/* ctype.c -- Copyright 1996 Liam R. E. Quin.
 * All Rights Reserved.
 * This code is NOT in the public domain.
 * See the file COPYRIGHT for full details.
 */

/* ctype -- character types
 * Liam Quin, June 1996 and later...
 *
 * $Id: ctype.c,v 1.4 2001/05/31 03:50:13 liam Exp $ 
 */

#include "error.h"
#include "globals.h" /* defines and declarations for database filenames */

#include <stdio.h>

#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_STRING_H
# include <string.h>
#else
# include <strings.h>
#endif
#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#else
# include <malloc.h>
#endif

#include <locale.h> /* comment out if you don't have it */

#include "fileinfo.h"
#include "wordinfo.h"
#include "wordrules.h"
#include "emalloc.h"
#include "chartype.h"
#include "liblqtext.h"
#include "lqtrace.h"

/** System calls and library routines used in this file: **/
/** System calls: **/
/** Library Functions: **/
#ifndef toupper
 extern int toupper(
#  ifdef HAVE_PROTO
    int theChar
#  endif
 );
#endif

#ifndef tolower
 extern int tolower(
#  ifdef HAVE_PROTO
    int theChar
#  endif
 );
#endif

/** Functions within this file that need declaring: **/
/**/

/* <Function>
 *   <Name>LQT_InitialiseCharacterTypes
 *   <Class>Database/Defaults, Database/Words, Language/Stemming
 *   <Purpose>
 *      <P>Initialises the tables used to determine whether a given
 *	character is part of a word or not.</P>
 *	<P>This function is called automatically by LQT_OpenDatabase().</P>
 *   <Returns>
 *      zero on success.
 * </Function>
 */
LIBRARY void
LQTp_InitialiseCharacterTypes(db)
    t_LQTEXT_Database *db;
{
    register int i, value;
    char *newLocale;
    char *PreferredLocale = LQT_GetOption(&db->Options, "locale");

#ifdef LC_CTYPE
    if (PreferredLocale) {
	newLocale = setlocale(LC_CTYPE, PreferredLocale);
	if (!newLocale) {
	    Error(E_FATAL,
		"%s: invalid LC_CTYPE locale \"%s\"; check $LANG is OK",
		db->ConfigurationFile,
		PreferredLocale
	    );
	}
    } else {
	newLocale = setlocale(LC_CTYPE, "");
    }

    if (newLocale) {
	if (!PreferredLocale) {
	    PreferredLocale = "not found in config file";
	}
	LQT_Trace(LQTRACE_DEBUG|LQTRACE_VERBOSE,
	    "Locale (%s) set to %s", PreferredLocale, newLocale
	);
    } else {
	Error(E_WARN, "Locale not set; check $LANG and $LC_CTYPE");
    }
#endif

    for (i = 0; i < 256; i++) {
	db->ctypeTable[i] = 0;
	db->upperTable[i] = 0;
	db->lowerTable[i] = 0;
    }

    if (db->IndexNumbers == 0) {
	db->ctypeTable[LQT_DIGIT_TO_IGNORE] |= (LQT_C_ISDIGIT|LQT_C_STARTS_WORD);
    }

    /* this should really support reading an external character table. */
    for (i = 0; i < 256; i++) {
	value = 0;

	if (isupper(i)) {
	    value |= LQT_C_ISUPPER;
	    db->lowerTable[i] = tolower(i);
	} else  if (islower(i)) {
	    value |= LQT_C_ISLOWER;
	    db->upperTable[i] = toupper(i);
	}

	/* toupper(some_non_alphabetical_character) could return
	 * anything, but it might as well return its argument...
	 *
	 * same for tolower()...
	 *
	 * only set these if they are not already set, so as not
	 * to overwrite asymmetrical values...
	 */
	if (!db->upperTable[i]) {
	    db->upperTable[i] = i;
	}
	if (!db->lowerTable[i]) {
	    db->lowerTable[i] = i;
	}

	if (isdigit(i)) {
	    value |= LQT_C_ISDIGIT;
	}

	if (ispunct(i)) {
	    value |= LQT_C_ISPUNCT;
	}

	if (isalpha(i)) {
	    value |= LQT_C_ISALPHA;
	}

	/* starts word */
	if (LQT_StartsWord(db, i)) {
	    value |= LQT_C_STARTS_WORD;
	}

	/* a word character when surrounded by other word chars */
	if (LQT_OnlyWithinWord(db, i)) {
	    value |= LQT_C_ONLY_WITHIN_WORD;
	}

	/* only in the word if at the end of the word */
	if (LQT_EndsWord(db, i)) {
	    value |= LQT_C_ENDS_WORD;
	}

	db->ctypeTable[i] = value;
    }
    db->ctypeTable[LQT_CHAR_TO_IGNORE] |= LQT_C_ISLOWER;
    db->ctypeTable[LQT_CHAR_TO_IGNORE] |= LQT_C_ISALPHA;
    db->lowerTable[LQT_CHAR_TO_IGNORE] = LQT_CHAR_TO_IGNORE;
    db->upperTable[LQT_CHAR_TO_IGNORE] = LQT_CHAR_TO_IGNORE;
}