BizHawk/BizHawk.Emulation.DiscSystem/Disc.cs

using System;
using System.Linq;
using System.Text;
using System.IO;
using System.Collections.Generic;

//http://www.pctechguide.com/iso-9660-data-format-for-cds-cd-roms-cd-rs-and-cd-rws
//http://linux.die.net/man/1/cue2toc

//http://cdemu.sourceforge.net/project.php#sf

//apparently cdrdao is the ultimate linux tool for doing this stuff but it doesnt support DAO96 (or other DAO modes) that would be necessary to extract P-Q subchannels
//(cdrdao only supports R-W)

//here is a featureset list of windows cd burning programs (useful for cuesheet compatibility info)
//http://www.dcsoft.com/cue_mastering_progs.htm

//good
//http://linux-sxs.org/bedtime/cdapi.html
//http://en.wikipedia.org/wiki/Track_%28CD%29
//http://docs.google.com/viewer?a=v&q=cache:imNKye05zIEJ:www.13thmonkey.org/documentation/SCSI/mmc-r10a.pdf+q+subchannel+TOC+format&hl=en&gl=us&pid=bl&srcid=ADGEEShtYqlluBX2lgxTL3pVsXwk6lKMIqSmyuUCX4RJ3DntaNq5vI2pCvtkyze-fumj7vvrmap6g1kOg5uAVC0IxwU_MRhC5FB0c_PQ2BlZQXDD7P3GeNaAjDeomelKaIODrhwOoFNb&sig=AHIEtbRXljAcFjeBn3rMb6tauHWjSNMYrw
//r:\consoles\~docs\yellowbook
//http://digitalx.org/cue-sheet/examples/
//

//"qemu cdrom emulator"
//http://www.koders.com/c/fid7171440DEC7C18B932715D671DEE03743111A95A.aspx
 
//less good
//http://www.cyberciti.biz/faq/getting-volume-information-from-cds-iso-images/
//http://www.cims.nyu.edu/cgi-systems/man.cgi?section=7I&topic=cdio

//ideas:
/*
 * do some stuff asynchronously. for example, decoding mp3 sectors.
 * keep a list of 'blobs' (giant bins or decoded wavs likely) which can reference the disk
 * keep a list of sectors and the blob/offset from which they pull -- also whether the sector is available
 * if it is not available and something requests it then it will have to block while that sector gets generated
 * perhaps the blobs know how to resolve themselves and the requested sector can be immediately resolved (priority boost)
 * mp3 blobs should be hashed and dropped in %TEMP% as a wav decode
*/

//here is an MIT licensed C mp3 decoder
//http://core.fluendo.com/gstreamer/src/gst-fluendo-mp3/

/*information on saturn TOC and session data structures is on pdf page 58 of System Library User's Manual;
 * as seen in yabause, there are 1000 u32s in this format:
 * Ctrl[4bit] Adr[4bit] StartFrameAddressFAD[24bit] (nonexisting tracks are 0xFFFFFFFF)
 * Followed by Fist Track Information, Last Track Information..
 * Ctrl[4bit] Adr[4bit] FirstTrackNumber/LastTrackNumber[8bit] and then some stuff I dont understand
 * ..and Read Out Information:
 * Ctrl[4bit] Adr[4bit] ReadOutStartFrameAddress[24bit]
 * 
 * Also there is some stuff about FAD of sessions.
 * This should be generated by the saturn core, but we need to make sure we pass down enough information to do it
*/

//2048 bytes packed into 2352: 
//12 bytes sync(00 ff ff ff ff ff ff ff ff ff ff 00)
//3 bytes sector address (min+A0),sec,frac //does this correspond to ccd `point` field in the TOC entries?
//sector mode byte (0: silence; 1: 2048Byte mode (EDC,ECC,CIRC), 2: mode2 (could be 2336[vanilla mode2], 2048[xa mode2 form1], 2324[xa mode2 form2])
//cue sheets may use mode1_2048 (and the error coding needs to be regenerated to get accurate raw data) or mode1_2352 (the entire sector is present)
//audio is a different mode, seems to be just 2352 bytes with no sync, header or error correction. i guess the CIRC error correction is still there

namespace BizHawk.Emulation.DiscSystem
{
	public partial class Disc : IDisposable
	{
		public interface ISector
		{
			/// <summary>
			/// reads the entire sector, raw
			/// </summary>
			int Read_2352(byte[] buffer, int offset);

			/// <summary>
			/// reads 2048 bytes of userdata.. precisely what this means isnt always 100% certain (for instance mode2 form 0 has 2336 bytes of userdata instead of 2048)..
			/// ..but its certain enough for this to be useful
			/// </summary>
			int Read_2048(byte[] buffer, int offset);
		}

