/*
 * Copyright (C) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <putchar.h>
#include <print.h>
#include <synch/spinlock.h>
#include <arch/arg.h>
#include <arch/asm.h>
#include <arch/fmath.h>

#include <arch.h>

static char digits[] = "0123456789abcdef"; /**< Hexadecimal characters */
static spinlock_t printflock;              /**< printf spinlock */

#define DEFAULT_DOUBLE_PRECISION 16
#define DEFAULT_DOUBLE_BUFFER_SIZE 128

void print_double(double num, __u8 modifier, __u16 precision) 
{
	double intval,intval2;
	int counter;
	int exponent,exponenttmp;
	unsigned char buf[DEFAULT_DOUBLE_BUFFER_SIZE];
	unsigned long in1,in2;	
	

	if (fmath_is_nan(num)) {
		print_str("NaN");
		return;
	}
	
	if (num<0.0) {
		putchar('-');
		num=num*-1.0;
	}


	if (fmath_is_infinity(num)) {
		print_str("Inf");
		return;
	}

	if ((modifier=='E')||(modifier=='e')) {
		intval2=fmath_fint(fmath_get_decimal_exponent(num),&intval);
		exponent=intval;
		if ((intval2<0.0)) exponent--;
		num = num / ((fmath_dpow(10.0,exponent)));
		
		print_double(num,modifier+1,precision); /* modifier+1 = E => F or e => f */
		putchar(modifier);
		if (exponent<0) {
			putchar('-');
			exponent*=-1;
		}
		print_number(exponent,10);
		return;
	}
		
	/* TODO: rounding constant - when we got fraction >= 0.5, we must increment last printed number */

	/* 
	 * Here is a problem with cumulative error while printing big double values -> we will divide
	 * the number with a power of 10, print new number with better method for small numbers and
	 * then print decimal point at correct position.
	 */
	
	fmath_fint(fmath_get_decimal_exponent(num),&intval);
	
	exponent=(intval>0.0?intval:0);
	
	precision+=exponent;
	
	if (exponent>0) num = num / ((fmath_dpow(10.0,exponent)));
		
	num=fmath_fint(num,&intval);
	
	if (precision>0) {
		counter=precision-1;
		if (exponent>0) counter++;
		
		if (counter>=DEFAULT_DOUBLE_BUFFER_SIZE) {
			counter=DEFAULT_DOUBLE_BUFFER_SIZE;
		}
		exponenttmp=exponent;
		while(counter>=0) {
			num *= 10.0;
			num = fmath_fint(num,&intval2);
			buf[counter--]=((int)intval2)+'0';
			exponenttmp--;
			if ((exponenttmp==0)&&(counter>=0)) buf[counter--]='.';
		}
		counter=precision;
		if ((exponent==0)&&(counter<DEFAULT_DOUBLE_BUFFER_SIZE)) buf[counter]='.';
		counter++;	
	} else {
		counter=0;	
	}
	
	in1=intval;
	if (in1==0.0) {
		if (counter<DEFAULT_DOUBLE_BUFFER_SIZE) buf[counter++]='0';
	} else {
		while(( in1>0 )&&(counter<DEFAULT_DOUBLE_BUFFER_SIZE)) {
			
			in2=in1;
			in1/=10;
			buf[counter]=in2-in1*10 + '0';
			counter++;
		}
	}
	
	counter = (counter>=DEFAULT_DOUBLE_BUFFER_SIZE?DEFAULT_DOUBLE_BUFFER_SIZE:counter);
	while (counter>0) {
		putchar(buf[--counter]);
	}
	return;
}

/** Print NULL terminated string
 *
 * Print characters from str using putchar() until
 * \x00 character is reached.
 *
 * @param str Characters to print.
 *
 */
void print_str(const char *str)
{
	int i = 0;
	char c;
	
	while (c = str[i++])
		putchar(c);
}


/** Print hexadecimal digits
 *
 * Print fixed count of hexadecimal digits from
 * the number num. The digits are printed in
 * natural left-to-right order starting with
 * the width-th digit.
 *
 * @param num   Number containing digits.
 * @param width Count of digits to print.
 *
 */
void print_fixed_hex(const __u64 num, const int width)
{
	int i;
    
	for (i = width*8 - 4; i >= 0; i -= 4)
	    putchar(digits[(num>>i) & 0xf]);
}


/** Print number in given base
 *
 * Print significant digits of a number in given
 * base.
 *
 * @param num  Number to print.
 * @param base Base to print the number in (should
 *             be in range 2 .. 16).
 *
 */
void print_number(const __native num, const unsigned int base)
{
	int val = num;
	char d[sizeof(__native)*8+1];		/* this is good enough even for base == 2 */
	int i = sizeof(__native)*8-1;
	
	do {
		d[i--] = digits[val % base];
	} while (val /= base);
	
