// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : DiscInformation.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
//     Decodes MMC's GET DISC INFORMATION 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 © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Text;

namespace DiscImageChef.Decoders.SCSI.MMC
{
    /// <summary>
    /// 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
    /// </summary>
    public static class DiscInformation
    {
        public struct StandardDiscInformation
        {
            /// <summary>
            /// Bytes 0 to 1
            /// 32 + OPCTablesNumber*8
            /// </summary>
            public ushort DataLength;
            /// <summary>
            /// Byte 2, bits 7 to 5
            /// 000b
            /// </summary>
            public byte DataType;
            /// <summary>
            /// Byte 2, bit 4
            /// If set, disc is erasable
            /// </summary>
            public bool Erasable;
            /// <summary>
            /// Byte 2, bits 3 to 2
            /// Status of last session
            /// </summary>
            public byte LastSessionStatus;
            /// <summary>
            /// Byte 2, bits 1 to 0
            /// Status of disc
            /// </summary>
            public byte DiscStatus;
            /// <summary>
            /// Byte 3
            /// Number of logical track that contains LBA 0
            /// </summary>
            public byte FirstTrackNumber;
            /// <summary>
            /// Byte 9 (MSB) and byte 4 (LSB)
            /// Number of sessions
            /// </summary>
            public ushort Sessions;
            /// <summary>
            /// Byte 10 (MSB) and byte 5 (LSB)
            /// Number of first track in last session
            /// </summary>
            public ushort FirstTrackLastSession;
            /// <summary>
            /// Byte 11 (MSB) and byte 6 (LSB)
            /// Number of last track in last session
            /// </summary>
            public ushort LastTrackLastSession;
            /// <summary>
            /// Byte 7, bit 7
            /// If set, DiscIdentification is valid
            /// </summary>
            public bool DID_V;
            /// <summary>
            /// Byte 7, bit 6
            /// If set, DiscBarcode is valid
            /// </summary>
            public bool DBC_V;
            /// <summary>
            /// Byte 7, bit 5
            /// If set, disc is unrestricted
            /// </summary>
            public bool URU;
            /// <summary>
            /// Byte 7, bit 4
            /// If set DiscApplicationCode is valid
            /// </summary>
            public bool DAC_V;
            /// <summary>
            /// Byte 7, bit 3
            /// Reserved
            /// </summary>
            public bool Reserved;
            /// <summary>
            /// Byte 7, bit 2
            /// Copy of dirty bit from MRW status
            /// </summary>
            public bool Dbit;
            /// <summary>
            /// Byte 7, bits 1 to 0
            /// Background format status
            /// </summary>
            public byte BGFormatStatus;
            /// <summary>
            /// Byte 8
            /// Disc type code
            /// </summary>
            public byte DiscType;
            /// <summary>
            /// Bytes 12 to 15
            /// Disc identification number from PMA
            /// </summary>
            public uint DiscIdentification;
            /// <summary>
            /// Bytes 16 to 19
            /// Last Session Lead-in Start Address (MSF for CD, LBA for others)
            /// </summary>
            public uint LastSessionLeadInStartLBA;
            /// <summary>
            /// Bytes 20 to 23
            /// Last Possible Lead-out Start Address (MSF for CD, LBA for others)
            /// </summary>
            public uint LastPossibleLeadOutStartLBA;
            /// <summary>
            /// Bytes 24 to 31
            /// Disc barcode
            /// </summary>
            public ulong DiscBarcode;
            /// <summary>
            /// Byte 32
            /// Disc application code
            /// </summary>
            public byte DiscApplicationCode;
            /// <summary>
            /// Byte 33
            /// How many OPC tables are
            /// </summary>
            public byte OPCTablesNumber;
            /// <summary>
            /// Bytes 34 to end
            /// OPC tables (8 bytes each)
            /// </summary>
            public OPCTable[] OPCTables;
        }

        public struct OPCTable
        {
            /// <summary>
            /// Bytes 0 to 1
            /// kilobytes/sec this OPC table applies to
            /// </summary>
            public ushort Speed;
            /// <summary>
            /// Bytes 2 to 7
            /// OPC values
            /// </summary>
            public byte[] OPCValues;
        }

