//
//  ========================================================================
//  Copyright (c) 1995-2017 Mort Bay Consulting Pty. Ltd.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package org.eclipse.jetty.websocket.common;

public final class OpCode
{
    /**
     * OpCode for a Continuation Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte CONTINUATION = (byte)0x00;

    /**
     * OpCode for a Text Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte TEXT = (byte)0x01;

    /**
     * OpCode for a Binary Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte BINARY = (byte)0x02;

    /**
     * OpCode for a Close Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte CLOSE = (byte)0x08;

    /**
     * OpCode for a Ping Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte PING = (byte)0x09;

    /**
     * OpCode for a Pong Frame
     * 
     * @see <a href="https://tools.ietf.org/html/rfc6455#section-11.8">RFC 6455, Section 11.8 (WebSocket Opcode Registry</a>
     */
    public static final byte PONG = (byte)0x0A;

    /**
     * An undefined OpCode
     */
    public static final byte UNDEFINED = (byte)-1;

    public static boolean isControlFrame(byte opcode)
    {
        return (opcode >= CLOSE);
    }

    public static boolean isDataFrame(byte opcode)
    {
        return (opcode == TEXT) || (opcode == BINARY);
    }

    /**
     * Test for known opcodes (per the RFC spec)
     * 
     * @param opcode
     *            the opcode to test
     * @return true if known. false if unknown, undefined, or reserved
     */
    public static boolean isKnown(byte opcode)
    {
        return (opcode == CONTINUATION) || (opcode == TEXT) || (opcode == BINARY) || (opcode == CLOSE) || (opcode == PING) || (opcode == PONG);
    }

    public static String name(byte opcode)
    {
        switch (opcode)
        {
            case -1:
                return "NO-OP";
            case CONTINUATION:
                return "CONTINUATION";
            case TEXT:
                return "TEXT";
            case BINARY:
                return "BINARY";
            case CLOSE:
                return "CLOSE";
            case PING:
                return "PING";
            case PONG:
                return "PONG";
            default:
                return "NON-SPEC[" + opcode + "]";
        }
    }
}
