- IToolForm: Added RequiredServices attribute to define dependencies, and added EmulatorServices for ToolManager to supply them.

- IServiceProvider, BasicServiceProvider: Added compile-time unknown type versions of GetService and HasService.
- ToolManager: Added IsAvailable to test whether all dependencies for a tool are available.

BizHawk.Client.EmuHawk/config/NES/NESSoundConfig.cs

@@ -1,6 +1,6 @@
 using System;
+using System.Collections.Generic;
 using System.Windows.Forms;
-
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Nintendo.NES;
 
@@ -11,6 +11,8 @@ namespace BizHawk.Client.EmuHawk
 		private NES.NESSettings _oldSettings;
 		private NES.NESSettings _settings;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public bool AskSaveChanges() { return true; }
 		public bool UpdateBefore { get { return false; } }
 		public void UpdateValues()

BizHawk.Client.EmuHawk/tools/Atari2600/Atari2600Debugger.cs

@@ -25,6 +25,8 @@ namespace BizHawk.Client.EmuHawk
 		// Video Frame advance
 		// Add to toolbox
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private Atari2600 _core = Global.Emulator as Atari2600;
 		private readonly List<string> _instructions = new List<string>();
 

BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs

@@ -19,6 +19,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class Cheats : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public const string NAME = "NamesColumn";
 		public const string ADDRESS = "AddressColumn";
 		public const string VALUE = "ValueColumn";

BizHawk.Client.EmuHawk/tools/Debugger/GenericDebugger.cs

@@ -21,6 +21,8 @@ namespace BizHawk.Client.EmuHawk
 		private IDebuggable Core;
 		private IDisassemblable Disassembler;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public GenericDebugger()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/GB/GBGPUView.cs

@@ -7,11 +7,14 @@ using BizHawk.Common.NumberExtensions;
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Nintendo.Gameboy;
 using BizHawk.Client.EmuHawk.WinFormExtensions;
+using System.Collections.Generic;
 
 namespace BizHawk.Client.EmuHawk
 {
 	public partial class GBGPUView : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		// TODO: freeze semantics are a bit weird: details for a mouseover or freeze are taken from the current
 		// state, not the state at the last callback (and so can be quite different when update is set to manual).
 		// I'm not quite sure what's the best thing to do...

BizHawk.Client.EmuHawk/tools/GB/GBGameGenie.cs

@@ -15,6 +15,8 @@ namespace BizHawk.Client.EmuHawk
 		private readonly Dictionary<char, int> _gameGenieTable = new Dictionary<char, int>();
 		private bool _processing;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		#region Public
 
 		public bool AskSaveChanges() { return true; }

BizHawk.Client.EmuHawk/tools/GBA/GBAGPUView.cs

@@ -6,6 +6,7 @@ using BizHawk.Common.NumberExtensions;
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Nintendo.Gameboy;
 using BizHawk.Emulation.Cores.Nintendo.GBA;
+using System.Collections.Generic;
 
 namespace BizHawk.Client.EmuHawk
 {
@@ -13,6 +14,8 @@ namespace BizHawk.Client.EmuHawk
 	{
 		IGBAGPUViewable gba;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		// emulator memory areas
 		private IntPtr vram;
 		private IntPtr oam;

BizHawk.Client.EmuHawk/tools/Genesis/GenGameGenie.cs

@@ -50,6 +50,8 @@ namespace BizHawk.Client.EmuHawk
 			{ '9', 31 }
 		};
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private bool _processing;
 
 		private void GenGameGenie_Load(object sender, EventArgs e)

BizHawk.Client.EmuHawk/tools/Genesis/VDPViewer.cs

@@ -18,6 +18,8 @@ namespace BizHawk.Client.EmuHawk
 		private GPGX Emu;
 		int palindex = 0;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public GenVDPViewer()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs

@@ -22,6 +22,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class HexEditor : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private bool fontSizeSet = false;
 		private int fontWidth;
 		private int fontHeight;

BizHawk.Client.EmuHawk/tools/IToolForm.cs

@@ -1,7 +1,18 @@
-namespace BizHawk.Client.EmuHawk
+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+namespace BizHawk.Client.EmuHawk
 {
 	public interface IToolForm
 	{
+		/// <summary>
+		/// This should be used to approach any services required of the emulator
+		/// core. It will be populated by ToolManager with the services specified
+		/// in the tool's RequiredServices attribute.
+		/// </summary>
+		IDictionary<Type, object> EmulatorServices { set; }
+
 		/// <summary>
 		/// Will be called by the client anytime an Update needs to occur, such as after an emulated frame, a loadstate, or a related dialog has made a relevant change
 		/// </summary>
@@ -28,7 +39,6 @@
 		/// <returns></returns>
 		bool AskSaveChanges();
 
