// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : DDS.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Device structures decoders.
//
// --[ Description ] ----------------------------------------------------------
//
//     Decodes DVD Disc Definition Structure.
//
// --[ 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 © 2011-2026 Natalia Portillo
// ****************************************************************************/

using System;
using System.Diagnostics.CodeAnalysis;
using System.Text;

namespace Aaru.Decoders.DVD;

// 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
// ECMA 272: 120 mm DVD Rewritable Disk (DVD-RAM)
// ECMA 330: 120 mm (4,7 Gbytes per side) and 80 mm (1,46 Gbytes per side) DVD Rewritable Disk (DVD-RAM)
[SuppressMessage("ReSharper", "InconsistentNaming")]
[SuppressMessage("ReSharper", "MemberCanBeInternal")]
[SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
[SuppressMessage("ReSharper", "NotAccessedField.Global")]
public static class DDS
{
    public static DiscDefinitionStructure? Decode(byte[] response)
    {
        if(response?.Length != 2052) return null;

        var dds = new DiscDefinitionStructure
        {
            Identifier = (ushort)((response[4] << 8) + response[5])
        };

        if(dds.Identifier != 0x0A0A) return null;

        // Common to both DVD-RAM versions
        dds.DataLength                =  (ushort)((response[0] << 8) + response[1]);
        dds.Reserved1                 =  response[2];
        dds.Reserved2                 =  response[3];
        dds.Reserved3                 =  response[6];
        dds.InProcess                 |= (response[7] & 0x80) == 0x80;
        dds.UserCertification         |= (response[7] & 0x02) == 0x02;
        dds.ManufacturerCertification |= (response[7] & 0x01) == 0x01;

        dds.UpdateCount = (uint)((response[8] << 24) + (response[9] << 16) + (response[10] << 8) + response[11]);

        dds.Groups = (ushort)((response[12] << 8) + response[13]);

        // ECMA-272
        if(dds.Groups == 24)
        {
            dds.PartialCertification |= (response[7] & 0x40) == 0x40;
            dds.FormattingOnlyAGroup |= (response[7] & 0x20) == 0x20;
            dds.Reserved4            =  (byte)((response[7] & 0x1C) >> 2);
            dds.Reserved             =  new byte[6];
            Array.Copy(response, 14, dds.Reserved, 0, 6);
            dds.GroupCertificationFlags = new GroupCertificationFlag[24];

            for(var i = 0; i < 24; i++)
            {
                dds.GroupCertificationFlags[i].InProcess            |= (response[20 + i] & 0x80) == 0x80;
                dds.GroupCertificationFlags[i].PartialCertification |= (response[20 + i] & 0x40) == 0x40;
                dds.GroupCertificationFlags[i].Reserved1            =  (byte)((response[20 + i] & 0x3C) >> 2);
                dds.GroupCertificationFlags[i].UserCertification    |= (response[20 + i] & 0x02) == 0x02;
                dds.GroupCertificationFlags[i].Reserved2            |= (response[20 + i] & 0x01) == 0x01;
            }
        }

        // ECMA-330
        if(dds.Groups != 1) return dds;

        {
            dds.Reserved4 = (byte)((response[7] & 0x7C) >> 2);
            dds.Reserved  = new byte[68];
            Array.Copy(response, 16, dds.Reserved, 0, 68);
            dds.Zones             = (ushort)((response[14] << 8)  + response[15]);
            dds.SpareAreaFirstPSN = (uint)((response[85]   << 16) + (response[86] << 8) + response[87]);
            dds.SpareAreaLastPSN  = (uint)((response[89]   << 16) + (response[90] << 8) + response[91]);
            dds.LSN0Location      = (uint)((response[93]   << 16) + (response[94] << 8) + response[95]);
            dds.StartLSNForZone   = new uint[dds.Zones];

            for(var i = 0; i < dds.Zones; i++)
            {
                dds.StartLSNForZone[i] = (uint)((response[260 + i * 4 + 1] << 16) +
                                                (response[260 + i * 4 + 2] << 8)  +
                                                response[260 + i * 4 + 3]);
            }
        }

        return dds;
    }

    public static string Prettify(DiscDefinitionStructure? dds)
    {
        if(dds == null) return null;

