/* $Id: codeconv.c,v 1.3 1999/05/31 23:35:26 sybalsky Exp $ (C) Copyright Venue, All Rights Reserved
 */

/************************************************************************/
/*									*/
/*	(C) Copyright 1989-95 Venue. All Rights Reserved.		*/
/*	Manufactured in the United States of America.			*/
/*									*/
/************************************************************************/

#include "version.h"

/*************************************************/
/* NSFatchar string <-> EUC character string	 */
/* conversion program 				 */
/* file name : char_codes.c			 */
/* 26,Jun,'89					 */
/* 5,Aug,'89					 */
/* by Shinichi Miyamoto				 */
/* 10,Jan,'91					 */
/* 27,Feb,'91					 */
/* by Sumie Kurihara (FXIS)			 */
/*************************************************/

#include <stdio.h>

#define EUCMASK 0x80
#define EUCUNMASK 0x7F
#define MASK8BIT 0x00FF
#define TABLESIZE 256

int FatcharNStoEUC(unsigned char *ns_ptr, int ns_len, unsigned char *euc_ptr) {
  int i;
  int euc_len;
  unsigned short ns, euc;
  unsigned short ns_euc(short unsigned int ns);

#ifdef DEBUG
  unsigned char *ptr;
  ptr = euc_ptr;
  printf("FatcharNStoEUC start\n");
  printf("ns_len = %d\n", ns_len);
  for (i = 0; i < ns_len * 2; i++) printf("%x ", ns_ptr[i]);
  printf("\n");
#endif

  /* ns_len convert to byte count */
  ns_len *= 2;

  for (i = euc_len = 0; i < ns_len; i += 2) {
    ns = *ns_ptr++ * TABLESIZE;
    ns += *ns_ptr++;
    euc = ns_euc(ns);
    if (euc / TABLESIZE) {
      /* 16 bit character */
      *euc_ptr++ = euc / TABLESIZE;
      *euc_ptr++ = euc % TABLESIZE;
      euc_len += 2;
    } else {
      /* ASCII character */
      *euc_ptr++ = euc % TABLESIZE;
      ++euc_len;
    }
  }

  *euc_ptr++ = '\0';

#ifdef DEBUG
  printf("FatcharNStoEUC end\n");
  printf("euc_len = %d\n", euc_len);
  for (i = 0; i < euc_len; i++) printf("%x ", ptr[i]);
  printf("\n");
#endif

  return (euc_len);
}

int ThincharNStoEUC(unsigned char *ns_ptr, int ns_len, unsigned char *euc_ptr) {
  int i;
  int euc_len = 0;
  unsigned short ns, euc;
  unsigned short ns_euc(short unsigned int ns);

#ifdef DEBUG
  unsigned char *ptr;
  ptr = euc_ptr;
  printf("ThincharNStoEUC start\n");
  printf("ns_len = %d\n", ns_len);
  for (i = 0; i < ns_len; i++) printf("%x ", ns_ptr[i]);
  printf("\n");
#endif

  /* ns_len convert to byte count */
  for (i = euc_len = 0; i < ns_len; i++) {
    ns = *ns_ptr++;
    euc = ns_euc(ns);
    if (euc / TABLESIZE) {
      /* 16 bit character */
      *euc_ptr++ = euc / TABLESIZE;
      *euc_ptr++ = euc % TABLESIZE;
      euc_len += 2;
    } else {
      /* ASCII character */
      *euc_ptr++ = euc % TABLESIZE;
      ++euc_len;
    }
  }

  *euc_ptr++ = '\0';

#ifdef DEBUG
  printf("ThincharNStoEUC end\n");
  printf("euc_len = %d\n", euc_len);
  for (i = 0; i < euc_len; i++) printf("%x ", ptr[i]);
  printf("\n");
#endif

  return (euc_len);
}

int EUCtoFatcharNS(unsigned char *euc_ptr, unsigned char *ns_ptr) {
  int i;
  int ns_len;
  unsigned short euc, ns;
  unsigned short euc_ns(short unsigned int euc);

#ifdef DEBUG
  printf("EUCtoFatcharNS start\n");
  for (i = 0; i < strlen(euc_ptr); i++) printf("%x ", euc_ptr[i]);
  printf("\n");
#endif

  i = 0;
  while (euc = *euc_ptr++) {
    if (euc & EUCMASK) {
      /* 16 bit character */
      euc *= TABLESIZE;
      euc += *euc_ptr++;
    }

    ns = euc_ns(euc);

    ns_ptr[i++] = ns / TABLESIZE;
    ns_ptr[i++] = ns % TABLESIZE;
  }
  ns_len = i / 2;

#ifdef DEBUG
  printf("EUCtoFatcharNS end\n");
  printf("ns_len = %d\n", ns_len);
  for (i = 0; i < ns_len * 2; i++) printf("%x ", ns_ptr[i]);
  printf("\n");
#endif

  return (ns_len);
}

int EUCstrlen(char *euc_ptr) {
  int len = 0;

#ifdef DEBUG
  int i;

  printf("EUCstrlen start\n");
  for (i = 0; i < strlen(euc_ptr); i++) printf("%x ", euc_ptr[i]);
  printf("\n");
#endif

  while (*euc_ptr)
    if (*euc_ptr & EUCMASK) {
      /* 16 bit character */
      len += 2;
      *euc_ptr++;
      *euc_ptr++;
    } else {
      /* ASCII character */
      len++;
      *euc_ptr++;
    }

#ifdef DEBUG
  printf("EUCstrlen end\n");
  printf("len = %d\n", len);
#endif

  return (len);
}