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

namespace BizHawk.MultiClient
{
	public class RamSearchEngine
	{
		public enum ComparisonOperator { Equal, GreaterThan, GreaterThanEqual, LessThan, LessThanEqual, NotEqual, DifferentBy };
		public enum Compare { Previous, SpecificValue, SpecificAddress, Changes, Difference }
		
		private int? _differentBy = null;
		private Compare _compareTo = Compare.Previous;
		private long? _compareValue = null;
		private ComparisonOperator _operator = ComparisonOperator.Equal;

		private List<IMiniWatch> _watchList = new List<IMiniWatch>();
		private Settings _settings = new Settings();
		private WatchHistory _history = new WatchHistory(true);
		private bool _keepHistory = true;

		public RamSearchEngine(Settings settings)
		{
			_settings.Mode = settings.Mode;
			_settings.Domain = settings.Domain;
			_settings.Size = settings.Size;
			_settings.CheckMisAligned = settings.CheckMisAligned;
			_settings.Type = settings.Type;
			_settings.BigEndian = settings.BigEndian;
			_settings.PreviousType = settings.PreviousType;
		}

		#region API

		public void Start()
		{
			_watchList.Clear();
			_history.Clear();
			switch (_settings.Size)
			{
				default:
				case Watch.WatchSize.Byte:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						for (int i = 0; i < _settings.Domain.Size; i++)
						{
							_watchList.Add(new MiniByteWatchDetailed(_settings.Domain, i));
						}
					}
					else
					{
						for (int i = 0; i < _settings.Domain.Size; i++)
						{
							_watchList.Add(new MiniByteWatch(_settings.Domain, i));
						}
					}
					break;
				case Watch.WatchSize.Word:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						for (int i = 0; i < _settings.Domain.Size; i += (_settings.CheckMisAligned ? 1 : 2))
						{
							_watchList.Add(new MiniWordWatchDetailed(_settings.Domain, i, _settings.BigEndian));
						}
					}
					else
					{
						for (int i = 0; i < _settings.Domain.Size; i += (_settings.CheckMisAligned ? 1 : 2))
						{
							_watchList.Add(new MiniWordWatch(_settings.Domain, i, _settings.BigEndian));
						}
					}
					break;
				case Watch.WatchSize.DWord:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						for (int i = 0; i < _settings.Domain.Size; i += (_settings.CheckMisAligned ? 1 : 4))
						{
							_watchList.Add(new MiniDWordWatchDetailed(_settings.Domain, i, _settings.BigEndian));
						}
					}
					else
					{
						for (int i = 0; i < _settings.Domain.Size; i += (_settings.CheckMisAligned ? 1 : 4))
						{
							_watchList.Add(new MiniDWordWatch(_settings.Domain, i, _settings.BigEndian));
						}
					}
					break;
			}

			if (_keepHistory)
			{
				_history.AddState(_watchList);
			}
		}

		/// <summary>
		/// Exposes the current watch state based on index
		/// </summary>
		public Watch this[int index]
		{
			get
			{
				if (_settings.Mode == Settings.SearchMode.Detailed)
				{
					return Watch.GenerateWatch(
						_settings.Domain,
						_watchList[index].Address,
						_settings.Size,
						_settings.Type,
						_settings.BigEndian,
						_watchList[index].Previous,
						(_watchList[index] as IMiniWatchDetails).ChangeCount
					);
				}
				else
				{
					return Watch.GenerateWatch(
						_settings.Domain,
						_watchList[index].Address,
						_settings.Size,
						_settings.Type,
						_settings.BigEndian,
						_watchList[index].Previous,
						0
					);
				}
			}
		}

		public int DoSearch()
		{
			int before = _watchList.Count;
			
			switch (_compareTo)
			{
				default:
				case RamSearchEngine.Compare.Previous:
					_watchList = ComparePrevious(_watchList).ToList();
					break;
				case RamSearchEngine.Compare.SpecificValue:
					_watchList = CompareSpecificValue(_watchList).ToList();
					break;
				case RamSearchEngine.Compare.SpecificAddress:
					_watchList = CompareSpecificAddress(_watchList).ToList();
					break;
				case RamSearchEngine.Compare.Changes:
					_watchList = CompareChanges(_watchList).ToList();
					break;
				case RamSearchEngine.Compare.Difference:
					_watchList = CompareDifference(_watchList).ToList();
					break;
			}

