/*
 *  R : A Computer Language for Statistical Data Analysis
 *  Copyright (C) 2002-8     the R Development Core Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, a copy is available at
 *  http://www.r-project.org/Licenses/
 *
 * Originally written by Jonathan Rougier
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <Defn.h>
#include "RBufferUtils.h"

#define MAXLINE MAXELTSIZE

/* 
   This is passed a format that started with % and may include other
   chars, e.g. '.2f abc'.  It's aim is to show that this is a valid
   format from one of the types given in pattern. 
*/

static const char *findspec(const char *str)
{
    /* This is not strict about checking where '.' is allowed.
       It should allow  - + ' ' 0 as flags
       m m. .n n.m as width/precision
    */
    const char *p = str;

    if(*p != '%') return p;
    for(p++; ; p++) {
	if(*p == '-' || *p == '+' || *p == ' ' || *p == '.' ) continue;
	/* '*' will currently have got substituted before this */
	if(*p == '*' || (*p >= '0' && *p <= '9')) continue;
	break;
    }
    return p;
}


/*   FALSE is success, TRUE is an error. */
static Rboolean checkfmt(const char *fmt, const char *pattern)
{
    const char *p =fmt;

    if(*p != '%') return 1;
    p = findspec(fmt);
    return strcspn(p, pattern) != 0;
}


SEXP attribute_hidden do_sprintf(SEXP call, SEXP op, SEXP args, SEXP env)
{
    int i, nargs, cnt, v, thislen, nfmt, nprotect = 1;
    const char *formatString, *ss; char *starc;
    /* fmt2 is a copy of fmt with '*' expanded.
       bit will hold numeric formats and %<w>s, so be quite small. */
    char fmt[MAXLINE+1], fmt2[MAXLINE+10], *fmtp, bit[MAXLINE+1],
	*outputString;
    size_t n, cur, chunk;

    SEXP format, ans, _this, a[100], tmp;
    int ns, maxlen, lens[100], nthis, has_star, star_arg = 0, nstar;
    static R_StringBuffer outbuff = {NULL, 0, MAXELTSIZE};
    Rboolean use_UTF8;

    outputString = R_AllocStringBuffer(0, &outbuff);

    /* grab the format string */
    nargs = length(args);
    format = CAR(args);
    if (!isString(format) || length(format) == 0)
	error(_("'fmt' is not a non-empty character vector"));
    args = CDR(args); nargs--;
    if(nargs >= 100)
	error(_("only 100 arguments are allowed"));

    /* record the args for possible coercion and later re-ordering */
    for(i = 0; i < nargs; i++, args = CDR(args)) a[i] = CAR(args);

    maxlen = nfmt = length(format);
    for(i = 0; i < nargs; i++) {
	lens[i] = length(a[i]);
	if(lens[i] == 0)
	    error(_("zero-length argument"));
	if(maxlen < lens[i]) maxlen = lens[i];
    }
    if(maxlen % length(format))
	error(_("arguments cannot be recycled to the same length"));
    for(i = 0; i < nargs; i++)
	if(maxlen % lens[i])
	    error(_("arguments cannot be recycled to the same length"));

    /* We do the format analysis a row at a time */
    PROTECT(ans = allocVector(STRSXP, maxlen));
    for(ns = 0; ns < maxlen; ns++) {
	outputString[0] = '\0';
	use_UTF8 = getCharCE(STRING_ELT(format, ns % nfmt)) == CE_UTF8;
	if (!use_UTF8) {
	    for(i = 0; i < nargs; i++) {
		if (!isString(a[i])) continue;
		if (getCharCE(STRING_ELT(a[i], ns % lens[i])) == CE_UTF8) {
		    use_UTF8 = TRUE; break;
		}
	    }
	}
	if (use_UTF8)
	    formatString = translateCharUTF8(STRING_ELT(format, ns % nfmt));
	else
	    formatString = translateChar(STRING_ELT(format, ns % nfmt));
	n = strlen(formatString);
	if (n > MAXLINE)
	    error(_("'fmt' length exceeds maximal format length %d"), MAXLINE);
	/* process the format string */
	for (cur = 0, cnt = 0; cur < n; cur += chunk) {
	    ss = NULL;
	    if (formatString[cur] == '%') { /* handle special format command */

		if (cur < n - 1 && formatString[cur + 1] == '%') {
		    /* take care of %% in the format */
		    chunk = 2;
		    strcpy(bit, "%");
		}
		else {
		    /* recognise selected types from Table B-1 of K&R */
		    /* This is MBCS-OK, as we are in a format spec */
		    chunk = strcspn(formatString + cur + 1, "aAdisfeEgGxX%") + 2;
		    if (cur + chunk > n)
			error(_("unrecognised format at end of string"));

