// kio.c
// Author: Josh Holtrop
// Created: 12/25/03
// Modified: 04/06/04

#include "hos_defines.h"
#include "kio.h"
#include "asmfuncs.h"
#include "video/video.h"

dword	cursorPosition;			//Caches the current cursor position
word	console_memory[2000];		//holds a copy of the console's memory

// This is the main output routine, it uses a format string and a variable
//  number of arguments to print formatted text
extern "C" {

void	kio_init()
{
	cursorPosition = 0;
	writeCursorPosition(0);
	word *vidmem = (word *)0xC00B8000;
	for (int i = 0; i < 2000; i++)
	{
		console_memory[i] = 0x0720;
		vidmem[i] = 0x0720;
	}
}

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': case 'i': case 'I':
				putDec(*params);
				params++;
				break;
			case 'u': case 'U':
				putDecu(*params);
				params++;
				break;
			case 'x': case 'X':
				putHex(*params);
				params++;
				break;
			case 'b': case 'B':
				kio_putBCD(*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 (video_Mode())
		{
			console_memory[cursorPosition] = charac | 0x0700;
			kio_drawConsoleChar(cursorPosition);
		}
		else
		{
			console_memory[cursorPosition] = charac | 0x0700;
			vidmem[cursorPosition] = charac | 0x0700;
		}
		cursorPosition++;
	}
	if (cursorPosition >= 2000)
	{
		kio_console_scroll();
		cursorPosition = 2000-80;
	}
	if (!video_Mode())
		writeCursorPosition(cursorPosition);
}


// This function displays a number in hexadecimal
void	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);
		}
	}
}


void	kio_putBCD(dword bcd)
{
	putc(((bcd & 0xF0) >> 4) + '0');
	putc((bcd & 0xF) + '0');
}


void	kio_console_scroll()
{
	memcpyd(console_memory, console_memory + 80, 960);
	memsetw(console_memory + 1920, 0x0720, 80);
	if (video_Mode())
		kio_drawConsole();
	else
		memcpyd((void *)0xC00B8000, console_memory, 1000);
}


void	kio_console_cls()
{
	memsetw(console_memory, 0x0720, 2000);
	if (video_Mode())
		kio_drawConsole();
	else
		memcpyd((void *)0xC00B8000, console_memory, 1000);
	writeCursorPosition(0);
}


// This function draws a simple "console" window in graphical mode to display text
void	kio_drawConsole()
{
	video_rectf(8, 8, 491, 261, 0);
	video_rect(7, 7, 492, 262, 0x00777777);
	int x, y;
	x = 250, y = 135;
	int s = 100, p = 0;
	for (p = 0; p <= s; p += 16)
	{
		video_line(x + p, y, x, y + s - p, 0x00008800);
		video_line(x + p, y, x, y - s + p, 0x00008800);
		video_line(x - p, y, x, y + s - p, 0x00008800);
		video_line(x - p, y, x, y - s + p, 0x00008800);
	}
	
	for (x = 0; x < 80; x++)
	{
		for (y = 0; y < 25; y++)
		{
			video_renderChar(x*6+10, y*10+10, console_memory[y*80+x], 0, 0x00FFFFFF, 0, 0);
		}
	}
}


// This function draws a "console" character to the graphical video screen
void	kio_drawConsoleChar(dword position)
{
 	int x = position % 80;
 	int y = position / 80;
	video_renderChar(x*6+10, y*10+10, console_memory[y*80+x], 0, 0x00FFFFFF, 1, 0);
}


dword	kio_getCursorPosition()
{
	return cursorPosition;
}

void	kio_writeCursorPosition(dword position)
{
	cursorPosition = position;
	writeCursorPosition(position);
}


}