// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Identify.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies DiscJuggler disc images.
//
// --[ License ] --------------------------------------------------------------
//
//     This library is free software; you can redistribute it and/or modify
//     it under the terms of the GNU Lesser General Public License as
//     published by the Free Software Foundation; either version 2.1 of the
//     License, or (at your option) any later version.
//
//     This library 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
//     Lesser General Public License for more details.
//
//     You should have received a copy of the GNU Lesser General Public
//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2019 Natalia Portillo
// ****************************************************************************/

using System;
using System.IO;
using DiscImageChef.CommonTypes.Interfaces;
using DiscImageChef.Console;

namespace DiscImageChef.DiscImages
{
    public partial class DiscJuggler
    {
        public bool Identify(IFilter imageFilter)
        {
            imageStream = imageFilter.GetDataForkStream();

            imageStream.Seek(-4, SeekOrigin.End);
            byte[] dscLenB = new byte[4];
            imageStream.Read(dscLenB, 0, 4);
            int dscLen = BitConverter.ToInt32(dscLenB, 0);

            DicConsole.DebugWriteLine("DiscJuggler plugin", "dscLen = {0}", dscLen);

            if(dscLen >= imageStream.Length) return false;

            byte[] descriptor = new byte[dscLen];
            imageStream.Seek(-dscLen, SeekOrigin.End);
            imageStream.Read(descriptor, 0, dscLen);

            // Sessions
            if(descriptor[0] > 99 || descriptor[0] == 0) return false;

            // Seems all sessions start with this data
            if(descriptor[1]  != 0x00 || descriptor[3]  != 0x00 || descriptor[4]  != 0x00 || descriptor[5]  != 0x00 ||
               descriptor[6]  != 0x00 || descriptor[7]  != 0x00 || descriptor[8]  != 0x00 || descriptor[9]  != 0x00 ||
               descriptor[10] != 0x01 || descriptor[11] != 0x00 || descriptor[12] != 0x00 || descriptor[13] != 0x00 ||
               descriptor[14] != 0xFF || descriptor[15] != 0xFF) return false;

            // Too many tracks
            return descriptor[2] <= 99;
        }
    }
}