        DiscDefinitionStructure decoded = dds.Value;
        var                     sb      = new StringBuilder();

        if(decoded.InProcess)
        {
            sb.AppendLine(Localization.Formatting_in_progress);

            if(decoded.Groups == 24)
            {
                if(decoded.PartialCertification)
                    sb.AppendLine(Localization.Formatting_is_only_using_partial_certification);

                if(decoded.FormattingOnlyAGroup) sb.AppendLine(Localization.Only_a_group_is_being_formatted);
            }
        }

        if(decoded.UserCertification) sb.AppendLine(Localization.Disc_has_been_certified_by_a_user);

        if(decoded.ManufacturerCertification) sb.AppendLine(Localization.Disc_has_been_certified_by_a_manufacturer);

        sb.AppendFormat(Localization.DDS_has_been_updated_0_times, decoded.UpdateCount).AppendLine();

        if(decoded.Groups == 24)
        {
            for(var i = 0; i < decoded.GroupCertificationFlags.Length; i++)
            {
                if(decoded.GroupCertificationFlags[i].InProcess)
                {
                    sb.AppendFormat(Localization.Group_0_is_being_formatted, i).AppendLine();

                    if(decoded.GroupCertificationFlags[i].PartialCertification)
                        sb.AppendFormat(Localization.Group_0_is_being_certified_partially, i).AppendLine();
                }

                if(decoded.GroupCertificationFlags[i].UserCertification)
                    sb.AppendFormat(Localization.Group_0_has_been_certified_by_an_user, i).AppendLine();
            }
        }

        if(decoded.Groups != 1) return sb.ToString();

        {
            sb.AppendFormat(Localization.Disc_has_0_zones, decoded.Zones).AppendLine();

            sb.AppendFormat(Localization.Primary_Spare_Area_stats_at_PSN_0_and_ends_at_PSN_1_inclusively,
                            decoded.SpareAreaFirstPSN,
                            decoded.SpareAreaLastPSN)
              .AppendLine();

            sb.AppendFormat(Localization.LSN_zero_is_at_PSN_0, decoded.LSN0Location).AppendLine();

            for(var i = 0; i < decoded.StartLSNForZone.Length; i++)
                sb.AppendFormat(Localization.Zone_0_starts_at_LSN_1, i, decoded.StartLSNForZone[i]).AppendLine();
        }

        return sb.ToString();
    }

    public static string Prettify(byte[] response) => Prettify(Decode(response));

#region Nested type: DiscDefinitionStructure

    public struct DiscDefinitionStructure
    {
        /// <summary>Bytes 0 to 1 Data length</summary>
        public ushort DataLength;
        /// <summary>Byte 2 Reserved</summary>
        public byte Reserved1;
        /// <summary>Byte 3 Reserved</summary>
        public byte Reserved2;

        /// <summary>Bytes 4 to 5 DDS Identifier = 0x0A0A</summary>
        public ushort Identifier;
        /// <summary>Byte 6 Reserved</summary>
        public byte Reserved3;
        /// <summary>Byte 7, bit 7 If set, formatting is in process</summary>
        public bool InProcess;
        /// <summary>Byte 7, bit 6 If set, formatting is using partial certification Only in ECMA-272</summary>
        public bool PartialCertification;
        /// <summary>Byte 7, bit 5 If set, only a group is being formatted Only in ECMA-272</summary>
        public bool FormattingOnlyAGroup;
        /// <summary>Byte 7, bits 4 to 2 Reserved</summary>
        public byte Reserved4;
        /// <summary>Byte 7, bit 1 If set, disk has been certified by a user</summary>
        public bool UserCertification;
        /// <summary>Byte 7, bit 0 If set, disk has been certified by a manufacturer</summary>
        public bool ManufacturerCertification;
        /// <summary>Bytes 8 to 11 How many times the DDS has been updated</summary>
        public uint UpdateCount;
        /// <summary>Bytes 12 to 13 How many groups the disk has 24 for ECMA-272 1 for ECMA-330</summary>
        public ushort Groups;
        /// <summary>Bytes 14 to 15 How many zones the disk has Only in ECMA-330</summary>
        public ushort Zones;
        /// <summary>Bytes 14 to 19 in ECMA-272 Bytes 16 to 83 in ECMA-330 Reserved</summary>
        public byte[] Reserved;
        /// <summary>Bytes 20 to 43 Group certification flags</summary>
        public GroupCertificationFlag[] GroupCertificationFlags;

        /// <summary>Bytes 85 to 87 Location of first sector in the Primary Spare Area</summary>
        public uint SpareAreaFirstPSN;
        /// <summary>Bytes 89 to 91 Location of first sector in the Primary Spare Area</summary>
        public uint SpareAreaLastPSN;
        /// <summary>Bytes 93 to 95 PSN for LSN 0</summary>
        public uint LSN0Location;
        /// <summary>The starting LSN of each zone</summary>
        public uint[] StartLSNForZone;
    }

#endregion

#region Nested type: GroupCertificationFlag

    public struct GroupCertificationFlag
    {
        /// <summary>Bit 7 If set, formatting of this group is in process</summary>
        public bool InProcess;
        /// <summary>Bit 6 If set, formatting is using partial certification</summary>
        public bool PartialCertification;
        /// <summary>Bits 5 to 2 Reserved</summary>
        public byte Reserved1;
        /// <summary>Bit 1 If set, this group has been certified by user</summary>
        public bool UserCertification;
        /// <summary>Bit 0 Reserved</summary>
        public bool Reserved2;
    }

#endregion
}