/*

  * 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.el.impl.commons;

 import java.util.List;

 import javax.faces.application.Application;

 import javax.servlet.jsp.el.ELException;

 import javax.servlet.jsp.el.FunctionMapper;

 import javax.servlet.jsp.el.VariableResolver;

 import org.apache.commons.el.ArraySuffix;

 import org.apache.commons.el.ComplexValue;

 import org.apache.commons.el.Logger;

 import org.apache.commons.el.PropertySuffix;

 import org.apache.commons.el.ValueSuffix;

 import org.seasar.teeda.core.el.ExpressionProcessor;

 import org.seasar.teeda.core.el.Replacer;

 import org.seasar.teeda.core.util.ApplicationUtil;

 import org.seasar.teeda.core.util.PropertyResolverUtil;

 /**

  * @author shot

  */

 public class ComplexValueReplacer implements Replacer {

     private ExpressionProcessor processor_;

     public ComplexValueReplacer(ExpressionProcessor processor) {

         processor_ = processor;

     }

     public void replace(Object expression) {

         ComplexValue complexValue = (ComplexValue) expression;

         Application application = ApplicationUtil.getApplicationFromContext();

         List suffixes = complexValue.getSuffixes();

         for (int i = 0; i < suffixes.size(); i++) {

             ValueSuffix valueSuffix = (ValueSuffix) suffixes.get(i);

             if (isSuitablePropertySuffix(valueSuffix)) {

                 PropertySuffix propertySuffix = (PropertySuffix) valueSuffix;

                 suffixes.set(i, new JsfPropertySuffix(propertySuffix,

                         application, processor_));

             } else if (isSuitableArraySuffix(valueSuffix)) {

                 ArraySuffix arraySuffix = (ArraySuffix) valueSuffix;

                 suffixes.set(i, new JsfArraySuffix(arraySuffix, application,

                         processor_));

             } else {

                 throw new IllegalStateException();

             }

         }

     }

     private static boolean isSuitablePropertySuffix(ValueSuffix valueSuffix) {

         return (valueSuffix instanceof PropertySuffix)

                 && !(valueSuffix instanceof JsfPropertySuffix);

     }

     private static boolean isSuitableArraySuffix(ValueSuffix valueSuffix) {

         return (valueSuffix instanceof ArraySuffix)

                 && !(valueSuffix instanceof JsfArraySuffix);

     }

     public static class JsfArraySuffix extends ArraySuffix {

         private Application application_;

         private ExpressionProcessor processor_;

         public JsfArraySuffix(ArraySuffix suffix, Application application,

                 ExpressionProcessor processor) {

             super(suffix.getIndex());

             Object o = getIndex();

             processor_ = processor;

             application_ = application;

             processor_.processExpression(o, o.getClass());

         }

         public Object evaluate(Object base, VariableResolver resolver,

                 FunctionMapper mapper, Logger logger) throws ELException {

             if (base == null) {

                 return null;

             }

             Object indexValue = getIndex().evaluate(resolver, mapper, logger);

             if (indexValue == null) {

                 return null;

             }

             Integer index = processor_.toIndex(base, indexValue);

             return PropertyResolverUtil.getValue(application_, base,

                     indexValue, index);

         }

     }

     public static class JsfPropertySuffix extends PropertySuffix {

         private Application application_;

         private ExpressionProcessor processor_;

         public JsfPropertySuffix(PropertySuffix propertySuffix,

                 Application application, ExpressionProcessor processor) {

             super(propertySuffix.getName());

             application_ = application;

             processor_ = processor;

         }

         public Object evaluate(Object base, VariableResolver resolver,

                 FunctionMapper mapper, Logger logger) throws ELException {

             if (base == null) {

                 return null;

             }

             String indexValue = getName();

             if (indexValue == null) {

                 return null;

             }

             Integer index = processor_.toIndex(base, indexValue);

             return PropertyResolverUtil.getValue(application_, base,

                     indexValue, index);

         }

     }

 }