// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Checksum.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Core algorithms.
//
// --[ Description ] ----------------------------------------------------------
//
//     Multithreads checksumming and hashing.
//
// --[ 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 © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using System.Threading;
using DiscImageChef.Checksums;
using Schemas;

namespace DiscImageChef.Core
{
    [Flags]
    public enum EnableChecksum
    {
        Adler32    = 1,
        Crc16      = 2,
        Crc32      = 4,
        Crc64      = 8,
        Md5        = 16,
        Ripemd160  = 32,
        Sha1       = 64,
        Sha256     = 128,
        Sha384     = 256,
        Sha512     = 512,
        SpamSum    = 1024,
        Fletcher16 = 2048,
        Fletcher32 = 4096,
        All        = Adler32 | Crc16 | Crc32 | Crc64 | Md5 | Ripemd160 | Sha1 | Sha256 | Sha384 | Sha512 | SpamSum | Fletcher16 | Fletcher32
    }

    /// <summary>
    ///     Checksums and hashes data, with different algorithms multithreaded
    /// </summary>
    public class Checksum
    {
        IChecksum      adler32Ctx;
        HashPacket     adlerPkt;
        Thread         adlerThread;
        IChecksum      crc16Ctx;
        HashPacket     crc16Pkt;
        Thread         crc16Thread;
        IChecksum      crc32Ctx;
        HashPacket     crc32Pkt;
        Thread         crc32Thread;
        IChecksum      crc64Ctx;
        HashPacket     crc64Pkt;
        Thread         crc64Thread;
        EnableChecksum enabled;
        IChecksum      md5Ctx;
        HashPacket     md5Pkt;
        Thread         md5Thread;
        IChecksum      ripemd160Ctx;
        HashPacket     ripemd160Pkt;
        Thread         ripemd160Thread;
        IChecksum      sha1Ctx;
        HashPacket     sha1Pkt;
        Thread         sha1Thread;
        IChecksum      sha256Ctx;
        HashPacket     sha256Pkt;
        Thread         sha256Thread;
        IChecksum      sha384Ctx;
        HashPacket     sha384Pkt;
        Thread         sha384Thread;
        IChecksum      sha512Ctx;
        HashPacket     sha512Pkt;
        Thread         sha512Thread;
        HashPacket     spamsumPkt;
        Thread         spamsumThread;
        IChecksum      ssctx;
        HashPacket f16Pkt;
        Thread     f16Thread;
        IChecksum  f16Ctx;
        HashPacket f32Pkt;
        Thread     f32Thread;
        IChecksum  f32Ctx;

        public Checksum(EnableChecksum enabled = EnableChecksum.All)
        {
            this.enabled = enabled;

            if(enabled.HasFlag(EnableChecksum.Adler32))
            {
                adler32Ctx = new Adler32Context();
                adlerPkt   = new HashPacket {Context = adler32Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Crc16))
            {
                crc16Ctx = new Crc16Context();
                crc16Pkt = new HashPacket {Context = crc16Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Crc32))
            {
                crc32Ctx = new Crc32Context();
                crc32Pkt = new HashPacket {Context = crc32Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Crc64))
            {
                crc64Ctx = new Crc64Context();
                crc64Pkt = new HashPacket {Context = crc64Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Md5))
            {
                md5Ctx = new Md5Context();
                md5Pkt = new HashPacket {Context = md5Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Ripemd160))
            {
                ripemd160Ctx = new Ripemd160Context();
                ripemd160Pkt = new HashPacket {Context = ripemd160Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Sha1))
            {
                sha1Ctx = new Sha1Context();
                sha1Pkt = new HashPacket {Context = sha1Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Sha256))
            {
                sha256Ctx = new Sha256Context();
                sha256Pkt = new HashPacket {Context = sha256Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Sha384))
            {
                sha384Ctx = new Sha384Context();
                sha384Pkt = new HashPacket {Context = sha384Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Sha512))
            {
                sha512Ctx = new Sha512Context();
                sha512Pkt = new HashPacket {Context = sha512Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                ssctx      = new SpamSumContext();
                spamsumPkt = new HashPacket {Context = ssctx};
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher16))
            {
                f16Ctx = new Fletcher16Context();
                f16Pkt = new HashPacket {Context = f16Ctx};
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher32))
            {
                f32Ctx = new Fletcher32Context();
                f32Pkt = new HashPacket {Context = f32Ctx};
            }

            adlerThread     = new Thread(UpdateHash);
            crc16Thread     = new Thread(UpdateHash);
            crc32Thread     = new Thread(UpdateHash);
            crc64Thread     = new Thread(UpdateHash);
            md5Thread       = new Thread(UpdateHash);
            ripemd160Thread = new Thread(UpdateHash);
            sha1Thread      = new Thread(UpdateHash);
            sha256Thread    = new Thread(UpdateHash);
            sha384Thread    = new Thread(UpdateHash);
            sha512Thread    = new Thread(UpdateHash);
            spamsumThread   = new Thread(UpdateHash);
            f16Thread = new Thread(UpdateHash);
            f32Thread = new Thread(UpdateHash);
        }

