/*
 * The original was spagetti. I have replaced Michael's code with some of
 * my own which is a thousand times more readable and can also handle '%',
 * which substitutes anything except a space. This should enable people
 * to position things better based on argument. I have also added '?', which
 * substitutes to any single character. And of course it still handles '*'.
 * this should be more efficient than the previous version too.
 *
 * Thus this whole file becomes:
 *
 * Written By Troy Rollo
 *
 * Copyright(c) 1992
 *
 * See the COPYRIGHT file, or do a HELP IRCII COPYRIGHT 
 */

#include "irc.h"
#include "ircaux.h"
#include "output.h"


#ifdef OLD_MATCH

static	int	total_explicit;

/*
 * The following #define is here because we *know* its behaviour.
 * The behaviour of toupper tends to be undefined when it's given
 * a non lower case letter.
 * All the systems supported by IRCII should be ASCII
 */
#define	mkupper(c)	(((c) >= 'a' && (c) <= 'z') ? ((c) - 'a' + 'A') : c)

int match(register char *pattern, register char *string)
{
	char	type = 0;

	while (*string && *pattern && *pattern != '*' && *pattern != '%')
	{
		if (*pattern == '\\' && pattern[1])
		{
			if (!*++pattern || !(mkupper(*pattern) == mkupper(*string)))
				return 0;
			else
				pattern++, string++, total_explicit++;
		}


		if (*pattern == '?')
			pattern++, string++;
		else if (mkupper(*pattern) == mkupper(*string))
			pattern++, string++, total_explicit++;
		else
			break;
	}
	if (*pattern == '*' || *pattern == '%')
	{
		type = (*pattern++);
		while (*string)
		{
			if (match(pattern, string))
				return 1;
			else if (type == '*' || *string != ' ')
				string++;
			else
				break;
		}
	}

	/* Slurp up any trailing *'s or %'s... */
	if (!*string && (type == '*' || type == '%'))
		while (*pattern && (*pattern == '*' || *pattern == '%'))
			pattern++;

	if (!*string && !*pattern)
		return 1;

	return 0;
}

/*
 * This version of wild_match returns 1 + the  count  of characters
 * explicitly matched if a match occurs. That way we can look for
 * the best match in a list
 */
/* \\[ and \\] handling done by Jeremy Nelson
 * EPIC will not use the new pattern matcher currently used by 
 * ircii because i am not convinced that it is 1) better * and 
 * 2) i think the \\[ \\] stuff is important.
 */
int wild_match (register char *pattern, register char *str)
{
	register char *ptr;
	char *ptr2 = pattern;
	int nest = 0;
	char my_buff[2048];
	char *arg;
	int best_total = 0;

	total_explicit = 0;

	/* Is there a \[ in the pattern to be expanded? */
	/* This stuff here just reduces the \[ \] set into a series of
	 * one-simpler patterns and then recurses */
	if ((ptr2 = strstr(pattern, "\\[")))
	{
		/* we will have to null this out, but not until weve used it */
		char *placeholder = ptr2;
		ptr = ptr2;

		/* yes. whats the character after it? (first time
		   through is a trivial case) */
		do
		{
			switch (ptr[1]) 
			{
					/* step over it and add to nest */
				case '[' :  ptr2 = ptr + 2 ;
					    nest++;
					    break;
					/* step over it and remove nest */
				case ']' :  ptr2 = ptr + 2;
					    nest--;
					    break;
				default:
					if (*ptr == '\\')
						ptr2++;
			}
		}
		/* 
		 * Repeat while there are more backslashes to look at and
		 * we have are still in nested \[ \] sets
		 */
		while ((nest) && (ptr = index(ptr2, '\\')));

		/* right now, we know ptr points to a \] or to null */
		/* remember that && short circuits and that ptr will 
		   not be set to null if (nest) is zero... */
		if (ptr)
		{
			/* null out and step over the original \[ */
			*placeholder = '\0';
			placeholder += 2;

			/* null out and step over the matching \] */
			*ptr = '\0';
			ptr +=2;

			/* 
			 * grab words ("" sets or space words) one at a time
			 * and attempt to match all of them.  The best value
			 * matched is the one used.
			 */
			while ((arg = new_next_arg(placeholder, &placeholder)))
			{
				int tmpval;
				strcpy(my_buff, pattern);
				strcat(my_buff, arg);
				strcat(my_buff, ptr);

