// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Structs.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
//     Contains structures for Digital Research's DISKCOPY disk 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 © 2011-2025 Natalia Portillo
// ****************************************************************************/

using System.Runtime.InteropServices;

namespace Aaru.Images;

public sealed partial class DriDiskCopy
{
#region Nested type: Bpb

    [StructLayout(LayoutKind.Sequential, Pack = 1)]
    struct Bpb
    {
        /// <summary>Seems to be always 0x05</summary>
        public byte five;
        /// <summary>A drive code that corresponds (but it not equal to) CMOS drive types</summary>
        public DriveCode _driveCode;
        /// <summary>Unknown seems to be always 2</summary>
        public readonly ushort unknown;
        /// <summary>Cylinders</summary>
        public ushort cylinders;
        /// <summary>Seems to always be 0</summary>
        public readonly byte unknown2;
        /// <summary>Bytes per sector</summary>
        public ushort bps;
        /// <summary>Sectors per cluster</summary>
        public readonly byte spc;
        /// <summary>Sectors between BPB and FAT</summary>
        public readonly ushort rsectors;
        /// <summary>How many FATs</summary>
        public readonly byte fats_no;
        /// <summary>Entries in root directory</summary>
        public readonly ushort root_entries;
        /// <summary>Total sectors</summary>
        public ushort sectors;
        /// <summary>Media descriptor</summary>
        public readonly byte media_descriptor;
        /// <summary>Sectors per FAT</summary>
        public readonly ushort spfat;
        /// <summary>Sectors per track</summary>
        public ushort sptrack;
        /// <summary>Heads</summary>
        public ushort heads;
        /// <summary>Hidden sectors before BPB</summary>
        public readonly uint hsectors;
        /// <summary>Drive number</summary>
        public readonly byte drive_no;
        /// <summary>Seems to be 0</summary>
        public readonly ulong unknown3;
        /// <summary>Seems to be 0</summary>
        public readonly byte unknown4;
        /// <summary>Sectors per track (again?)</summary>
        public ushort sptrack2;
        /// <summary>Seems to be 0</summary>
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 144)]
        public byte[] unknown5;
    }

#endregion

#region Nested type: Footer

    [StructLayout(LayoutKind.Sequential, Pack = 1)]
    struct Footer
    {
        /// <summary>Signature: "DiskImage 2.01 (C) 1990,1991 Digital Research Inc\0"</summary>
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 51)]
        public byte[] signature;
        /// <summary>Information about the disk image, mostly imitates FAT BPB</summary>
        public Bpb bpb;
        /// <summary>Information about the disk image, mostly imitates FAT BPB, copy</summary>
        public Bpb bpbcopy;
    }

#endregion
}