/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache 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.apache.org/licenses/LICENSE-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.apache.cocoon.forms.binding;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.apache.avalon.framework.context.Context;
import org.apache.avalon.framework.context.ContextException;
import org.apache.avalon.framework.context.Contextualizable;
import org.apache.cocoon.forms.binding.JXPathBindingManager.Assistant;
import org.apache.cocoon.forms.util.DomHelper;
import org.apache.cocoon.forms.util.JavaScriptHelper;
import org.mozilla.javascript.Function;
import org.w3c.dom.Element;
/**
* Builds a {@link Binding} based on two JavaScript snippets, respectively for loading and saving the form.
* This binding also optionally accepts named child bindings, which are useful when the bound widget is a container.
* <p>
* The syntax for this binding is as follows:
* <pre>
* <fb:javascript id="foo" path="@foo">
* <fb:load-form>
* var appValue = jxpathPointer.getValue();
* var formValue = doLoadConversion(appValue);
* widget.setValue(formValue);
* childBindings["foo"].loadFormFromModel(widget, jxpathContext);
* </fb:load-form>
* <fb:save-form>
* var formValue = widget.getValue();
* var appValue = doSaveConversion(formValue);
* jxpathPointer.setValue(appValue);
* childBindings["foo"].saveFormToModel(widget, jxpathContext);
* </fb:save-form>
* <fb:child-binding name="foo">
* <fb:value id="bar" path="baz"/>
* </fb:child-binding>
* </fb:javascript>
* </pre>
* This example is rather trivial and could be replaced by a simple <fb:value>, but
* it shows the available variables in the script:
* <ul>
* <li><code>widget</code>: the widget identified by the "id" attribute,
* <li><code>jxpathPointer</code>: the JXPath pointer corresponding to the "path" attribute,
* <li><code>jxpathContext</code> (not shown): the JXPath context corresponding to the "path" attribute
* </ul>
* <b>Notes:</b><ul>
* <li>The <fb:save-form> snippet should be ommitted if the "direction" attribute is set to "load".</li>
* <li>The <fb:load-form> snippet should be ommitted if the "direction" attribute is set to "save".</li>
* </ul>
*
* @version $Id$
*/
public class JavaScriptJXPathBindingBuilder extends JXPathBindingBuilderBase
implements Contextualizable {
private Context avalonContext;
public void contextualize(Context context) throws ContextException {
this.avalonContext = context;
}
public JXPathBindingBase buildBinding(Element element, Assistant assistant)
throws BindingException {
try {
CommonAttributes commonAtts = JXPathBindingBuilderBase.getCommonAttributes(element);
String id = DomHelper.getAttribute(element, "id", null);
String path = DomHelper.getAttribute(element, "path", null);
JavaScriptJXPathBinding otherBinding = (JavaScriptJXPathBinding)assistant.getContext().getSuperBinding();
if (otherBinding != null) {
commonAtts = JXPathBindingBuilderBase.mergeCommonAttributes(otherBinding.getCommonAtts(), commonAtts);
if (id == null) {
id = otherBinding.getId();
}
if (path == null) {
path = otherBinding.getPath();
}
}
// Build load script
Function loadScript = null;
if (commonAtts.loadEnabled) {
if (otherBinding != null) {
loadScript = otherBinding.getLoadScript();
}
Element loadElem = DomHelper.getChildElement(element, BindingManager.NAMESPACE, "load-form");
if (loadElem != null) {
loadScript = JavaScriptHelper.buildFunction(loadElem, "loadForm", JavaScriptJXPathBinding.LOAD_PARAMS);
}
}
// Build save script
Function saveScript = null;
if (commonAtts.saveEnabled) {
if (otherBinding != null) {
saveScript = otherBinding.getSaveScript();
}
Element saveElem = DomHelper.getChildElement(element, BindingManager.NAMESPACE, "save-form");
if (saveElem != null) {
saveScript = JavaScriptHelper.buildFunction(saveElem, "saveForm", JavaScriptJXPathBinding.SAVE_PARAMS);
}
}
// Build child bindings
Map childBindings = new HashMap();
if (otherBinding != null) {
Map otherChildren = otherBinding.getChildBindingsMap();
Iterator it = otherChildren.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
childBindings.put(entry.getKey(), entry.getValue());
}
}
Element[] children = DomHelper.getChildElements(element, BindingManager.NAMESPACE, "child-binding");
if (children.length != 0) {
for (int i = 0; i < children.length; i++) {
Element child = children[i];
// Get the binding name and check its uniqueness
String name = DomHelper.getAttribute(child, "name");
JXPathBindingBase[] otherBindings = null;
if (childBindings.containsKey(name)) {
//throw new BindingException("Duplicate name '" + name + "' at " + DomHelper.getLocation(child));
otherBindings = ((ComposedJXPathBindingBase)childBindings.get(name)).getChildBindings();
}
// Build the child binding
JXPathBindingBase[] bindings = assistant.makeChildBindings(child,otherBindings);
if (bindings == null) {
bindings = new JXPathBindingBase[0];
}
ComposedJXPathBindingBase composedBinding = new ComposedJXPathBindingBase(commonAtts, bindings);
composedBinding.enableLogging(getLogger());
childBindings.put(name, composedBinding);
}
}
JXPathBindingBase result = new JavaScriptJXPathBinding(this.avalonContext, commonAtts, id, path, loadScript, saveScript,
Collections.unmodifiableMap(childBindings));
result.enableLogging(getLogger());
return result;
} catch (BindingException e) {
throw e;
} catch (Exception e) {
throw new BindingException("Cannot build binding", e,
DomHelper.getLocationObject(element));
}
}
}