			if (_settings.PreviousType == Watch.PreviousType.LastSearch)
			{
				SetPrevousToCurrent();
			}

			if (_keepHistory)
			{
				_history.AddState(_watchList);
			}

			return before - _watchList.Count;
		}

		public bool Preview(int address)
		{
			switch (_compareTo)
			{
				default:
				case RamSearchEngine.Compare.Previous:
					return ComparePrevious(_watchList.Where(x => x.Address == address)).Count() == 0;
				case RamSearchEngine.Compare.SpecificValue:
					return CompareSpecificValue(_watchList.Where(x => x.Address == address)).Count() == 0;
				case RamSearchEngine.Compare.SpecificAddress:
					return CompareSpecificAddress(_watchList.Where(x => x.Address == address)).Count() == 0;
				case RamSearchEngine.Compare.Changes:
					return CompareChanges(_watchList.Where(x => x.Address == address)).Count() == 0;
				case RamSearchEngine.Compare.Difference:
					return CompareDifference(_watchList.Where(x => x.Address == address)).Count() == 0;
			}
		}

		public int Count
		{
			get { return _watchList.Count; }
		}

		public Settings.SearchMode Mode { get { return _settings.Mode; } }

		public MemoryDomain Domain
		{
			get { return _settings.Domain; }
		}

		public Compare CompareTo
		{
			get { return _compareTo; }
			set
			{
				if (CanDoCompareType(value))
				{
					_compareTo = value;
				}
				else
				{
					throw new InvalidOperationException();
				}
			}
		}

		public long? CompareValue
		{
			get { return _compareValue; }
			set { _compareValue = value; }
		}

		public ComparisonOperator Operator
		{
			get { return _operator; }
			set { _operator = value; }
		}

		public int? DifferentBy
		{
			get { return _differentBy; }
			set { _differentBy = value; }
		}

		public void Update()
		{
			if (_settings.Mode == Settings.SearchMode.Detailed)
			{
				foreach (IMiniWatchDetails watch in _watchList)
				{
					watch.Update(_settings.PreviousType, _settings.Domain, _settings.BigEndian);
				}
			}
			else
			{
				return;
			}
		}

		public void SetType(Watch.DisplayType type)
		{
			if (Watch.AvailableTypes(_settings.Size).Contains(type))
			{
				_settings.Type = type;
			}
			else
			{
				throw new InvalidOperationException();
			}
		}

		public void SetEndian(bool bigendian)
		{
			_settings.BigEndian = bigendian;
		}

		public void SetPreviousType(Watch.PreviousType type)
		{
			if (type == Watch.PreviousType.LastChange)
			{
				throw new InvalidOperationException();
			}

			if (_settings.Mode == Settings.SearchMode.Fast)
			{
				if (type == Watch.PreviousType.LastFrame)
				{
					throw new InvalidOperationException();
				}
			}

			_settings.PreviousType = type;
		}

		public void SetPrevousToCurrent()
		{
			_watchList.ForEach(x => x.SetPreviousToCurrent(_settings.Domain, _settings.BigEndian));
		}

		public void ClearChangeCounts()
		{
			if (_settings.Mode == Settings.SearchMode.Detailed)
			{
				foreach (IMiniWatchDetails watch in _watchList.Cast<IMiniWatchDetails>())
				{
					watch.ClearChangeCount();
				}
			}
		}

		public void RemoveRange(List<int> addresses)
		{
			_watchList = _watchList.Where(x => !addresses.Contains(x.Address)).ToList();
		}

		public void AddRange(List<int> addresses, bool append)
		{
			if (!append)
			{
				_watchList.Clear();
			}

