// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : QCOW2.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
//     Manages QEMU Copy-On-Write v2 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 © 2011-2026 Natalia Portillo
// ****************************************************************************/

using System.Collections.Generic;
using System.IO;
using Aaru.CommonTypes.Interfaces;
using Aaru.CommonTypes.Structs;

namespace Aaru.Images;

/// <inheritdoc />
/// <summary>Implements reading and writing QEMU's Copy On Write v2 and v3 disk images</summary>
public sealed partial class Qcow2 : IWritableImage
{
    const string               MODULE_NAME = "QCOW2 plugin";
    Dictionary<ulong, byte[]>  _clusterCache;
    int                        _clusterSectors;
    int                        _clusterSize;
    ImageInfo                  _imageInfo;
    Stream                     _imageStream;
    ulong                      _l1Mask;
    int                        _l1Shift;
    ulong[]                    _l1Table;
    int                        _l2Bits;
    ulong                      _l2Mask;
    int                        _l2Size;
    Dictionary<ulong, ulong[]> _l2TableCache;
    int                        _maxClusterCache;
    int                        _maxL2TableCache;
    Header                     _qHdr;
    ulong[]                    _refCountTable;
    Dictionary<ulong, byte[]>  _sectorCache;
    ulong                      _sectorMask;
    FileStream                 _writingStream;

    public Qcow2() => _imageInfo = new ImageInfo
    {
        ReadableSectorTags    = [],
        ReadableMediaTags     = [],
        HasPartitions         = false,
        HasSessions           = false,
        Version               = null,
        Application           = "QEMU",
        ApplicationVersion    = null,
        Creator               = null,
        Comments              = null,
        MediaManufacturer     = null,
        MediaModel            = null,
        MediaSerialNumber     = null,
        MediaBarcode          = null,
        MediaPartNumber       = null,
        MediaSequence         = 0,
        LastMediaSequence     = 0,
        DriveManufacturer     = null,
        DriveModel            = null,
        DriveSerialNumber     = null,
        DriveFirmwareRevision = null
    };
}