#include <stdbool.h>
#include <stdint.h>

#define VGA_COM_MIRROR

#ifdef VGA_COM_MIRROR
#include "serial.h"
#endif

#define VGA_COLUMNS 80
#define VGA_LINES 25
#define VGA_START (uint16_t *)0x000b8000
#define VGA_END (VGA_START + VGA_COLUMNS * VGA_LINES)
uint16_t *cursor = VGA_START;
uint16_t color = 0x1f00;

void vga_set_color(uint8_t new_color) {
  color = new_color << 8;
}

void vga_scroll() {
  cursor = VGA_START;
}

void vga_blank() {
#ifdef VGA_COM_MIRROR
  soutsz("\r\n\r\n<CLEAR>\r\n\r\n");
#endif
  uint32_t f = (color << 16) | color | 0x00200020;
  uint32_t *p = (uint32_t *)VGA_START;
  while (p < (uint32_t *)VGA_END)
    *(p++) = f;
  cursor = VGA_START;
}

void vga_printch(char ch) {
  if (ch == '\n') {
#ifdef VGA_COM_MIRROR
    soutsz("\r\n");
#endif
    if ((cursor = cursor - (cursor - VGA_START) % VGA_COLUMNS + VGA_COLUMNS) == VGA_END)
      vga_scroll();
    return;
  }
#ifdef VGA_COM_MIRROR
  sout(ch);
#endif
  *(cursor++) = color | (uint8_t)ch;
  if (cursor == VGA_END)
    vga_scroll();
}

void vga_printsz(const char *sz) {
  while (*sz)
    vga_printch(*(sz++));
}

void vga_printsn(const char *sn, uint8_t n) {
  while (n--)
    vga_printch(*(sn++));
}