			switch(_settings.Size)
			{
				default:
				case Watch.WatchSize.Byte:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						foreach(var addr in addresses) { _watchList.Add(new MiniByteWatchDetailed(_settings.Domain, addr)); }
					}
					else
					{
						foreach(var addr in addresses) { _watchList.Add(new MiniByteWatch(_settings.Domain, addr)); }
					}
					break;
				case Watch.WatchSize.Word:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						foreach (var addr in addresses) { _watchList.Add(new MiniWordWatchDetailed(_settings.Domain, addr, _settings.BigEndian)); }
					}
					else
					{
						foreach (var addr in addresses) { _watchList.Add(new MiniWordWatch(_settings.Domain, addr, _settings.BigEndian)); }
					}
					break;
				case Watch.WatchSize.DWord:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						foreach (var addr in addresses) { _watchList.Add(new MiniDWordWatchDetailed(_settings.Domain, addr, _settings.BigEndian)); }
					}
					else
					{
						foreach (var addr in addresses) { _watchList.Add(new MiniDWordWatch(_settings.Domain, addr, _settings.BigEndian)); }
					}
					break;
			}
		}

		public void Sort(string column, bool reverse)
		{
			switch(column)
			{
				case RamSearch.ADDRESS:
					if (reverse)
					{
						_watchList = _watchList.OrderByDescending(x => x.Address).ToList();
					}
					else
					{
						_watchList = _watchList.OrderBy(x => x.Address).ToList();
					}
					break;
				case RamSearch.VALUE:
					if (reverse)
					{
						_watchList = _watchList.OrderByDescending(x => GetValue(x.Address)).ToList();
					}
					else
					{
						_watchList = _watchList.OrderBy(x => GetValue(x.Address)).ToList();
					}
					break;
				case RamSearch.PREV:
					if (reverse)
					{
						_watchList = _watchList.OrderByDescending(x => x.Previous).ToList();
					}
					else
					{
						_watchList = _watchList.OrderBy(x => x.Previous).ToList();
					}
					break;
				case RamSearch.CHANGES:
					if (_settings.Mode == Settings.SearchMode.Detailed)
					{
						if (reverse)
						{
							_watchList = _watchList
								.Cast<IMiniWatchDetails>()
								.OrderByDescending(x => x.ChangeCount)
								.Cast<IMiniWatch>().ToList();
						}
						else
						{
							_watchList = _watchList
								.Cast<IMiniWatchDetails>()
								.OrderBy(x => x.ChangeCount)
								.Cast<IMiniWatch>().ToList();
						}
					}
					break;
				case RamSearch.DIFF:
					if (reverse)
					{
						_watchList = _watchList.OrderByDescending(x => (GetValue(x.Address) - x.Previous)).ToList();
					}
					else
					{
						_watchList = _watchList.OrderBy(x => (GetValue(x.Address) - x.Previous)).ToList();
					}
					break;
			}
		}

		#endregion
		
		#region Undo API

		public bool UndoEnabled
		{
			get { return _keepHistory; }
			set { _keepHistory = value; }
		}

		public bool CanUndo
		{
			get { return _keepHistory && _history.CanUndo; }
		}

		public bool CanRedo
		{
			get { return _keepHistory && _history.CanRedo; }
		}
		
		public void ClearHistory()
		{
			_history.Clear();
		}

		public void Undo()
		{
			if (_keepHistory)
			{
				_watchList = _history.Undo();
			}
		}

		public void Redo()
		{
			if (_keepHistory)
			{
				_watchList = _history.Redo();
			}
		}

		#endregion

		#region Comparisons

		private IEnumerable<IMiniWatch> ComparePrevious(IEnumerable<IMiniWatch> watchList)
		{
			switch (_operator)
			{
				default:
				case ComparisonOperator.Equal:
					return watchList.Where(x => GetValue(x.Address) == x.Previous);
				case ComparisonOperator.NotEqual:
					return watchList.Where(x => GetValue(x.Address) != x.Previous);
				case ComparisonOperator.GreaterThan:
					return watchList.Where(x => GetValue(x.Address) > x.Previous);
				case ComparisonOperator.GreaterThanEqual:
					return watchList.Where(x => GetValue(x.Address) >= x.Previous);
				case ComparisonOperator.LessThan:
					return watchList.Where(x => GetValue(x.Address) < x.Previous);
				case ComparisonOperator.LessThanEqual:
					return watchList.Where(x => GetValue(x.Address) <= x.Previous);
				case ComparisonOperator.DifferentBy:
					if (_differentBy.HasValue)
					{
						return watchList.Where(x => (GetValue(x.Address) + _differentBy.Value == x.Previous) || (GetValue(x.Address) - _differentBy.Value == x.Previous));
					}
					else
					{
						throw new InvalidOperationException();
					}
					