        public struct TrackResourcesInformation
        {
            /// <summary>
            /// Bytes 0 to 1
            /// 10
            /// </summary>
            public ushort DataLength;
            /// <summary>
            /// Byte 2, bits 7 to 5
            /// 001b
            /// </summary>
            public byte DataType;
            /// <summary>
            /// Byte 2, bits 4 to 0
            /// Reserved
            /// </summary>
            public byte Reserved1;
            /// <summary>
            /// Byte 3
            /// Reserved
            /// </summary>
            public byte Reserved2;
            /// <summary>
            /// Bytes 4 to 5
            /// Maximum possible number of the tracks on the disc
            /// </summary>
            public ushort MaxTracks;
            /// <summary>
            /// Bytes 6 to 7
            /// Number of the assigned tracks on the disc
            /// </summary>
            public ushort AssignedTracks;
            /// <summary>
            /// Bytes 8 to 9
            /// Maximum possible number of appendable tracks on the disc
            /// </summary>
            public ushort MaxAppendableTracks;
            /// <summary>
            /// Bytes 10 to 11
            /// Current number of appendable tracks on the disc
            /// </summary>
            public ushort AppendableTracks;
        }

        public struct POWResourcesInformation
        {
            /// <summary>
            /// Bytes 0 to 1
            /// 14
            /// </summary>
            public ushort DataLength;
            /// <summary>
            /// Byte 2, bits 7 to 5
            /// 010b
            /// </summary>
            public byte DataType;
            /// <summary>
            /// Byte 2, bits 4 to 0
            /// Reserved
            /// </summary>
            public byte Reserved1;
            /// <summary>
            /// Byte 3
            /// Reserved
            /// </summary>
            public byte Reserved2;
            /// <summary>
            /// Bytes 4 to 7
            /// Remaining POW replacements
            /// </summary>
            public uint RemainingPOWReplacements;
            /// <summary>
            /// Bytes 8 to 11
            /// Remaining POW reallocation map entries
            /// </summary>
            public uint RemainingPOWReallocation;
            /// <summary>
            /// Bytes 12 to 15
            /// Number of remaining POW updates
            /// </summary>
            public uint RemainingPOWUpdates;
        }

        public static StandardDiscInformation? Decode000b(byte[] response)
        {
            if(response.Length < 34) return null;

            if((response[2] & 0xE0) != 0) return null;

            StandardDiscInformation decoded = new StandardDiscInformation();
            decoded.DataLength = (ushort)((response[0] << 8) + response[1]);

            if(decoded.DataLength + 2 != response.Length) return null;

            decoded.DataType = (byte)((response[2] & 0xE0) >> 5);
            decoded.Erasable |= (response[2] & 0x10) == 0x10;
            decoded.LastSessionStatus = (byte)((response[2] & 0x0C) >> 2);
            decoded.DiscStatus = (byte)(response[2] & 0x03);
            decoded.FirstTrackNumber = response[3];
            decoded.Sessions = (ushort)((response[9] << 8) + response[4]);
            decoded.FirstTrackLastSession = (ushort)((response[10] << 8) + response[5]);
            decoded.LastTrackLastSession = (ushort)((response[11] << 8) + response[6]);

            decoded.DID_V |= (response[7] & 0x80) == 0x80;
            decoded.DBC_V |= (response[7] & 0x40) == 0x40;
            decoded.URU |= (response[7] & 0x20) == 0x20;
            decoded.DAC_V |= (response[7] & 0x10) == 0x10;
            decoded.Reserved |= (response[7] & 0x08) == 0x08;
            decoded.Dbit |= (response[7] & 0x04) == 0x04;
            decoded.BGFormatStatus = (byte)(response[7] & 0x03);

            decoded.DiscIdentification =
                (uint)((response[12] << 24) + (response[13] << 16) + (response[14] << 8) + response[15]);
            decoded.LastSessionLeadInStartLBA =
                (uint)((response[16] << 24) + (response[17] << 16) + (response[18] << 8) + response[19]);
            decoded.LastPossibleLeadOutStartLBA =
                (uint)((response[20] << 24) + (response[21] << 16) + (response[22] << 8) + response[23]);

            byte[] temp = new byte[8];
            Array.Copy(response, 24, temp, 0, 8);
            Array.Reverse(temp);
            decoded.DiscBarcode = BitConverter.ToUInt64(temp, 0);

            decoded.DiscApplicationCode = response[32];
            decoded.OPCTablesNumber = response[33];

