// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : SCSI.cs
// Version        : 1.0
// Author(s)      : Natalia Portillo
//
// Component      : Component
//
// Revision       : $Revision$
// Last change by : $Author$
// Date           : $Date$
//
// --[ Description ] ----------------------------------------------------------
//
// Description
//
// --[ 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 (C) 2011-2015 Claunia.com
// ****************************************************************************/
// //$Id$
using System;
using System.Collections.Generic;
using DiscImageChef.Console;
using DiscImageChef.Core.Logging;
using DiscImageChef.Devices;

namespace DiscImageChef.Core.Devices.Scanning
{
    public static class SCSI
    {
        public static ScanResults Scan(string MHDDLogPath, string IBGLogPath, string devicePath, Device dev)
        {
            ScanResults results = new ScanResults();
            bool aborted;
            MHDDLog mhddLog;
            IBGLog ibgLog;
            byte[] cmdBuf;
            byte[] senseBuf;
            bool sense = false;
            double duration;
            results.blocks = 0;
            uint blockSize = 0;
            ushort currentProfile = 0x0001;

            if(dev.IsRemovable)
            {
                sense = dev.ScsiTestUnitReady(out senseBuf, dev.Timeout, out duration);
                if(sense)
                {
                    Decoders.SCSI.FixedSense? decSense = Decoders.SCSI.Sense.DecodeFixed(senseBuf);
                    if(decSense.HasValue)
                    {
                        if(decSense.Value.ASC == 0x3A)
                        {
                            int leftRetries = 5;
                            while(leftRetries > 0)
                            {
                                DicConsole.WriteLine("\rWaiting for drive to become ready");
                                System.Threading.Thread.Sleep(2000);
                                sense = dev.ScsiTestUnitReady(out senseBuf, dev.Timeout, out duration);
                                if(!sense)
                                    break;

                                leftRetries--;
                            }

                            if(sense)
                            {
                                DicConsole.ErrorWriteLine("Please insert media in drive");
                                return results;
                            }
                        }
                        else if(decSense.Value.ASC == 0x04 && decSense.Value.ASCQ == 0x01)
                        {
                            int leftRetries = 10;
                            while(leftRetries > 0)
                            {
                                DicConsole.WriteLine("\rWaiting for drive to become ready");
                                System.Threading.Thread.Sleep(2000);
                                sense = dev.ScsiTestUnitReady(out senseBuf, dev.Timeout, out duration);
                                if(!sense)
                                    break;

                                leftRetries--;
                            }

                            if(sense)
                            {
                                DicConsole.ErrorWriteLine("Error testing unit was ready:\n{0}", Decoders.SCSI.Sense.PrettifySense(senseBuf));
                                return results;
                            }
                        }
                        else
                        {
                            DicConsole.ErrorWriteLine("Error testing unit was ready:\n{0}", Decoders.SCSI.Sense.PrettifySense(senseBuf));
                            return results;
                        }
                    }
                    else
                    {
                        DicConsole.ErrorWriteLine("Unknown testing unit was ready.");
                        return results;
                    }
                }
            }

            Reader scsiReader = null;

            if(dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.DirectAccess ||
                dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.MultiMediaDevice ||
                dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.OCRWDevice ||
                dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.OpticalDevice ||
                dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.SimplifiedDevice ||
                dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.WriteOnceDevice)
            {
                scsiReader = new Reader(dev, dev.Timeout, null, false);
                results.blocks = scsiReader.GetDeviceBlocks();
                if(scsiReader.FindReadCommand())
                {
                    DicConsole.ErrorWriteLine("Unable to read medium.");
                    return results;
                }
                blockSize = scsiReader.LogicalBlockSize;

                if(results.blocks != 0 && blockSize != 0)
                {
                    results.blocks++;
#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
                    DicConsole.WriteLine("Media has {0} blocks of {1} bytes/each. (for a total of {2} bytes)",
                        results.blocks, blockSize, results.blocks * (ulong)blockSize);
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
                }
            }

            if(dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.SequentialAccess)
            {
                DicConsole.WriteLine("Scanning will never be supported on SCSI Streaming Devices.");
                DicConsole.WriteLine("It has no sense to do it, and it will put too much strain on the tape.");
                return results;
            }

