/******************************************************************
*           LibC for the LittleFox' Operating System              *
*                  Copyright (c) 2010 LittleFox                   *
*                  http://littlefox.web-fuxx.de/                  *
*******************************************************************
*              based on the API of LF OS 1.0 Alpha 4              *
******************************************************************/

#include "sdk/stdio.h"

int printf_res;
int inputCount = 0;

int getch()
{
	int c;
	__asm__ __volatile__ ("int $0x30": "=b"(c):"a"(3));
	if(c >= 0x20 && c <= 0x7E)
		inputCount++;
	return c;
}

char keyBuffer[2048] = "";

void putc(char c)
{
	printf_res++;
	__asm __volatile__ ("int $0x30":: "a" (0), "b" (c));
}

void puts(const char* s)
{
	while (*s)
	{
		putc(*s++);
	}
}

void putn(unsigned long x, int base)
{
	char buf[65];
	const char* digits = "0123456789abcdefghijklmnopqrstuvwxyz";
	char* p;
	if (base > 36)
	{
		return;
	}
	p = buf + 64;
	*p = '\0';
	do
	{
		*--p = digits[x % base];
		x /= base;
	} while (x);
	puts(p);
}

int printf(const char* fmt, ...)
{
	va_list ap;
	const char* s;
	unsigned long n;
	va_start(ap, fmt);
	int printf_res = 0;
	int c;
	inputCount = 0;
	while (*fmt)
	{
		if (*fmt == '%')
		{
			fmt++;
			
			switch (*fmt)
			{
				case 's':
					s = va_arg(ap, char*);
					puts(s);
					break;
				case 'd':
				case 'u':
					n = va_arg(ap, unsigned long int);
					putn(n, 10);
					break;
				case 'x':
				case 'p':
					n = va_arg(ap, unsigned long int);
					putn(n, 16);
					break;
				case '%':
					putc('%');
					break;
				case 'c':
					c = va_arg(ap, int);
					putc(c);
					break;
				case '\0':
					goto out;
				default:
					putc('%');
					putc(*fmt);
					break;
			}
		}
		else
		{
			putc(*fmt);
		}
		fmt++;
	}
	out:
		va_end(ap);
	return printf_res;
}

char *getline()
{
	int i;
	for(i = 0; i < 2048; i++)
	{
		keyBuffer[i] = 0;
	}
	int t = getch();
	i = 0;
	while(t != '\n')
	{
		if(t != 0 && t != '\b')
		{
			keyBuffer[i] = t;
			i++;
			putc(t);
		}
		if(t == '\b' && inputCount > 0)
		{
			i--;
			keyBuffer[i] = 0;
			asm("int $0x30"::"a"(5), "b"(-1), "d"(1));
			putc(' ');
			asm("int $0x30"::"a"(5), "b"(-1), "d"(1));
			inputCount--;
		}
		t = getch();
	}
	inputCount = 0;
	return keyBuffer;
}

void clear_screen()
{
	__asm__ __volatile__ ("int $0x30"::"a"(1));
}

void set_color(int color)
{
	__asm__ __volatile__ ("int $0x30"::"a"(2), "b"(color));
}