = null;
try {
in = new ByteArrayInputStream(documentStr.getBytes());
XMLParser xmlParser = new XMLParser(new IMSEntityResolver());
doc = xmlParser.parse(in, false);
in.close();
} catch (IOException e) {
throw e;
} catch(Exception e) {
throw new IOException("could not read and parse from string " + documentStr, e);
}
finally {
IOUtils.closeQuietly(in);
}
return doc;
}
}