            if(results.blocks == 0)
            {
                DicConsole.ErrorWriteLine("Unable to read medium or empty medium present...");
                return results;
            }

            bool compactDisc = true;
            Decoders.CD.FullTOC.CDFullTOC? toc = null;

            if(dev.SCSIType == Decoders.SCSI.PeripheralDeviceTypes.MultiMediaDevice)
            {
                sense = dev.GetConfiguration(out cmdBuf, out senseBuf, 0, MmcGetConfigurationRt.Current, dev.Timeout, out duration);
                if(!sense)
                {
                    Decoders.SCSI.MMC.Features.SeparatedFeatures ftr = Decoders.SCSI.MMC.Features.Separate(cmdBuf);

                    currentProfile = ftr.CurrentProfile;

                    switch(ftr.CurrentProfile)
                    {
                        case 0x0005:
                        case 0x0008:
                        case 0x0009:
                        case 0x000A:
                        case 0x0020:
                        case 0x0021:
                        case 0x0022:
                            break;
                        default:
                            compactDisc = false;
                            break;
                    }
                }

                if(compactDisc)
                {
                    currentProfile = 0x0008;
                    // We discarded all discs that falsify a TOC before requesting a real TOC
                    // No TOC, no CD (or an empty one)
                    bool tocSense = dev.ReadRawToc(out cmdBuf, out senseBuf, 1, dev.Timeout, out duration);
                    if(!tocSense)
                        toc = Decoders.CD.FullTOC.Decode(cmdBuf);
                }
            }
            else
                compactDisc = false;

            byte[] readBuffer;
            uint blocksToRead = 64;

            results.A = 0; // <3ms
            results.B = 0; // >=3ms, <10ms
            results.C = 0; // >=10ms, <50ms
            results.D = 0; // >=50ms, <150ms
            results.E = 0; // >=150ms, <500ms
            results.F = 0; // >=500ms
            results.errored = 0;
            DateTime start;
            DateTime end;
            results.processingTime = 0;
            results.totalTime = 0;
            double currentSpeed = 0;
            results.maxSpeed = double.MinValue;
            results.minSpeed = double.MaxValue;
            results.unreadableSectors = new List<ulong>();

            aborted = false;
            System.Console.CancelKeyPress += (sender, e) =>
            {
                e.Cancel = aborted = true;
            };

            bool readcd = false;

            if(compactDisc)
            {
                if(toc == null)
                {
                    DicConsole.ErrorWriteLine("Error trying to decode TOC...");
                    return results;
                }

                readcd = !dev.ReadCd(out readBuffer, out senseBuf, 0, 2352, 1, MmcSectorTypes.AllTypes, false, false, true, MmcHeaderCodes.AllHeaders,
                    true, true, MmcErrorField.None, MmcSubchannel.None, dev.Timeout, out duration);

                if(readcd)
                    DicConsole.WriteLine("Using MMC READ CD command.");

                start = DateTime.UtcNow;

                while(true)
                {
                    if(readcd)
                    {
                        sense = dev.ReadCd(out readBuffer, out senseBuf, 0, 2352, blocksToRead, MmcSectorTypes.AllTypes, false, false, true, MmcHeaderCodes.AllHeaders,
                            true, true, MmcErrorField.None, MmcSubchannel.None, dev.Timeout, out duration);
                        if(dev.Error)
                            blocksToRead /= 2;
                    }

                    if(!dev.Error || blocksToRead == 1)
                        break;
                }

                if(dev.Error)
                {
                    DicConsole.ErrorWriteLine("Device error {0} trying to guess ideal transfer length.", dev.LastError);
                    return results;
                }

                DicConsole.WriteLine("Reading {0} sectors at a time.", blocksToRead);

                mhddLog = new MHDDLog(MHDDLogPath, dev, results.blocks, blockSize, blocksToRead);
                ibgLog = new IBGLog(IBGLogPath, currentProfile);

                for(ulong i = 0; i < results.blocks; i += blocksToRead)
                {
                    if(aborted)
                        break;

                    double cmdDuration = 0;

                    if((results.blocks - i) < blocksToRead)
                        blocksToRead = (uint)(results.blocks - i);