        public void Update(byte[] data)
        {
            if(enabled.HasFlag(EnableChecksum.Adler32))
            {
                adlerPkt.Data = data;
                adlerThread.Start(adlerPkt);
            }

            if(enabled.HasFlag(EnableChecksum.Crc16))
            {
                crc16Pkt.Data = data;
                crc16Thread.Start(crc16Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Crc32))
            {
                crc32Pkt.Data = data;
                crc32Thread.Start(crc32Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Crc64))
            {
                crc64Pkt.Data = data;
                crc64Thread.Start(crc64Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Md5))
            {
                md5Pkt.Data = data;
                md5Thread.Start(md5Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Ripemd160))
            {
                ripemd160Pkt.Data = data;
                ripemd160Thread.Start(ripemd160Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Sha1))
            {
                sha1Pkt.Data = data;
                sha1Thread.Start(sha1Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Sha256))
            {
                sha256Pkt.Data = data;
                sha256Thread.Start(sha256Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Sha384))
            {
                sha384Pkt.Data = data;
                sha384Thread.Start(sha384Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Sha512))
            {
                sha512Pkt.Data = data;
                sha512Thread.Start(sha512Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                spamsumPkt.Data = data;
                spamsumThread.Start(spamsumPkt);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher16))
            {
                f16Pkt.Data = data;
                f16Thread.Start(f16Pkt);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher32))
            {
                f32Pkt.Data = data;
                f32Thread.Start(f32Pkt);
            }

            while(adlerThread.IsAlive  || crc16Thread.IsAlive     || crc32Thread.IsAlive || crc64Thread.IsAlive  ||
                  md5Thread.IsAlive    || ripemd160Thread.IsAlive || sha1Thread.IsAlive  || sha256Thread.IsAlive ||
                  sha384Thread.IsAlive || sha512Thread.IsAlive    || spamsumThread.IsAlive || f16Thread.IsAlive || f32Thread.IsAlive) { }

            if(enabled.HasFlag(EnableChecksum.SpamSum)) adlerThread     = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) crc16Thread     = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) crc32Thread     = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) crc64Thread     = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) md5Thread       = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) ripemd160Thread = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) sha1Thread      = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) sha256Thread    = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) sha384Thread    = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) sha512Thread    = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) spamsumThread   = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) f16Thread = new Thread(UpdateHash);
            if(enabled.HasFlag(EnableChecksum.SpamSum)) f32Thread = new Thread(UpdateHash);
        }

        public List<ChecksumType> End()
        {
            List<ChecksumType> chks = new List<ChecksumType>();

            ChecksumType chk;

            if(enabled.HasFlag(EnableChecksum.All))
            {
                chk = new ChecksumType {type = ChecksumTypeType.adler32, Value = adler32Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc16))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc16, Value = crc16Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc32))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc32, Value = crc32Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc64))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc64, Value = crc64Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Md5))
            {
                chk = new ChecksumType {type = ChecksumTypeType.md5, Value = md5Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Ripemd160))
            {
                chk = new ChecksumType {type = ChecksumTypeType.ripemd160, Value = ripemd160Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha1))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha1, Value = sha1Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha256))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha256, Value = sha256Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha384))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha384, Value = sha384Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha512))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha512, Value = sha512Ctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                chk = new ChecksumType {type = ChecksumTypeType.spamsum, Value = ssctx.End()};
                chks.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher16))
            {
                chk = new ChecksumType {type = ChecksumTypeType.fletcher16, Value = f16Ctx.End()};
                chks.Add(chk);
            }

            if(!enabled.HasFlag(EnableChecksum.Fletcher32)) return chks;

            chk = new ChecksumType {type = ChecksumTypeType.fletcher32, Value = f32Ctx.End()};
            chks.Add(chk);

            return chks;
        }

        internal static List<ChecksumType> GetChecksums(byte[] data, EnableChecksum enabled = EnableChecksum.All)
        {
            IChecksum adler32CtxData   = null;
            IChecksum crc16CtxData     = null;
            IChecksum crc32CtxData     = null;
            IChecksum crc64CtxData     = null;
            IChecksum md5CtxData       = null;
            IChecksum ripemd160CtxData = null;
            IChecksum sha1CtxData      = null;
            IChecksum sha256CtxData    = null;
            IChecksum sha384CtxData    = null;
            IChecksum sha512CtxData    = null;
            IChecksum ssctxData        = null;
            IChecksum f16CtxData = null;
            IChecksum f32CtxData = null;

            Thread adlerThreadData     = new Thread(UpdateHash);
            Thread crc16ThreadData     = new Thread(UpdateHash);
            Thread crc32ThreadData     = new Thread(UpdateHash);
            Thread crc64ThreadData     = new Thread(UpdateHash);
            Thread md5ThreadData       = new Thread(UpdateHash);
            Thread ripemd160ThreadData = new Thread(UpdateHash);
            Thread sha1ThreadData      = new Thread(UpdateHash);
            Thread sha256ThreadData    = new Thread(UpdateHash);
            Thread sha384ThreadData    = new Thread(UpdateHash);
            Thread sha512ThreadData    = new Thread(UpdateHash);
            Thread spamsumThreadData   = new Thread(UpdateHash);
            Thread f16ThreadData = new Thread(UpdateHash);
            Thread f32ThreadData = new Thread(UpdateHash);