		/// <summary>
		/// Presently, an IBlob doesn't need to work multithreadedly. It's quite an onerous demand.
		/// This should probably be managed by the Disc class somehow, or by the user making another Disc.
		/// </summary>
		public interface IBlob : IDisposable
		{
			/// <summary>
			/// what a weird parameter order. normally the dest buffer would be first. weird.
			/// </summary>
			/// <param name="byte_pos">location in the blob to read from</param>
			/// <param name="buffer">destination buffer for read data</param>
			/// <param name="offset">offset into destination buffer</param>
			/// <param name="count">amount to read</param>
			int Read(long byte_pos, byte[] buffer, int offset, int count);
		}

		public sealed class Blob_ZeroPadAdapter : IBlob
		{
			public Blob_ZeroPadAdapter(IBlob baseBlob, long padFrom, long padLen)
			{
				this.baseBlob = baseBlob;
				this.padFrom = padFrom;
				this.padLen = padLen;
			}

			public int Read(long byte_pos, byte[] buffer, int offset, int count)
			{
				throw new NotImplementedException("Blob_ZeroPadAdapter hasnt been tested yet! please report this!");

				//something about this seems unnecessarily complex, but... i dunno.
				/*
				//figure out how much remains until the zero-padding begins
				long remain = byte_pos - padFrom;
				int todo;
				if (remain < count)
					todo = (int)remain;
				else todo = count;

				//read up until the zero-padding
				int totalRead = 0;
				int readed = baseBlob.Read(byte_pos, buffer, offset, todo);
				totalRead += readed;
				offset += todo;

				//if we didnt read enough, we certainly shouldnt try to read any more
				if (readed < todo)
					return readed;

				//if that was all we needed, then we're done
				count -= todo;
				if (count == 0)
					return totalRead;

				//if we need more, it must come from zero-padding
				remain = padLen;
				if (remain < count)
					todo = (int)remain;
				else todo = count;

				Array.Clear(buffer, offset, todo);
				totalRead += todo;

				return totalRead;
				*/
			}

			public void Dispose()
			{
				baseBlob.Dispose();
			}

			private readonly IBlob baseBlob;
			private long padFrom;
			private long padLen;
		}

		private class Blob_RawFile : IBlob
		{
			public string PhysicalPath { 
				get
				{
					return physicalPath;
				}
				set
				{
					physicalPath = value;
					length = new FileInfo(physicalPath).Length;
				}
			}
			string physicalPath;
			long length;

			public long Offset = 0;

			BufferedStream fs;
			public void Dispose()
			{
				if (fs != null)
				{
					fs.Dispose();
					fs = null;
				}
			}
			public int Read(long byte_pos, byte[] buffer, int offset, int count)
			{
				//use quite a large buffer, because normally we will be reading these sequentially but in small chunks.
				//this enhances performance considerably
				const int buffersize = 2352 * 75 * 2;
				if (fs == null)
					fs = new BufferedStream(new FileStream(physicalPath, FileMode.Open, FileAccess.Read, FileShare.Read), buffersize);
				long target = byte_pos + Offset;
				if(fs.Position != target)
					fs.Position = target;
				return fs.Read(buffer, offset, count);
			}
			public long Length
			{
				get
				{
					return length;
				}
			}
		}

		/// <summary>
		/// this ISector is dumb and only knows how to drag chunks off a source blob
		/// </summary>
		class Sector_RawBlob : ISector
		{
			public IBlob Blob;
			public long Offset;
			public int Read_2352(byte[] buffer, int offset)
			{
				return Blob.Read(Offset, buffer, offset, 2352);
			}
			public int Read_2048(byte[] buffer, int offset)
			{
				return Blob.Read(Offset, buffer, offset, 2048);
			}
		}

		/// <summary>
		/// this ISector always returns zeroes
		/// </summary>
		class Sector_Zero : ISector
		{
			public int Read_2352(byte[] buffer, int offset)
			{
				Array.Clear(buffer, 0, 2352);
				return 2352;
			}
			public int Read_2048(byte[] buffer, int offset)
			{
				Array.Clear(buffer, 0, 2048);
				return 2048;
			}
		}