#pragma warning disable RECS0018 // Comparison of floating point numbers with equality operator
                    if(currentSpeed > results.maxSpeed && currentSpeed != 0)
                        results.maxSpeed = currentSpeed;
                    if(currentSpeed < results.minSpeed && currentSpeed != 0)
                        results.minSpeed = currentSpeed;
#pragma warning restore RECS0018 // Comparison of floating point numbers with equality operator

                    DicConsole.Write("\rReading sector {0} of {1} ({2:F3} MiB/sec.)", i, results.blocks, currentSpeed);

                    if(readcd)
                    {
                        sense = dev.ReadCd(out readBuffer, out senseBuf, (uint)i, 2352, blocksToRead, MmcSectorTypes.AllTypes, false, false, true, MmcHeaderCodes.AllHeaders,
                            true, true, MmcErrorField.None, MmcSubchannel.None, dev.Timeout, out cmdDuration);
                        results.processingTime += cmdDuration;
                    }

                    if(!sense)
                    {
                        if(cmdDuration >= 500)
                        {
                            results.F += blocksToRead;
                        }
                        else if(cmdDuration >= 150)
                        {
                            results.E += blocksToRead;
                        }
                        else if(cmdDuration >= 50)
                        {
                            results.D += blocksToRead;
                        }
                        else if(cmdDuration >= 10)
                        {
                            results.C += blocksToRead;
                        }
                        else if(cmdDuration >= 3)
                        {
                            results.B += blocksToRead;
                        }
                        else
                        {
                            results.A += blocksToRead;
                        }

                        mhddLog.Write(i, cmdDuration);
                        ibgLog.Write(i, currentSpeed * 1024);
                    }
                    else
                    {
                        DicConsole.DebugWriteLine("Media-Scan", "READ CD error:\n{0}", Decoders.SCSI.Sense.PrettifySense(senseBuf));

                        Decoders.SCSI.FixedSense? senseDecoded = Decoders.SCSI.Sense.DecodeFixed(senseBuf);
                        if(senseDecoded.HasValue)
                        {
                            // TODO: This error happens when changing from track type afaik. Need to solve that more cleanly
                            // LOGICAL BLOCK ADDRESS OUT OF RANGE
                            if((senseDecoded.Value.ASC != 0x21 || senseDecoded.Value.ASCQ != 0x00) &&
                                // ILLEGAL MODE FOR THIS TRACK (requesting sectors as-is, this is a firmware misconception when audio sectors
                                // are in a track where subchannel indicates data)
                                (senseDecoded.Value.ASC != 0x64 || senseDecoded.Value.ASCQ != 0x00))
                            {
                                results.errored += blocksToRead;
                                for(ulong b = i; b < i + blocksToRead; b++)
                                    results.unreadableSectors.Add(b);
                                if(cmdDuration < 500)
                                    mhddLog.Write(i, 65535);
                                else
                                    mhddLog.Write(i, cmdDuration);

                                ibgLog.Write(i, 0);
                            }
                        }
                        else
                        {
                            results.errored += blocksToRead;
                            for(ulong b = i; b < i + blocksToRead; b++)
                                results.unreadableSectors.Add(b);
                            if(cmdDuration < 500)
                                mhddLog.Write(i, 65535);
                            else
                                mhddLog.Write(i, cmdDuration);

                            ibgLog.Write(i, 0);
                        }
                    }

#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
                    currentSpeed = ((double)blockSize * blocksToRead / (double)1048576) / (cmdDuration / (double)1000);
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
                    GC.Collect();
                }
                end = DateTime.UtcNow;
                DicConsole.WriteLine();
                mhddLog.Close();
#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
                ibgLog.Close(dev, results.blocks, blockSize, (end - start).TotalSeconds, currentSpeed * 1024, (((double)blockSize * (double)(results.blocks + 1)) / 1024) / (results.processingTime / 1000), devicePath);
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
            }
            else
            {
                start = DateTime.UtcNow;

