/***
 * 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.util;

import alterrs.asm.AnnotationVisitor;
import alterrs.asm.Type;

/**
 * An {@link alterrs.asm.AnnotationVisitor} that checks that its methods are
 * properly used.
 * 
 * @author Eric Bruneton
 */
public class CheckAnnotationAdapter implements AnnotationVisitor {

	private final AnnotationVisitor av;

	private final boolean named;

	private boolean end;

	public CheckAnnotationAdapter(final AnnotationVisitor av) {
		this(av, true);
	}

	CheckAnnotationAdapter(final AnnotationVisitor av, final boolean named) {
		this.av = av;
		this.named = named;
	}

	public void visit(final String name, final Object value) {
		checkEnd();
		checkName(name);
		if (!(value instanceof Byte || value instanceof Boolean
				|| value instanceof Character || value instanceof Short
				|| value instanceof Integer || value instanceof Long
				|| value instanceof Float || value instanceof Double
				|| value instanceof String || value instanceof Type
				|| value instanceof byte[] || value instanceof boolean[]
				|| value instanceof char[] || value instanceof short[]
				|| value instanceof int[] || value instanceof long[]
				|| value instanceof float[] || value instanceof double[])) {
			throw new IllegalArgumentException("Invalid annotation value");
		}
		if (av != null) {
			av.visit(name, value);
		}
	}

	public void visitEnum(final String name, final String desc,
			final String value) {
		checkEnd();
		checkName(name);
		CheckMethodAdapter.checkDesc(desc, false);
		if (value == null) {
			throw new IllegalArgumentException("Invalid enum value");
		}
		if (av != null) {
			av.visitEnum(name, desc, value);
		}
	}

	public AnnotationVisitor visitAnnotation(final String name,
			final String desc) {
		checkEnd();
		checkName(name);
		CheckMethodAdapter.checkDesc(desc, false);
		return new CheckAnnotationAdapter(av == null ? null
				: av.visitAnnotation(name, desc));
	}

	public AnnotationVisitor visitArray(final String name) {
		checkEnd();
		checkName(name);
		return new CheckAnnotationAdapter(av == null ? null
				: av.visitArray(name), false);
	}

	public void visitEnd() {
		checkEnd();
		end = true;
		if (av != null) {
			av.visitEnd();
		}
	}

	private void checkEnd() {
		if (end) {
			throw new IllegalStateException(
					"Cannot call a visit method after visitEnd has been called");
		}
	}

	private void checkName(final String name) {
		if (named && name == null) {
			throw new IllegalArgumentException(
					"Annotation value name must not be null");
		}
	}
}