			}
		}

		private IEnumerable<IMiniWatch> CompareSpecificValue(IEnumerable<IMiniWatch> watchList)
		{
			if (_compareValue.HasValue)
			{
				switch (_operator)
				{
					default:
					case ComparisonOperator.Equal:
						return watchList.Where(x => GetValue(x.Address) == _compareValue.Value);
					case ComparisonOperator.NotEqual:
						return watchList.Where(x => GetValue(x.Address) != _compareValue.Value);
					case ComparisonOperator.GreaterThan:
						return watchList.Where(x =>  GetValue(x.Address) > _compareValue.Value);
					case ComparisonOperator.GreaterThanEqual:
						return watchList.Where(x => GetValue(x.Address) >= _compareValue.Value);
					case ComparisonOperator.LessThan:
						return watchList.Where(x => GetValue(x.Address) < _compareValue.Value);
					case ComparisonOperator.LessThanEqual:
						return watchList.Where(x => GetValue(x.Address) <= _compareValue.Value);
					case ComparisonOperator.DifferentBy:
						if (_differentBy.HasValue)
						{
							return watchList.Where(x => (GetValue(x.Address) + _differentBy.Value == _compareValue.Value) || (GetValue(x.Address) - _differentBy.Value == _compareValue.Value));
						}
						else
						{
							throw new InvalidOperationException();
						}
				}
			}
			else
			{
				throw new InvalidOperationException();
			}
		}

		private IEnumerable<IMiniWatch> CompareSpecificAddress(IEnumerable<IMiniWatch> watchList)
		{
			if (_compareValue.HasValue)
			{
				switch (_operator)
				{
					default:
					case ComparisonOperator.Equal:
						return watchList.Where(x => x.Address == _compareValue.Value);
					case ComparisonOperator.NotEqual:
						return watchList.Where(x => x.Address != _compareValue.Value);
					case ComparisonOperator.GreaterThan:
						return watchList.Where(x => x.Address > _compareValue.Value);
					case ComparisonOperator.GreaterThanEqual:
						return watchList.Where(x => x.Address >= _compareValue.Value);
					case ComparisonOperator.LessThan:
						return watchList.Where(x => x.Address < _compareValue.Value);
					case ComparisonOperator.LessThanEqual:
						return watchList.Where(x => x.Address <= _compareValue.Value);
					case ComparisonOperator.DifferentBy:
						if (_differentBy.HasValue)
						{
							return watchList.Where(x => (x.Address + _differentBy.Value == _compareValue.Value) || (x.Address - _differentBy.Value == _compareValue.Value));
						}
						else
						{
							throw new InvalidOperationException();
						}
				}
			}
			else
			{
				throw new InvalidOperationException();
			}
		}

		private IEnumerable<IMiniWatch> CompareChanges(IEnumerable<IMiniWatch> watchList)
		{
			if (_settings.Mode == Settings.SearchMode.Detailed && _compareValue.HasValue)
			{
				switch (_operator)
				{
					default:
					case ComparisonOperator.Equal:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount == _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.NotEqual:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount != _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.GreaterThan:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount > _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.GreaterThanEqual:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount >= _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.LessThan:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount < _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.LessThanEqual:
						return watchList
							.Cast<IMiniWatchDetails>()
							.Where(x => x.ChangeCount <= _compareValue.Value)
							.Cast<IMiniWatch>();
					case ComparisonOperator.DifferentBy:
						if (_differentBy.HasValue)
						{
							return watchList
								.Cast<IMiniWatchDetails>()
								.Where(x => (x.ChangeCount + _differentBy.Value == _compareValue.Value) || (x.ChangeCount - _differentBy.Value == _compareValue.Value))
								.Cast<IMiniWatch>();
						}
						else
						{
							throw new InvalidOperationException();
						}
				}
			}
			else
			{
				throw new InvalidCastException();
			}
		}

