#include <stdint.h>
#include <stddef.h>

#include <print/print.h>

#include "vga.h"

static const size_t VGA_WIDTH = 80;
static const size_t VGA_HEIGHT = 25;
 
static volatile size_t terminal_row;
static volatile size_t terminal_column;
static volatile uint8_t current_color = VGA_WHITE;
static uint16_t *terminal_buffer = (uint16_t*)0xb8000;

void putchar(char c) {
	vga_putc(c);
}

void vga_putc(char c) {
	size_t index = terminal_row*VGA_WIDTH + terminal_column;
	if(c == '\t') {
		vga_putc(' ');
		while(terminal_column % 8 != 0) {
			vga_putc(' ');
		}
		return;
	}
	if(c != '\n' && c != '\t')
		terminal_buffer[index] = (uint16_t)c | (uint16_t)(current_color) << 8;

	if (c == '\n' || ++terminal_column == VGA_WIDTH) {
		terminal_column = 0;
		if (++terminal_row == VGA_HEIGHT)
			terminal_row = 0;
	}
}

void vga_setcolor(uint8_t new_color) {
	current_color = new_color;
}

void vga_write_elsewhere(const char *c, size_t y, size_t x) {
	size_t old_row = terminal_row;
	size_t old_column = terminal_column;
	terminal_row = y;
	terminal_column = x;
	puts(c);
	terminal_row=old_row;
	terminal_column=old_column;
}