/*

 * Copyright (c) 2012, 2013, 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.

 *

 * 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.

 */

import java.io.UnsupportedEncodingException;

import java.util.Arrays;

import java.util.HashMap;

import java.util.Map;

import java.util.logging.ConsoleHandler;

import java.util.logging.Level;

import java.util.logging.Logger;

/**

 * Utility methods for parsing raw JDP packets.

 *

 * @author Alex Schenkman

 */

public class JdpTestUtil {

    static final int HEADER_SIZE = 4 + 2;   // magic + protocol version

    /**

     * Reads two bytes, starting at the given position,

     * and converts them into an int.

     *

     * @param data

     * @param pos

     * @return

     */

    static int decode2ByteInt(byte[] data, int pos) {

        return (((data[pos] & 0xFF) << 8) | (data[pos + 1] & 0xFF));

    }

    /**

     * Reads four bytes, starting at the given position,

     * and converts them into an int.

     *

     * @param data

     * @param pos

     * @return

     */

    static int decode4ByteInt(byte[] data, int pos) {

        int result = data[pos + 3] & 0xFF;

        result = result | ((data[pos + 2] & 0xFF) << 8);

        result = result | ((data[pos + 1] & 0xFF) << 16);

        result = result | ((data[pos] & 0xFF) << 24);

        return result;

    }

    /**

     * Reads an entry from the given byte array, starting at the given position.

     * This is an internal function used by @see readRawPayload(byte[] rawPayload, int size).

     * <p/>

     * The format of an entry is:

     * 2 bytes with the size of the following string.

     * n bytes of characters.

     *

     * @param data

     * @param pos

     * @return

     * @throws UnsupportedEncodingException

     */

    static String decodeEntry(byte[] data, int pos)

            throws UnsupportedEncodingException {

        int size = JdpTestUtil.decode2ByteInt(data, pos);

        pos = pos + 2;

        byte[] raw = Arrays.copyOfRange(data, pos, pos + size);

        return new String(raw, "UTF-8");

    }

    /**

     * Builds a Map with the payload, from the raw data.

     *

     * @param rawData

     * @return

     * @throws UnsupportedEncodingException

     */

    static Map<String, String> readPayload(byte[] rawData)

            throws UnsupportedEncodingException {

        int totalSize = rawData.length;

        int payloadSize = totalSize - HEADER_SIZE;

        byte[] rawPayload = Arrays.copyOfRange(rawData, HEADER_SIZE, HEADER_SIZE + payloadSize);

        Map<String, String> payload = readRawPayload(rawPayload, payloadSize);

        return payload;

    }

    /**

     * Builds a map from the payload's raw data.

     * This is an internal function used by @see readPayload(byte[] rawData)

     *

     * @param rawPayload

     * @param size

     * @return

     * @throws UnsupportedEncodingException

     */

    static Map<String, String> readRawPayload(byte[] rawPayload, int size)

            throws UnsupportedEncodingException {

        String key, value;

        Map<String, String> payload = new HashMap<String, String>();

        for (int pos = 0; pos < size; ) {

            key = decodeEntry(rawPayload, pos);

            pos = pos + 2 + key.length();

            value = decodeEntry(rawPayload, pos);

            pos = pos + 2 + value.length();

            payload.put(key, value);

        }

        return payload;

    }

    static void enableConsoleLogging(Logger log, Level level) throws SecurityException {

        ConsoleHandler handler = new ConsoleHandler();

        handler.setLevel(level);

        log.addHandler(handler);

        log.setLevel(level);

    }

}