		private IEnumerable<IMiniWatch> CompareDifference(IEnumerable<IMiniWatch> watchList)
		{
			if (_compareValue.HasValue)
			{
				switch (_operator)
				{
					default:
					case ComparisonOperator.Equal:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) == _compareValue.Value);
					case ComparisonOperator.NotEqual:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) != _compareValue.Value);
					case ComparisonOperator.GreaterThan:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) > _compareValue.Value);
					case ComparisonOperator.GreaterThanEqual:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) >= _compareValue.Value);
					case ComparisonOperator.LessThan:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) < _compareValue.Value);
					case ComparisonOperator.LessThanEqual:
						return watchList.Where(x => (GetValue(x.Address) - x.Previous) <= _compareValue.Value);
					case ComparisonOperator.DifferentBy:
						if (_differentBy.HasValue)
						{
							return watchList.Where(x => (GetValue(x.Address) - x.Previous + _differentBy.Value == _compareValue) || (GetValue(x.Address) - x.Previous - _differentBy.Value == x.Previous));
						}
						else
						{
							throw new InvalidOperationException();
						}
				}
			}
			else
			{
				throw new InvalidCastException();
			}
		}

		#endregion

		#region Private parts

		private long GetValue(int addr)
		{
			switch (_settings.Size)
			{
				default:
				case Watch.WatchSize.Byte:
					var theByte = _settings.Domain.PeekByte(addr);
					if (_settings.Type == Watch.DisplayType.Signed)
					{
						return (sbyte)theByte;
					}
					else
					{
						return theByte;
					}
				case Watch.WatchSize.Word:
					var theWord = _settings.Domain.PeekWord(addr, _settings.BigEndian ? Endian.Big : Endian.Little);
					if (_settings.Type == Watch.DisplayType.Signed)
					{
						return (short)theWord;
					}
					else
					{
						return theWord;
					}
				case Watch.WatchSize.DWord:
					var theDWord = _settings.Domain.PeekDWord(addr, _settings.BigEndian ? Endian.Big : Endian.Little);
					if (_settings.Type == Watch.DisplayType.Signed)
					{
						return (int)theDWord;
					}
					else
					{
						return (uint)theDWord;
					}
			}
		}

		private bool CanDoCompareType(Compare compareType)
		{
			switch (_settings.Mode)
			{
				default:
				case Settings.SearchMode.Detailed:
					return true;
				case Settings.SearchMode.Fast:
					return !(compareType == Compare.Changes);
			}
		}

		#endregion

		#region Classes

		public interface IMiniWatch
		{
			int Address { get; }
			int Previous { get; }
			void SetPreviousToCurrent(MemoryDomain domain, bool bigendian);
		}

		private interface IMiniWatchDetails
		{
			int ChangeCount { get; }
			
			void ClearChangeCount();
			void Update(Watch.PreviousType type, MemoryDomain domain, bool bigendian);
		}

		private class MiniByteWatch : IMiniWatch
		{
			public int Address { get; private set; }
			private byte _previous;

			public MiniByteWatch(MemoryDomain domain, int addr)
			{
				Address = addr;
				SetPreviousToCurrent(domain, false);
			}

			public int Previous
			{
				get { return _previous; }
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekByte(Address);
			}
		}

		private class MiniWordWatch : IMiniWatch
		{
			public int Address { get; private set; }
			private ushort _previous;

			public MiniWordWatch(MemoryDomain domain, int addr, bool bigEndian)
			{
				Address = addr;
				SetPreviousToCurrent(domain, bigEndian);
			}

			public int Previous
			{
				get { return _previous; }
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekWord(Address, bigendian ? Endian.Big : Endian.Little);
			}
		}

		public class MiniDWordWatch : IMiniWatch
		{
			public int Address { get; private set; }
			private uint _previous;

			public MiniDWordWatch(MemoryDomain domain, int addr, bool bigEndian)
			{
				Address = addr;
				SetPreviousToCurrent(domain, bigEndian);
			}

