/*

  * Copyright 2004-2011 the Seasar Foundation and the Others.

  *

  * Licensed 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.seasar.teeda.core.util;

 import javax.faces.application.Application;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 import javax.faces.el.ValueBinding;

 import org.seasar.framework.container.ExternalContext;

 import org.seasar.framework.container.S2Container;

 /**

  * @author higa

  * @author shot

  */

 public class BindingUtil {

     private BindingUtil() {

     }

     public static String getExpression(String componentName) {

         return "#{" + componentName + "}";

     }

     public static String getExpression(String componentName, String propertyName) {

         return "#{" + componentName + "." + propertyName + "}";

     }

     public static boolean isValueReference(String value) {

         if (value == null) {

             return false;

         }

         int start = value.indexOf("#{");

         if (start < 0) {

             return false;

         }

         int end = value.lastIndexOf('}');

         return (end >= 0 && start < end);

     }

     public static Object getValue(S2Container container, String name) {

         Object var = getValue(container.getExternalContext(), name);

         if (var != null) {

             return var;

         }

         if (container.hasComponentDef(name)) {

             return container.getComponent(name);

         }

         return null;

     }

     public static Object getValue(ExternalContext externalContext, String name) {

         Object var = externalContext.getRequestMap().get(name);

         if (var != null) {

             return var;

         }

         var = externalContext.getRequestParameterMap().get(name);

         if (var != null && !"null".equals(var)) {

             return var;

         }

         var = externalContext.getSessionMap().get(name);

         if (var != null) {

             return var;

         }

         return null;

     }

     public static Object resolveBinding(String value) {

         FacesContext context = FacesContext.getCurrentInstance();

         Application app = context.getApplication();

         ValueBinding vb = app.createValueBinding(value);

         return vb.getValue(context);

     }

     public static String resolveBindingNoException(String value) {

         Object ret = null;

         try {

             ret = resolveBinding(value);

         } catch (Exception ignore) {

             return null;

         }

         return (ret != null) ? ret.toString() : null;

     }

     public static Object getBindingValue(UIComponent component,

             String propertyName) {

         ValueBinding binding = component.getValueBinding(propertyName);

         if (binding != null) {

             FacesContext ctx = FacesContext.getCurrentInstance();

             return binding.getValue(ctx);

         }

         return null;

     }

     public static void setValueBinding(UIComponent component, String name,

             String value) {

         FacesContext ctx = FacesContext.getCurrentInstance();

         Application app = ctx.getApplication();

         ValueBinding binding = app.createValueBinding(value);

         component.setValueBinding(name, binding);

     }

 }