/***
    * ASM: a very small and fast Java bytecode manipulation framework
    * Copyright (c) 2000-2011 INRIA, France Telecom
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the copyright holders nor the names of its
   *    contributors may be used to endorse or promote products derived from
   *    this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   * THE POSSIBILITY OF SUCH DAMAGE.
   */
  package org.apache.tapestry5.internal.plastic.asm.optimizer;
  
  import java.util.HashMap;
  
  import org.apache.tapestry5.internal.plastic.asm.AnnotationVisitor;
  import org.apache.tapestry5.internal.plastic.asm.Attribute;
  import org.apache.tapestry5.internal.plastic.asm.FieldVisitor;
  import org.apache.tapestry5.internal.plastic.asm.Label;
  import org.apache.tapestry5.internal.plastic.asm.MethodVisitor;
  import org.apache.tapestry5.internal.plastic.asm.Opcodes;
  import org.apache.tapestry5.internal.plastic.asm.Type;
  import org.apache.tapestry5.internal.plastic.asm.TypePath;
  import org.apache.tapestry5.internal.plastic.asm.commons.Remapper;
  import org.apache.tapestry5.internal.plastic.asm.commons.RemappingMethodAdapter;
  
  /**
   * A {@link MethodVisitor} that renames fields and methods, and removes debug
   * info.
   * 
   * @author Eugene Kuleshov
   */
  public class MethodOptimizer extends RemappingMethodAdapter implements Opcodes {
  
      private final ClassOptimizer classOptimizer;
  
      public MethodOptimizer(ClassOptimizer classOptimizer, int access,
              String desc, MethodVisitor mv, Remapper remapper) {
          super(Opcodes.ASM5, access, desc, mv, remapper);
          this.classOptimizer = classOptimizer;
      }
  
      // ------------------------------------------------------------------------
      // Overridden methods
      // ------------------------------------------------------------------------
  
      @Override
      public void visitParameter(String name, int access) {
          // remove parameter info
      }
  
      @Override
      public AnnotationVisitor visitAnnotationDefault() {
          // remove annotations
          return null;
      }
  
      @Override
      public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
          // remove annotations
          return null;
      }
  
      @Override
      public AnnotationVisitor visitTypeAnnotation(int typeRef,
              TypePath typePath, String desc, boolean visible) {
          return null;
      }
  
      @Override
      public AnnotationVisitor visitParameterAnnotation(final int parameter,
              final String desc, final boolean visible) {
          // remove annotations
          return null;
      }
  
      @Override
      public void visitLocalVariable(final String name, final String desc,
              final String signature, final Label start, final Label end,
              final int index) {
          // remove debug info
     }
 
     @Override
     public void visitLineNumber(final int line, final Label start) {
         // remove debug info
     }
 
     @Override
     public void visitFrame(int type, int local, Object[] local2, int stack,
             Object[] stack2) {
         // remove frame info
     }
 
     @Override
     public void visitAttribute(Attribute attr) {
         // remove non standard attributes
     }
 
     @Override
     public void visitLdcInsn(Object cst) {
         if (!(cst instanceof Type)) {
             super.visitLdcInsn(cst);
             return;
         }
 
         // transform Foo.class for 1.2 compatibility
         String ldcName = ((Type) cst).getInternalName();
         String fieldName = "class$" + ldcName.replace('/', '$');
         if (!classOptimizer.syntheticClassFields.contains(ldcName)) {
             classOptimizer.syntheticClassFields.add(ldcName);
             FieldVisitor fv = classOptimizer.syntheticFieldVisitor(ACC_STATIC
                     | ACC_SYNTHETIC, fieldName, "Ljava/lang/Class;");
             fv.visitEnd();
         }
 
         String clsName = classOptimizer.clsName;
         mv.visitFieldInsn(GETSTATIC, clsName, fieldName, "Ljava/lang/Class;");
     }
     
     @Override
     public void visitMethodInsn(int opcode, String owner, String name, String desc, boolean itf) {
         // rewrite boxing method call to use constructor to keep 1.3/1.4 compatibility
         String[] constructorParams;
         if (opcode == INVOKESTATIC && name.equals("valueOf") &&
             (constructorParams = BOXING_MAP.get(owner + desc)) != null) {
             String type = constructorParams[0];
             String initDesc = constructorParams[1];
             super.visitTypeInsn(NEW, type);
             super.visitInsn(DUP);
             super.visitInsn((initDesc == "(J)V" || initDesc == "(D)V")? DUP2_X2: DUP2_X1);
             super.visitInsn(POP2);
             super.visitMethodInsn(INVOKESPECIAL, type, "<init>", initDesc, false);
             return;
         }
         super.visitMethodInsn(opcode, owner, name, desc, itf);
     }
     
     private static final HashMap<String, String[]> BOXING_MAP;
     static {
         String[][] boxingNames = {
             // Boolean.valueOf is 1.4 and is used by the xml package, so no rewrite
             { "java/lang/Byte",      "(B)V" },
             { "java/lang/Short",     "(S)V" },
             { "java/lang/Character", "(C)V" },
             { "java/lang/Integer",   "(I)V" },
             { "java/lang/Long",      "(J)V" },
             { "java/lang/Float",     "(F)V" },
             { "java/lang/Double",    "(D)V" },
         };
         HashMap<String, String[]> map = new HashMap<String, String[]>();
         for(String[] boxingName: boxingNames) {
             String wrapper = boxingName[0];
             String desc = boxingName[1];
             String boxingMethod = wrapper + '(' + desc.charAt(1) + ")L" + wrapper + ';';
             map.put(boxingMethod, boxingName);
         }
         BOXING_MAP = map;
     }
 }