#include "../../vm/vm.h"
#include "../../vm/device.h"
#include "devices.h"
#include <SDL2/SDL.h>
#include <emscripten.h>
#include <emscripten/html5.h>
#include <stdio.h>

VM vm = {0};

static DeviceOps screen_ops = {.open = screen_open,
                               .read = screen_read,
                               .write = screen_write,
                               .close = screen_close,
                               .ioctl = screen_ioctl};

static DeviceOps mouse_ops = {.open = mouse_open,
                              .read = mouse_read,
                              .write = mouse_write,
                              .close = mouse_close,
                              .ioctl = nil};

static DeviceOps console_device_ops = {
    .open = console_open,
    .read = console_read,
    .write = console_write,
    .close = console_close,
    .ioctl = console_ioctl,
};

static ScreenDeviceData screen_data = {0};
static MouseDeviceData mouse_data = {0};

void mainloop() {
  if (!step_vm(&vm)) {
    emscripten_cancel_main_loop();
    printf("VM execution completed\n");
  }
}

bool loadVM(const char *filename, VM *vm) {
  FILE *file = fopen(filename, "rb");
  if (!file) {
    printf("Failed to open ROM file: %s\n", filename);
    return false;
  }

  // Read VM state
  if (fread(&vm->pc, sizeof(u32), 1, file) != 1 ||
      fread(&vm->cp, sizeof(u32), 1, file) != 1 ||
      fread(&vm->fp, sizeof(u32), 1, file) != 1 ||
      fread(&vm->sp, sizeof(u32), 1, file) != 1 ||
      fread(&vm->rp, sizeof(u32), 1, file) != 1 ||
      fread(&vm->mp, sizeof(u32), 1, file) != 1 ||
      fread(&vm->dc, sizeof(u32), 1, file) != 1 ||
      fread(&vm->flag, sizeof(i32), 1, file) != 1) {
    printf("Failed to read VM state\n");
    fclose(file);
    return false;
  }

  // Read code section
  if (fread(vm->code, 1, vm->cp, file) != vm->cp) {
    printf("Failed to read code section\n");
    fclose(file);
    return false;
  }

  // Read memory section
  if (fread(vm->memory, 1, vm->mp, file) != vm->mp) {
    printf("Failed to read memory section\n");
    fclose(file);
    return false;
  }

  fclose(file);
  return true;
}

int main(int argc, char **argv) {
  if (SDL_Init(SDL_INIT_VIDEO) < 0) {
    printf("SDL initialization failed: %s\n", SDL_GetError());
    return 1;
  }
  SDL_SetHint(SDL_HINT_TOUCH_MOUSE_EVENTS, "0");

  #ifdef __EMSCRIPTEN__
  emscripten_set_canvas_element_size("#canvas", 640, 480);
  #endif

  loadVM("paint.rom", &vm);
  printf("VM loaded successfully\n");
  
  // Initialize device data
  screen_data.width = 640;
  screen_data.height = 480;
  screen_data.size = 640 * 480;
  screen_data.window = NULL;
  screen_data.renderer = NULL;
  screen_data.texture = NULL;

  mouse_data.x = 0;
  mouse_data.y = 0;
  mouse_data.btn1 = 0;
  mouse_data.btn2 = 0;
  mouse_data.btn3 = 0;
  mouse_data.btn4 = 0;
  mouse_data.size = 12;

  // Register devices
  vm_register_device(&vm, "/dev/screen/0", "screen", &screen_data, &screen_ops);
  vm_register_device(&vm, "/dev/mouse/0", "mouse", &mouse_data, &mouse_ops);
  vm_register_device(&vm, "/dev/term/0", "terminal", NULL, &console_device_ops);

  // Set up main loop
  emscripten_set_main_loop(mainloop, 0, 1);
  return 0;
}