            if(decoded.OPCTablesNumber <= 0 || response.Length != decoded.OPCTablesNumber * 8 + 34) return decoded;

            decoded.OPCTables = new OPCTable[decoded.OPCTablesNumber];
            for(int i = 0; i < decoded.OPCTablesNumber; i++)
            {
                decoded.OPCTables[i].Speed = (ushort)((response[34 + i * 8 + 0] << 16) + response[34 + i * 8 + 1]);
                decoded.OPCTables[i].OPCValues = new byte[6];
                Array.Copy(response, 34 + i * 8 + 2, decoded.OPCTables[i].OPCValues, 0, 6);
            }

            return decoded;
        }

        public static string Prettify000b(StandardDiscInformation? information)
        {
            if(!information.HasValue) return null;

            StandardDiscInformation decoded = information.Value;

            if(decoded.DataType != 0) return null;

            StringBuilder sb = new StringBuilder();

            switch(decoded.DiscType)
            {
                case 0x00:
                    sb.AppendLine("Disc type declared as CD-DA or CD-ROM");
                    break;
                case 0x10:
                    sb.AppendLine("Disc type declared as CD-i");
                    break;
                case 0x20:
                    sb.AppendLine("Disc type declared as CD-ROM XA");
                    break;
                case 0xFF:
                    sb.AppendLine("Disc type is undefined");
                    break;
                default:
                    sb.AppendFormat("Unknown disc type {0:X2}h", decoded.DiscType).AppendLine();
                    break;
            }

            switch(decoded.DiscStatus)
            {
                case 0:
                    sb.AppendLine("Disc is empty");
                    break;
                case 1:
                    sb.AppendLine("Disc is incomplete");
                    break;
                case 2:
                    sb.AppendLine("Disc is finalized");
                    break;
            }

            if(decoded.Erasable) sb.AppendLine("Disc is erasable");

            switch(decoded.LastSessionStatus)
            {
                case 0:
                    sb.AppendLine("Last session is empty");
                    break;
                case 1:
                    sb.AppendLine("Last session is incomplete");
                    break;
                case 2:
                    sb.AppendLine("Last session is damaged");
                    break;
                case 3:
                    sb.AppendLine("Last session is complete");
                    break;
            }

            switch(decoded.BGFormatStatus)
            {
                case 1:
                    sb.AppendLine("Media was being formatted in the background but it is stopped and incomplete");
                    break;
                case 2:
                    sb.AppendLine("Media is currently being formatted in the background");
                    break;
                case 3:
                    sb.AppendLine("Media background formatting has completed");
                    break;
            }

            if(decoded.Dbit) sb.AppendLine("MRW is dirty");

            sb.AppendFormat("First track on disc is track {0}", decoded.FirstTrackNumber).AppendLine();
            sb.AppendFormat("Disc has {0} sessions", decoded.Sessions).AppendLine();
            sb.AppendFormat("First track in last session is track {0}", decoded.FirstTrackLastSession).AppendLine();
            sb.AppendFormat("Last track in last session is track {0}", decoded.LastTrackLastSession).AppendLine();
            sb.AppendFormat("Last session Lead-In address is {0} (as LBA) or {1:X2}:{2:X2}:{3:X2}",
                            decoded.LastSessionLeadInStartLBA, (decoded.LastSessionLeadInStartLBA & 0xFF0000) >> 16,
                            (decoded.LastSessionLeadInStartLBA & 0xFF00) >> 8,
                            decoded.LastSessionLeadInStartLBA & 0xFF).AppendLine();
            sb.AppendFormat("Last possible Lead-Out address is {0} (as LBA) or {1:X2}:{2:X2}:{3:X2}",
                            decoded.LastPossibleLeadOutStartLBA, (decoded.LastPossibleLeadOutStartLBA & 0xFF0000) >> 16,
                            (decoded.LastPossibleLeadOutStartLBA & 0xFF00) >> 8,
                            decoded.LastPossibleLeadOutStartLBA & 0xFF).AppendLine();

            if(decoded.URU) sb.AppendLine("Disc is defined for unrestricted use");
            else sb.AppendLine("Disc is defined for restricted use");

