// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : SS.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
//     Decodes Xbox security sectors
//
// --[ 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;
using DiscImageChef.Decoders.DVD;

namespace DiscImageChef.Decoders.Xbox
{
    public static class SS
    {
        public struct SecuritySector
        {
            /// <summary>
            /// Byte 0, bits 7 to 4
            /// Disk category field
            /// </summary>
            public DiskCategory DiskCategory;
            /// <summary>
            /// Byte 0, bits 3 to 0
            /// Media version
            /// </summary>
            public byte PartVersion;
            /// <summary>
            /// Byte 1, bits 7 to 4
            /// 120mm if 0, 80mm if 1. If UMD (60mm) 0 also. Reserved rest of values
            /// </summary>
            public DVDSize DiscSize;
            /// <summary>
            /// Byte 1, bits 3 to 0
            /// Maximum data rate
            /// </summary>
            public MaximumRateField MaximumRate;
            /// <summary>
            /// Byte 2, bit 7
            /// Reserved
            /// </summary>
            public bool Reserved3;
            /// <summary>
            /// Byte 2, bits 6 to 5
            /// Number of layers
            /// </summary>
            public byte Layers;
            /// <summary>
            /// Byte 2, bit 4
            /// Track path
            /// </summary>
            public bool TrackPath;
            /// <summary>
            /// Byte 2, bits 3 to 0
            /// Layer type
            /// </summary>
            public LayerTypeFieldMask LayerType;
            /// <summary>
            /// Byte 3, bits 7 to 4
            /// Linear density field
            /// </summary>
            public LinearDensityField LinearDensity;
            /// <summary>
            /// Byte 3, bits 3 to 0
            /// Track density field
            /// </summary>
            public TrackDensityField TrackDensity;
            /// <summary>
            /// Bytes 4 to 7
            /// PSN where Data Area starts
            /// </summary>
            public uint DataAreaStartPSN;
            /// <summary>
            /// Bytes 8 to 11
            /// PSN where Data Area ends
            /// </summary>
            public uint DataAreaEndPSN;
            /// <summary>
            /// Bytes 12 to 15
            /// PSN where Data Area ends in Layer 0
            /// </summary>
            public uint Layer0EndPSN;

            /// <summary>
            /// Byte 27
            /// Always 0x06 on XGD3
            /// </summary>
            public byte Unknown1;
            /// <summary>
            /// Bytes 256 to 283
            /// Unknown, XGD2 and XGD3
            /// </summary>
            public byte[] Unknown2;
            /// <summary>
            /// Bytes 284 to 719
            /// Unknown, XGD3
            /// </summary>
            public byte[] Unknown3;
            /// <summary>
            /// Bytes 720 to 723
            /// Unknown
            /// </summary>
            public byte[] Unknown4;
            /// <summary>
            /// Bytes 724 to 767
            /// Unknown, XGD3
            /// </summary>
            public byte[] Unknown5;
            /// <summary>
            /// Byte 768
            /// Version of challenge table
            /// </summary>
            public byte ChallengeTableVersion;
            /// <summary>
            /// Byte 769
            /// Number of challenge entries
            /// </summary>
            public byte NoChallengeEntries;
            /// <summary>
            /// Bytes 770 to 1022
            /// Unknown
            /// </summary>
            public ChallengeEntry[] ChallengeEntries;
            /// <summary>
            /// Byte 1023
            /// Unknown
            /// </summary>
            public byte Unknown6;
            /// <summary>
            /// Bytes 1052 to 1099
            /// Unknown, XGD1 only
            /// </summary>
            public byte[] Unknown7;
            /// <summary>
            /// Bytes 1120 to 1135
            /// Unknown, XGD2 and XGD3
            /// </summary>
            public byte[] Unknown8;
            /// <summary>
            /// Bytes 1180 to 1195
            /// Unknown
            /// </summary>
            public byte[] Unknown9;
            /// <summary>
            /// Bytes 1208 to 1511
            /// Unknown
            /// </summary>
            public byte[] Unknown10;
            /// <summary>
            /// Bytes 1528 to 1632
            /// </summary>
            public byte[] Unknown11;
            /// <summary>
            /// Bytes 1633 to 1839
            /// Security extents, 23 entries of 9 bytes
            /// </summary>
            public SecuritySectorExtent[] Extents;
            /// <summary>
            /// Bytes 1840 to 2047
            /// Copy of the security extents, 23 entries of 9 bytes
            /// </summary>
            public SecuritySectorExtent[] ExtentsCopy;
        }

