/*
 *	PROGRAM:	InterBase International support
 *	MODULE:		lc_big5.c
 *	DESCRIPTION:	Language Drivers in the BIG5 family.  
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 */

#include "firebird.h"
#include "../intl/ldcommon.h"

/* These macros have a duplicate in cv_big5.c */
#define	BIG51(uc)	((UCHAR)((uc)&0xff)>=0xa1 && \
			 (UCHAR)((uc)&0xff)<=0xfe)	/* BIG-5 1st-byte */
#define	BIG52(uc)	((UCHAR)((uc)&0xff)>=0x40 && \
			 (UCHAR)((uc)&0xff)<=0xfe)	/* BIG-5 2nd-byte */

extern USHORT famasc_key_length();
extern USHORT famasc_string_to_key();
extern SSHORT famasc_compare();
static USHORT big5_to_upper();
static USHORT big5_to_lower();
static SSHORT big5_str_to_upper();
extern USHORT CVBIG5_big5_byte2short();
extern SSHORT CVBIG5_big5_mbtowc();


#define FAMILY_MULTIBYTE(id_number, name, charset, country) \
	cache->texttype_version =		IB_LANGDRV_VERSION; \
	cache->texttype_type =			(id_number); \
	cache->texttype_character_set =		(charset); \
	cache->texttype_country =		(country); \
	cache->texttype_bytes_per_char =	2; \
	cache->texttype_fn_init =		(FPTR_SHORT) (name); \
	cache->texttype_fn_key_length =		famasc_key_length; \
	cache->texttype_fn_string_to_key =	famasc_string_to_key; \
	cache->texttype_fn_compare =		famasc_compare; \
        cache->texttype_fn_to_upper =           big5_to_upper; \
        cache->texttype_fn_to_lower =           big5_to_lower; \
        cache->texttype_fn_str_to_upper =       big5_str_to_upper; \
	cache->texttype_collation_table =	(BYTE *) NULL; \
	cache->texttype_toupper_table =		(BYTE *) NULL; \
	cache->texttype_tolower_table =		(BYTE *) NULL; \
	cache->texttype_compress_table =	(BYTE *) NULL; \
	cache->texttype_expand_table =		(BYTE *) NULL; \
	cache->texttype_name =			POSIX;



TEXTTYPE_ENTRY(BIG5_init)
{
	static const ASCII POSIX[] = "C.BIG5";

	FAMILY_MULTIBYTE(500, BIG5_init, CS_BIG5, CC_C);
	cache->texttype_fn_to_wc = CVBIG5_big5_byte2short;
	cache->texttype_fn_mbtowc = CVBIG5_big5_mbtowc;

	TEXTTYPE_RETURN;
}

#include "../intl/collations/undef.h"



#undef FAMILY_MULTIBYTE




#define ASCII_LOWER_A	'a'
#define ASCII_UPPER_A	'A'
#define ASCII_LOWER_Z	'z'
#define ASCII_UPPER_Z	'Z'

/*
 *	Note: This function expects Wide-Char input, not
 *	Multibyte input
 */
STATIC USHORT big5_to_upper(obj, ch)
	 TEXTTYPE obj;
	 UCS2_CHAR ch;
{
	if (ch >= (UCS2_CHAR) ASCII_LOWER_A && ch <= (UCS2_CHAR) ASCII_LOWER_Z)
		return (ch - (UCS2_CHAR) ASCII_LOWER_A + (UCS2_CHAR) ASCII_UPPER_A);
	return ch;
}


/*
 *	Returns -1 if output buffer was too small
 */
/*
 *	Note: This function expects Multibyte input
 */
STATIC SSHORT big5_str_to_upper(obj, iLen, pStr, iOutLen, pOutStr)
	 TEXTTYPE obj;
	 USHORT iLen;
	 BYTE *pStr;
	 USHORT iOutLen;
	 BYTE *pOutStr;
{
	BYTE *p;
	USHORT waiting_for_big52 = FALSE;
	BYTE c;

	assert(pStr != NULL);
	assert(pOutStr != NULL);
	assert(iLen <= 32000);		/* almost certainly an error */
	assert(iOutLen <= 32000);	/* almost certainly an error */
	assert(iOutLen >= iLen);
	p = pOutStr;
	while (iLen && iOutLen) {
		c = *pStr++;
		if (waiting_for_big52 || BIG51(c)) {
			waiting_for_big52 = !waiting_for_big52;
		}
		else {
			if (c >= ASCII_LOWER_A && c <= ASCII_LOWER_Z)
				c = (c - ASCII_LOWER_A + ASCII_UPPER_A);
		}
		*pOutStr++ = c;
		iLen--;
		iOutLen--;
	}
	if (iLen != 0)
		return (-1);			/* Must have ran out of output space */
	return (pOutStr - p);
}




/*
 *	Note: This function expects Wide-Char input, not
 *	Multibyte input
 */
STATIC USHORT big5_to_lower(obj, ch)
	 TEXTTYPE obj;
	 UCS2_CHAR ch;
{
	if (ch >= (UCS2_CHAR) ASCII_UPPER_A && ch <= (UCS2_CHAR) ASCII_UPPER_Z)
		return (ch - (UCS2_CHAR) ASCII_UPPER_A + (UCS2_CHAR) ASCII_LOWER_A);
	return ch;
}