//kio.c
// Author: Josh Holtrop
// Created: 12/25/03
// Modified: 12/25/03


// This is the main output routine, it uses a format string and a variable
//  number of arguments to print formatted text
void	printf(char *fmt, ...)
{
	dword *params = ((dword *)(&fmt)) + 1;		//points to the first paramater
	int i;
	int special = 0;
	for (i = 0; ; i++)
	{
		if (special)
		{
			special = 0;
			switch (fmt[i])
			{
			case 0:
				return;
			case '%':
				putc('%');
				break;
			case 's': case 'S':
				puts((char *)*params);
				params++;
				break;
			case 'c': case 'C':
				putc(*params);
				params++;
				break;
			case 'd': case 'D':
				putDec(*params);
				params++;
				break;
			case 'u': case 'U':
				putDecu(*params);
				params++;
				break;
			case 'x': case 'X':
				putHex(*params);
				params++;
				break;
			}
		}
		else
		{
			switch (fmt[i])
			{
			case '%':
				special = 1;
				break;
			case 0:
				return;
			default:
				putc(fmt[i]);
			}
		}
	}
}


// This function draws a single character
void	putc(dword chr)
{
 	char charac = (char)chr;
	word *vidmem = (word *)0xC00B8000;
	if (charac == '\n')
	{
		if (cursorPosition % 80)
			cursorPosition = cursorPosition + 80 - (cursorPosition % 80);
		else
			cursorPosition += 80;
	}
	else if (charac == '\t')
	{
		if (cursorPosition % 8)
			cursorPosition = cursorPosition + 8 - (cursorPosition % 8);
		else
			cursorPosition += 8;
	}
	else
	{
		if (videoMode)
		{
			console_memory[cursorPosition] = charac | 0x0700;
			video_drawConsoleChar(cursorPosition);
		}
		else
		{
			console_memory[cursorPosition] = charac | 0x0700;
			vidmem[cursorPosition] = charac | 0x0700;
		}
		cursorPosition++;
	}
	if (cursorPosition >= 2000)
	{
		console_scroll();
		cursorPosition = 2000-80;
		if (videoMode)
			video_drawConsole();
	}
	if (!videoMode)
		writeCursorPosition(cursorPosition);
}


// This function displays a number in hexadecimal
int putHex(dword number)
{
	int hitNum = 0;
	int i;
	for (i = 7; i >= 0; i--)
	{
		dword val = (number >> (i*4)) & 0xF;
		if ((val != 0) || (i == 0))
			hitNum = 1;
		if (hitNum)
		{
			val = val + '0';
			if (val > '9')
				val = val + ('A' - '9' - 1);
			putc(val);
		}
	}
}