        public struct SecuritySectorExtent
        {
            /// <summary>
            /// Bytes 0 to 2
            /// Unknown
            /// </summary>
            public uint Unknown;
            /// <summary>
            /// Bytes 3 to 5
            /// Start PSN of this security extent
            /// </summary>
            public uint StartPSN;
            /// <summary>
            /// Bytes 6 to 8
            /// End PSN of this security extent
            /// </summary>
            public uint EndPSN;
        }

        public struct ChallengeEntry
        {
            public byte Level;
            public byte ChallengeId;
            public uint ChallengeValue;
            public byte ResponseModifier;
            public uint ResponseValue;
        }

        public static SecuritySector? Decode(byte[] response)
        {
            if(response == null) return null;

            if(response.Length < 2048) return null;

            SecuritySector ss = new SecuritySector();

            // Common
            ss.DiskCategory = (DiskCategory)((response[0] & 0xF0) >> 4);
            ss.PartVersion = (byte)(response[0] & 0x0F);
            ss.DiscSize = (DVDSize)((response[1] & 0xF0) >> 4);
            ss.MaximumRate = (MaximumRateField)(response[1] & 0x0F);
            ss.Reserved3 |= (response[2] & 0x80) == 0x80;
            ss.Layers = (byte)((response[2] & 0x60) >> 5);
            ss.TrackPath |= (response[2] & 0x08) == 0x08;
            ss.LayerType = (LayerTypeFieldMask)(response[2] & 0x07);
            ss.LinearDensity = (LinearDensityField)((response[3] & 0xF0) >> 4);
            ss.TrackDensity = (TrackDensityField)(response[3] & 0x0F);
            ss.DataAreaStartPSN = (uint)((response[4] << 24) + (response[5] << 16) + (response[6] << 8) + response[7]);
            ss.DataAreaEndPSN = (uint)((response[8] << 24) + (response[9] << 16) + (response[10] << 8) + response[11]);
            ss.Layer0EndPSN = (uint)((response[12] << 24) + (response[13] << 16) + (response[14] << 8) + response[15]);

            ss.Unknown1 = response[27];
            ss.Unknown2 = new byte[28];
            Array.Copy(response, 256, ss.Unknown2, 0, 28);
            ss.Unknown3 = new byte[436];
            Array.Copy(response, 284, ss.Unknown3, 0, 436);
            ss.Unknown4 = new byte[4];
            Array.Copy(response, 720, ss.Unknown4, 0, 4);
            ss.Unknown5 = new byte[43];
            Array.Copy(response, 724, ss.Unknown5, 0, 43);
            ss.ChallengeTableVersion = response[768];
            ss.NoChallengeEntries = response[769];
            ss.ChallengeEntries = new ChallengeEntry[23];
            for(int i = 0; i < 23; i++)
            {
                ss.ChallengeEntries[i] = new ChallengeEntry();
                ss.ChallengeEntries[i].Level = response[770 + i * 11 + 0];
                ss.ChallengeEntries[i].ChallengeId = response[770 + i * 11 + 1];
                ss.ChallengeEntries[i].ChallengeValue =
                    (uint)((response[770 + i * 11 + 2] << 24) + (response[770 + i * 11 + 3] << 16) +
                           (response[770 + i * 11 + 4] << 8) + response[770 + i * 11 + 5]);
                ss.ChallengeEntries[i].ResponseModifier = response[770 + i * 11 + 6];
                ss.ChallengeEntries[i].ResponseValue =
                    (uint)((response[770 + i * 11 + 7] << 24) + (response[770 + i * 11 + 8] << 16) +
                           (response[770 + i * 11 + 9] << 8) + response[770 + i * 11 + 10]);
            }

