/*
 * 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 org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;

import org.apache.cocoon.forms.binding.JXPathBindingBuilderBase.CommonAttributes;
import org.apache.cocoon.forms.formmodel.Widget;

import org.apache.commons.jxpath.JXPathContext;

/**
 * CustomJXPathBinding
 */
public class CustomJXPathBinding extends JXPathBindingBase
                                 implements Serviceable {

    /**
     * The id of the cforms widget
     */
    private final String widgetId;

    /**
     * The path into the objectModel to select
     */
    private final String xpath;

    /**
     * The actual custom provided binding
     */
    private final AbstractCustomBinding wrappedBinding;

    /**
     * Constructs CustomJXPathBinding
     *
     * @param commonAtts common configuration attributes {@link org.apache.cocoon.forms.binding.JXPathBindingBuilderBase.CommonAttributes}
     * @param widgetId id of the widget to bind to
     * @param xpath jxpath expression to narrow down the context to before calling the wrapped Binding
     * @param wrappedBinding the actual custom written Binding implementation of {@link Binding}
     */
    public CustomJXPathBinding(CommonAttributes commonAtts, String widgetId,
                               String xpath, AbstractCustomBinding wrappedBinding) {
        super(commonAtts);
        this.widgetId = widgetId;
        this.xpath = xpath;
        this.wrappedBinding = wrappedBinding;
        wrappedBinding.setXpath(xpath);
    }

    public String getXPath() { return xpath; }
    public String getId() { return widgetId; }
    public AbstractCustomBinding getWrappedBinding() { return wrappedBinding; }

    /**
     * Delegates the actual loading operation to the provided Custom Binding Class
     * after narrowing down on the selected widget (@id) and context (@path)
     *
     * @param frmModel the narrowed widget-scope from the parent binding
     * @param jxpc the narrowed jxpath context from the parent binding
     * @throws BindingException when the wrapped CustomBinding fails
     */
    public void doLoad(Widget frmModel, JXPathContext jxpc) throws BindingException {
        Widget selectedWidget = selectWidget(frmModel, this.widgetId);
        this.wrappedBinding.loadFormFromModel(selectedWidget, jxpc);
    }

    /**
     * Delegates the actual saving operation to the provided Custom Binding Class
     * after narrowing down on the selected widget (@id) and context (@path)
     *
     * @param frmModel the narrowed widget-scope from the parent binding
     * @param jxpc the narrowed jxpath context from the parent binding
     * @throws BindingException when the wrapped CustomBinding fails
     */
    public void doSave(Widget frmModel, JXPathContext jxpc) throws BindingException {
        Widget selectedWidget = selectWidget(frmModel, this.widgetId);
        this.wrappedBinding.saveFormToModel(selectedWidget, jxpc);
    }

    /**
     * @see org.apache.avalon.framework.service.Serviceable#service(org.apache.avalon.framework.service.ServiceManager)
     */
    public void service(ServiceManager manager) throws ServiceException {
        if (wrappedBinding instanceof Serviceable) {
            ((Serviceable) wrappedBinding).service(manager);
        }
    }
}