// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Optical.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : SCSI Block Commands.
//
// --[ Description ] ----------------------------------------------------------
//
//     Contains SCSI commands for optical memory devices.
//
// --[ 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 © 2011-2021 Natalia Portillo
// ****************************************************************************/

using System;
using Aaru.Console;
using Aaru.Decoders.SCSI;

namespace Aaru.Devices
{
    public sealed partial class Device
    {
        /// <summary>Scan the medium for a contiguous set of written or blank logical blocks</summary>
        /// <param name="senseBuffer">Sense buffer.</param>
        /// <param name="relAddr">Set to <c>true</c> if <paramref name="lba" /> is relative</param>
        /// <param name="lba">Logical block address where to start the search.</param>
        /// <param name="scanLength">Number of blocks to scan</param>
        /// <param name="foundBlocks">How many blocks were found</param>
        /// <param name="timeout">Timeout.</param>
        /// <param name="duration">Duration.</param>
        /// <param name="written">
        ///     If set to <c>true</c> drive will search for written blocks, otherwise it will search for blank
        ///     blocks
        /// </param>
        /// <param name="advancedScan">If set to <c>true</c> drive will consider the search area has contiguous blocks</param>
        /// <param name="reverse">If set to <c>true</c> drive will search in reverse</param>
        /// <param name="partial">
        ///     If set to <c>true</c> return even if the total number of blocks requested is not found but the
        ///     other parameters are met
        /// </param>
        /// <param name="requested">Number of contiguous blocks to find</param>
        /// <param name="foundLba">First LBA found</param>
        public bool MediumScan(out byte[] senseBuffer, bool written, bool advancedScan, bool reverse, bool partial,
                               bool relAddr, uint lba, uint requested, uint scanLength, out uint foundLba,
                               out uint foundBlocks, uint timeout, out double duration)
        {
            senseBuffer = new byte[64];
            byte[] cdb    = new byte[10];
            byte[] buffer = Array.Empty<byte>();
            foundLba    = 0;
            foundBlocks = 0;

            cdb[0] = (byte)ScsiCommands.MediumScan;

            if(written)
                cdb[1] += 0x10;

            if(advancedScan)
                cdb[1] += 0x08;

            if(reverse)
                cdb[1] += 0x04;

            if(partial)
                cdb[1] += 0x02;

            if(relAddr)
                cdb[1] += 0x01;

            cdb[2] = (byte)((lba & 0xFF000000) >> 24);
            cdb[3] = (byte)((lba & 0xFF0000)   >> 16);
            cdb[4] = (byte)((lba & 0xFF00)     >> 8);
            cdb[5] = (byte)(lba & 0xFF);

            if(requested  > 0 ||
               scanLength > 1)
            {
                buffer    = new byte[8];
                buffer[0] = (byte)((requested & 0xFF000000) >> 24);
                buffer[1] = (byte)((requested & 0xFF0000)   >> 16);
                buffer[2] = (byte)((requested & 0xFF00)     >> 8);
                buffer[3] = (byte)(requested & 0xFF);
                buffer[4] = (byte)((scanLength & 0xFF000000) >> 24);
                buffer[5] = (byte)((scanLength & 0xFF0000)   >> 16);
                buffer[6] = (byte)((scanLength & 0xFF00)     >> 8);
                buffer[7] = (byte)(scanLength & 0xFF);
                cdb[8]    = 8;
            }

            LastError = SendScsiCommand(cdb, ref buffer, out senseBuffer, timeout,
                                        buffer.Length == 0 ? ScsiDirection.None : ScsiDirection.Out, out duration,
                                        out bool sense);

            Error = LastError != 0;

            AaruConsole.DebugWriteLine("SCSI Device", "MEDIUM SCAN took {0} ms.", duration);

            if(Error)
                return sense;

            DecodedSense? decodedSense = Sense.Decode(senseBuffer);

            switch(decodedSense?.SenseKey)
            {
                case SenseKeys.NoSense: return false;
                case SenseKeys.Equal when decodedSense.Value.Fixed?.InformationValid == true:
                    foundBlocks = decodedSense.Value.Fixed.Value.CommandSpecific;
                    foundLba    = decodedSense.Value.Fixed.Value.Information;

                    return false;
                default: return sense;
            }
        }
    }
}