		    strncpy(fmt, formatString + cur, chunk);
		    fmt[chunk] = '\0';

		    nthis = -1;
		    /* now look for %n$ or %nn$ form */
		    if (strlen(fmt) > 3 && fmt[1] >= '1' && fmt[1] <= '9') {
			v = fmt[1] - '0';
			if(fmt[2] == '$') {
			    if(v > nargs)
				error(_("reference to non-existent argument %d"), v);
			    nthis = v-1;
			    memmove(fmt+1, fmt+3, strlen(fmt)-2);
			} else if(fmt[2] >= '1' && fmt[2] <= '9'
				  && fmt[3] == '$') {
			    v = 10*v + fmt[2] - '0';
			    if(v > nargs)
				error(_("reference to non-existent argument %d"), v);
			    nthis = v-1;
			    memmove(fmt+1, fmt+4, strlen(fmt)-3);
			}
		    }

		    has_star = 0;
		    starc = Rf_strchr(fmt, '*');
		    if (starc) { /* handle * format if present */
			nstar = -1;
			if (strlen(starc) > 3 && starc[1] >= '1' && starc[1] <= '9') {
			    v = starc[1] - '0';
			    if(starc[2] == '$') {
				if(v > nargs)
				    error(_("reference to non-existent argument %d"), v);
				nstar = v-1;
				memmove(starc+1, starc+3, strlen(starc)-2);
			    } else if(starc[2] >= '1' && starc[2] <= '9'
				      && starc[3] == '$') {
				v = 10*v + starc[2] - '0';
				if(v > nargs)
				    error(_("reference to non-existent argument %d"), v);
				nstar = v-1;
				memmove(starc+1, starc+4, strlen(starc)-3);
			    }
			}

			if(nstar < 0) {
			    if (cnt >= nargs) error(_("too few arguments"));
			    nstar = cnt++;
			}

			if (Rf_strchr(starc+1, '*'))
			    error(_("at most one asterisk '*' is supported in each conversion specification"));

			_this = a[nstar];
			if(ns == 0 && TYPEOF(_this) == REALSXP) {
			    _this = coerceVector(_this, INTSXP);
			    PROTECT(a[nstar] = _this);
			    nprotect++;
			}
			if(TYPEOF(_this) != INTSXP || LENGTH(_this)<1 ||
			   INTEGER(_this)[ns % LENGTH(_this)] == NA_INTEGER)
			    error(_("argument for '*' conversion specification must be a number"));
			has_star = 1;
			star_arg = INTEGER(_this)[ns % LENGTH(_this)];
		    }

		    if (fmt[strlen(fmt) - 1] == '%') {
			/* handle % with formatting options */
			if (has_star)
			    sprintf(bit, fmt, star_arg);
			else
			    sprintf(bit, fmt);
		    } else {
			if(nthis < 0) {
			    if (cnt >= nargs) error(_("too few arguments"));
			    nthis = cnt++;
			}
			_this = a[nthis];
			if (has_star) {
			    char *p, *q = fmt2;
			    for (p = fmt; *p; p++)
				if (*p == '*') q += sprintf(q, "%d", star_arg);
				else *q++ = *p;
			    *q = '\0';
			    fmtp = fmt2;
			} else fmtp = fmt;

			if(ns == 0) {
			    /* Now let us see if some minimal coercion
			       would be sensible, but only do so once. */
			    switch(*findspec(fmtp)) {
			    case 'd':
			    case 'i':
			    case 'x':
			    case 'X':
				if(TYPEOF(_this) == REALSXP) {
				    double r = REAL(_this)[0];
				    if((double)((int) r) == r)
					_this = coerceVector(_this, INTSXP);
				    PROTECT(a[nthis] = _this);
				    nprotect++;
				}
				break;
			    case 'a':
			    case 'A':
			    case 'e':
			    case 'f':
			    case 'g':
			    case 'E':
			    case 'G':
				if(TYPEOF(_this) != REALSXP) {
				    PROTECT(tmp = lang2(install("as.double"), _this));
				    _this = eval(tmp, env);
				    UNPROTECT(1);
				    PROTECT(a[nthis] = _this);
				    nprotect++;
				}
				break;
			    case 's':
				if(TYPEOF(_this) != STRSXP) {
				    PROTECT(tmp = lang2(install("as.character"), _this));
				    _this = eval(tmp, env);
				    UNPROTECT(1);
				    PROTECT(a[nthis] = _this);
				    nprotect++;
				}
				break;
			    default:
				break;
			    }
			}