		// ------ replaced by Blob_ZeroPadAdapter
		///// <summary>
		///// this ISector adapts another ISector by always returning zeroes 
		///// TODO I dont like the way this works. I think blobs should get adapted instead to zero-pad to a certain length.
		///// </summary>
		//class Sector_ZeroPad : ISector
		//{
		//  public ISector BaseSector;
		//  public int BaseLength;
		//  public int Read(byte[] buffer, int offset)
		//  {
		//    return _Read(buffer, offset, 2352);
		//  }
		//  public int Read_2048(byte[] buffer, int offset)
		//  {
		//    return _Read(buffer, offset, 2352);
		//  }
		//  int _Read(byte[] buffer, int offset, int amount)
		//  {
		//    int read = BaseSector.Read(buffer, offset);
		//    if(read < BaseLength) return read;
		//    for (int i = BaseLength; i < amount; i++)
		//      buffer[offset + i] = 0;
		//    return amount;
		//  }
		//}

		abstract class Sector_Mode1_or_Mode2_2352 : ISector
		{
			public ISector BaseSector;
			public abstract int Read_2352(byte[] buffer, int offset);
			public abstract int Read_2048(byte[] buffer, int offset);
		}

		/// <summary>
		/// This ISector is a raw MODE1 sector
		/// </summary>
		class Sector_Mode1_2352 : Sector_Mode1_or_Mode2_2352
		{
			public override int Read_2352(byte[] buffer, int offset)
			{
				return BaseSector.Read_2352(buffer, offset);
			}
			public override int Read_2048(byte[] buffer, int offset)
			{
				//to get 2048 bytes out of this sector type, start 16 bytes in
				int ret = BaseSector.Read_2352(TempSector, 0);
				Buffer.BlockCopy(TempSector, 16, buffer, offset, 2048);
				System.Diagnostics.Debug.Assert(buffer != TempSector);
				return 2048;
			}

			[ThreadStatic]
			static byte[] TempSector = new byte[2352];
		}

		/// <summary>
		/// this ISector is a raw MODE2 sector. could be form 0,1,2... who can say? supposedly:
		/// To tell the different Mode 2s apart you have to examine bytes 16-23 of the sector (the first 8 bytes of Mode Data). 
		/// If bytes 16-19 are not the same as 20-23, then it is Mode 2. If they are equal and bit 5 is on (0x20), then it is Mode 2 Form 2. Otherwise it is Mode 2 Form 1.
		/// ...but we're not using this information in any way
		/// </summary>
		class Sector_Mode2_2352 : Sector_Mode1_or_Mode2_2352
		{
			public override int Read_2352(byte[] buffer, int offset)
			{
				return BaseSector.Read_2352(buffer, offset);
			}

			public override int Read_2048(byte[] buffer, int offset)
			{
				//to get 2048 bytes out of this sector type, start 24 bytes in
				int ret = BaseSector.Read_2352(TempSector, 0);
				Buffer.BlockCopy(TempSector, 24, buffer, offset, 2048);
				System.Diagnostics.Debug.Assert(buffer != TempSector);
				return 2048;
			}

			[ThreadStatic]
			static byte[] TempSector = new byte[2352];
		}

		private static byte BCD_Byte(byte val)
		{
			byte ret = (byte)(val % 10);
			ret += (byte)(16 * (val / 10));
			return ret;
		}

		//a blob that also has an ECM cache associated with it. maybe one day.
		class ECMCacheBlob
		{
			public ECMCacheBlob(IBlob blob)
			{
				BaseBlob = blob;
			}
			public IBlob BaseBlob;
		}

		/// <summary>
		/// this ISector is a MODE1 sector that is generating itself from an underlying MODE1/2048 userdata piece
		/// </summary>
		class Sector_Mode1_2048 : ISector
		{
			public Sector_Mode1_2048(int ABA)
			{
				byte aba_min = (byte)(ABA / 60 / 75);
				byte aba_sec = (byte)((ABA / 75) % 60);
				byte aba_frac = (byte)(ABA % 75);
				bcd_aba_min = BCD_Byte(aba_min);
				bcd_aba_sec = BCD_Byte(aba_sec);
				bcd_aba_frac = BCD_Byte(aba_frac);
			}
			byte bcd_aba_min, bcd_aba_sec, bcd_aba_frac;

			public ECMCacheBlob Blob;
			public long Offset;
			byte[] extra_data;
			bool has_extra_data;

			public int Read_2048(byte[] buffer, int offset)
			{
				//this is easy. we only have 2048 bytes, and 2048 bytes were requested
				return Blob.BaseBlob.Read(Offset, buffer, offset, 2048);
			}

			public int Read_2352(byte[] buffer, int offset)
			{
				//user data
				int read = Blob.BaseBlob.Read(Offset, buffer, offset + 16, 2048);

