/*
	Copyright 2001, 2002 Georges Menie (www.menie.org)
	stdarg version contributed by Christian Ettinger

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU Lesser General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/* Includes */

#include "libSmallPrintf/small_printf.h"

#include <stdarg.h>
#include <stdio.h>
#include <string.h>

/*
	putchar is the only external dependency for this file,
	if you have a working putchar, leave it commented out.
	If not, uncomment the define below and
	replace outbyte(c) by your own function call.
*/
#if defined SERIAL_UART1 || defined SERIAL_UART2 || defined SERIAL_UART3 || defined SERIAL_UART4
extern void PutCharSerial(char c);
#endif

static void printchar(char **str, int c)
{

	if (str)
	{
		**str = c;
		++(*str);
	}
#if defined SERIAL_UART1 || defined SERIAL_UART2 || defined SERIAL_UART3 || defined SERIAL_UART4
	else
		(void)PutCharSerial(c);
#endif
}

char static const PAD_RIGHT = 1;
char static const PAD_ZERO = 2;

static int prints(char **out, const char *string, int width, int pad)
{
	register int pc = 0, padchar = ' ';

	if (width > 0)
	{
		register int len = 0;
		register const char *ptr;
		for (ptr = string; *ptr; ++ptr)
			++len;
		if (len >= width)
			width = 0;
		else
			width -= len;
		if (pad & PAD_ZERO)
			padchar = '0';
	}
	if (!(pad & PAD_RIGHT))
	{
		for (; width > 0; --width)
		{
			printchar(out, padchar);
			++pc;
		}
	}
	for (; *string; ++string)
	{
		printchar(out, *string);
		++pc;
	}
	for (; width > 0; --width)
	{
		printchar(out, padchar);
		++pc;
	}

	return pc;
}

/* the following should be enough for 32 bit int */
#define PRINT_BUF_LEN 12

static int printi(char **out, int i, int b, int sg, int width, int pad, int letbase)
{
	char print_buf[PRINT_BUF_LEN];
	register char *s;
	register int t, neg = 0, pc = 0;
	register unsigned int u = i;

	if (i == 0)
	{
		print_buf[0] = '0';
		print_buf[1] = '\0';
		return prints(out, print_buf, width, pad);
	}

	if (sg && b == 10 && i < 0)
	{
		neg = 1;
		u = -i;
	}

	s = print_buf + PRINT_BUF_LEN - 1;
	*s = '\0';

	while (u)
	{
		t = u % b;
		if (t >= 10)
			t += letbase - '0' - 10;
		*--s = t + '0';
		u /= b;
	}

	if (neg)
	{
		if (width && (pad & PAD_ZERO))
		{
			printchar(out, '-');
			++pc;
			--width;
		}
		else
		{
			*--s = '-';
		}
	}

	return pc + prints(out, s, width, pad);
}

static int small_print(char **out, const char *format, va_list args)
{
	register int width, pad;
	register int pc = 0;
	char scr[2];

	for (; *format != 0; ++format)
	{
		if (*format == '%')
		{
			++format;
			width = pad = 0;
			if (*format == '\0')
				break;
			if (*format == '%')
				goto out;
			if (*format == '-')
			{
				++format;
				pad = PAD_RIGHT;
			}
			while (*format == '0')
			{
				++format;
				pad |= PAD_ZERO;
			}
			if ('*' == *format)
			{
				width = va_arg(args, int); // get width from next argument
				format++;
			}
			else
			{
				for (; *format >= '0' && *format <= '9'; ++format)
				{
					width *= 10;
					width += *format - '0';
				}
			}
			if (*format == 'l')
			{ /* skip l in ld etc */
				format++;
			}
			if (*format == 's')
			{
				register char *s = (char *)va_arg(args, int);
				pc += prints(out, s ? s : "(null)", width, pad);
				continue;
			}
			if (*format == 'd')
			{
				pc += printi(out, va_arg(args, int), 10, 1, width, pad, 'a');
				continue;
			}
			if (*format == 'x')
			{
				pc += printi(out, va_arg(args, int), 16, 0, width, pad, 'a');
				continue;
			}
			if (*format == 'X')
			{
				pc += printi(out, va_arg(args, int), 16, 0, width, pad, 'A');
				continue;
			}
			if (*format == 'u')
			{
				pc += printi(out, va_arg(args, int), 10, 0, width, pad, 'a');
				continue;
			}
			if (*format == 'c')
			{
				/* char are converted to int then pushed on the stack */
				scr[0] = (char)va_arg(args, int);
				scr[1] = '\0';
				pc += prints(out, scr, width, pad);
				continue;
			}
			if (*format == 'n')
			{ /* convert number printed so far and store in *va_arg( args, int)... */
				int *dp = (int *)va_arg(args, int);
				*dp = pc;
				continue;
			}
		}
		else
		{
		out:
			/* deal with LF -> CRLF mapping */
			if (*format == '\n')
			{
				printchar(out, '\r');
				++pc; // extra char
			}
			printchar(out, *format);
			++pc;
		}
	}
	if (out)
		**out = '\0';
	return pc;
}

int small_printf(const char *format, ...)
{
	int result = 0;
	va_list args;

	va_start(args, format);
	result = small_print(0, format, args);
	va_end(args);
	return result;
}

int small_sprintf(char *out, const char *format, ...)
{
	int result = 0;
	va_list args;
	va_start(args, format);
	result = small_print(&out, format, args);
	va_end(args);
	return result;
}