-
 		/// <summary>
 		/// Indicates whether the tool should be updated before a frame loop or after.
 		/// In general, tools that draw graphics from the core should update before the loop,
@@ -42,4 +52,19 @@
 		void Close();
 		bool IsDisposed { get; }
 	}
+
+	/// <summary>
+	/// Attribute used for IToolForms to indicate which IEmulatorServices they
+	/// need.
+	/// </summary>
+	[AttributeUsage(AttributeTargets.Class, Inherited = false, AllowMultiple = true)]
+	sealed class RequiredServices : Attribute
+	{
+		public readonly Type[] Dependencies;
+
+		public RequiredServices(params Type[] requiredServices)
+		{
+			this.Dependencies = requiredServices;
+		}
+	}
 }

BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs

@@ -19,6 +19,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class LuaConsole : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private readonly LuaFileList _luaList;
 		private int _defaultWidth;
 		private int _defaultHeight;

BizHawk.Client.EmuHawk/tools/NES/BarcodeEntry.cs

@@ -16,6 +16,8 @@ namespace BizHawk.Client.EmuHawk
 	{
 		private DatachBarcode reader;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public BarcodeEntry()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/NES/NESDebugger.cs

@@ -10,6 +10,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class NESDebugger : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private const int ADDR_MAX = 0xFFFF;
 		private const int DISASM_LINE_COUNT = 100;
 		private int defaultWidth;       //For saving the default size of the dialog, so the user can restore if desired

BizHawk.Client.EmuHawk/tools/NES/NESGameGenie.cs

@@ -11,6 +11,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class NESGameGenie : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private readonly Dictionary<char, int> _gameGenieTable = new Dictionary<char, int>
 		{
 			{ 'A', 0 },  // 0000

BizHawk.Client.EmuHawk/tools/NES/NESNameTableViewer.cs

@@ -1,8 +1,8 @@
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.Windows.Forms;
-
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Nintendo.NES;
 
@@ -15,6 +15,8 @@ namespace BizHawk.Client.EmuHawk
 		private readonly NES.PPU.DebugCallback _callback = new NES.PPU.DebugCallback();
 		private NES _nes;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public NESNameTableViewer()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/NES/NESPPU.cs

@@ -6,6 +6,7 @@ using System.Windows.Forms;
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Nintendo.NES;
 using BizHawk.Emulation.Common;
+using System.Collections.Generic;
 
 namespace BizHawk.Client.EmuHawk
 {
@@ -26,6 +27,8 @@ namespace BizHawk.Client.EmuHawk
 		private NES _nes;
 		private bool _forceChange;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public NesPPU()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/PCE/PCEBGViewer.cs

@@ -1,8 +1,8 @@
 using System;
+using System.Collections.Generic;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.Windows.Forms;
-
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.PCEngine;
 
@@ -13,6 +13,8 @@ namespace BizHawk.Client.EmuHawk
 		private PCEngine _pce;
 		private int _vdcType;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public PceBgViewer()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/PCE/PCECDL.cs

@@ -24,6 +24,8 @@ namespace BizHawk.Client.EmuHawk
 		private int _defaultWidth;
 		private int _defaultHeight;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public PCECDL()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/PCE/PCESoundDebugger.cs

@@ -20,6 +20,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class PCESoundDebugger : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public PCESoundDebugger()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/PCE/PCETileViewer.cs

@@ -22,6 +22,8 @@ namespace BizHawk.Client.EmuHawk
 		private int bgpalnum;
 		private int sppalnum;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public PCETileViewer()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/SMS/VDPViewer.cs

@@ -18,6 +18,8 @@ namespace BizHawk.Client.EmuHawk
 		private VDP vdp;
 		int palindex = 0;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public SmsVDPViewer()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/SNES/SNESGameGenie.cs

@@ -38,6 +38,8 @@ namespace BizHawk.Client.EmuHawk
 
 		private bool _processing;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public SNESGameGenie()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/SNES/SNESGraphicsDebugger.cs

@@ -46,6 +46,8 @@ namespace BizHawk.Client.EmuHawk
 		public bool UpdateBefore { get { return false; } }
 		public bool AskSaveChanges() { return true; }
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public void Restart()
 		{
 			if (Global.Emulator is LibsnesCore)

BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.IControlMainForm.cs

@@ -1,7 +1,11 @@
-namespace BizHawk.Client.EmuHawk
+using System;
+using System.Collections.Generic;
+namespace BizHawk.Client.EmuHawk
 {
 	public partial class TAStudio : IControlMainform
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		private bool _suppressAskSave = false;
 
 		public bool WantsToControlReadOnly { get { return false; } }

BizHawk.Client.EmuHawk/tools/TI83/TI83KeyPad.cs

@@ -1,6 +1,6 @@
 using System;
+using System.Collections.Generic;
 using System.Windows.Forms;
-
 using BizHawk.Client.Common;
 using BizHawk.Emulation.Cores.Calculators;
 
