// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Read.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
//     Reads Apple New Disk Image Format.
//
// --[ 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 © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Claunia.Encoding;
using Claunia.RsrcFork;
using DiscImageChef.CommonTypes;
using DiscImageChef.CommonTypes.Enums;
using DiscImageChef.CommonTypes.Exceptions;
using DiscImageChef.CommonTypes.Interfaces;
using DiscImageChef.Compression;
using DiscImageChef.Console;
using SharpCompress.Compressors.ADC;
using Version = Resources.Version;

namespace DiscImageChef.DiscImages
{
    public partial class Ndif
    {
        public bool Open(IFilter imageFilter)
        {
            if(!imageFilter.HasResourceFork() || imageFilter.GetResourceForkLength() == 0) return false;

            ResourceFork rsrcFork;
            Resource     rsrc;
            short[]      bcems;

            try
            {
                rsrcFork = new ResourceFork(imageFilter.GetResourceForkStream());
                if(!rsrcFork.ContainsKey(NDIF_RESOURCE)) return false;

                rsrc = rsrcFork.GetResource(NDIF_RESOURCE);

                bcems = rsrc.GetIds();

                if(bcems == null || bcems.Length == 0) return false;
            }
            catch(InvalidCastException) { return false; }

            imageInfo.Sectors = 0;
            foreach(byte[] bcem in bcems.Select(id => rsrc.GetResource(NDIF_RESOURCEID)))
            {
                if(bcem.Length < 128) return false;

                header = BigEndianMarshal.ByteArrayToStructureBigEndian<ChunkHeader>(bcem);

                DicConsole.DebugWriteLine("NDIF plugin", "footer.type = {0}",   header.version);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.driver = {0}", header.driver);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.name = {0}",
                                          StringHandlers.PascalToString(header.name,
                                                                        Encoding.GetEncoding("macintosh")));
                DicConsole.DebugWriteLine("NDIF plugin", "footer.sectors = {0}",            header.sectors);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.maxSectorsPerChunk = {0}", header.maxSectorsPerChunk);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.dataOffset = {0}",         header.dataOffset);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.crc = 0x{0:X7}",           header.crc);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.segmented = {0}",          header.segmented);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.p1 = 0x{0:X8}",            header.p1);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.p2 = 0x{0:X8}",            header.p2);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.unknown[0] = 0x{0:X8}",    header.unknown[0]);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.unknown[1] = 0x{0:X8}",    header.unknown[1]);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.unknown[2] = 0x{0:X8}",    header.unknown[2]);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.unknown[3] = 0x{0:X8}",    header.unknown[3]);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.unknown[4] = 0x{0:X8}",    header.unknown[4]);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.encrypted = {0}",          header.encrypted);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.hash = 0x{0:X8}",          header.hash);
                DicConsole.DebugWriteLine("NDIF plugin", "footer.chunks = {0}",             header.chunks);

                // Block chunks and headers
                chunks = new Dictionary<ulong, BlockChunk>();

                BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian;

                for(int i = 0; i < header.chunks; i++)
                {
                    // Obsolete read-only NDIF only prepended the header and then put the image without any kind of block references.
                    // So let's falsify a block chunk
                    BlockChunk bChnk  = new BlockChunk();
                    byte[]     sector = new byte[4];
                    Array.Copy(bcem, 128 + 0 + i * 12, sector, 1, 3);
                    bChnk.sector = BigEndianBitConverter.ToUInt32(sector, 0);
                    bChnk.type   = bcem[128 + 3                                 + i * 12];
                    bChnk.offset = BigEndianBitConverter.ToUInt32(bcem, 128 + 4 + i * 12);
                    bChnk.length = BigEndianBitConverter.ToUInt32(bcem, 128 + 8 + i * 12);

                    DicConsole.DebugWriteLine("NDIF plugin", "bHdr.chunk[{0}].type = 0x{1:X2}", i, bChnk.type);
                    DicConsole.DebugWriteLine("NDIF plugin", "bHdr.chunk[{0}].sector = {1}",    i, bChnk.sector);
                    DicConsole.DebugWriteLine("NDIF plugin", "bHdr.chunk[{0}].offset = {1}",    i, bChnk.offset);
                    DicConsole.DebugWriteLine("NDIF plugin", "bHdr.chunk[{0}].length = {1}",    i, bChnk.length);

                    if(bChnk.type == CHUNK_TYPE_END) break;

                    bChnk.offset += header.dataOffset;
                    bChnk.sector += (uint)imageInfo.Sectors;

                    // TODO: Handle compressed chunks
                    switch(bChnk.type)
                    {
                        case CHUNK_TYPE_KENCODE:
                            throw new
                                ImageNotSupportedException("Chunks compressed with KenCode are not yet supported.");
                        case CHUNK_TYPE_LZH:
                            throw new ImageNotSupportedException("Chunks compressed with LZH are not yet supported.");
                        case CHUNK_TYPE_STUFFIT:
                            throw new
                                ImageNotSupportedException("Chunks compressed with StuffIt! are not yet supported.");
                    }

