Aaru/Aaru.Core/Media/Info/CompactDisc.cs

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : CompactDisc.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Core.
//
// --[ Description ] ----------------------------------------------------------
//
//     Retrieves information from CompactDisc media.
//
// --[ License ] --------------------------------------------------------------
//
//     This program is free software: you can redistribute it and/or modify
//     it under the terms of the GNU General Public License as
//     published by the Free Software Foundation, either version 3 of the
//     License, or (at your option) any later version.
//
//     This program 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 General Public License for more details.
//
//     You should have received a copy of the GNU General Public License
//     along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2025 Natalia Portillo
// ****************************************************************************/

using System;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using Aaru.CommonTypes;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Structs;
using Aaru.Core.Media.Detection;
using Aaru.Database.Models;
using Aaru.Decoders.CD;
using Aaru.Devices;
using Device = Aaru.Database.Models.Device;

namespace Aaru.Core.Media.Info;

/// <summary>Core operations for retrieving information about CD based media</summary>
public static class CompactDisc
{
    /// <summary>Gets the offset bytes from a Compact Disc</summary>
    /// <param name="cdOffset">Offset entry from database</param>
    /// <param name="dbDev">Device entry from database</param>
    /// <param name="debug">Debug</param>
    /// <param name="dev">Opened device</param>
    /// <param name="dskType">Detected disk type</param>
    /// <param name="dumpLog">Dump log if applicable</param>
    /// <param name="tracks">Disc track list</param>
    /// <param name="updateStatus">UpdateStatus event</param>
    /// <param name="driveOffset">Drive offset</param>
    /// <param name="combinedOffset">Combined offset</param>
    /// <param name="supportsPlextorReadCdDa">Set to <c>true</c> if drive supports PLEXTOR READ CD-DA vendor command</param>
    /// <returns><c>true</c> if offset could be found, <c>false</c> otherwise</returns>
    [SuppressMessage("ReSharper", "TooWideLocalVariableScope")]
    public static void GetOffset(CdOffset  cdOffset,    Device   dbDev,          bool debug, Aaru.Devices.Device dev,
                                 MediaType dskType,     Track[]  tracks,         UpdateStatusHandler updateStatus,
                                 out int?  driveOffset, out int? combinedOffset, out bool supportsPlextorReadCdDa)
    {
        byte[]     cmdBuf;
        bool       sense;
        int        minute;
        int        second;
        int        frame;
        byte[]     sectorSync;
        byte[]     tmpBuf;
        int        lba;
        int        diff;
        Track      dataTrack   = default;
        Track      audioTrack  = default;
        bool       offsetFound = false;
        const uint sectorSize  = 2352;
        driveOffset             = cdOffset?.Offset * 4;
        combinedOffset          = null;
        supportsPlextorReadCdDa = false;

        if(dskType != MediaType.VideoNowColor)
        {
            if(tracks.Any(t => t.Type != TrackType.Audio))
            {
                dataTrack = tracks.FirstOrDefault(t => t.Type != TrackType.Audio);

                if(dataTrack != null)
                {
                    // Build sync
                    sectorSync = [0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00];

                    tmpBuf = new byte[sectorSync.Length];

                    // Ensure to be out of the pregap, or multi-session discs give funny values
                    uint wantedLba = (uint)(dataTrack.StartSector + 151);

                    // Plextor READ CDDA
                    if(dbDev?.ATAPI?.RemovableMedias?.Any(d => d.SupportsPlextorReadCDDA == true) == true ||
                       dbDev?.SCSI?.RemovableMedias?.Any(d => d.SupportsPlextorReadCDDA  == true) == true ||
                       dev.Manufacturer.Equals("plextor", StringComparison.InvariantCultureIgnoreCase))
                    {
                        sense = dev.PlextorReadCdDa(out cmdBuf,
                                                    out _,
                                                    wantedLba,
                                                    sectorSize,
                                                    3,
                                                    PlextorSubchannel.None,
                                                    dev.Timeout,
                                                    out _);

                        if(!sense && !dev.Error)
                        {
                            supportsPlextorReadCdDa = true;

                            for(int i = 0; i < cmdBuf.Length - sectorSync.Length; i++)
                            {
                                Array.Copy(cmdBuf, i, tmpBuf, 0, sectorSync.Length);