			public int Previous
			{
				get { return (int)_previous; }
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekDWord(Address, bigendian ? Endian.Big : Endian.Little);
			}
		}

		private sealed class MiniByteWatchDetailed : IMiniWatch, IMiniWatchDetails
		{
			public int Address { get; private set; }
			private byte _previous;
			int _changecount = 0;

			public MiniByteWatchDetailed(MemoryDomain domain, int addr)
			{
				Address = addr;
				SetPreviousToCurrent(domain, false);
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekByte(Address);
			}

			public int Previous
			{
				get { return _previous; }
			}

			public int ChangeCount
			{
				get { return _changecount; }
			}

			public void Update(Watch.PreviousType type, MemoryDomain domain, bool bigendian)
			{
				byte value = domain.PeekByte(Address);
				if (value != Previous)
				{
					_changecount++;
				}

				switch (type)
				{
					case Watch.PreviousType.Original:
					case Watch.PreviousType.LastSearch:
						break;
					case Watch.PreviousType.LastFrame:
						_previous = value;
						break;
				}
			}

			public void ClearChangeCount()
			{
				_changecount = 0;
			}
		}

		private sealed class MiniWordWatchDetailed : IMiniWatch, IMiniWatchDetails
		{
			public int Address { get; private set; }
			private ushort _previous;
			int _changecount = 0;

			public MiniWordWatchDetailed(MemoryDomain domain, int addr, bool bigEndian)
			{
				Address = addr;
				SetPreviousToCurrent(domain, bigEndian);
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekWord(Address, bigendian ? Endian.Big : Endian.Little);
			}

			public int Previous
			{
				get { return _previous; }
			}

			public int ChangeCount
			{
				get { return _changecount; }
			}

			public void Update(Watch.PreviousType type, MemoryDomain domain, bool bigendian)
			{
				ushort value = domain.PeekWord(Address, bigendian ? Endian.Big : Endian.Little);
				if (value != Previous)
				{
					_changecount++;
				}
				switch (type)
				{
					case Watch.PreviousType.Original:
					case Watch.PreviousType.LastSearch:
						break;
					case Watch.PreviousType.LastFrame:
						_previous = value;
						break;
				}
			}

			public void ClearChangeCount()
			{
				_changecount = 0;
			}
		}

		public sealed class MiniDWordWatchDetailed : IMiniWatch, IMiniWatchDetails
		{
			public int Address { get; private set; }
			private uint _previous;
			int _changecount = 0;

			public MiniDWordWatchDetailed(MemoryDomain domain, int addr, bool bigEndian)
			{
				Address = addr;
				SetPreviousToCurrent(domain, bigEndian);
			}

			public void SetPreviousToCurrent(MemoryDomain domain, bool bigendian)
			{
				_previous = domain.PeekDWord(Address, bigendian ? Endian.Big : Endian.Little);
			}

			public int Previous
			{
				get { return (int)_previous; }
			}

			public int ChangeCount
			{
				get { return _changecount; }
			}

			public void Update(Watch.PreviousType type, MemoryDomain domain, bool bigendian)
			{
				uint value = domain.PeekDWord(Address, bigendian ? Endian.Big : Endian.Little);
				if (value != Previous)
				{
					_changecount++;
				}
				switch (type)
				{
					case Watch.PreviousType.Original:
					case Watch.PreviousType.LastSearch:
						break;
					case Watch.PreviousType.LastFrame:
						_previous = value;
						break;
				}
			}

			public void ClearChangeCount()
			{
				_changecount = 0;
			}
		}

		public class Settings
		{
			/*Require restart*/
			public enum SearchMode { Fast, Detailed }

			public SearchMode Mode = SearchMode.Detailed;
			public MemoryDomain Domain = Global.Emulator.MainMemory;
			public Watch.WatchSize Size = Watch.WatchSize.Byte;
			public bool CheckMisAligned = false;

			/*Can be changed mid-search*/
			public Watch.DisplayType Type = Watch.DisplayType.Unsigned;
			public bool BigEndian = false;
			public Watch.PreviousType PreviousType = Watch.PreviousType.LastSearch;
		}

		#endregion
	}
}