/*
* JBoss, Home of Professional Open Source
* Copyright 2013, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.richfaces.resource.optimizer.faces;
import static org.richfaces.resource.optimizer.strings.Constants.SLASH_JOINER;
import static org.richfaces.resource.optimizer.strings.Constants.SLASH_SPLITTER;
import java.beans.FeatureDescriptor;
import java.text.MessageFormat;
import java.util.Iterator;
import java.util.List;
import javax.el.ELContext;
import javax.el.ELException;
import javax.el.ELResolver;
import javax.el.PropertyNotFoundException;
import javax.faces.application.Resource;
import javax.faces.application.ResourceHandler;
import javax.faces.context.FacesContext;
import com.google.common.collect.Lists;
/**
* @author Nick Belaevski
*
*/
public class ResourceELResolver extends ELResolver {
private void checkBaseAndProperty(Object base, Object property) {
if (base == null && property == null) {
throw new PropertyNotFoundException("base & property are null");
}
}
private String skipEqualPathSegments(Iterator<String> path, Iterator<String> basePath) {
while (path.hasNext()) {
String pathSeg = path.next();
if (basePath.hasNext()) {
String basePathSeg = basePath.next();
if (basePathSeg.equals(pathSeg)) {
continue;
}
}
return pathSeg;
}
return null;
}
private String relativize(String path, String basePath) {
Iterator<String> pathItr = SLASH_SPLITTER.split(path).iterator();
Iterator<String> basePathItr = SLASH_SPLITTER.split(basePath).iterator();
List<String> resultPathSegments = Lists.newArrayList();
String firstNonMatchedSegment = skipEqualPathSegments(pathItr, basePathItr);
while (basePathItr.hasNext()) {
basePathItr.next();
resultPathSegments.add("..");
}
if (firstNonMatchedSegment != null) {
resultPathSegments.add(firstNonMatchedSegment);
}
while (pathItr.hasNext()) {
resultPathSegments.add(pathItr.next());
}
return SLASH_JOINER.join(resultPathSegments);
}
public Object getValue(ELContext context, Object base, Object property) {
checkBaseAndProperty(base, property);
if (base instanceof ResourceHandler) {
ResourceHandler handler = (ResourceHandler) base;
String prop = (String) property;
Resource resource;
if (!prop.contains(":")) {
resource = handler.createResource(prop);
} else {
String[] parts = prop.split(":");
if (parts.length != 2) {
throw new ELException(MessageFormat.format(
"Invalid resource format. Property {0} contains more than one colon (:)", prop));
}
resource = handler.createResource(parts[1], parts[0]);
}
context.setPropertyResolved(true);
if (resource != null) {
String requestPath = resource.getRequestPath();
FacesContext facesContext = (FacesContext) context.getContext(FacesContext.class);
Resource contextResource = CurrentResourceContext.getInstance(facesContext).getResource();
if (contextResource != null) {
requestPath = relativize(requestPath, contextResource.getRequestPath());
}
return requestPath;
}
}
return null;
}
public Class<?> getType(ELContext context, Object base, Object property) {
checkBaseAndProperty(base, property);
return null;
}
public void setValue(ELContext context, Object base, Object property, Object value) {
checkBaseAndProperty(base, property);
}
public boolean isReadOnly(ELContext context, Object base, Object property) {
checkBaseAndProperty(base, property);
return true;
}
@Override
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) {
return null;
}
@Override
public Class<?> getCommonPropertyType(ELContext context, Object base) {
return String.class;
}
}