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                adler32CtxData          = new Adler32Context();
                HashPacket adlerPktData = new HashPacket {Context = adler32CtxData, Data = data};
                adlerThreadData.Start(adlerPktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                crc16CtxData            = new Crc16Context();
                HashPacket crc16PktData = new HashPacket {Context = crc16CtxData, Data = data};
                crc16ThreadData.Start(crc16PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                crc32CtxData            = new Crc32Context();
                HashPacket crc32PktData = new HashPacket {Context = crc32CtxData, Data = data};
                crc32ThreadData.Start(crc32PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                crc64CtxData            = new Crc64Context();
                HashPacket crc64PktData = new HashPacket {Context = crc64CtxData, Data = data};
                crc64ThreadData.Start(crc64PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                md5CtxData            = new Md5Context();
                HashPacket md5PktData = new HashPacket {Context = md5CtxData, Data = data};
                md5ThreadData.Start(md5PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                ripemd160CtxData            = new Ripemd160Context();
                HashPacket ripemd160PktData = new HashPacket {Context = ripemd160CtxData, Data = data};
                ripemd160ThreadData.Start(ripemd160PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                sha1CtxData            = new Sha1Context();
                HashPacket sha1PktData = new HashPacket {Context = sha1CtxData, Data = data};
                sha1ThreadData.Start(sha1PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                sha256CtxData            = new Sha256Context();
                HashPacket sha256PktData = new HashPacket {Context = sha256CtxData, Data = data};
                sha256ThreadData.Start(sha256PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                sha384CtxData            = new Sha384Context();
                HashPacket sha384PktData = new HashPacket {Context = sha384CtxData, Data = data};
                sha384ThreadData.Start(sha384PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                sha512CtxData            = new Sha512Context();
                HashPacket sha512PktData = new HashPacket {Context = sha512CtxData, Data = data};
                sha512ThreadData.Start(sha512PktData);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                ssctxData                 = new SpamSumContext();
                HashPacket spamsumPktData = new HashPacket {Context = ssctxData, Data = data};
                spamsumThreadData.Start(spamsumPktData);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher16))
            {
                f16CtxData            = new Fletcher16Context();
                HashPacket f16PktData = new HashPacket {Context = f16CtxData, Data = data};
                f16ThreadData.Start(f16PktData);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher32))
            {
                f32CtxData            = new Fletcher32Context();
                HashPacket f32PktData = new HashPacket {Context = f32CtxData, Data = data};
                f32ThreadData.Start(f32PktData);
            }
            
            while(adlerThreadData.IsAlive  || crc16ThreadData.IsAlive  || crc32ThreadData.IsAlive     ||
                  crc64ThreadData.IsAlive  || md5ThreadData.IsAlive    || ripemd160ThreadData.IsAlive ||
                  sha1ThreadData.IsAlive   || sha256ThreadData.IsAlive || sha384ThreadData.IsAlive    ||
                  sha512ThreadData.IsAlive || spamsumThreadData.IsAlive || f16ThreadData.IsAlive || f32ThreadData.IsAlive) { }

            List<ChecksumType> dataChecksums = new List<ChecksumType>();
            ChecksumType       chk;

            if(enabled.HasFlag(EnableChecksum.Adler32))
            {
                chk = new ChecksumType {type = ChecksumTypeType.adler32, Value = adler32CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc16))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc16, Value = crc16CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc32))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc32, Value = crc32CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Crc64))
            {
                chk = new ChecksumType {type = ChecksumTypeType.crc64, Value = crc64CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Md5))
            {
                chk = new ChecksumType {type = ChecksumTypeType.md5, Value = md5CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Ripemd160))
            {
                chk = new ChecksumType {type = ChecksumTypeType.ripemd160, Value = ripemd160CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha1))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha1, Value = sha1CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha256))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha256, Value = sha256CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha384))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha384, Value = sha384CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Sha512))
            {
                chk = new ChecksumType {type = ChecksumTypeType.sha512, Value = sha512CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.SpamSum))
            {
                chk = new ChecksumType {type = ChecksumTypeType.spamsum, Value = ssctxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher16))
            {
                chk = new ChecksumType {type = ChecksumTypeType.fletcher16, Value = f16CtxData.End()};
                dataChecksums.Add(chk);
            }

            if(enabled.HasFlag(EnableChecksum.Fletcher32))
            {
                chk = new ChecksumType {type = ChecksumTypeType.fletcher32, Value = f32CtxData.End()};
                dataChecksums.Add(chk);
            }

            return dataChecksums;
        }

        #region Threading helpers
        struct HashPacket
        {
            public IChecksum Context;
            public byte[]    Data;
        }

        static void UpdateHash(object packet)
        {
            ((HashPacket)packet).Context.Update(((HashPacket)packet).Data);
        }
        #endregion Threading helpers
    }
}