From 264436e6140fb40d6416cb16efceea5b2a268713 Mon Sep 17 00:00:00 2001
From: nattthebear <goyuken@gmail.com>
Date: Sun, 2 Jul 2017 16:15:54 -0400
Subject: [PATCH] PicoDrive:  input plus lagged and callback

---
 .../Consoles/Sega/PicoDrive/LibPicoDrive.cs   |  7 +++++
 .../Consoles/Sega/PicoDrive/PicoDrive.cs      | 29 ++++++++++++++++++-
 waterbox/picodrive/bizhawk.c                  | 11 +++++++
 waterbox/picodrive/pico/memory.c              | 20 ++++++++-----
 waterbox/picodrive/pico/pico.h                |  3 ++
 5 files changed, 62 insertions(+), 8 deletions(-)

diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/LibPicoDrive.cs b/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/LibPicoDrive.cs
index 0d7e44e51e..43c153f1ab 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/LibPicoDrive.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/LibPicoDrive.cs
@@ -3,6 +3,7 @@ using BizHawk.Emulation.Cores.Waterbox;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -10,6 +11,12 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.PicoDrive
 {
 	public abstract class LibPicoDrive : LibWaterboxCore
 	{
+		[StructLayout(LayoutKind.Sequential)]
+		public new class FrameInfo : LibWaterboxCore.FrameInfo
+		{
+			public int Buttons;
+		}
+
 		[BizImport(CC)]
 		public abstract bool Init();
 	}
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/PicoDrive.cs b/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/PicoDrive.cs
index e5792d474e..2bf854b7cb 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/PicoDrive.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/PicoDrive.cs
@@ -41,11 +41,38 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.PicoDrive
 				throw new InvalidOperationException("Core rejected the rom!");
 			_exe.RemoveReadonlyFile("romfile.md");
 			PostInit();
+			ControllerDefinition = PicoDriveController;
 		}
 
+		public static readonly ControllerDefinition PicoDriveController = new ControllerDefinition
+		{
+			Name = "PicoDrive Genesis Controller",
+			BoolButtons =
+			{
+				"P1 Up", "P1 Down", "P1 Left", "P1 Right", "P1 A", "P1 B", "P1 C", "P1 Start", "P1 X", "P1 Y", "P1 Z", "P1 Mode",
+				"P2 Up", "P2 Down", "P2 Left", "P2 Right", "P2 A", "P2 B", "P2 C", "P2 Start", "P2 X", "P2 Y", "P2 Z", "P2 Mode",
+				"Power", "Reset"
+			}
+		};
+
+		private static readonly string[] ButtonOrders =
+		{
+			"P1 Up", "P1 Down", "P1 Left", "P1 Right", "P1 B", "P1 C", "P1 A", "P1 Start", "P1 Z", "P1 Y", "P1 X", "P1 Mode",
+			"P2 Up", "P2 Down", "P2 Left", "P2 Right", "P2 B", "P2 C", "P2 A", "P2 Start", "P2 Z", "P2 Y", "P2 X", "P2 Mode",
+			"Power", "Reset"
+		};
+
 		protected override LibWaterboxCore.FrameInfo FrameAdvancePrep(IController controller, bool render, bool rendersound)
 		{
-			return new LibWaterboxCore.FrameInfo();
+			var b = 0;
+			var v = 1;
+			foreach (var s in ButtonOrders)
+			{
+				if (controller.IsPressed(s))
+					b |= v;
+				v <<= 1;
+			}
+			return new LibPicoDrive.FrameInfo { Buttons = b };
 		}
 	}
 }
diff --git a/waterbox/picodrive/bizhawk.c b/waterbox/picodrive/bizhawk.c
index 41c8d18389..ae697886d3 100644
--- a/waterbox/picodrive/bizhawk.c
+++ b/waterbox/picodrive/bizhawk.c
@@ -64,6 +64,7 @@ int pm_close(pm_file *fp)
 typedef struct
 {
 	FrameInfo b;
+	uint32_t Buttons;
 } MyFrameInfo;
 
 static int video_start_line;
@@ -147,8 +148,17 @@ static void Blit(void)
 ECL_EXPORT void FrameAdvance(MyFrameInfo *f)
 {
 	current_frame = f;
+	PicoInputWasRead = 0;
+	PicoPad[0] = f->Buttons & 0xfff;
+	PicoPad[1] = f->Buttons >> 12 & 0xfff;
+	if (f->Buttons & 0x1000000)
+		PicoPower();
+	if (f->Buttons & 0x2000000)
+		PicoReset();
+
 	PicoFrame();
 	Blit();
+	f->b.Lagged = !PicoInputWasRead;
 	current_frame = NULL;
 }
 
@@ -163,6 +173,7 @@ ECL_EXPORT void GetMemoryAreas(MemoryArea *m)
 
 ECL_EXPORT void SetInputCallback(void (*callback)(void))
 {
+	PicoInputCallback = callback;
 }
 
 int main(void)
diff --git a/waterbox/picodrive/pico/memory.c b/waterbox/picodrive/pico/memory.c
index 4f38e5e2a3..f64b3a23a6 100644
--- a/waterbox/picodrive/pico/memory.c
+++ b/waterbox/picodrive/pico/memory.c
@@ -241,18 +241,24 @@ static port_read_func *port_readers[3] = {
   read_nothing
 };
 
+void (*PicoInputCallback)(void);
+int PicoInputWasRead;
+
 static NOINLINE u32 port_read(int i)
 {
-  u32 data_reg = Pico.ioports[i + 1];
-  u32 ctrl_reg = Pico.ioports[i + 4] | 0x80;
-  u32 in, out;
+	PicoInputWasRead = 1;
+	if (PicoInputCallback)
+		PicoInputCallback();
+	u32 data_reg = Pico.ioports[i + 1];
+	u32 ctrl_reg = Pico.ioports[i + 4] | 0x80;
+	u32 in, out;
 
-  out = data_reg & ctrl_reg;
-  out |= 0x7f & ~ctrl_reg; // pull-ups
+	out = data_reg & ctrl_reg;
+	out |= 0x7f & ~ctrl_reg; // pull-ups
 
-  in = port_readers[i](i, out);
+	in = port_readers[i](i, out);
 
-  return (in & ~ctrl_reg) | (data_reg & ctrl_reg);
+	return (in & ~ctrl_reg) | (data_reg & ctrl_reg);
 }
 
 void PicoSetInputDevice(int port, enum input_device device)
diff --git a/waterbox/picodrive/pico/pico.h b/waterbox/picodrive/pico/pico.h
index 9a4e2b8f70..b15f67672e 100644
--- a/waterbox/picodrive/pico/pico.h
+++ b/waterbox/picodrive/pico/pico.h
@@ -84,6 +84,9 @@ typedef enum { PI_ROM, PI_ISPAL, PI_IS40_CELL, PI_IS240_LINES } pint_t;
 typedef union { int vint; void *vptr; } pint_ret_t;
 void PicoGetInternal(pint_t which, pint_ret_t *ret);
 
+extern void (*PicoInputCallback)(void);
+extern int PicoInputWasRead;
+
 // cd/mcd.c
 extern void (*PicoMCDopenTray)(void);
 extern void (*PicoMCDcloseTray)(void);