                    // TODO: Handle compressed chunks
                    if(bChnk.type > CHUNK_TYPE_COPY    && bChnk.type < CHUNK_TYPE_KENCODE ||
                       bChnk.type > CHUNK_TYPE_ADC     && bChnk.type < CHUNK_TYPE_STUFFIT ||
                       bChnk.type > CHUNK_TYPE_STUFFIT && bChnk.type < CHUNK_TYPE_END     || bChnk.type == 1)
                        throw new ImageNotSupportedException($"Unsupported chunk type 0x{bChnk.type:X8} found");

                    chunks.Add(bChnk.sector, bChnk);
                }

                imageInfo.Sectors += header.sectors;
            }

            if(header.segmented > 0) throw new ImageNotSupportedException("Segmented images are not yet supported.");

            if(header.encrypted > 0) throw new ImageNotSupportedException("Encrypted images are not yet supported.");

            switch(imageInfo.Sectors)
            {
                case 1440:
                    imageInfo.MediaType = MediaType.DOS_35_DS_DD_9;
                    break;
                case 1600:
                    imageInfo.MediaType = MediaType.AppleSonyDS;
                    break;
                case 2880:
                    imageInfo.MediaType = MediaType.DOS_35_HD;
                    break;
                case 3360:
                    imageInfo.MediaType = MediaType.DMF;
                    break;
                default:
                    imageInfo.MediaType = MediaType.GENERIC_HDD;
                    break;
            }

            if(rsrcFork.ContainsKey(0x76657273))
            {
                Resource versRsrc = rsrcFork.GetResource(0x76657273);
                if(versRsrc != null)
                {
                    byte[] vers = versRsrc.GetResource(versRsrc.GetIds()[0]);

                    Version version = new Version(vers);

                    string release = null;
                    string dev     = null;
                    string pre     = null;

                    string major                              = $"{version.MajorVersion}";
                    string minor                              = $".{version.MinorVersion / 10}";
                    if(version.MinorVersion % 10 > 0) release = $".{version.MinorVersion % 10}";
                    switch(version.DevStage)
                    {
                        case Version.DevelopmentStage.Alpha:
                            dev = "a";
                            break;
                        case Version.DevelopmentStage.Beta:
                            dev = "b";
                            break;
                        case Version.DevelopmentStage.PreAlpha:
                            dev = "d";
                            break;
                    }

                    if(dev == null && version.PreReleaseVersion > 0) dev = "f";

                    if(dev != null) pre = $"{version.PreReleaseVersion}";

                    imageInfo.ApplicationVersion = $"{major}{minor}{release}{dev}{pre}";
                    imageInfo.Application        = version.VersionString;
                    imageInfo.Comments           = version.VersionMessage;

                    if(version.MajorVersion      == 3) imageInfo.Application = "ShrinkWrap™";
                    else if(version.MajorVersion == 6) imageInfo.Application = "DiskCopy";
                }
            }

            DicConsole.DebugWriteLine("NDIF plugin", "Image application = {0} version {1}", imageInfo.Application,
                                      imageInfo.ApplicationVersion);

            sectorCache           = new Dictionary<ulong, byte[]>();
            chunkCache            = new Dictionary<ulong, byte[]>();
            currentChunkCacheSize = 0;
            imageStream           = imageFilter.GetDataForkStream();
            buffersize            = header.maxSectorsPerChunk * SECTOR_SIZE;

            imageInfo.CreationTime         = imageFilter.GetCreationTime();
            imageInfo.LastModificationTime = imageFilter.GetLastWriteTime();
            imageInfo.MediaTitle =
                StringHandlers.PascalToString(header.name, Encoding.GetEncoding("macintosh"));
            imageInfo.SectorSize         = SECTOR_SIZE;
            imageInfo.XmlMediaType       = XmlMediaType.BlockMedia;
            imageInfo.ImageSize          = imageInfo.Sectors * SECTOR_SIZE;
            imageInfo.ApplicationVersion = "6";
            imageInfo.Application        = "Apple DiskCopy";

            switch(imageInfo.MediaType)
            {
                case MediaType.AppleSonyDS:
                    imageInfo.Cylinders       = 80;
                    imageInfo.Heads           = 2;
                    imageInfo.SectorsPerTrack = 10;
                    break;
                case MediaType.DOS_35_DS_DD_9:
                    imageInfo.Cylinders       = 80;
                    imageInfo.Heads           = 2;
                    imageInfo.SectorsPerTrack = 9;
                    break;
                case MediaType.DOS_35_HD:
                    imageInfo.Cylinders       = 80;
                    imageInfo.Heads           = 2;
                    imageInfo.SectorsPerTrack = 18;
                    break;
                case MediaType.DMF:
                    imageInfo.Cylinders       = 80;
                    imageInfo.Heads           = 2;
                    imageInfo.SectorsPerTrack = 21;
                    break;
                default:
                    imageInfo.MediaType       = MediaType.GENERIC_HDD;
                    imageInfo.Cylinders       = (uint)(imageInfo.Sectors / 16 / 63);
                    imageInfo.Heads           = 16;
                    imageInfo.SectorsPerTrack = 63;
                    break;
            }

            return true;
        }

        public byte[] ReadSector(ulong sectorAddress)
        {
            if(sectorAddress > imageInfo.Sectors - 1)
                throw new ArgumentOutOfRangeException(nameof(sectorAddress),
                                                      $"Sector address {sectorAddress} not found");

            if(sectorCache.TryGetValue(sectorAddress, out byte[] sector)) return sector;

