From 7bc9bf9d9f460d233dced7145401c78a91e4126c Mon Sep 17 00:00:00 2001
From: Luxdragon <kopse@e.email>
Date: Sat, 13 Jan 2024 22:38:02 +0100
Subject: [PATCH] First experimentation with GTK

---
 emulator_shell.c | 123 +++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 107 insertions(+), 16 deletions(-)

diff --git a/emulator_shell.c b/emulator_shell.c
index 08c90e9..22c2971 100644
--- a/emulator_shell.c
+++ b/emulator_shell.c
@@ -2,9 +2,43 @@
 #include <stdlib.h>
 #include <stdint.h> // for the uintx_t's
 #include <unistd.h> // for sleep
-#include <string.h> // for memset
+#include <gtk/gtk.h>
 
-// gcc emulator_shell.c -o emulator
+// gcc emulator_shell.c `pkg-config --cflags --libs gtk+-3.0` -o emulator
+
+static gboolean on_key_press(GtkWidget *widget, GdkEventKey *event, gpointer user_data)
+{
+    switch (event->keyval)
+    {
+        case GDK_KEY_Left:
+            // Code to be executed when the left arrow key is pressed down
+            g_print("Left arrow key pressed down\n");
+            break;
+        case GDK_KEY_Right:
+            // Code to be executed when the right arrow key is pressed down
+            g_print("Right arrow key pressed down\n");
+            break;
+    }
+
+    return FALSE;
+}
+
+static gboolean on_key_release(GtkWidget *widget, GdkEventKey *event, gpointer user_data)
+{
+    switch (event->keyval)
+    {
+        case GDK_KEY_Left:
+            // Code to be executed when the left arrow key is released
+            g_print("Left arrow key released\n");
+            break;
+        case GDK_KEY_Right:
+            // Code to be executed when the right arrow key is released
+            g_print("Right arrow key released\n");
+            break;
+    }
+
+    return FALSE;
+}
 
 int disassemble8080(unsigned char* code) {
     int opbytes = 1;
@@ -331,7 +365,10 @@ typedef struct State8080 {
     uint16_t    pc;    
     uint8_t     *memory;    
     ConditionCodes      cc;    
-    uint8_t     int_enable;    
+    uint8_t     int_enable;  
+    uint8_t shift_offset;
+    uint8_t shift0;
+    uint8_t shift1;  
 } State8080;
 
 void unknownInstruction(State8080* state) {
@@ -352,6 +389,14 @@ int parity(int x, int size)
 	return (0 == (p & 0x1));
 }
 
+void printState(State8080* state) {
+    printf("\tC=%d,P=%d,S=%d,Z=%d\n", state->cc.cy, state->cc.p,    
+        state->cc.s, state->cc.z);    
+    printf("\tA $%02x B $%02x C $%02x D $%02x E $%02x H $%02x L $%02x SP %04x\n",    
+        state->a, state->b, state->c, state->d,    
+        state->e, state->h, state->l, state->sp); 
+}
+
 int emulate8080(State8080* state) {
     unsigned char *opcode = &(state->memory[state->pc]);
 
@@ -651,7 +696,7 @@ int emulate8080(State8080* state) {
             state->sp += 2;
             break;
         case 0xd3:              // OUT byte
-            printf("%c", opcode[1]);
+            //printf("%c", opcode[1]);
             state->pc++;
             break;
         case 0xd5:              // PUSH D
@@ -659,7 +704,10 @@ int emulate8080(State8080* state) {
             state->memory[state->sp-2] = state->e;
             state->sp -= 2;
             break;
-        
+        case 0xdb:              // IN byte
+            //printf("%c", opcode[1]);
+            state->pc++;
+            break;
         case 0xe1:              // POP H
             state->l = state->memory[state->sp];
             state->h = state->memory[state->sp+1];
@@ -732,11 +780,7 @@ int emulate8080(State8080* state) {
 
         default: unknownInstruction(state); break;
     }
-    printf("\tC=%d,P=%d,S=%d,Z=%d\n", state->cc.cy, state->cc.p,    
-        state->cc.s, state->cc.z);    
-    printf("\tA $%02x B $%02x C $%02x D $%02x E $%02x H $%02x L $%02x SP %04x\n",    
-        state->a, state->b, state->c, state->d,    
-        state->e, state->h, state->l, state->sp); 
+    printState(state);
     
 }
 
@@ -756,15 +800,50 @@ void read_Space_Invaders_ROM(State8080* state, const char* filename, int offset)
 
     fread(buffer, fsize, 1, file);    
     fclose(file);    
-
 }
 
-int main (void)  {
+uint8_t machineIn(State8080* state, uint8_t port) {
+    uint8_t a;
+    switch(port) {
+        case 3:
+        {
+            uint16_t v = (state->shift1<<8) | (state->shift0);
+            a = ((v >> (8-state->shift_offset)) & 0xff);
+        }
+        break;
+    }
+    return a;
+}
+
+uint8_t machineOut(State8080* state, uint8_t port, uint8_t value) {
+    uint8_t a;
+    switch(port) {
+        case 2:
+        {
+            state->shift_offset = value & 0x7;
+        } break;
+        case 4:
+        {   
+            state->shift0 = state->shift1;
+            state->shift1 = value;
+            break;
+        }
+    }
+}
+
+int main (int argc, char *argv[])  {
+    gtk_init(&argc, &argv);
+    GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+    g_print("Test\n");
+    g_signal_connect(window, "key-press-event", G_CALLBACK(on_key_press), NULL);
+    g_signal_connect(window, "key-release-event", G_CALLBACK(on_key_release), NULL);
+    gtk_widget_show(window);
+    
 
     //Initializations
 
-    State8080 *state = (State8080*) malloc(sizeof(State8080));
-    memset(state, 0, sizeof(State8080));
+    State8080 *state = (State8080*) calloc(1, sizeof(State8080));
+    //memset(state, 0, sizeof(State8080));
     state->cc.z = 1;
     state->cc.s = 1;
     state->cc.p = 1;
@@ -779,14 +858,26 @@ int main (void)  {
     read_Space_Invaders_ROM(state, "ROM/invaders.e", 0x1800);
 
     int i = 0;
+    char done = 0;
 
-    while (1) {
-        //Show the command in the code
+    while (!done) {
+        uint8_t* opcode = &state->memory[state->pc];
         printf("%d\t\t:", i);
+
+        if (*opcode == 0xdb) {
+            uint8_t port = opcode[1];
+            state->a = machineIn(state, port);
+            state->pc++;
+        } else if (*opcode == 0xd3) {
+            uint8_t port = opcode[1];
+            machineOut(state, port, 0x00);
+            state->pc++;
+        }
         emulate8080(state);
         i++;
         sleep(0.00001);
     }
+    gtk_main();
     free(state->memory);
     free(state);
     return 0;