                                if(!tmpBuf.SequenceEqual(sectorSync)) continue;

                                // De-scramble M and S
                                minute = cmdBuf[i + 12] ^ 0x01;
                                second = cmdBuf[i + 13] ^ 0x80;
                                frame  = cmdBuf[i + 14];

                                // Convert to binary
                                minute = minute / 16 * 10 + (minute & 0x0F);
                                second = second / 16 * 10 + (second & 0x0F);
                                frame  = frame  / 16 * 10 + (frame  & 0x0F);

                                // Calculate the first found LBA
                                lba = minute * 60 * 75 + second * 75 + frame - 150;

                                // Calculate the difference between the found LBA and the requested one
                                diff = (int)wantedLba - lba;

                                combinedOffset = i + 2352 * diff;
                                offsetFound    = true;

                                break;
                            }
                        }
                    }

                    if(!offsetFound &&
                       (debug                                                                                      ||
                        dbDev?.ATAPI?.RemovableMedias?.Any(d => d.CanReadCdScrambled              == true) == true ||
                        dbDev?.SCSI?.RemovableMedias?.Any(d => d.CanReadCdScrambled               == true) == true ||
                        dbDev?.SCSI?.MultiMediaDevice?.TestedMedia?.Any(d => d.CanReadCdScrambled == true) == true ||
                        dev.Manufacturer.Equals("hl-dt-st", StringComparison.InvariantCultureIgnoreCase)))
                    {
                        sense = dev.ReadCd(out cmdBuf,
                                           out _,
                                           wantedLba,
                                           sectorSize,
                                           3,
                                           MmcSectorTypes.Cdda,
                                           false,
                                           false,
                                           false,
                                           MmcHeaderCodes.None,
                                           true,
                                           false,
                                           MmcErrorField.None,
                                           MmcSubchannel.None,
                                           dev.Timeout,
                                           out _);

                        if(!sense && !dev.Error)
                        {
                            // Clear cache
                            for(int i = 0; i < 63; i++)
                            {
                                sense = dev.ReadCd(out _,
                                                   out _,
                                                   (uint)(wantedLba + 3 + 16 * i),
                                                   sectorSize,
                                                   16,
                                                   MmcSectorTypes.AllTypes,
                                                   false,
                                                   false,
                                                   false,
                                                   MmcHeaderCodes.None,
                                                   true,
                                                   false,
                                                   MmcErrorField.None,
                                                   MmcSubchannel.None,
                                                   dev.Timeout,
                                                   out _);

                                if(sense || dev.Error) break;
                            }

                            dev.ReadCd(out cmdBuf,
                                       out _,
                                       wantedLba,
                                       sectorSize,
                                       3,
                                       MmcSectorTypes.Cdda,
                                       false,
                                       false,
                                       false,
                                       MmcHeaderCodes.None,
                                       true,
                                       false,
                                       MmcErrorField.None,
                                       MmcSubchannel.None,
                                       dev.Timeout,
                                       out _);

                            for(int i = 0; i < cmdBuf.Length - sectorSync.Length; i++)
                            {
                                Array.Copy(cmdBuf, i, tmpBuf, 0, sectorSync.Length);

                                if(!tmpBuf.SequenceEqual(sectorSync)) continue;

                                // De-scramble M and S
                                minute = cmdBuf[i + 12] ^ 0x01;
                                second = cmdBuf[i + 13] ^ 0x80;
                                frame  = cmdBuf[i + 14];

                                // Convert to binary
                                minute = minute / 16 * 10 + (minute & 0x0F);
                                second = second / 16 * 10 + (second & 0x0F);
                                frame  = frame  / 16 * 10 + (frame  & 0x0F);

                                // Calculate the first found LBA
                                lba = minute * 60 * 75 + second * 75 + frame - 150;

                                // Calculate the difference between the found LBA and the requested one
                                diff = (int)wantedLba - lba;

                                combinedOffset = i + 2352 * diff;
                                offsetFound    = true;

                                break;
                            }
                        }
                    }
                }
            }

            if(offsetFound) return;

            // Try to get another the offset some other way, we need an audio track just after a data track, same session

            for(int i = 1; i < tracks.Length; i++)
            {
                if(tracks[i - 1].Type == TrackType.Audio || tracks[i].Type != TrackType.Audio) continue;

                dataTrack  = tracks[i - 1];
                audioTrack = tracks[i];

                break;
            }

            if(dataTrack is null || audioTrack is null) return;

