/*
    * 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.myfaces.trinidad.facelets;
  
  import java.io.Serializable;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  
  import javax.el.ELException;
  import javax.el.MethodExpression;
  
  import javax.faces.context.FacesContext;
  import javax.faces.el.EvaluationException;
  import javax.faces.el.MethodBinding;
  
  import javax.faces.el.MethodNotFoundException;
  import javax.faces.view.facelets.FaceletContext;
  import javax.faces.view.facelets.MetaRule;
  import javax.faces.view.facelets.Metadata;
  import javax.faces.view.facelets.MetadataTarget;
  import javax.faces.view.facelets.TagAttribute;
  import javax.faces.view.facelets.TagAttributeException;
  
  /**
   * Optional Rule for binding Method[Binding|Expression] properties
   *
   * @author Mike Kienenberger
   * @author Jacob Hookom
   * 
   * Implementation copied from Facelets 1.1.14, as it got hidden by JSF 2.0
   */
  public class MethodRule extends MetaRule {
  
      private final String methodName;
  
      private final Class returnTypeClass;
  
      private final Class[] params;
  
      public MethodRule(String methodName, Class returnTypeClass,
                        Class[] params) {
          this.methodName = methodName;
          this.returnTypeClass = returnTypeClass;
          this.params = params;
      }
  
      public Metadata applyRule(String name, TagAttribute attribute,
                                MetadataTarget meta) {
          if (false == name.equals(this.methodName))
              return null;
  
          if (MethodBinding.class.equals(meta.getPropertyType(name))) {
              Method method = meta.getWriteMethod(name);
              if (method != null) {
                  return new MethodBindingMetadata(method, attribute,
                                                   this.returnTypeClass,
                                                   this.params);
              }
          } else if (MethodExpression.class.equals(meta.getPropertyType(name))) {
              Method method = meta.getWriteMethod(name);
              if (method != null) {
                  return new MethodExpressionMetadata(method, attribute,
                                                      this.returnTypeClass,
                                                      this.params);
              }
          }
  
          return null;
      }
  
      private static class MethodBindingMetadata extends Metadata {
          private final Method _method;
  
          private final TagAttribute _attribute;
  
          private Class[] _paramList;
  
          private Class _returnType;
  
          public MethodBindingMetadata(Method method, TagAttribute attribute,
                                       Class returnType, Class[] paramList) {
              _method = method;
             _attribute = attribute;
             _paramList = paramList;
             _returnType = returnType;
         }
 
         public void applyMetadata(FaceletContext ctx, Object instance) {
             MethodExpression expr =
                 _attribute.getMethodExpression(ctx, _returnType, _paramList);
 
             try {
                 _method.invoke(instance,
                                new Object[] { new LegacyMethodBinding(expr) });
             } catch (InvocationTargetException e) {
                 throw new TagAttributeException(_attribute, e.getCause());
             } catch (Exception e) {
                 throw new TagAttributeException(_attribute, e);
             }
         }
     }
 
     private static class MethodExpressionMetadata extends Metadata {
         private final Method _method;
 
         private final TagAttribute _attribute;
 
         private Class[] _paramList;
 
         private Class _returnType;
 
         public MethodExpressionMetadata(Method method, TagAttribute attribute,
                                         Class returnType, Class[] paramList) {
             _method = method;
             _attribute = attribute;
             _paramList = paramList;
             _returnType = returnType;
         }
 
         public void applyMetadata(FaceletContext ctx, Object instance) {
             MethodExpression expr =
                 _attribute.getMethodExpression(ctx, _returnType, _paramList);
 
             try {
                 _method.invoke(instance, new Object[] { expr });
             } catch (InvocationTargetException e) {
                 throw new TagAttributeException(_attribute, e.getCause());
             } catch (Exception e) {
                 throw new TagAttributeException(_attribute, e);
             }
         }
     }
     
 
     private static class LegacyMethodBinding extends MethodBinding implements Serializable {
 
         private static final long serialVersionUID = 1L;
 
         private final MethodExpression m;
 
         public LegacyMethodBinding(MethodExpression m) {
             this.m = m;
         }
 
         /*
        * (non-Javadoc)
        *
        * @see javax.faces.el.MethodBinding#getType(javax.faces.context.FacesContext)
        */
 
         public Class getType(FacesContext context) throws MethodNotFoundException {
             try {
                 return m.getMethodInfo(context.getELContext()).getReturnType();
             } catch (javax.el.MethodNotFoundException e) {
                 throw new MethodNotFoundException(e.getMessage(),
                                                   e.getCause());
             } catch (ELException e) {
                 throw new EvaluationException(e.getMessage(), e.getCause());
             }
         }
 
         /*
        * (non-Javadoc)
        *
        * @see javax.faces.el.MethodBinding#invoke(javax.faces.context.FacesContext,
        *      java.lang.Object[])
        */
 
         public Object invoke(FacesContext context,
                              Object[] params) throws EvaluationException,
                                                      MethodNotFoundException {
             try {
                 return m.invoke(context.getELContext(), params);
             } catch (javax.el.MethodNotFoundException e) {
                 throw new MethodNotFoundException(e.getMessage(),
                                                   e.getCause());
             } catch (ELException e) {
                 throw new EvaluationException(e.getMessage(), e.getCause());
             }
         }
 
         public String getExpressionString() {
             return m.getExpressionString();
         }
     }
 }