// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Session.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
//     Decodes CD session structures.
//
// --[ 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 © 2011-2020 Natalia Portillo
// ****************************************************************************/

using System.Diagnostics.CodeAnalysis;
using System.Text;
using Aaru.Console;
using Aaru.Helpers;

namespace Aaru.Decoders.CD
{
    // Information from the following standards:
    // ANSI X3.304-1997
    // T10/1048-D revision 9.0
    // T10/1048-D revision 10a
    // T10/1228-D revision 7.0c
    // T10/1228-D revision 11a
    // T10/1363-D revision 10g
    // T10/1545-D revision 1d
    // T10/1545-D revision 5
    // T10/1545-D revision 5a
    // T10/1675-D revision 2c
    // T10/1675-D revision 4 T10/1836-D revision 2g
    [SuppressMessage("ReSharper", "InconsistentNaming"), SuppressMessage("ReSharper", "MemberCanBeInternal"),
     SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
    public static class Session
    {
        public static CDSessionInfo? Decode(byte[] CDSessionInfoResponse)
        {
            if(CDSessionInfoResponse        == null ||
               CDSessionInfoResponse.Length <= 4)
                return null;

            var decoded = new CDSessionInfo
            {
                DataLength           = BigEndianBitConverter.ToUInt16(CDSessionInfoResponse, 0),
                FirstCompleteSession = CDSessionInfoResponse[2],
                LastCompleteSession  = CDSessionInfoResponse[3]
            };

            decoded.TrackDescriptors = new TrackDataDescriptor[(decoded.DataLength - 2) / 8];

            if(decoded.DataLength + 2 != CDSessionInfoResponse.Length)
            {
                AaruConsole.DebugWriteLine("CD Session Info decoder",
                                           "Expected CDSessionInfo size ({0} bytes) is not received size ({1} bytes), not decoding",
                                           decoded.DataLength + 2, CDSessionInfoResponse.Length);

                return null;
            }

            for(int i = 0; i < (decoded.DataLength - 2) / 8; i++)
            {
                decoded.TrackDescriptors[i].Reserved1   = CDSessionInfoResponse[0 + (i * 8) + 4];
                decoded.TrackDescriptors[i].ADR         = (byte)((CDSessionInfoResponse[1 + (i * 8) + 4] & 0xF0) >> 4);
                decoded.TrackDescriptors[i].CONTROL     = (byte)(CDSessionInfoResponse[1 + (i * 8) + 4] & 0x0F);
                decoded.TrackDescriptors[i].TrackNumber = CDSessionInfoResponse[2 + (i * 8) + 4];
                decoded.TrackDescriptors[i].Reserved2   = CDSessionInfoResponse[3 + (i * 8) + 4];

                decoded.TrackDescriptors[i].TrackStartAddress =
                    BigEndianBitConverter.ToUInt32(CDSessionInfoResponse, 4 + (i * 8) + 4);
            }

            return decoded;
        }

        public static string Prettify(CDSessionInfo? CDSessionInfoResponse)
        {
            if(CDSessionInfoResponse == null)
                return null;

            CDSessionInfo response = CDSessionInfoResponse.Value;

            var sb = new StringBuilder();

            sb.AppendFormat("First complete session number: {0}", response.FirstCompleteSession).AppendLine();
            sb.AppendFormat("Last complete session number: {0}", response.LastCompleteSession).AppendLine();

            foreach(TrackDataDescriptor descriptor in response.TrackDescriptors)
            {
                sb.AppendFormat("First track number in last complete session: {0}", descriptor.TrackNumber).
                   AppendLine();

                sb.AppendFormat("Track starts at LBA {0}, or MSF {1:X2}:{2:X2}:{3:X2}", descriptor.TrackStartAddress,
                                (descriptor.TrackStartAddress & 0x0000FF00) >> 8,
                                (descriptor.TrackStartAddress & 0x00FF0000) >> 16,
                                (descriptor.TrackStartAddress & 0xFF000000) >> 24).AppendLine();

                switch((TocAdr)descriptor.ADR)
                {
                    case TocAdr.NoInformation:
                        sb.AppendLine("Q subchannel mode not given");

                        break;
                    case TocAdr.CurrentPosition:
                        sb.AppendLine("Q subchannel stores current position");

                        break;
                    case TocAdr.ISRC:
                        sb.AppendLine("Q subchannel stores ISRC");

                        break;
                    case TocAdr.MediaCatalogNumber:
                        sb.AppendLine("Q subchannel stores media catalog number");

                        break;
                }

                if((descriptor.CONTROL & (byte)TocControl.ReservedMask) == (byte)TocControl.ReservedMask)
                    sb.AppendFormat("Reserved flags 0x{0:X2} set", descriptor.CONTROL).AppendLine();
                else
                {
                    switch((TocControl)(descriptor.CONTROL & 0x0D))
                    {
                        case TocControl.TwoChanNoPreEmph:
                            sb.AppendLine("Stereo audio track with no pre-emphasis");

                            break;
                        case TocControl.TwoChanPreEmph:
                            sb.AppendLine("Stereo audio track with 50/15 μs pre-emphasis");

                            break;
                        case TocControl.FourChanNoPreEmph:
                            sb.AppendLine("Quadraphonic audio track with no pre-emphasis");

                            break;
                        case TocControl.FourChanPreEmph:
                            sb.AppendLine("Stereo audio track with 50/15 μs pre-emphasis");

                            break;
                        case TocControl.DataTrack:
                            sb.AppendLine("Data track, recorded uninterrupted");

                            break;
                        case TocControl.DataTrackIncremental:
                            sb.AppendLine("Data track, recorded incrementally");

                            break;
                    }

                    sb.AppendLine((descriptor.CONTROL & (byte)TocControl.CopyPermissionMask) ==
                                  (byte)TocControl.CopyPermissionMask ? "Digital copy of track is permitted"
                                      : "Digital copy of track is prohibited");

                #if DEBUG
                    if(descriptor.Reserved1 != 0)
                        sb.AppendFormat("Reserved1 = 0x{0:X2}", descriptor.Reserved1).AppendLine();

                    if(descriptor.Reserved2 != 0)
                        sb.AppendFormat("Reserved2 = 0x{0:X2}", descriptor.Reserved2).AppendLine();
                #endif

                    sb.AppendLine();
                }
            }

            return sb.ToString();
        }

        public static string Prettify(byte[] CDSessionInfoResponse)
        {
            CDSessionInfo? decoded = Decode(CDSessionInfoResponse);

            return Prettify(decoded);
        }

        public struct CDSessionInfo
        {
            /// <summary>Total size of returned session information minus this field</summary>
            public ushort DataLength;
            /// <summary>First track number in hex</summary>
            public byte FirstCompleteSession;
            /// <summary>Last track number in hex</summary>
            public byte LastCompleteSession;
            /// <summary>Track descriptors</summary>
            public TrackDataDescriptor[] TrackDescriptors;
        }

        public struct TrackDataDescriptor
        {
            /// <summary>Byte 0 Reserved</summary>
            public byte Reserved1;
            /// <summary>Byte 1, bits 7 to 4 Type of information in Q subchannel of block where this TOC entry was found</summary>
            public byte ADR;
            /// <summary>Byte 1, bits 3 to 0 Track attributes</summary>
            public byte CONTROL;
            /// <summary>Byte 2 First track number in last complete session</summary>
            public byte TrackNumber;
            /// <summary>Byte 3 Reserved</summary>
            public byte Reserved2;
            /// <summary>Bytes 4 to 7 First track number in last complete session start address in LBA or in MSF</summary>
            public uint TrackStartAddress;
        }
    }
}