            // Found them
            sense = dev.ReadCd(out cmdBuf,
                               out _,
                               (uint)audioTrack.StartSector,
                               sectorSize,
                               3,
                               MmcSectorTypes.Cdda,
                               false,
                               false,
                               false,
                               MmcHeaderCodes.None,
                               true,
                               false,
                               MmcErrorField.None,
                               MmcSubchannel.None,
                               dev.Timeout,
                               out _);

            if(sense || dev.Error) return;

            dataTrack.EndSector += 150;

            // Calculate MSF
            minute = (int)dataTrack.EndSector                   / 4500;
            second = ((int)dataTrack.EndSector - minute * 4500) / 75;
            frame  = (int)dataTrack.EndSector - minute * 4500 - second * 75;

            dataTrack.EndSector -= 150;

            // Convert to BCD
            minute = (minute / 10 << 4) + minute % 10;
            second = (second / 10 << 4) + second % 10;
            frame  = (frame  / 10 << 4) + frame  % 10;

            // Scramble M and S
            minute ^= 0x01;
            second ^= 0x80;

            // Build sync
            sectorSync =
            [
                0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, (byte)minute, (byte)second,
                (byte)frame
            ];

            tmpBuf = new byte[sectorSync.Length];

            for(int i = 0; i < cmdBuf.Length - sectorSync.Length; i++)
            {
                Array.Copy(cmdBuf, i, tmpBuf, 0, sectorSync.Length);

                if(!tmpBuf.SequenceEqual(sectorSync)) continue;

                combinedOffset = i + 2352;
                offsetFound    = true;

                break;
            }

            if(offsetFound || audioTrack.Pregap <= 0) return;

            sense = dev.ReadCd(out byte[] dataBuf,
                               out _,
                               (uint)dataTrack.EndSector,
                               sectorSize,
                               1,
                               MmcSectorTypes.AllTypes,
                               false,
                               false,
                               true,
                               MmcHeaderCodes.AllHeaders,
                               true,
                               true,
                               MmcErrorField.None,
                               MmcSubchannel.None,
                               dev.Timeout,
                               out _);

            if(sense || dev.Error) return;

            for(int i = 0; i < dataBuf.Length; i++) dataBuf[i] ^= Sector.ScrambleTable[i];

            for(int i = 0; i < 2352; i++)
            {
                byte[] dataSide  = new byte[2352 - i];
                byte[] audioSide = new byte[2352 - i];

                Array.Copy(dataBuf, i, dataSide,  0, dataSide.Length);
                Array.Copy(cmdBuf,  0, audioSide, 0, audioSide.Length);

                if(!dataSide.SequenceEqual(audioSide)) continue;

                combinedOffset = audioSide.Length;

                break;
            }
        }
        else
        {
            byte[] videoNowColorFrame = new byte[9 * sectorSize];

            sense = dev.ReadCd(out cmdBuf,
                               out _,
                               0,
                               sectorSize,
                               9,
                               MmcSectorTypes.AllTypes,
                               false,
                               false,
                               true,
                               MmcHeaderCodes.AllHeaders,
                               true,
                               true,
                               MmcErrorField.None,
                               MmcSubchannel.None,
                               dev.Timeout,
                               out _);

            if(sense || dev.Error)
            {
                sense = dev.ReadCd(out cmdBuf,
                                   out _,
                                   0,
                                   sectorSize,
                                   9,
                                   MmcSectorTypes.Cdda,
                                   false,
                                   false,
                                   true,
                                   MmcHeaderCodes.None,
                                   true,
                                   true,
                                   MmcErrorField.None,
                                   MmcSubchannel.None,
                                   dev.Timeout,
                                   out _);

                if(sense || dev.Error) videoNowColorFrame = null;
            }

            if(videoNowColorFrame is null)
                updateStatus?.Invoke(Localization.Core.Could_not_find_VideoNow_Color_frame_offset);
            else
            {
                combinedOffset = MMC.GetVideoNowColorOffset(videoNowColorFrame);

                updateStatus?.Invoke(string.Format(Localization.Core.VideoNow_Color_frame_is_offset_0_bytes,
                                                   combinedOffset));
            }
        }
    }
}