Aaru/Aaru.Core/Sidecar/Helpers.cs

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Helpers.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Core algorithms.
//
// --[ Description ] ----------------------------------------------------------
//
//     Contains helper logic used on sidecar creation.
//
// --[ 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 © 2011-2022 Natalia Portillo
// ****************************************************************************/

namespace Aaru.Core;

public sealed partial class Sidecar
{
    /// <summary>Converts a LBA to MM:SS:FF string for CDs</summary>
    /// <param name="lba">LBA</param>
    /// <returns>MM:SS:FF</returns>
    static string LbaToMsf(long lba)
    {
        long m, s, f;

        if(lba >= -150)
        {
            m   =  (lba + 150) / (75 * 60);
            lba -= m           * (75 * 60);
            s   =  (lba + 150) / 75;
            lba -= s           * 75;
            f   =  lba + 150;
        }
        else
        {
            m   =  (lba + 450150) / (75 * 60);
            lba -= m              * (75 * 60);
            s   =  (lba + 450150) / 75;
            lba -= s              * 75;
            f   =  lba + 450150;
        }

        return $"{m}:{s:D2}:{f:D2}";
    }

    /// <summary>Converts a LBA to MM:SS:FF string for DDCDs</summary>
    /// <param name="lba">LBA</param>
    /// <returns>MM:SS:FF</returns>
    static string DdcdLbaToMsf(long lba)
    {
        long h, m, s, f;

        if(lba >= -150)
        {
            h   =  (lba + 150) / (75 * 60 * 60);
            lba -= h           * (75 * 60 * 60);
            m   =  (lba + 150) / (75 * 60);
            lba -= m           * (75 * 60);
            s   =  (lba + 150) / 75;
            lba -= s           * 75;
            f   =  lba + 150;
        }
        else
        {
            h   =  (lba + 450150 * 2) / (75 * 60 * 60);
            lba -= h                  * (75 * 60 * 60);
            m   =  (lba + 450150 * 2) / (75 * 60);
            lba -= m                  * (75 * 60);
            s   =  (lba + 450150 * 2) / 75;
            lba -= s                  * 75;
            f   =  lba + 450150 * 2;
        }

        return string.Format("{3}:{0:D2}:{1:D2}:{2:D2}", m, s, f, h);
    }
}