            ss.Unknown6 = response[1023];
            ss.Unknown7 = new byte[48];
            Array.Copy(response, 1052, ss.Unknown7, 0, 48);
            ss.Unknown8 = new byte[16];
            Array.Copy(response, 1120, ss.Unknown8, 0, 16);
            ss.Unknown9 = new byte[16];
            Array.Copy(response, 1180, ss.Unknown9, 0, 16);
            ss.Unknown10 = new byte[303];
            Array.Copy(response, 1208, ss.Unknown10, 0, 303);
            ss.Unknown11 = new byte[104];
            Array.Copy(response, 1528, ss.Unknown11, 0, 104);
            ss.Extents = new SecuritySectorExtent[23];
            for(int i = 0; i < 23; i++)
            {
                ss.Extents[i] = new SecuritySectorExtent();
                ss.Extents[i].Unknown = (uint)((response[1633 + i * 9 + 0] << 16) + (response[1633 + i * 9 + 1] << 8) +
                                               response[1633 + i * 9 + 2]);
                ss.Extents[i].StartPSN = (uint)((response[1633 + i * 9 + 3] << 16) + (response[1633 + i * 9 + 4] << 8) +
                                                response[1633 + i * 9 + 5]);
                ss.Extents[i].EndPSN = (uint)((response[1633 + i * 9 + 6] << 16) + (response[1633 + i * 9 + 7] << 8) +
                                              response[1633 + i * 9 + 8]);
            }

            ss.ExtentsCopy = new SecuritySectorExtent[23];
            for(int i = 0; i < 23; i++)
            {
                ss.ExtentsCopy[i] = new SecuritySectorExtent();
                ss.ExtentsCopy[i].Unknown = (uint)((response[1840 + i * 9 + 0] << 16) +
                                                   (response[1840 + i * 9 + 1] << 8) + response[1840 + i * 9 + 2]);
                ss.ExtentsCopy[i].StartPSN = (uint)((response[1840 + i * 9 + 3] << 16) +
                                                    (response[1840 + i * 9 + 4] << 8) + response[1840 + i * 9 + 5]);
                ss.ExtentsCopy[i].EndPSN = (uint)((response[1840 + i * 9 + 6] << 16) +
                                                  (response[1840 + i * 9 + 7] << 8) + response[1840 + i * 9 + 8]);
            }

            return ss;
        }

        public static string Prettify(SecuritySector? ss)
        {
            if(ss == null) return null;

            SecuritySector decoded = ss.Value;
            StringBuilder sb = new StringBuilder();

            string sizeString;
            switch(decoded.DiscSize)
            {
                case DVDSize.Eighty:
                    sizeString = "80mm";
                    break;
                case DVDSize.OneTwenty:
                    sizeString = "120mm";
                    break;
                default:
                    sizeString = $"unknown size identifier {decoded.DiscSize}";
                    break;
            }

            string categorySentence = "Disc is a {0} {1} version {2}";

            switch(decoded.DiskCategory)
            {
                case DiskCategory.DVDPRWDL:
                    sb.AppendFormat(categorySentence, sizeString, "Xbox Game Disc", decoded.PartVersion).AppendLine();
                    break;
                case DiskCategory.DVDPRDL:
                    sb.AppendFormat(categorySentence, sizeString, "Xbox 360 Game Disc", decoded.PartVersion)
                      .AppendLine();
                    break;
                default:
                    sb.AppendFormat(categorySentence, sizeString, "unknown disc type", decoded.PartVersion)
                      .AppendLine();
                    break;
            }

            switch(decoded.MaximumRate)
            {
                case MaximumRateField.TwoMbps:
                    sb.AppendLine("Disc maximum transfer rate is 2,52 Mbit/sec.");
                    break;
                case MaximumRateField.FiveMbps:
                    sb.AppendLine("Disc maximum transfer rate is 5,04 Mbit/sec.");
                    break;
                case MaximumRateField.TenMbps:
                    sb.AppendLine("Disc maximum transfer rate is 10,08 Mbit/sec.");
                    break;
                case MaximumRateField.TwentyMbps:
                    sb.AppendLine("Disc maximum transfer rate is 20,16 Mbit/sec.");
                    break;
                case MaximumRateField.ThirtyMbps:
                    sb.AppendLine("Disc maximum transfer rate is 30,24 Mbit/sec.");
                    break;
                case MaximumRateField.Unspecified:
                    sb.AppendLine("Disc maximum transfer rate is unspecified.");
                    break;
                default:
                    sb.AppendFormat("Disc maximum transfer rate is specified by unknown key {0}", decoded.MaximumRate)
                      .AppendLine();
                    break;
            }