                DicConsole.WriteLine("Reading {0} sectors at a time.", blocksToRead);

                mhddLog = new MHDDLog(MHDDLogPath, dev, results.blocks, blockSize, blocksToRead);
                ibgLog = new IBGLog(IBGLogPath, currentProfile);

                for(ulong i = 0; i < results.blocks; i += blocksToRead)
                {
                    if(aborted)
                        break;

                    double cmdDuration = 0;

                    if((results.blocks - i) < blocksToRead)
                        blocksToRead = (uint)(results.blocks - i);

#pragma warning disable RECS0018 // Comparison of floating point numbers with equality operator
                    if(currentSpeed > results.maxSpeed && currentSpeed != 0)
                        results.maxSpeed = currentSpeed;
                    if(currentSpeed < results.minSpeed && currentSpeed != 0)
                        results.minSpeed = currentSpeed;
#pragma warning restore RECS0018 // Comparison of floating point numbers with equality operator

                    DicConsole.Write("\rReading sector {0} of {1} ({2:F3} MiB/sec.)", i, results.blocks, currentSpeed);

                    sense = scsiReader.ReadBlocks(out readBuffer, i, blocksToRead, out cmdDuration);
                    results.processingTime += cmdDuration;

                    if(!sense && !dev.Error)
                    {
                        if(cmdDuration >= 500)
                            results.F += blocksToRead;
                        else if(cmdDuration >= 150)
                            results.E += blocksToRead;
                        else if(cmdDuration >= 50)
                            results.D += blocksToRead;
                        else if(cmdDuration >= 10)
                            results.C += blocksToRead;
                        else if(cmdDuration >= 3)
                            results.B += blocksToRead;
                        else
                            results.A += blocksToRead;

                        mhddLog.Write(i, cmdDuration);
                        ibgLog.Write(i, currentSpeed * 1024);
                    }
                    // TODO: Separate errors on kind of errors.
                    else
                    {
                        results.errored += blocksToRead;
                        for(ulong b = i; b < i + blocksToRead; b++)
                            results.unreadableSectors.Add(b);
                        if(cmdDuration < 500)
                            mhddLog.Write(i, 65535);
                        else
                            mhddLog.Write(i, cmdDuration);
                        ibgLog.Write(i, 0);
                    }

#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
                    currentSpeed = ((double)blockSize * blocksToRead / (double)1048576) / (cmdDuration / (double)1000);
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
                }

                end = DateTime.UtcNow;
                DicConsole.WriteLine();
                mhddLog.Close();
#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
                ibgLog.Close(dev, results.blocks, blockSize, (end - start).TotalSeconds, currentSpeed * 1024, (((double)blockSize * (double)(results.blocks + 1)) / 1024) / (results.processingTime / 1000), devicePath);
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
            }

            results.seekMax = double.MinValue;
            results.seekMin = double.MaxValue;
            results.seekTotal = 0;
            const int seekTimes = 1000;

            double seekCur = 0;

            Random rnd = new Random();

            uint seekPos = (uint)rnd.Next((int)results.blocks);

            for(int i = 0; i < seekTimes; i++)
            {
                if(aborted)
                    break;

                seekPos = (uint)rnd.Next((int)results.blocks);

                DicConsole.Write("\rSeeking to sector {0}...\t\t", seekPos);

                if(scsiReader.CanSeek)
                    scsiReader.Seek(seekPos, out seekCur);
                else
                    scsiReader.ReadBlock(out readBuffer, seekPos, out seekCur);

#pragma warning disable RECS0018 // Comparison of floating point numbers with equality operator
                if(seekCur > results.seekMax && seekCur != 0)
                    results.seekMax = seekCur;
                if(seekCur < results.seekMin && seekCur != 0)
                    results.seekMin = seekCur;
#pragma warning restore RECS0018 // Comparison of floating point numbers with equality operator

                results.seekTotal += seekCur;
                GC.Collect();
            }

            DicConsole.WriteLine();

            results.processingTime /= 1000;
            results.totalTime = (end - start).TotalSeconds;
#pragma warning disable IDE0004 // Without this specific cast, it gives incorrect values
            results.avgSpeed = (((double)blockSize * (double)(results.blocks + 1)) / 1048576) / results.processingTime;
#pragma warning restore IDE0004 // Without this specific cast, it gives incorrect values
            results.seekTimes = seekTimes;

            return results;
        }
    }
}
