/** 
 * Copyright (c) 2016 rxi
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the MIT license. See LICENSE for details.
 */

#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <dos.h>
#include <sys/movedata.h>

#include "vga.h"

int vga_inited = 0;


void vga_init(void) {
  if (vga_inited) return;
  vga_inited = 1;
  union REGS regs = {};
  regs.h.al = 0x13;
  int86(0x10, &regs, &regs);
}


void vga_deinit(void) {
  if (!vga_inited) return;
  vga_inited = 0;
  union REGS regs = {};
  regs.h.al = 0x3;
  int86(0x10, &regs, &regs);
}


void vga_update(pixel_t *buffer) {
  dosmemput(buffer, VGA_WIDTH * VGA_HEIGHT, 0xa0000);
}