/*

 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package org.apidesign.javap;

import java.io.ByteArrayInputStream;

import java.io.DataInputStream;

import java.io.IOException;

/** An abstract parser for annotation definitions. Analyses the bytes and

 * performs some callbacks to the overriden parser methods.

 *

 * @author Jaroslav Tulach <jtulach@netbeans.org>

 */

public class AnnotationParser {

    protected AnnotationParser() {

    }

    protected void visitAnnotationStart(String type) throws IOException {

    }

    protected void visitAnnotationEnd(String type) throws IOException {

    }

    protected void visitAttr(

        String annoType, String attr, String attrType, String value

    ) throws IOException {

    }

    /** Initialize the parsing with constant pool from <code>cd</code>.

     * 

     * @param attr the attribute defining annotations

     * @param cd constant pool

     * @throws IOException in case I/O fails

     */

    public final void parse(byte[] attr, ClassData cd) throws IOException {

        ByteArrayInputStream is = new ByteArrayInputStream(attr);

        DataInputStream dis = new DataInputStream(is);

        try {

            read(dis, cd);

        } finally {

            is.close();

        }

    }

    private void read(DataInputStream dis, ClassData cd) throws IOException {

    	int cnt = dis.readUnsignedShort();

        for (int i = 0; i < cnt; i++) {

            readAnno(dis, cd);

        }

    }

    private void readAnno(DataInputStream dis, ClassData cd) throws IOException {

        int type = dis.readUnsignedShort();

        String typeName = cd.StringValue(type);

        visitAnnotationStart(typeName);

    	int cnt = dis.readUnsignedShort();

    	for (int i = 0; i < cnt; i++) {

            String attrName = cd.StringValue(dis.readUnsignedShort());

            readValue(dis, cd, typeName, attrName);

        }

        visitAnnotationEnd(typeName);

    }

    private void readValue(DataInputStream dis, ClassData cd, String typeName, String attrName) 

    throws IOException {

        char type = (char)dis.readByte();

        if (type == '@') {

            readAnno(dis, cd);

        } else if ("CFJZsSIDB".indexOf(type) >= 0) { // NOI18N

            int primitive = dis.readUnsignedShort();

            String attrType;

            if (type == 's') {

                attrType = "Ljava_lang_String";

            } else {

                attrType = "" + type;

            }

            visitAttr(typeName, attrName, attrType, cd.StringValue(primitive));

        } else if (type == 'c') {

            int cls = dis.readUnsignedShort();

        } else if (type == '[') {

            int cnt = dis.readUnsignedShort();

            for (int i = 0; i < cnt; i++) {

                readValue(dis, cd, typeName, attrName);

            }

        } else if (type == 'e') {

            int enumT = dis.readUnsignedShort();

            int enumN = dis.readUnsignedShort();

        } else {

            throw new IOException("Unknown type " + type);

        }

    }

}