			PROTECT(_this);
			thislen = length(_this);
			if(thislen == 0)
			    error(_("coercion has changed vector length to 0"));

			switch(TYPEOF(_this)) {
			case LGLSXP:
			    {
				int x = LOGICAL(_this)[ns % thislen];
				if (checkfmt(fmtp, "di"))
				    error("%s",
					  _("use format %d or %i for logical objects"));
				if (x == NA_LOGICAL) {
				    fmtp[strlen(fmtp)-1] = 's';
				    sprintf(bit, fmtp, "NA");
				} else {
				    sprintf(bit, fmtp, x);
				}
				break;
			    }
			case INTSXP:
			    {
				int x = INTEGER(_this)[ns % thislen];
				if (checkfmt(fmtp, "dixX"))
				    error("%s",
					  _("use format %d, %i, %x or %X for integer objects"));
				if (x == NA_INTEGER) {
				    fmtp[strlen(fmtp)-1] = 's';
				    sprintf(bit, fmtp, "NA");
				} else {
				    sprintf(bit, fmtp, x);
				}
				break;
			    }
			case REALSXP:
			    {
				double x = REAL(_this)[ns % thislen];
				if (checkfmt(fmtp, "aAfeEgG"))
				    error("%s",
					  _("use format %f, %e, %g or %a for numeric objects"));
				if (R_FINITE(x)) {
				    sprintf(bit, fmtp, x);
				} else {
				    char *p = Rf_strchr(fmtp, '.');
				    if (p) {
					*p++ = 's'; *p ='\0';
				    } else
					fmtp[strlen(fmtp)-1] = 's';
				    if (ISNA(x)) {
					if (strcspn(fmtp, " ") < strlen(fmtp))
					    sprintf(bit, fmtp, " NA");
					else
					    sprintf(bit, fmtp, "NA");
				    } else if (ISNAN(x)) {
					if (strcspn(fmtp, " ") < strlen(fmtp))
					    sprintf(bit, fmtp, " NaN");
					else
					    sprintf(bit, fmtp, "NaN");
				    } else if (x == R_PosInf) {
					if (strcspn(fmtp, "+") < strlen(fmtp))
					    sprintf(bit, fmtp, "+Inf");
					else if (strcspn(fmtp, " ") < strlen(fmtp))
					    sprintf(bit, fmtp, " Inf");
					else
					    sprintf(bit, fmtp, "Inf");
				    } else if (x == R_NegInf)
					sprintf(bit, fmtp, "-Inf");
				}
				break;
			    }
			case STRSXP:
			    /* NA_STRING will be printed as 'NA' */
			    if (checkfmt(fmtp, "s"))
				error("%s", _("use format %s for character objects"));
			    if (use_UTF8)
				ss = translateCharUTF8(STRING_ELT(_this, ns % thislen));
			    else
				ss = translateChar(STRING_ELT(_this, ns % thislen));
			    if(fmtp[1] != 's') {
				if(strlen(ss) > MAXLINE)
				    warning(_("likely truncation of character string to %d characters"),
					    MAXLINE-1);
				snprintf(bit, MAXLINE, fmtp, ss);
				bit[MAXLINE] = '\0';
				ss = NULL;
			    }
			    break;

			default:
			    error(_("unsupported type"));
			    break;
			}

			UNPROTECT(1);
		    }
		}
	    }
	    else { /* not '%' : handle string part */
		char *ch = Rf_strchr(formatString + cur, '%'); /* MBCS-aware
								  version used */
		if(ch) chunk = ch - formatString - cur;
		else chunk = strlen(formatString + cur);
		strncpy(bit, formatString + cur, chunk);
		bit[chunk] = '\0';
	    }
	    if(ss) {
		outputString = R_AllocStringBuffer(strlen(outputString) +
						   strlen(ss) + 1, &outbuff);
		strcat(outputString, ss);
	    } else {
		outputString = R_AllocStringBuffer(strlen(outputString) +
						   strlen(bit) + 1, &outbuff);
		strcat(outputString, bit);
	    }
	}
	SET_STRING_ELT(ans, ns, mkCharCE(outputString, 
					 use_UTF8 ? CE_UTF8 : CE_NATIVE));
    }

    UNPROTECT(nprotect);
    R_FreeStringBufferL(&outbuff);
    return ans;
}

/* Local Variables: */
/* indent-tabs-mode: t */
/* c-basic-offset: 4 */
/* End: */