From 7771b968c90363a181864eb55b662a87cb5a7d3f Mon Sep 17 00:00:00 2001
From: adelikat <adelikat@tasvideos.org>
Date: Sat, 29 Feb 2020 11:46:45 -0600
Subject: [PATCH] Move saturn gameshark parsing to its own class

---
 .../cheats/PsxGameSharkDecoder.cs             |  2 +
 .../cheats/SaturnGameSharkDecoder.cs          | 55 +++++++++++++++++++
 BizHawk.Client.EmuHawk/tools/GameShark.cs     | 32 ++---------
 3 files changed, 61 insertions(+), 28 deletions(-)
 create mode 100644 BizHawk.Client.Common/cheats/SaturnGameSharkDecoder.cs

diff --git a/BizHawk.Client.Common/cheats/PsxGameSharkDecoder.cs b/BizHawk.Client.Common/cheats/PsxGameSharkDecoder.cs
index dbc5bf0477..89c5272ab0 100644
--- a/BizHawk.Client.Common/cheats/PsxGameSharkDecoder.cs
+++ b/BizHawk.Client.Common/cheats/PsxGameSharkDecoder.cs
@@ -16,6 +16,8 @@ namespace BizHawk.Client.Common.cheats
 
 		public int Address { get; private set; }
 		public int Value { get; private set; }
+
+		// TODO: WatchSize
 		public int ByteSize { get; private set; } = 1;
 
 		// 30XXXXXX 00YY
diff --git a/BizHawk.Client.Common/cheats/SaturnGameSharkDecoder.cs b/BizHawk.Client.Common/cheats/SaturnGameSharkDecoder.cs
new file mode 100644
index 0000000000..41d8cfc75d
--- /dev/null
+++ b/BizHawk.Client.Common/cheats/SaturnGameSharkDecoder.cs
@@ -0,0 +1,55 @@
+using System;
+using System.Globalization;
+
+namespace BizHawk.Client.Common.cheats
+{
+	public class SaturnGameSharkDecoder
+	{
+		private readonly string _code;
+
+		public SaturnGameSharkDecoder(string code)
+		{
+			_code = code;
+			Decode();
+		}
+
+		public int Address { get; private set; }
+		public int Value { get; private set; }
+		public WatchSize Size { get; private set; } = WatchSize.Word;
+
+		// Sample Input for Saturn:
+		// 160949FC 0090
+		// Address: 0949FC
+		// Value:  90
+		// Note, 3XXXXXXX are Big Endian
+		// Remove first two octets
+		public void Decode()
+		{
+			if (_code == null)
+			{
+				throw new ArgumentNullException(nameof(_code));
+			}
+
+			if (_code.IndexOf(" ") != 8)
+			{
+				throw new InvalidOperationException("All Saturn GameShark Codes need to contain a space after the eighth character.");
+			}
+
+			if (_code.Length != 13)
+			{
+				throw new InvalidOperationException("All Saturn GameShark Cheats need to be 13 characters in length.");
+			}
+
+			//  Only the first character really matters?  16 or 36?
+			var test = _code.Remove(2, 11).Remove(1, 1);
+			if (test == "3")
+			{
+				Size = WatchSize.Byte;
+			}
+			
+			var s = _code.Remove(0, 2);
+			Address = int.Parse(s.Remove(6, 5), NumberStyles.HexNumber);
+			Value = int.Parse(s.Remove(0, 7));
+		}
+	}
+}
diff --git a/BizHawk.Client.EmuHawk/tools/GameShark.cs b/BizHawk.Client.EmuHawk/tools/GameShark.cs
index 584db1c940..49a09c105e 100644
--- a/BizHawk.Client.EmuHawk/tools/GameShark.cs
+++ b/BizHawk.Client.EmuHawk/tools/GameShark.cs
@@ -2461,10 +2461,7 @@ namespace BizHawk.Client.EmuHawk
 			switch (test)
 			{
 				case "1":
-					_byteSize = 16;
-					break;
 				case "3":
-					_byteSize = 8;
 					break;
 				// 0 writes once.
 				case "0":
@@ -2480,34 +2477,13 @@ namespace BizHawk.Client.EmuHawk
 					return;
 			}
 
-			// Sample Input for Saturn:
-			// 160949FC 0090
-			// Address: 0949FC
-			// Value:  90
-			// Note, 3XXXXXXX are Big Endian
-			// Remove first two octets
-			var parseString = cheat.Remove(0, 2);
-
-			// Get RAM Address
-			_ramAddress = parseString.Remove(6, 5);
-
-			// Get RAM Value
-			_ramValue = parseString.Remove(0, 7);
 			try
 			{
-				// A Watch needs to be generated so we can make a cheat out of that.  This is due to how the Cheat engine works.
-				// System Bus Domain, The Address to Watch, Byte size (Word), Hex Display, Description.  Big Endian.
+				var decoder = new SaturnGameSharkDecoder(cheat);
+				
 				// My Concern is that Work RAM High may be incorrect?
-				if (_byteSize == 8)
-				{
-					var watch = Watch.GenerateWatch(MemoryDomains["Work Ram High"], long.Parse(_ramAddress, NumberStyles.HexNumber), WatchSize.Byte, Common.DisplayType.Hex, true, txtDescription.Text);
-					Global.CheatList.Add(new Cheat(watch, int.Parse(_ramValue, NumberStyles.HexNumber)));
-				}
-				else if (_byteSize == 16)
-				{
-					var watch = Watch.GenerateWatch(MemoryDomains["Work Ram High"], long.Parse(_ramAddress, NumberStyles.HexNumber), WatchSize.Word, Common.DisplayType.Hex, true, txtDescription.Text);
-					Global.CheatList.Add(new Cheat(watch, int.Parse(_ramValue, NumberStyles.HexNumber)));
-				}
+				var watch = Watch.GenerateWatch(MemoryDomains["Work Ram High"], decoder.Address, decoder.Size, Common.DisplayType.Hex, true, txtDescription.Text);
+				Global.CheatList.Add(new Cheat(watch, decoder.Value));
 			}
 			catch (Exception ex)
 			{