				//if we read the 2048 physical bytes OK, then return the complete sector
				if (read == 2048 && has_extra_data)
				{
					Buffer.BlockCopy(extra_data, 0, buffer, offset, 16);
					Buffer.BlockCopy(extra_data, 16, buffer, offset + 2064, 4 + 8 + 172 + 104);
					return 2352;
				}

				//sync
				buffer[offset + 0] = 0x00; buffer[offset + 1] = 0xFF; buffer[offset + 2] = 0xFF; buffer[offset + 3] = 0xFF;
				buffer[offset + 4] = 0xFF; buffer[offset + 5] = 0xFF; buffer[offset + 6] = 0xFF; buffer[offset + 7] = 0xFF;
				buffer[offset + 8] = 0xFF; buffer[offset + 9] = 0xFF; buffer[offset + 10] = 0xFF; buffer[offset + 11] = 0x00;
				//sector address
				buffer[offset + 12] = bcd_aba_min;
				buffer[offset + 13] = bcd_aba_sec;
				buffer[offset + 14] = bcd_aba_frac;
				//mode 1
				buffer[offset + 15] = 1;

				//calculate EDC and poke into the sector
				uint edc = ECM.EDC_Calc(buffer, offset, 2064);
				ECM.PokeUint(buffer, 2064, edc);
				
				//intermediate
				for (int i = 0; i < 8; i++) buffer[offset + 2068 + i] = 0;
				//ECC
				ECM.ECC_Populate(buffer, offset, buffer, offset, false);

				//VALIDATION - check our homemade algorithms against code derived from ECM
				////EDC
				//GPL_ECM.edc_validateblock(buffer, 2064, buffer, offset + 2064);
				////ECC
				//GPL_ECM.ecc_validate(buffer, offset, false);
				
				//if we read the 2048 physical bytes OK, then return the complete sector
				if (read == 2048)
				{
					extra_data = new byte[16 + 4 + 8 + 172 + 104];
					Buffer.BlockCopy(buffer, 0, extra_data, 0, 16);
					Buffer.BlockCopy(buffer, 2064, extra_data, 16, 4 + 8 + 172 + 104);
					has_extra_data = true;
					return 2352;
				}
				//otherwise, return a smaller value to indicate an error
				else return read;
			}
		}

		//this is a physical 2352 byte sector.
		public class SectorEntry
		{
			public SectorEntry(ISector sec) { Sector = sec; }
			public ISector Sector;

			//todo - add some PARAMETER fields to this, so that the ISector can use them (so that each ISector doesnt have to be constructed also)
			//also then, maybe this could be a struct

			//q-subchannel stuff. can be returned directly, or built into the entire subcode sector if you want

			/// <summary>
			/// ADR and CONTROL
			/// </summary>
			public byte q_status;
			
			/// <summary>
			/// BCD indications of the current track number and index
			/// </summary>
			public BCD2 q_tno, q_index;

			/// <summary>
			/// track-relative timestamp
			/// </summary>
			public BCD2 q_min, q_sec, q_frame;
			/// <summary>
			/// absolute timestamp
			/// </summary>
			public BCD2 q_amin, q_asec, q_aframe;

			public void Read_SubchannelQ(byte[] buffer, int offset)
			{
				buffer[offset + 0] = q_status;
				buffer[offset + 1] = q_tno.BCDValue;
				buffer[offset + 2] = q_index.BCDValue;
				buffer[offset + 3] = q_min.BCDValue;
				buffer[offset + 4] = q_sec.BCDValue;
				buffer[offset + 5] = q_frame.BCDValue;
				buffer[offset + 6] = 0;
				buffer[offset + 7] = q_amin.BCDValue;
				buffer[offset + 8] = q_asec.BCDValue;
				buffer[offset + 9] = q_aframe.BCDValue;

				ushort crc16 = CRC16_CCITT.Calculate(buffer, 0, 10);
				//CRC is stored inverted and big endian
				buffer[offset + 10] = (byte)(~(crc16 >> 8));
				buffer[offset + 11] = (byte)(~(crc16));
			}
		}

		public List<IBlob> Blobs = new List<IBlob>();
		public List<SectorEntry> Sectors = new List<SectorEntry>();
		public DiscTOC TOC = new DiscTOC();

		public void Dispose()
		{
			foreach (var blob in Blobs)
			{
				blob.Dispose();
			}
		}

		void FromIsoPathInternal(string isoPath)
		{
			//make a fake cue file to represent this iso file
			const string isoCueWrapper = @"
FILE ""xarp.barp.marp.farp"" BINARY
  TRACK 01 MODE1/2048
    INDEX 01 00:00:00
";

			string cueDir = String.Empty;
			var cue = new Cue();
			CueFileResolver["xarp.barp.marp.farp"] = isoPath;
			cue.LoadFromString(isoCueWrapper);
			FromCueInternal(cue, cueDir, new CueBinPrefs());

