From e4841a3886f488cc76489a0f10c167829db07254 Mon Sep 17 00:00:00 2001
From: Adrian Siekierka <kontakt@asie.pl>
Date: Fri, 4 Feb 2022 08:41:51 +0100
Subject: [PATCH] Add reset on START+SELECT, with confirmation

Co-authored-by: DeltaF1 <delyaerricson@gmail.com>
---
 arm9/source/emulator.c | 47 +++++++++++++++++++++++++++++++++++++-----
 arm9/source/uxn.c      | 22 ++++++++++++++++++--
 include/uxn.h          |  1 +
 3 files changed, 63 insertions(+), 7 deletions(-)

diff --git a/arm9/source/emulator.c b/arm9/source/emulator.c
index 8397adf..a22d56a 100644
--- a/arm9/source/emulator.c
+++ b/arm9/source/emulator.c
@@ -28,13 +28,16 @@ static Device *devscreen, *devctrl, *devmouse, *devaudio0;
 
 Uint8 dispswap = 0, debug = 0;
 
-#ifdef DEBUG
 static PrintConsole *mainConsole;
+#ifdef DEBUG
 #ifdef DEBUG_PROFILE
 static PrintConsole profileConsole;
 #endif
 #endif
 
+#define RESET_KEYS (KEY_START | KEY_SELECT)
+#define TICK_RESET_KEYS (KEY_X | KEY_Y)
+
 int
 clamp(int val, int min, int max)
 {
@@ -356,6 +359,37 @@ profiler_ticks(Uint32 tticks, int pos, const char *name)
 }
 #endif
 
+void
+prompt_reset(Uxn *u)
+{
+	consoleClear();
+	iprintf("Would you like to reset uxnds?\n\n [A] - Yes\n [B] - No\n");
+	while(1) {
+		swiWaitForVBlank();
+		scanKeys();
+		int allHeld = keysDown() | keysHeld();
+		if (allHeld & KEY_A) {
+			consoleClear();
+			break;
+		} else if (allHeld & KEY_B) {
+			consoleClear();
+			return;
+		}
+	}
+
+	iprintf("Resetting...\n");
+
+	if(!resetuxn(u))
+		return error("Resetting", "Failed");
+	if(!loaduxn(u, "boot.rom"))
+		return error("Load", "Failed");
+	if(!initppu(&ppu))
+		return error("PPU", "Init failure");
+	evaluxn(u, 0x0100);
+
+	consoleClear();
+}
+
 int
 start(Uxn *u)
 {
@@ -366,12 +400,16 @@ start(Uxn *u)
 	evaluxn(u, 0x0100);
 	while(1) {
 		scanKeys();
+		int allHeld = keysDown() | keysHeld();
 #ifdef DEBUG_PROFILE
 		// X+Y in debugger mode resets tticks_peak
-		if ((keysHeld() & (KEY_X | KEY_Y)) == (KEY_X | KEY_Y))
+		if ((keysDown() & TICK_RESET_KEYS) && ((allHeld & TICK_RESET_KEYS) == TICK_RESET_KEYS))
 			memset(tticks_peak, 0, sizeof(tticks_peak));
 		tticks = timer_ticks(0);
 #endif
+		// On the first frame that L+R are held
+		if ((keysDown() & RESET_KEYS) && ((allHeld & RESET_KEYS) == RESET_KEYS))
+			prompt_reset(u);
 		doctrl(u);
 		domouse(u);
 #ifdef DEBUG_PROFILE
@@ -406,9 +444,8 @@ main(int argc, char **argv)
 	videoSetModeSub(MODE_0_2D);
 	vramSetBankC(VRAM_C_SUB_BG);
 
-#ifdef DEBUG
 	mainConsole = consoleDemoInit();
-
+#ifdef DEBUG
 #ifdef DEBUG_PROFILE
 	// Timers 0-1 - profiling timers
 	TIMER0_DATA = 0;
@@ -423,8 +460,8 @@ main(int argc, char **argv)
 #else
 	consoleSetWindow(mainConsole, 0, 0, 32, 14);
 #endif
-	consoleSelect(mainConsole);
 #endif
+	consoleSelect(mainConsole);
 
 	keyboardDemoInit();
 
diff --git a/arm9/source/uxn.c b/arm9/source/uxn.c
index 72d5d6b..bb980be 100644
--- a/arm9/source/uxn.c
+++ b/arm9/source/uxn.c
@@ -4034,13 +4034,31 @@ evaluxn(Uxn *u, Uint16 vec)
 #endif
 }
 
+int
+resetuxn(Uxn *u)
+{
+	// Reset the stacks
+	memset(&(u->wst), 0, sizeof(Stack));
+	memset(&(u->rst), 0, sizeof(Stack));
+
+	Device *device;
+	for (int i = 0; i < 16; i++) {
+		device = &(u->dev[i]);
+		memset(device->dat, 0, 16);
+		device->vector = (Uint16) 0;
+	}
+
+	// Reset RAM
+	memset(u->ram.dat, 0, 65536);
+	return 1;
+}
+
 int
 bootuxn(Uxn *u)
 {
         memset(u, 0, sizeof(*u));
         u->ram.dat = malloc(65536);
-        memset(u->ram.dat, 0, 65536);
-        return 1;
+	return resetuxn(u);
 }
 
 int
diff --git a/include/uxn.h b/include/uxn.h
index 32a6692..4cdbe8a 100644
--- a/include/uxn.h
+++ b/include/uxn.h
@@ -60,6 +60,7 @@ static inline void   poke16(Uint8 *m, Uint16 a, Uint16 b) { poke8(m, a, b >> 8);
 static inline Uint16 peek16(Uint8 *m, Uint16 a) { return (peek8(m, a) << 8) + peek8(m, a + 1); }
 
 int loaduxn(Uxn *c, char *filepath);
+int resetuxn(Uxn *c);
 int bootuxn(Uxn *c);
 int evaluxn(Uxn *u, Uint16 vec);
 Device *portuxn(Uxn *u, Uint8 id, char *name, int (*talkfn)(Device *, Uint8, Uint8));