BizHawk/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Tape/TapeDataBlock.cs

using BizHawk.Common;
using System.Collections.Generic;
using System.Linq;

namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
{
	/// <summary>
	/// Represents a tape block
	/// </summary>
	public class TapeDataBlock
	{
		/// <summary>
		/// Either the TZX block ID, or -1 in the case of non-tzx blocks
		/// </summary>
		private int _blockID = -1;
		public int BlockID
		{
			get => _blockID;
			set
			{
				_blockID = value;
				MetaData ??= new Dictionary<BlockDescriptorTitle, string>();
				AddMetaData(BlockDescriptorTitle.Block_ID, value.ToString());
			}
		}

		/// <summary>
		/// The block type
		/// </summary>
		private BlockType _blockType;
		public BlockType BlockDescription
		{
			get => _blockType;
			set
			{
				_blockType = value;
				MetaData ??= new Dictionary<BlockDescriptorTitle, string>();
			}
		}

		/// <summary>
		/// Byte array containing the raw block data
		/// </summary>
		private byte[] _blockData;
		public byte[] BlockData
		{
			get => _blockData;
			set => _blockData = value;
		}

		#region Block Meta Data

		/// <summary>
		/// Dictionary of block related data
		/// </summary>
		public Dictionary<BlockDescriptorTitle, string> MetaData { get; set; }

		/// <summary>
		/// Adds a single metadata item to the Dictionary
		/// </summary>
		public void AddMetaData(BlockDescriptorTitle descriptor, string data)
		{
			// check whether entry already exists
			bool check = MetaData.ContainsKey(descriptor);
			if (check)
			{
				// already exists - update
				MetaData[descriptor] = data;
			}
			else
			{
				// create new
				MetaData.Add(descriptor, data);
			}
		}

		#endregion

		/// <summary>
		/// List containing the pulse timing values
		/// </summary>
		public List<int> DataPeriods = new List<int>();

		public bool InitialPulseLevel;

		/// <summary>
		/// Command that is raised by this data block
		/// (that may or may not need to be acted on)
		/// </summary>
		private TapeCommand _command = TapeCommand.NONE;
		public TapeCommand Command
		{
			get => _command;
			set => _command = value;
		}

		/// <summary>
		/// The defined post-block pause
		/// </summary>
		private int _pauseInMS;
		public int PauseInMS
		{
			get => _pauseInMS;
			set => _pauseInMS = value;
		}


		/// <summary>
		/// Returns the data periods as an array
		/// (primarily to aid in bizhawk state serialization)
		/// </summary>
		public int[] GetDataPeriodsArray()
		{
			return DataPeriods.ToArray();
		}

		/// <summary>
		/// Accepts an array of data periods and updates the DataPeriods list accordingly
		/// (primarily to aid in bizhawk state serialization)
		/// </summary>
		public void SetDataPeriodsArray(int[] periodArray)
		{
			DataPeriods = periodArray?.ToList() ?? new List<int>();
		}

		/// <summary>
		/// Bizhawk state serialization
		/// </summary>
		public void SyncState(Serializer ser, int blockPosition)
		{
			ser.BeginSection("DataBlock" + blockPosition);

			ser.Sync(nameof(_blockID), ref _blockID);
			ser.SyncEnum(nameof(_blockType), ref _blockType);
			ser.Sync(nameof(_blockData), ref _blockData, true);
			ser.SyncEnum(nameof(_command), ref _command);

			int[] tempArray = null;

			if (ser.IsWriter)
			{
				tempArray = GetDataPeriodsArray();
				ser.Sync("_periods", ref tempArray, true);
			}
			else
			{
				ser.Sync("_periods", ref tempArray, true);
				SetDataPeriodsArray(tempArray);
			}

			ser.EndSection();
		}
	}

	/// <summary>
	/// The types of TZX blocks
	/// </summary>
	public enum BlockType
	{
		Standard_Speed_Data_Block = 0x10,
		Turbo_Speed_Data_Block = 0x11,
		Pure_Tone = 0x12,
		Pulse_Sequence = 0x13,
		Pure_Data_Block = 0x14,
		Direct_Recording = 0x15,
		CSW_Recording = 0x18,
		Generalized_Data_Block = 0x19,
		Pause_or_Stop_the_Tape = 0x20,
		Group_Start = 0x21,
		Group_End = 0x22,
		Jump_to_Block = 0x23,
		Loop_Start = 0x24,
		Loop_End = 0x25,
		Call_Sequence = 0x26,
		Return_From_Sequence = 0x27,
		Select_Block = 0x28,
		Stop_the_Tape_48K = 0x2A,
		Set_Signal_Level = 0x2B,
		Text_Description = 0x30,
		Message_Block = 0x31,
		Archive_Info = 0x32,
		Hardware_Type = 0x33,
		Custom_Info_Block = 0x35,
		Glue_Block = 0x5A,

		// depreciated blocks
		C64_ROM_Type_Data_Block = 0x16,
		C64_Turbo_Tape_Data_Block = 0x17,
		Emulation_Info = 0x34,
		Snapshot_Block = 0x40,

		// unsupported / undetected
		Unsupported,

		// PZX blocks
		PZXT,
		PULS,
		DATA,
		BRWS,
		PAUS,

		// zxhawk proprietry
		PAUSE_BLOCK,

		WAV_Recording
	}


	/// <summary>
	/// Different title possibilities
	/// </summary>
	public enum BlockDescriptorTitle
	{
		Undefined,
		Block_ID,
		Program,
		Data_Bytes,
		Bytes,

		Pilot_Pulse_Length,
		Pilot_Pulse_Count,
		First_Sync_Length,
		Second_Sync_Length,
		Zero_Bit_Length,
		One_Bit_Length,
		Data_Length,
		Bits_In_Last_Byte,
		Pause_After_Data,

		Pulse_Length,
		Pulse_Count,

		Text_Description,
		Title,
		Publisher,
		Author,
		Year,
		Language,
		Type,
		Price,
		Protection,
		Origin,
		Comments,

		Needs_Parsing
	}
}