				/* the total_explicit we return is whichever
				 * pattern has the highest total_explicit */
				if ((tmpval = wild_match(my_buff, str)))
				{
					if (tmpval > best_total)
						best_total = tmpval;
				}
			}
			return best_total; /* end of expansion section */
		}
		/* Possibly an unmatched \[ \] set */
		else
		{
			total_explicit = 0;
			if (match(pattern, str))
				return total_explicit + 1;
			else
				return 0;
		}
	}
	/* trivial case (no expansion) when weve expanded all the way out */
	else if (match(pattern, str))
		return total_explicit+1;
	else
		return 0;
}

#else		/* NEW MATCH */

/*
 * Written By Douglas A. Lewis <dalewis@cs.Buffalo.EDU>
 *
 * This file is in the public domain.
 */

#include "irc.h"

#include "ircaux.h"

static	int	_wild_match _((u_char *, u_char *));

#define RETURN_FALSE -1
#define RETURN_TRUE count

u_char lower_tab[256] = 
{
  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
 64, 97, 98, 99,100,101,102,103,104,105,106,107,108,109,110,111,
112,113,114,115,116,117,118,119,120,121,122, 91, 92, 93, 94, 95,
 96, 97, 98, 99,100,101,102,103,104,105,106,107,108,109,110,111,
112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,
128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
144,145,145,147,148,149,150,151,152,153,154,155,156,157,158,159,
160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,
176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,
192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,
208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,
224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,
240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255
};

#undef tolower		/* don't want previous version. */
#define tolower(x) lower_tab[x]

/*
 * So I don't make the same mistake twice: We don't need to check for '\\'
 * in the input (string to check) because it doesn't have a special meaning
 * in that context.
 *
 * We don't need to check for '\\' when we come accross a * or % .. The rest
 * of the routine will do that for us.
 */

static	int
_wild_match(mask, string)
	u_char	*mask,
		*string;
{
	u_char	*m = mask,
		*n = string,
		*ma = NULL,
		*na = NULL,
		*mp = NULL,
		*np = NULL;
	int	just = 0,
		pcount = 0,
		acount = 0,
		count = 0;

	for (;;)
	{
		if (*m == '*')
		{
			ma = ++m;
			na = n;
			just = 1;
			mp = NULL;
			acount = count;
		}
		else if (*m == '%')
		{
			mp = ++m;
			np = n;
			pcount = count;
		}
		else if (*m == '?')
		{
			m++;
			if (!*n++)
				return RETURN_FALSE;
		}
		else
		{
			if (*m == '\\')
			{
				m++;
				/* Quoting "nothing" is a bad thing */
				if (!*m)
					return RETURN_FALSE;
			}
			if (!*m)
			{
				/*
				 * If we are out of both strings or we just
				 * saw a wildcard, then we can say we have a
				 * match
				 */
				if (!*n)
					return RETURN_TRUE;
				if (just)
					return RETURN_TRUE;
				just = 0;
				goto not_matched;
			}
			/*
			 * We could check for *n == NULL at this point, but
			 * since it's more common to have a character there,
			 * check to see if they match first (m and n) and
			 * then if they don't match, THEN we can check for
			 * the NULL of n
			 */
			just = 0;
			if (tolower(*m) == tolower(*n))
			{
				m++;
				if (*n == ' ')
					mp = NULL;
				count++;
				n++;
			}
			else
			{

	not_matched:

				/*
				 * If there are no more characters in the
				 * string, but we still need to find another
				 * character (*m != NULL), then it will be
				 * impossible to match it
				 */
				if (!*n)
					return RETURN_FALSE;
				if (mp)
				{
					m = mp;
					if (*np == ' ')
					{
						mp = NULL;
						goto check_percent;
					}
					n = ++np;
					count = pcount;
				}
				else
	check_percent:

				if (ma)
				{
					m = ma;
					n = ++na;
					count = acount;
				}
				else
					return RETURN_FALSE;
			}
		}
	}
}

int match(char *pattern, char *string)
{
/* -1 on false >= 0 on true */
  return ((_wild_match(pattern, string)>=0)?1:0);
}

int
wild_match(pattern, str)
	char	*pattern,
		*str;
{
	/* assuming a -1 return of false */
	return _wild_match((u_char *) pattern, (u_char *) str) + 1;
}

#endif	/* NEW MATCH */