	d[sizeof(__native)*8] = 0;	
	print_str(&d[i + 1]);
}


/** General formatted text print
 *
 * Print text formatted according the fmt parameter
 * and variant arguments. Each formatting directive
 * begins with % (percentage) character and one of the
 * following character:
 *
 * %    Prints the percentage character.
 * s    The next variant argument is treated as char*
 *      and printed as a NULL terminated string.
 * c    The next variant argument is treated as a single char.
 * p    The next variant argument is treated as a maximum
 *      bit-width integer with respect to architecture
 *      and printed in full hexadecimal width.
 * P    As with 'p', but '0x' is prefixed.
 * q    The next variant argument is treated as a 64b integer
 *      and printed in full hexadecimal width.
 * Q    As with 'q', but '0x' is prefixed.
 * l    The next variant argument is treated as a 32b integer
 *      and printed in full hexadecimal width.
 * L    As with 'l', but '0x' is prefixed.
 * w    The next variant argument is treated as a 16b integer
 *      and printed in full hexadecimal width.
 * W    As with 'w', but '0x' is prefixed.
 * b    The next variant argument is treated as a 8b integer
 *      and printed in full hexadecimal width.
 * N    As with 'b', but '0x' is prefixed.
 * d    The next variant argument is treated as integer
 *      and printed in standard decimal format (only significant
 *      digits).
 * x    The next variant argument is treated as integer
 *      and printed in standard hexadecimal format (only significant
 *      digits).
 * X    As with 'x', but '0x' is prefixed.
 * .    The decimal number following period will be treated as precision
 *      for printing floating point numbers. One of 'e', 'E', 'f' or 'F'
 *      must follow.
 * e    The next variant argument is treated as double precision float
 *      and printed in exponent notation with only one digit before decimal point
 *      in specified precision. The exponent sign is printed as 'e'.
 * E    As with 'e', but the exponent sign is printed as 'E'.
 * f    The next variant argument is treated as double precision float
 *      and printed in decimal notation in specified precision.
 * F    As with 'f'.
 *
 * All other characters from fmt except the formatting directives
 * are printed in verbatim.
 *
 * @param fmt Formatting NULL terminated string.
 *
 */
void printf(const char *fmt, ...)
{
	int irqpri, i = 0;
	va_list ap;
	char c;	
	
	__u16 precision;
	
	va_start(ap, fmt);

	irqpri = cpu_priority_high();
	spinlock_lock(&printflock);

	while (c = fmt[i++]) {
		switch (c) {

		    /* control character */
		    case '%':
			precision = DEFAULT_DOUBLE_PRECISION;
			if (fmt[i]=='.') {
				precision=0;
				c=fmt[++i];
				while((c>='0')&&(c<='9')) {
					precision = precision*10 + c - '0';
					c=fmt[++i];
				}
			}
		    
			switch (c = fmt[i++]) {

			    /* percentile itself */
			    case '%':
				break;

			    /*
			     * String and character conversions.
			     */
			    case 's':
				print_str(va_arg(ap, char_ptr));
				goto loop;

			    case 'c':
				c = (char) va_arg(ap, int);
				break;

			    /*
		             * Hexadecimal conversions with fixed width.
		             */
			    case 'P': 
				print_str("0x");
			    case 'p':
	    			print_fixed_hex(va_arg(ap, __native), sizeof(__native));
				goto loop;

			    case 'Q': 
				print_str("0x");
			    case 'q':
		    		print_fixed_hex(va_arg(ap, __u64), INT64);
				goto loop;

			    case 'L': 
				print_str("0x");
			    case 'l':
		    		print_fixed_hex(va_arg(ap, __native), INT32);
				goto loop;

			    case 'W':
				print_str("0x");
			    case 'w':
		    		print_fixed_hex(va_arg(ap, __native), INT16);
				goto loop;

			    case 'B':
				print_str("0x");
			    case 'b':
		    		print_fixed_hex(va_arg(ap, __native), INT8);
				goto loop;

			    /*
		             * Floating point conversions.
		             */
			    case 'F':
		    		print_double(va_arg(ap, double),'F',precision);
				goto loop;
					
			    case 'f':
		    		print_double(va_arg(ap, double),'f',precision);
				goto loop;
				
			    case 'E':
		    		print_double(va_arg(ap, double),'E',precision);
				goto loop;
			    case 'e':
		    		print_double(va_arg(ap, double),'e',precision);
				goto loop;
				
			    /*
		             * Decimal and hexadecimal conversions.
		             */
			    case 'd':
		    		print_number(va_arg(ap, __native), 10);
				goto loop;

			    case 'X':
				print_str("0x");
			    case 'x':
		    		print_number(va_arg(ap, __native), 16);
				goto loop;
	    
			    /*
			     * Bad formatting.
			     */
			    default:
				goto out;
			}

		    default: putchar(c);
		}
	
loop:
		;
	}

out:
	spinlock_unlock(&printflock);
	cpu_priority_restore(irqpri);
	
	va_end(ap);
}