/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2005 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 clojure.asm.commons;

import clojure.asm.Label;
import clojure.asm.MethodAdapter;
import clojure.asm.MethodVisitor;
import clojure.asm.Opcodes;

/**
 * A {@link MethodAdapter} that can be used to approximate method size.
 *
 * @author Eugene Kuleshov
 */
public class CodeSizeEvaluator extends MethodAdapter implements Opcodes{

private int minSize;

private int maxSize;

public CodeSizeEvaluator(final MethodVisitor mv){
	super(mv);
}

public int getMinSize(){
	return this.minSize;
}

public int getMaxSize(){
	return this.maxSize;
}

public void visitInsn(final int opcode){
	minSize += 1;
	maxSize += 1;
	if(mv != null)
		{
		mv.visitInsn(opcode);
		}
}

public void visitIntInsn(final int opcode, final int operand){
	if(opcode == SIPUSH)
		{
		minSize += 3;
		maxSize += 3;
		}
	else
		{
		minSize += 2;
		maxSize += 2;
		}
	if(mv != null)
		{
		mv.visitIntInsn(opcode, operand);
		}
}

public void visitVarInsn(final int opcode, final int var){
	if(var < 4 && opcode != Opcodes.RET)
		{
		minSize += 1;
		maxSize += 1;
		}
	else if(var >= 256)
		{
		minSize += 4;
		maxSize += 4;
		}
	else
		{
		minSize += 2;
		maxSize += 2;
		}
	if(mv != null)
		{
		mv.visitVarInsn(opcode, var);
		}
}

public void visitTypeInsn(final int opcode, final String desc){
	minSize += 3;
	maxSize += 3;
	if(mv != null)
		{
		mv.visitTypeInsn(opcode, desc);
		}
}

public void visitFieldInsn(
		final int opcode,
		final String owner,
		final String name,
		final String desc){
	minSize += 3;
	maxSize += 3;
	if(mv != null)
		{
		mv.visitFieldInsn(opcode, owner, name, desc);
		}
}

public void visitMethodInsn(
		final int opcode,
		final String owner,
		final String name,
		final String desc){
	if(opcode == INVOKEINTERFACE)
		{
		minSize += 5;
		maxSize += 5;
		}
	else
		{
		minSize += 3;
		maxSize += 3;
		}
	if(mv != null)
		{
		mv.visitMethodInsn(opcode, owner, name, desc);
		}
}

public void visitJumpInsn(final int opcode, final Label label){
	minSize += 3;
	if(opcode == GOTO || opcode == JSR)
		{
		maxSize += 5;
		}
	else
		{
		maxSize += 8;
		}
	if(mv != null)
		{
		mv.visitJumpInsn(opcode, label);
		}
}

public void visitLdcInsn(final Object cst){
	if(cst instanceof Long || cst instanceof Double)
		{
		minSize += 3;
		maxSize += 3;
		}
	else
		{
		minSize += 2;
		maxSize += 3;
		}
	if(mv != null)
		{
		mv.visitLdcInsn(cst);
		}
}

public void visitIincInsn(final int var, final int increment){
	if(var > 255 || increment > 127 || increment < -128)
		{
		minSize += 6;
		maxSize += 6;
		}
	else
		{
		minSize += 3;
		maxSize += 3;
		}
	if(mv != null)
		{
		mv.visitIincInsn(var, increment);
		}
}

public void visitTableSwitchInsn(
		final int min,
		final int max,
		final Label dflt,
		final Label[] labels){
	minSize += 13 + labels.length * 4;
	maxSize += 16 + labels.length * 4;
	if(mv != null)
		{
		mv.visitTableSwitchInsn(min, max, dflt, labels);
		}
}

public void visitLookupSwitchInsn(
		final Label dflt,
		final int[] keys,
		final Label[] labels){
	minSize += 9 + keys.length * 8;
	maxSize += 12 + keys.length * 8;
	if(mv != null)
		{
		mv.visitLookupSwitchInsn(dflt, keys, labels);
		}
}

public void visitMultiANewArrayInsn(final String desc, final int dims){
	minSize += 4;
	maxSize += 4;
	if(mv != null)
		{
		mv.visitMultiANewArrayInsn(desc, dims);
		}
}
}