			//var session = new DiscTOC.Session();
			//session.num = 1;
			//TOC.Sessions.Add(session);
			//var track = new DiscTOC.Track();
			//track.num = 1;
			//session.Tracks.Add(track);
			//var index = new DiscTOC.Index();
			//index.num = 0;
			//track.Indexes.Add(index);
			//index = new DiscTOC.Index();
			//index.num = 1;
			//track.Indexes.Add(index);

			//var fiIso = new FileInfo(isoPath);
			//Blob_RawFile blob = new Blob_RawFile();
			//blob.PhysicalPath = fiIso.FullName;
			//Blobs.Add(blob);
			//int num_aba = (int)(fiIso.Length / 2048);
			//track.length_aba = num_aba;
			//if (fiIso.Length % 2048 != 0)
			//  throw new InvalidOperationException("invalid iso file (size not multiple of 2048)");
			////TODO - handle this with Final Fantasy 9 cd1.iso

			//var ecmCacheBlob = new ECMCacheBlob(blob);
			//for (int i = 0; i < num_aba; i++)
			//{
			//  Sector_Mode1_2048 sector = new Sector_Mode1_2048(i+150);
			//  sector.Blob = ecmCacheBlob;
			//  sector.Offset = i * 2048;
			//  Sectors.Add(new SectorEntry(sector));
			//}

			//TOC.AnalyzeLengthsFromIndexLengths();
		}

		
		public CueBin DumpCueBin(string baseName, CueBinPrefs prefs)
		{
			if (TOC.Sessions.Count > 1)
				throw new NotSupportedException("can't dump cue+bin with more than 1 session yet");

			CueBin ret = new CueBin();
			ret.baseName = baseName;
			ret.disc = this;

			if (!prefs.OneBlobPerTrack)
			{
				//this is the preferred mode of dumping things. we will always write full sectors.
				string cue = TOC.GenerateCUE_OneBin(prefs);
				var bfd = new CueBin.BinFileDescriptor {name = baseName + ".bin"};
				ret.cue = string.Format("FILE \"{0}\" BINARY\n", bfd.name) + cue;
				ret.bins.Add(bfd);
				bfd.SectorSize = 2352;

				//skip the mandatory track 1 pregap! cue+bin files do not contain it
				for (int i = 150; i < TOC.length_aba; i++)
				{
					bfd.abas.Add(i);
					bfd.aba_zeros.Add(false);
				}
			}
			else
			{
				//we build our own cue here (unlike above) because we need to build the cue and the output dat aat the same time
				StringBuilder sbCue = new StringBuilder();
				
				for (int i = 0; i < TOC.Sessions[0].Tracks.Count; i++)
				{
					var track = TOC.Sessions[0].Tracks[i];
					var bfd = new CueBin.BinFileDescriptor
						{
							name = baseName + string.Format(" (Track {0:D2}).bin", track.num),
							SectorSize = Cue.BINSectorSizeForTrackType(track.TrackType)
						};
					ret.bins.Add(bfd);
					int aba = 0;

					//skip the mandatory track 1 pregap! cue+bin files do not contain it
					if (i == 0) aba = 150;

					for (; aba < track.length_aba; aba++)
					{
						int thisaba = track.Indexes[0].aba + aba;
						bfd.abas.Add(thisaba);
						bfd.aba_zeros.Add(false);
					}
					sbCue.AppendFormat("FILE \"{0}\" BINARY\n", bfd.name);

					sbCue.AppendFormat("  TRACK {0:D2} {1}\n", track.num, Cue.TrackTypeStringForTrackType(track.TrackType));
					foreach (var index in track.Indexes)
					{
						int x = index.aba - track.Indexes[0].aba;
						if (index.num == 0 && index.aba == track.Indexes[1].aba)
						{
						    //dont emit index 0 when it is the same as index 1, it is illegal for some reason
						}
						//else if (i==0 && index.num == 0)
						//{
						//    //don't generate the first index, it is illogical
						//}
						else
						{
							//track 1 included the lead-in at the beginning of it. sneak past that.
							//if (i == 0) x -= 150;
							sbCue.AppendFormat("    INDEX {0:D2} {1}\n", index.num, new Timestamp(x).Value);
						}
					}
				}