@@ -8,6 +8,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class TI83KeyPad : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public TI83KeyPad()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/ToolBox.cs

@@ -19,6 +19,8 @@ namespace BizHawk.Client.EmuHawk
 {
 	public partial class ToolBox : Form, IToolForm
 	{
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public ToolBox()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/ToolManager.cs

@@ -40,6 +40,35 @@ namespace BizHawk.Client.EmuHawk
 			return result;
 		}
 
+		/// <summary>
+		/// Gets all the IEmulatorServices the tool needs, as defined in its
+		/// RequiredServices attribute. If no attribute is defined, returns an
+		/// empty array.
+		/// </summary>
+		public Type[] GetDependencies<T>()
+			where T : IToolForm
+		{
+			var attribute = (RequiredServices)typeof(T)
+				.GetCustomAttributes(typeof(RequiredServices), false)
+				.FirstOrDefault();
+
+			if (attribute == null)
+				return new Type[0];
+			else
+				return attribute.Dependencies;
+		}
+
+		/// <summary>
+		/// Determines whether a tool is available, considering its dependencies
+		/// and the services provided by the emulator core.
+		/// </summary>
+		public bool IsAvailable<T>()
+			where T : IToolForm
+		{
+			return GetDependencies<T>()
+				.All(t => Global.Emulator.ServiceProvider.HasService(typeof(T)));
+		}
+
 		/// <summary>
 		/// Determines whether a given IToolForm is already loaded
 		/// </summary>

BizHawk.Client.EmuHawk/tools/TraceLogger.cs

@@ -26,6 +26,8 @@ namespace BizHawk.Client.EmuHawk
 		private int _defaultWidth;
 		private int _defaultHeight;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public TraceLogger()
 		{
 			InitializeComponent();

BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualpadsTool.cs

@@ -25,6 +25,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
 		
 		public bool Readonly
 		{

BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs

@@ -55,6 +55,8 @@ namespace BizHawk.Client.EmuHawk
 		public const int MaxDetailedSize = 1024 * 1024; // 1mb, semi-arbituary decision, sets the size to check for and automatically switch to fast mode for the user
 		public const int MaxSupportedSize = 1024 * 1024 * 64; // 64mb, semi-arbituary decision, sets the maximum size ram search will support (as it will crash beyond this)
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public bool AskSaveChanges()
 		{
 			return true;

BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs

@@ -39,6 +39,8 @@ namespace BizHawk.Client.EmuHawk
 		private bool _sortReverse;
 		private bool _paused = false;
 
+		public IDictionary<Type, object> EmulatorServices { private get; set; }
+
 		public RamWatch()
 		{
 			_core = (IMemoryDomains)Global.Emulator; // Cast is intentional, better to get a cast exception than a null reference exception later

BizHawk.Emulation.Common/Base Implementations/BasicServiceProvider.cs

@@ -70,17 +70,40 @@ namespace BizHawk.Emulation.Common
 			}
 		}
 
+		public IEmulatorService GetService(Type t)
+		{
+			if (typeof(IEmulatorService).IsAssignableFrom(t))
+			{
+				IEmulatorService service;
+
+				if (Services.TryGetValue(t, out service))
+					return service;
+				else
+					return null;
+			}
+			else
+			{
+				throw new Exception(String.Format("Type {0} does not implement IEmulatorService.", t.Name));
+			}
+		}
+
 		public bool HasService<T>()
 			where T : IEmulatorService
 		{
 			IEmulatorService service;
-			if (Services.TryGetValue(typeof(T), out service))
+			return Services.TryGetValue(typeof(T), out service);
+		}
+
+		public bool HasService(Type t)
+		{
+			if (typeof(IEmulatorService).IsAssignableFrom(t))
 			{
-				return true;
+				IEmulatorService service;
+				return Services.TryGetValue(t, out service);
 			}
 			else
 			{
-				return false;
+				throw new Exception(String.Format("Type {0} does not implement IEmulatorService.", t.Name));
 			}
 		}
 	}

BizHawk.Emulation.Common/Interfaces/IEmulatorServiceProvider.cs

@@ -1,4 +1,5 @@
-namespace BizHawk.Emulation.Common
+using System;
+namespace BizHawk.Emulation.Common
 {
 	public interface IEmulatorServiceProvider
 	{
@@ -6,11 +7,22 @@
 		/// Returns whether or not T is available
 		/// </summary>
 		bool HasService<T>() where T : IEmulatorService;
+		
+		/// <summary>
+		/// Returns whether or not t is available
+		/// </summary>
+		bool HasService(Type t);
 
 		/// <summary>
 		/// Returns an instance of T if T is available
 		/// Else returns null
 		/// </summary>
 		IEmulatorService GetService<T>() where T : IEmulatorService;
+
+		/// <summary>
+		/// Returns an instance of t if t is available
+		/// Else returns null
+		/// </summary>
+		IEmulatorService GetService(Type t);
 	}
 }