            sb.AppendFormat("Disc has {0} layers", decoded.Layers + 1).AppendLine();
            if(decoded.TrackPath && decoded.Layers == 1) sb.AppendLine("Layers are in parallel track path");
            else if(!decoded.TrackPath && decoded.Layers == 1) sb.AppendLine("Layers are in opposite track path");

            switch(decoded.LinearDensity)
            {
                case LinearDensityField.TwoSix:
                    sb.AppendLine("Pitch size is 0,267 μm/bit");
                    break;
                case LinearDensityField.TwoNine:
                    sb.AppendLine("Pitch size is 0,147 μm/bit");
                    break;
                case LinearDensityField.FourZero:
                    sb.AppendLine("Pitch size is between 0,409 μm/bit and 0,435 μm/bit");
                    break;
                case LinearDensityField.TwoEight:
                    sb.AppendLine("Pitch size is between 0,140 μm/bit and 0,148 μm/bit");
                    break;
                case LinearDensityField.OneFive:
                    sb.AppendLine("Pitch size is 0,153 μm/bit");
                    break;
                case LinearDensityField.OneThree:
                    sb.AppendLine("Pitch size is between 0,130 μm/bit and 0,140 μm/bit");
                    break;
                case LinearDensityField.ThreeFive:
                    sb.AppendLine("Pitch size is 0,353 μm/bit");
                    break;
                default:
                    sb.AppendFormat("Unknown pitch size key {0}", decoded.LinearDensity).AppendLine();
                    break;
            }

            switch(decoded.TrackDensity)
            {
                case TrackDensityField.Seven:
                    sb.AppendLine("Track size is 0,74 μm");
                    break;
                case TrackDensityField.Eight:
                    sb.AppendLine("Track size is 0,80 μm");
                    break;
                case TrackDensityField.Six:
                    sb.AppendLine("Track size is 0,615 μm");
                    break;
                case TrackDensityField.Four:
                    sb.AppendLine("Track size is 0,40 μm");
                    break;
                case TrackDensityField.Three:
                    sb.AppendLine("Track size is 0,34 μm");
                    break;
                default:
                    sb.AppendFormat("Unknown track size key {0}", decoded.LinearDensity).AppendLine();
                    break;
            }

            if(decoded.DataAreaStartPSN > 0)
                if(decoded.DataAreaEndPSN > 0)
                {
                    sb.AppendFormat("Data area starts at PSN {0:X}h", decoded.DataAreaStartPSN).AppendLine();
                    sb.AppendFormat("Data area ends at PSN {0:X}h", decoded.DataAreaEndPSN).AppendLine();
                    if(decoded.Layers == 1 && !decoded.TrackPath)
                        sb.AppendFormat("Layer 0 ends at PSN {0:X}h", decoded.Layer0EndPSN).AppendLine();
                }
                else sb.AppendLine("Disc is empty");
            else sb.AppendLine("Disc is empty");

            sb.AppendLine("Challenges:");
            foreach(ChallengeEntry entry in decoded.ChallengeEntries)
            {
                sb.AppendFormat("\tChallenge ID: {0}", entry.ChallengeId).AppendLine();
                sb.AppendFormat("\tChallenge level: {0}", entry.Level).AppendLine();
                sb.AppendFormat("\tChallenge value: 0x{0:X8}", entry.ChallengeValue).AppendLine();
                sb.AppendFormat("\tResponse modifier: {0}", entry.ResponseModifier).AppendLine();
                sb.AppendFormat("\tResponse value: 0x{0:X8}", entry.ResponseValue).AppendLine();
            }

            for(int i = 0; i < 16; i++)
                sb.AppendFormat("Extent starts at PSN {0:X6}h and ends at PSN {1:X6}h", decoded.Extents[i].StartPSN,
                                decoded.Extents[i].EndPSN).AppendLine();

            return sb.ToString();
        }

        public static string Prettify(byte[] response)
        {
            return Prettify(Decode(response));
        }
    }
}