				ret.cue = sbCue.ToString();
			}

			return ret;
		}

		/// <summary>
		/// NOT USED RIGHT NOW. AMBIGUOUS, ANYWAY.
		/// "bin" is an ill-defined concept. 
		/// </summary>
		[Obsolete]
		void DumpBin_2352(string binPath)
		{
			byte[] temp = new byte[2352];
			//a cue's bin probably doesn't contain the first 150 sectors, so skip it
			using (FileStream fs = new FileStream(binPath, FileMode.Create, FileAccess.Write, FileShare.None))
				for (int i = 150; i < Sectors.Count; i++)
				{
					ReadLBA_2352(i, temp, 0);
					fs.Write(temp, 0, 2352);
				}
		}

		public static Disc FromCuePath(string cuePath, CueBinPrefs prefs)
		{
			var ret = new Disc();
			ret.FromCuePathInternal(cuePath, prefs);
			ret.TOC.GeneratePoints();
			ret.PopulateQSubchannel();
			return ret;
		}

		/// <summary>
		/// THIS HASNT BEEN TESTED IN A LONG TIME. DOES IT WORK?
		/// </summary>
		public static Disc FromIsoPath(string isoPath)
		{
			var ret = new Disc();
			ret.FromIsoPathInternal(isoPath);
			ret.TOC.GeneratePoints();
			ret.PopulateQSubchannel();
			return ret;
		}

		/// <summary>
		/// creates subchannel Q data track for this disc
		/// </summary>
		void PopulateQSubchannel()
		{
			int aba = 0;
			int dpIndex = 0;

			while (aba < Sectors.Count)
			{
				if (dpIndex < TOC.Points.Count - 1)
				{
					if (aba >= TOC.Points[dpIndex + 1].ABA)
					{
						dpIndex++;
					}
				}
				var dp = TOC.Points[dpIndex];

				var se = Sectors[aba];

				int control = 0;
				//choose a control byte depending on whether this is an audio or data track
				if(dp.Track.TrackType == ETrackType.Audio)
					control = (int)Q_Control.StereoNoPreEmph;
				else control = (int)Q_Control.DataUninterrupted;

				//we always use ADR=1 (mode-1 q block)
				//this could be more sophisticated but it is almost useless for emulation (only useful for catalog/ISRC numbers)
				int adr = 1;
				se.q_status = (byte)(adr | (control << 4));
				se.q_tno = BCD2.FromDecimal(dp.TrackNum);
				se.q_index = BCD2.FromDecimal(dp.IndexNum);

				int track_relative_aba = aba - dp.Track.Indexes[1].aba;
				track_relative_aba = Math.Abs(track_relative_aba);
				Timestamp track_relative_timestamp = new Timestamp(track_relative_aba);
				se.q_min = BCD2.FromDecimal(track_relative_timestamp.MIN);
				se.q_sec = BCD2.FromDecimal(track_relative_timestamp.SEC);
				se.q_frame = BCD2.FromDecimal(track_relative_timestamp.FRAC);
				Timestamp absolute_timestamp = new Timestamp(aba);
				se.q_amin = BCD2.FromDecimal(absolute_timestamp.MIN);
				se.q_asec = BCD2.FromDecimal(absolute_timestamp.SEC);
				se.q_aframe = BCD2.FromDecimal(absolute_timestamp.FRAC);

				aba++;
			}
		}

		static byte IntToBCD(int n)
		{
			int ones;
			int tens = Math.DivRem(n,10,out ones);
			return (byte)((tens<<4)|ones);
		}

		private enum Q_Control
		{
			StereoNoPreEmph = 0,
			StereoPreEmph = 1,
			MonoNoPreemph = 8,
			MonoPreEmph = 9,
			DataUninterrupted = 4,
			DataIncremental = 5,
			
			CopyProhibitedMask = 0,
			CopyPermittedMask = 2,
		}
	}

	/// <summary>
	/// encapsulates a 2 digit BCD number as used various places in the CD specs
	/// </summary>
	public struct BCD2
	{
		/// <summary>
		/// The raw BCD value. you can't do math on this number! but you may be asked to supply it to a game program.
		/// The largest number it can logically contain is 99
		/// </summary>
		public byte BCDValue;

		/// <summary>
		/// The derived decimal value. you can do math on this! the largest number it can logically contain is 99.
		/// </summary>
		public int DecimalValue
		{
			get { return (BCDValue & 0xF) + ((BCDValue >> 4) & 0xF) * 10; }
			set { BCDValue = IntToBCD(value); }
		}

