refactor(main): implement src/main.c platform frontend

src/main.c

@@ -0,0 +1,198 @@
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <signal.h>
+#include <string.h>
+#include <math.h>
+#include <raylib.h>
+#include "chip8.h"
+
+#define CPU_CLOCK_HZ 600
+#define TIMER_HZ 60
+
+const int CYCLES_PER_FRAME = CPU_CLOCK_HZ / TIMER_HZ;
+
+volatile sig_atomic_t keep_running = 1;
+
+void handle_sigint(int sig) {
+  (void)sig;
+  keep_running = 0;
+}
+
+void println(const char *format, ...) {
+  va_list args;
+  va_start(args, format);
+  vprintf(format, args);
+  va_end(args);
+  printf("\n");
+}
+
+void setup_graceful_exit() {
+  signal(SIGINT, handle_sigint);
+  signal(SIGTERM, handle_sigint);
+}
+
+void update_keys(chip_eight_t *chip) {
+  chip->keys[1] = IsKeyDown(KEY_ONE);
+  chip->keys[2] = IsKeyDown(KEY_TWO);
+  chip->keys[3] = IsKeyDown(KEY_THREE);
+  chip->keys[12] = IsKeyDown(KEY_FOUR);
+
+  chip->keys[4] = IsKeyDown(KEY_Q);
+  chip->keys[5] = IsKeyDown(KEY_W);
+  chip->keys[6] = IsKeyDown(KEY_E);
+  chip->keys[13] = IsKeyDown(KEY_R);
+
+  chip->keys[7] = IsKeyDown(KEY_A);
+  chip->keys[8] = IsKeyDown(KEY_S);
+  chip->keys[9] = IsKeyDown(KEY_D);
+  chip->keys[14] = IsKeyDown(KEY_F);
+
+  chip->keys[10] = IsKeyDown(KEY_Z);
+  chip->keys[0] = IsKeyDown(KEY_X);
+  chip->keys[11] = IsKeyDown(KEY_C);
+  chip->keys[15] = IsKeyDown(KEY_V);
+}
+
+int main(int argc, char *argv[]) {
+  setup_graceful_exit();
+
+  if (argc < 2) {
+    println("You fucked up bro! We need a file to load into memory.");
+    println("Usage: chip.exe <file-to-load>");
+    return FILE_NOT_PROVIDED;
+  }
+
+  chip_eight_t *chip = malloc(sizeof(chip_eight_t));
+
+  if (chip == NULL) {
+    println("Failed to allocate memory for chip.");
+    return MEMORY_ALLOCATION_FAILURE;
+  }
+
+  chip8_init(chip);
+
+  int load_rom_result = chip8_load_rom(chip, argv[1]);
+
+  if (load_rom_result != COMPLETED_SUCCESSFULLY) {
+    if (load_rom_result == FILE_MISSING) {
+      println("Error: The file '%s' could not be found or opened.", argv[1]);
+    } else if (load_rom_result == PROGRAM_TOO_LARGE) {
+      println("Error: The program is too large to fit in CHIP-8 memory.");
+    } else {
+      println("Error: Failed to load ROM (code %d).", load_rom_result);
+    }
+    free(chip);
+    return load_rom_result;
+  }
+
+  // Setup audio
+  InitAudioDevice();
+
+  // Generate 440Hz Sine wave beep in memory
+  int sampleRate = 44100;
+  float durationSeconds = 0.1f;
+  int frameCount = sampleRate * durationSeconds;
+  float *data = (float *)malloc(frameCount * sizeof(float));
+  if (data != NULL) {
+    for (int i = 0; i < frameCount; i++) {
+      data[i] = sinf(2.0f * PI * 440.0f * ((float)i / sampleRate)) * 0.2f;
+    }
+  }
+  Wave wave = { 0 };
+  wave.frameCount = frameCount;
+  wave.sampleRate = sampleRate;
+  wave.sampleSize = 32;
+  wave.channels = 1;
+  wave.data = data;
+
+  Sound beep_sound = LoadSoundFromWave(wave);
+  UnloadWave(wave); // Frees the 'data' buffer in system RAM
+
+  int scale_factor = 10;
+  int display_width = SCREEN_WIDTH * scale_factor;
+  int display_height = SCREEN_HEIGHT * scale_factor;
+  InitWindow(display_width, display_height, "chip");
+  SetTargetFPS(60);
+
+  while(!WindowShouldClose() && keep_running)
+  {
+    update_keys(chip);
+
+    if (chip->waiting_for_key) {
+      bool key_pressed = false;
+
+      for (int i = 0; i < 16; i++) {
+        if (chip->keys[i]) {
+          chip->V[chip->key_register] = i;
+          chip->waiting_for_key = false;
+          key_pressed = true;
+          break;
+        }
+      }
+
+      if (!key_pressed) {
+        BeginDrawing();
+        ClearBackground(BLACK);
+
+        for (int i = 0; i < SCREEN_HEIGHT; i++) {
+          for (int j = 0; j < SCREEN_WIDTH; j++) {
+            uint32_t screen_pixel = chip->display[i * SCREEN_WIDTH + j];
+
+            if (screen_pixel == 1) {
+              DrawRectangle(j * scale_factor, i * scale_factor, scale_factor, scale_factor, RAYWHITE);
+            }
+          }
+        }
+
+        EndDrawing();
+        continue;
+      }
+    }
+
+    for(int i = 0; i < CYCLES_PER_FRAME; i++) {
+      if (chip->waiting_for_key) {
+        break;
+      }
+      chip8_step(chip);
+    }
+
+    bool play_beep = (chip->st > 0);
+    chip8_tick_timers(chip);
+
+    if (play_beep) {
+      if (!IsSoundPlaying(beep_sound)) {
+        PlaySound(beep_sound);
+      }
+    } else {
+      if (IsSoundPlaying(beep_sound)) {
+        StopSound(beep_sound);
+      }
+    }
+
+    BeginDrawing();
+    ClearBackground(BLACK);
+
+    for (int i = 0; i < SCREEN_HEIGHT; i++) {
+      for (int j = 0; j < SCREEN_WIDTH; j++) {
+        uint32_t screen_pixel = chip->display[i * SCREEN_WIDTH + j];
+
+        if (screen_pixel == 1) {
+          DrawRectangle(j * scale_factor, i * scale_factor, scale_factor, scale_factor, RAYWHITE);
+        }
+      }
+    }
+
+    EndDrawing();
+  }
+
+  free(chip);
+
+  UnloadSound(beep_sound);
+  CloseAudioDevice();
+
+  CloseWindow();
+
+  return COMPLETED_SUCCESSFULLY;
+}