            BlockChunk currentChunk     = new BlockChunk();
            bool       chunkFound       = false;
            ulong      chunkStartSector = 0;

            foreach(KeyValuePair<ulong, BlockChunk> kvp in chunks.Where(kvp => sectorAddress >= kvp.Key))
            {
                currentChunk     = kvp.Value;
                chunkFound       = true;
                chunkStartSector = kvp.Key;
            }

            long relOff = ((long)sectorAddress - (long)chunkStartSector) * SECTOR_SIZE;

            if(relOff < 0)
                throw new ArgumentOutOfRangeException(nameof(relOff),
                                                      $"Got a negative offset for sector {sectorAddress}. This should not happen.");

            if(!chunkFound)
                throw new ArgumentOutOfRangeException(nameof(sectorAddress),
                                                      $"Sector address {sectorAddress} not found");

            if((currentChunk.type & CHUNK_TYPE_COMPRESSED_MASK) == CHUNK_TYPE_COMPRESSED_MASK)
            {
                if(!chunkCache.TryGetValue(chunkStartSector, out byte[] buffer))
                {
                    byte[] cmpBuffer = new byte[currentChunk.length];
                    imageStream.Seek(currentChunk.offset, SeekOrigin.Begin);
                    imageStream.Read(cmpBuffer, 0, cmpBuffer.Length);
                    MemoryStream cmpMs = new MemoryStream(cmpBuffer);
                    int          realSize;

                    switch(currentChunk.type)
                    {
                        case CHUNK_TYPE_ADC:
                        {
                            Stream decStream = new ADCStream(cmpMs);
                            byte[] tmpBuffer = new byte[buffersize];
                            realSize = decStream.Read(tmpBuffer, 0, (int)buffersize);
                            buffer   = new byte[realSize];
                            Array.Copy(tmpBuffer, 0, buffer, 0, realSize);
                            break;
                        }
                        case CHUNK_TYPE_RLE:
                        {
                            byte[] tmpBuffer = new byte[buffersize];
                            realSize = 0;
                            AppleRle rle = new AppleRle(cmpMs);
                            for(int i = 0; i < buffersize; i++)
                            {
                                int b = rle.ProduceByte();
                                if(b == -1) break;

                                tmpBuffer[i] = (byte)b;
                                realSize++;
                            }

                            buffer = new byte[realSize];
                            Array.Copy(tmpBuffer, 0, buffer, 0, realSize);
                            break;
                        }
                        default:
                            throw new
                                ImageNotSupportedException($"Unsupported chunk type 0x{currentChunk.type:X8} found");
                    }

                    if(currentChunkCacheSize + realSize > MAX_CACHE_SIZE)
                    {
                        chunkCache.Clear();
                        currentChunkCacheSize = 0;
                    }

                    chunkCache.Add(chunkStartSector, buffer);
                    currentChunkCacheSize += (uint)realSize;
                }

                sector = new byte[SECTOR_SIZE];
                Array.Copy(buffer, relOff, sector, 0, SECTOR_SIZE);

                if(sectorCache.Count >= MAX_CACHED_SECTORS) sectorCache.Clear();

                sectorCache.Add(sectorAddress, sector);

                return sector;
            }

            switch(currentChunk.type)
            {
                case CHUNK_TYPE_NOCOPY:
                    sector = new byte[SECTOR_SIZE];

                    if(sectorCache.Count >= MAX_CACHED_SECTORS) sectorCache.Clear();

                    sectorCache.Add(sectorAddress, sector);
                    return sector;
                case CHUNK_TYPE_COPY:
                    imageStream.Seek(currentChunk.offset + relOff, SeekOrigin.Begin);
                    sector = new byte[SECTOR_SIZE];
                    imageStream.Read(sector, 0, sector.Length);

                    if(sectorCache.Count >= MAX_CACHED_SECTORS) sectorCache.Clear();

                    sectorCache.Add(sectorAddress, sector);
                    return sector;
            }

            throw new ImageNotSupportedException($"Unsupported chunk type 0x{currentChunk.type:X8} found");
        }

        public byte[] ReadSectors(ulong sectorAddress, uint length)
        {
            if(sectorAddress > imageInfo.Sectors - 1)
                throw new ArgumentOutOfRangeException(nameof(sectorAddress),
                                                      $"Sector address {sectorAddress} not found");

            if(sectorAddress + length > imageInfo.Sectors)
                throw new ArgumentOutOfRangeException(nameof(length), "Requested more sectors than available");

            MemoryStream ms = new MemoryStream();

            for(uint i = 0; i < length; i++)
            {
                byte[] sector = ReadSector(sectorAddress + i);
                ms.Write(sector, 0, sector.Length);
            }

            return ms.ToArray();
        }
    }
}