		/// <summary>
		/// makes a BCD2 from a decimal number. don't supply a number > 99 or you might not like the results
		/// </summary>
		public static BCD2 FromDecimal(int d)
		{
			return new BCD2 {DecimalValue = d};
		}


		static byte IntToBCD(int n)
		{
			int ones;
			int tens = Math.DivRem(n, 10, out ones);
			return (byte)((tens << 4) | ones);
		}
	}

	public class Timestamp
	{
		/// <summary>
		/// creates timestamp of 00:00:00
		/// </summary>
		public Timestamp()
		{
			Value = "00:00:00";
		}

		/// <summary>
		/// creates a timestamp from a string in the form mm:ss:ff
		/// </summary>
		public Timestamp(string value)
		{
			Value = value;
			MIN = int.Parse(value.Substring(0, 2));
			SEC = int.Parse(value.Substring(3, 2));
			FRAC = int.Parse(value.Substring(6, 2));
			ABA = MIN * 60 * 75 + SEC * 75 + FRAC;
		}
		public readonly string Value;
		public readonly int MIN, SEC, FRAC, ABA;

		/// <summary>
		/// creates timestamp from supplied ABA
		/// </summary>
		public Timestamp(int ABA)
		{
			this.ABA = ABA;
			MIN = ABA / (60 * 75);
			SEC = (ABA / 75) % 60;
			FRAC = ABA % 75;
			Value = string.Format("{0:D2}:{1:D2}:{2:D2}", MIN, SEC, FRAC);
		}
	}

	public enum ETrackType
	{
		Mode1_2352,
		Mode1_2048,
		Mode2_2352,
		Audio
	}


	public class CueBinPrefs
	{
		/// <summary>
		/// Controls general operations: should the output be split into several blobs, or just use one?
		/// </summary>
		public bool OneBlobPerTrack;

		/// <summary>
		/// NOT SUPPORTED YET (just here as a reminder) If choosing OneBinPerTrack, you may wish to write wave files for audio tracks.
		/// </summary>
		//public bool DumpWaveFiles;

		/// <summary>
		/// turn this on to dump bins instead of just cues
		/// </summary>
		public bool ReallyDumpBin;

		/// <summary>
		/// Dump bins to bitbucket instead of disk
		/// </summary>
		public bool DumpToBitbucket;

		/// <summary>
		/// dump a .sub.q along with bins. one day we'll want to dump the entire subcode but really Q is all thats important for debugging most things
		/// </summary>
		public bool DumpSubchannelQ;

		/// <summary>
		/// generate remarks and other annotations to help humans understand whats going on, but which will confuse many cue parsers
		/// </summary>
		public bool AnnotateCue;

		/// <summary>
		/// EVIL: in theory this would attempt to generate pregap commands to save disc space, but I think this is a bad idea.
		/// it would also be useful for OneBinPerTrack mode in making wave files.
		/// HOWEVER - by the time we've loaded things up into our canonical format, we don't know which 'pregaps' are safe for turning back into pregaps
		/// Because they might sometimes contain data (gapless audio discs). So we would have to inspect a series of sectors to look for silence.
		/// And even still, the ECC information might be important. So, forget it.
		/// NEVER USE OR IMPLEMENT THIS
		/// </summary>
		//public bool PreferPregapCommand = false;

		/// <summary>
		/// some cue parsers cant handle sessions. better not emit a session command then. multi-session discs will then be broken
		/// </summary>
		public bool SingleSession;

		/// <summary>
		/// enables various extension-aware behaviours.
		/// enables auto-search for files with the same name but differing extension.
		/// enables auto-detection of situations where cue blobfiles are indicating the wrong type in the cuefile
		/// </summary>
		public bool ExtensionAware = false;

		/// <summary>
		/// whenever we have a choice, use case sensitivity in searching for files
		/// </summary>
		public bool CaseSensitive = false;

		/// <summary>
		/// DO NOT CHANGE THIS! All sectors will be written with ECM data. It's a waste of space, but it is exact. (not completely supported yet)
		/// </summary>
		public bool DumpECM = true;
	}

	/// <summary>
	/// Encapsulates an in-memory cue+bin (complete cuesheet and a little registry of files)
	/// it will be based on a disc (fro mwhich it can read sectors to avoid burning through extra memory)
	/// TODO - we must merge this with whatever reads in cue+bin
	/// </summary>
	public class CueBin
	{
		public string cue;
		public string baseName;
		public Disc disc;

		public class BinFileDescriptor
		{
			public string name;
			public List<int> abas = new List<int>();

			//todo - do we really need this? i dont think so...
			public List<bool> aba_zeros = new List<bool>();
			public int SectorSize;
		}

		public List<BinFileDescriptor> bins = new List<BinFileDescriptor>();

