/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2007 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 alterrs.asm.commons;

import alterrs.asm.ClassAdapter;
import alterrs.asm.ClassVisitor;
import alterrs.asm.MethodVisitor;
import alterrs.asm.Opcodes;

/**
 * A {@link ClassAdapter} that merges clinit methods into a single one.
 * 
 * @author Eric Bruneton
 */
public class StaticInitMerger extends ClassAdapter {

	private String name;

	private MethodVisitor clinit;

	private final String prefix;

	private int counter;

	public StaticInitMerger(final String prefix, final ClassVisitor cv) {
		super(cv);
		this.prefix = prefix;
	}

	public void visit(final int version, final int access, final String name,
			final String signature, final String superName,
			final String[] interfaces) {
		cv.visit(version, access, name, signature, superName, interfaces);
		this.name = name;
	}

	public MethodVisitor visitMethod(final int access, final String name,
			final String desc, final String signature, final String[] exceptions) {
		MethodVisitor mv;
		if ("<clinit>".equals(name)) {
			int a = Opcodes.ACC_PRIVATE + Opcodes.ACC_STATIC;
			String n = prefix + counter++;
			mv = cv.visitMethod(a, n, desc, signature, exceptions);

			if (clinit == null) {
				clinit = cv.visitMethod(a, name, desc, null, null);
			}
			clinit.visitMethodInsn(Opcodes.INVOKESTATIC, this.name, n, desc);
		} else {
			mv = cv.visitMethod(access, name, desc, signature, exceptions);
		}
		return mv;
	}

	public void visitEnd() {
		if (clinit != null) {
			clinit.visitInsn(Opcodes.RETURN);
			clinit.visitMaxs(0, 0);
		}
		cv.visitEnd();
	}
}