            if(decoded.DID_V) sb.AppendFormat("Disc ID: {0:X6}", decoded.DiscIdentification & 0x00FFFFFF).AppendLine();
            if(decoded.DBC_V) sb.AppendFormat("Disc barcode: {0:X16}", decoded.DiscBarcode).AppendLine();
            if(decoded.DAC_V) sb.AppendFormat("Disc application code: {0}", decoded.DiscApplicationCode).AppendLine();

            if(decoded.OPCTables == null) return sb.ToString();

            foreach(OPCTable table in decoded.OPCTables)
                sb.AppendFormat("OPC values for {0}Kbit/sec.: {1}, {2}, {3}, {4}, {5}, {6}", table.Speed,
                                table.OPCValues[0], table.OPCValues[1], table.OPCValues[2], table.OPCValues[3],
                                table.OPCValues[4], table.OPCValues[5]).AppendLine();

            return sb.ToString();
        }

        public static TrackResourcesInformation? Decode001b(byte[] response)
        {
            if(response.Length != 12) return null;

            if((response[2] & 0xE0) != 0x20) return null;

            TrackResourcesInformation decoded = new TrackResourcesInformation();
            decoded.DataLength = (ushort)((response[0] << 8) + response[1]);

            if(decoded.DataLength + 2 != response.Length) return null;

            decoded.DataType = (byte)((response[2] & 0xE0) >> 5);
            decoded.MaxTracks = (ushort)((response[4] << 8) + response[5]);
            decoded.AssignedTracks = (ushort)((response[6] << 8) + response[7]);
            decoded.MaxAppendableTracks = (ushort)((response[8] << 8) + response[9]);
            decoded.AppendableTracks = (ushort)((response[10] << 8) + response[11]);

            return decoded;
        }

        public static string Prettify001b(TrackResourcesInformation? information)
        {
            if(!information.HasValue) return null;

            TrackResourcesInformation decoded = information.Value;

            if(decoded.DataType != 1) return null;

            StringBuilder sb = new StringBuilder();

            sb.AppendFormat("{0} maximum possible tracks on the disc", decoded.MaxTracks).AppendLine();
            sb.AppendFormat("{0} assigned tracks on the disc", decoded.AssignedTracks).AppendLine();
            sb.AppendFormat("{0} maximum possible appendable tracks on the disc", decoded.AppendableTracks)
              .AppendLine();
            sb.AppendFormat("{0} current appendable tracks on the disc", decoded.MaxAppendableTracks).AppendLine();

            return sb.ToString();
        }

        public static POWResourcesInformation? Decode010b(byte[] response)
        {
            if(response.Length != 16) return null;

            if((response[2] & 0xE0) != 0x40) return null;

            POWResourcesInformation decoded = new POWResourcesInformation();
            decoded.DataLength = (ushort)((response[0] << 8) + response[1]);

            if(decoded.DataLength + 2 != response.Length) return null;

            decoded.DataType = (byte)((response[2] & 0xE0) >> 5);
            decoded.RemainingPOWReplacements =
                (ushort)((response[4] << 24) + (response[5] << 16) + (response[6] << 8) + response[7]);
            decoded.RemainingPOWReallocation =
                (ushort)((response[8] << 24) + (response[9] << 16) + (response[10] << 8) + response[11]);
            decoded.RemainingPOWUpdates =
                (ushort)((response[12] << 24) + (response[13] << 16) + (response[14] << 8) + response[15]);

            return decoded;
        }

        public static string Prettify010b(POWResourcesInformation? information)
        {
            if(!information.HasValue) return null;

            POWResourcesInformation decoded = information.Value;

            if(decoded.DataType != 1) return null;

            StringBuilder sb = new StringBuilder();

            sb.AppendFormat("{0} remaining POW replacements", decoded.RemainingPOWReplacements).AppendLine();
            sb.AppendFormat("{0} remaining POW reallocation map entries", decoded.RemainingPOWReallocation)
              .AppendLine();
            sb.AppendFormat("{0} remaining POW updates", decoded.RemainingPOWUpdates).AppendLine();

            return sb.ToString();
        }

        public static string Prettify(byte[] response)
        {
            if(response == null) return null;

            if(response.Length < 12) return null;

            switch(response[2] & 0xE0)
            {
                case 0x00: return Prettify000b(Decode000b(response));
                case 0x20: return Prettify001b(Decode001b(response));
                case 0x40: return Prettify010b(Decode010b(response));
            }

            return null;
        }
    }
}