		//NOT SUPPORTED RIGHT NOW
		//public string CreateRedumpReport()
		//{
		//    if (disc.TOC.Sessions[0].Tracks.Count != bins.Count)
		//        throw new InvalidOperationException("Cannot generate redump report on CueBin lacking OneBinPerTrack property");
		//    StringBuilder sb = new StringBuilder();
		//    for (int i = 0; i < disc.TOC.Sessions[0].Tracks.Count; i++)
		//    {
		//        var track = disc.TOC.Sessions[0].Tracks[i];
		//        var bfd = bins[i];
				
		//        //dump the track
		//        byte[] dump = new byte[track.length_aba * 2352];
		//        //TODO ????????? post-ABA unknown
		//        //for (int aba = 0; aba < track.length_aba; aba++)
		//        //    disc.ReadLBA_2352(bfd.lbas[lba],dump,lba*2352);
		//        string crc32 = string.Format("{0:X8}", CRC32.Calculate(dump));
		//        string md5 = Util.Hash_MD5(dump, 0, dump.Length);
		//        string sha1 = Util.Hash_SHA1(dump, 0, dump.Length);

		//        int pregap = track.Indexes[1].lba - track.Indexes[0].lba;
		//        Timestamp pregap_ts = new Timestamp(pregap);
		//        Timestamp len_ts = new Timestamp(track.length_lba);
		//        sb.AppendFormat("{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\t{7}\t{8}\n", 
		//            i, 
		//            Cue.RedumpTypeStringForTrackType(track.TrackType),
		//            pregap_ts.Value,
		//            len_ts.Value,
		//            track.length_lba,
		//            track.length_lba*Cue.BINSectorSizeForTrackType(track.TrackType),
		//            crc32,
		//            md5,
		//            sha1
		//            );
		//    }
		//    return sb.ToString();
		//}

		public void Dump(string directory, CueBinPrefs prefs)
		{
			ProgressReport pr = new ProgressReport();
			Dump(directory, prefs, pr);
		}

		public void Dump(string directory, CueBinPrefs prefs, ProgressReport progress)
		{
			byte[] subQ_temp = new byte[12];
			progress.TaskCount = 2;

			progress.Message = "Generating Cue";
			progress.ProgressEstimate = 1;
			progress.ProgressCurrent = 0;
			progress.InfoPresent = true;
			string cuePath = Path.Combine(directory, baseName + ".cue");
			if (prefs.DumpToBitbucket) { }
			else File.WriteAllText(cuePath, cue);

			progress.Message = "Writing bin(s)";
			progress.TaskCurrent = 1;
			progress.ProgressEstimate = bins.Sum(bfd => bfd.abas.Count);
			progress.ProgressCurrent = 0;
			if(!prefs.ReallyDumpBin) return;

			foreach (var bfd in bins)
			{
				int sectorSize = bfd.SectorSize;
				byte[] temp = new byte[2352];
				byte[] empty = new byte[2352];
				string trackBinFile = bfd.name;
				string trackBinPath = Path.Combine(directory, trackBinFile);
				string subQPath = Path.ChangeExtension(trackBinPath, ".sub.q");
				Stream fsSubQ = null;
				Stream fs;
				if(prefs.DumpToBitbucket)
					fs = Stream.Null;
				else fs = new FileStream(trackBinPath, FileMode.Create, FileAccess.Write, FileShare.None);
				try
				{
					if (prefs.DumpSubchannelQ)
						if (prefs.DumpToBitbucket)
							fsSubQ = Stream.Null;
						else fsSubQ = new FileStream(subQPath, FileMode.Create, FileAccess.Write, FileShare.None);

					for (int i = 0; i < bfd.abas.Count; i++)
					{
						if (progress.CancelSignal) return;

						progress.ProgressCurrent++;
						int aba = bfd.abas[i];
						if (bfd.aba_zeros[i])
						{
							fs.Write(empty, 0, sectorSize);
						}
						else
						{
							if (sectorSize == 2352)
								disc.ReadABA_2352(aba, temp, 0);
							else if (sectorSize == 2048) disc.ReadABA_2048(aba, temp, 0);
							else throw new InvalidOperationException();
							fs.Write(temp, 0, sectorSize);

							//write subQ if necessary
							if (fsSubQ != null)
							{
								disc.Sectors[aba].Read_SubchannelQ(subQ_temp, 0);
								fsSubQ.Write(subQ_temp, 0, 12);
							}
						}
					}
				}
				finally
				{
					fs.Dispose();
					if (fsSubQ != null) fsSubQ.Dispose();
				}
			}
		}
	}
}