/****************************************************************************
    * Copyright (c) 2005, 2006, 2007, 2008, 2009 Imola Informatica.
    * All rights reserved. This program and the accompanying materials
    * are made available under the terms of the LGPL License v2.1
    * which accompanies this distribution, and is available at
    * http://www.gnu.org/licenses/lgpl.html
    ****************************************************************************/
   package it.imolinfo.jbi4corba.webservice.generator.bcm;
   
  import it.imolinfo.jbi4corba.Logger;
  import it.imolinfo.jbi4corba.LoggerFactory;
  
  import org.objectweb.asm.ClassAdapter;
  import org.objectweb.asm.ClassVisitor;
  import org.objectweb.asm.ClassWriter;
  import org.objectweb.asm.FieldVisitor;
  import org.objectweb.asm.MethodVisitor;
  import org.objectweb.asm.Opcodes;
  
  /**
   * This class visit the bytecode of another class and executes the following
   * three main tasks:
   * 1) add java.io.Serializable interface
   * 2) remove getter and setter
   * 3) modify the scope of the member from private to public.
   */
  public class ValueTypeAdapter extends ClassAdapter {
  
    /**
     * Logger.
     */
    private static final Logger LOG
            = LoggerFactory.getLogger(ValueTypeAdapter.class);
  
    /**
     * The Class Writer.
     */
    protected ClassWriter classWriter = null;
  
    /**
     * The class name.
     */
    protected String className = null;
  
    /**
     * Constructor.
     *
     * @param    cv        The class visitor.
     * @param    cw        The class writer.
     * @param    cn        The class name.
     */
    public ValueTypeAdapter(ClassVisitor cv, ClassWriter cw, String cn) {
      super(cv);
      classWriter = cw;
      className = cn;
    }
  
    /**
     * Override.
     * @param version     The version
     * @param access      The access
     * @param name        The name
     * @param signature   The signature
     * @param superName   The super name
     * @param interfaces  The interfaces
     */
      @Override
      public void visit(int version,
                      int access,
                      String name,
                      String signature,
                      String superName,
                      String [] interfaces) {
  
          LOG.debug(">>>>> visit - begin");
  
          LOG.debug("VISIT"
                  + ".\n version="    + version
                  + ";\n access="     + access
                  + ";\n name="       + name
                  + ";\n signature="  + signature
                  + ";\n superName="  + superName
                  + ";\n interfaces=" + interfaces);
  
          // extends java.io.Serializable
          //         java/io/Serializable
  
          if (interfaces == null || interfaces.length == 0) {
  
              // no interfaces found ... create the array and add my own one.
              interfaces = new String [] {"java/io/Serializable"};
  
          } else {
  
              // there are one or more interfaces ...
              // ... adjust the size of the array and add my interface.
              String [] temp = new String [interfaces.length + 1];
  
              System.arraycopy(interfaces, 0, temp, 0, interfaces.length);
             temp[interfaces.length] = "java/io/Serializable";
 
             interfaces = temp;
         }
 
         LOG.debug("<<<<< visit - end");
         super.visit(version, access, name, signature, superName, interfaces);
     }
 
     /**
      * Override.
      * @param access      The access
      * @param name        The name
      * @param desc        The description
      * @param signature   The signature
      * @param value       The value
      * @return            The return
      */
     @Override
     public FieldVisitor visitField(int access,
                                    String name,
                                    String desc,
                                    String signature,
                                    Object value) {
         LOG.debug(">>>>> visitField - begin");
 
         if ((Opcodes.ACC_STATIC & access) != Opcodes.ACC_STATIC) {
             access = Opcodes.ACC_PUBLIC;
         }
         LOG.debug("The field " + name + " will be 'public'.");
 
         LOG.debug(">>>>> visitField - end");
         return super.visitField(access, name, desc, signature, value);
     }
 
     /**
      * Override.
      * @param access      The access
      * @param name        The name
      * @param desc        The description
      * @param signature   The signature
      * @param exceptions  The exceptions
      * @return            The return
      */
     @Override
     public MethodVisitor visitMethod(int access,
             String name,
             String desc,
             String signature,
             String[] exceptions) {
 
         LOG.debug(">>>>> visitMethod - begin");
 
         LOG.debug("visitMethod. access="     + access
                         + "; name="       + name
                         + "; desc="       + desc
                         + "; signature="  + signature
                         + "; exceptions=" + exceptions);
 
         // Excludes getFaultInfo...
         if (!name.equals("getFaultInfo")) {
             // if we found the default constructor then ...
             if (isGetter(name, desc) || isSetter(name, desc)) {
 
                 LOG.debug("<<<<< visitMethod - remove method:" + name);
                 return null;
             }
         }
 
         // else
         LOG.debug("<<<<< visitMethod - untouched:" + name);
         return super.visitMethod(access, name, desc, signature, exceptions);
     }
 
   
     /**
      * @param methodName  The method name
      * @param params      The params
      * @return            The return
      */
     private boolean isGetter(String methodName, String params) {
         if (methodName == null) {
         	return false;
         }
         // else
         if (methodName.startsWith("get") && params.startsWith("()")
                 && methodName.length() > 3) {
             return true;
         }
         // else
         if (methodName.startsWith("is") && params.startsWith("()")
                 && methodName.length() > 2) {
             return true;
         }
         // else
         return false;
     }
 
     /**
      * @param methodName  The method name
      * @param params      The params
      * @return            The return
      */
     private boolean isSetter(String methodName, String params) {
         if (methodName == null) { 
         	return false;
         }
         // else
         if (methodName.length() <= 3) { 
         	return false;
         }
         // else
         if (methodName.startsWith("set") && (! params.startsWith("()"))) {
             return true;
         }
         // else
         return false;
     }
 
 }