/*
*******************************************************************************
*
*   Copyright (C) 1998-1999, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*
* File ufmt_cmn.c
*
* Modification History:
*
*   Date        Name        Description
*   12/02/98    stephen     Creation.
*   03/12/99    stephen     Modified for new C API.
*   03/15/99    stephen     Added defaultCPToUnicode, unicodeToDefaultCP
*   07/19/99    stephen     Fixed bug in defaultCPToUnicode
*******************************************************************************
*/

#include "ufmt_cmn.h"
#include "unicode/uchar.h"
#include "unicode/ucnv.h"

int
ufmt_digitvalue(UChar c)
{
  return c - 0x0030 - (c >= 0x0041 ? (c >= 0x0061 ? 39 : 7) : 0);
}

UBool
ufmt_isdigit(UChar     c,
         int32_t     radix)
{
  int digitVal = ufmt_digitvalue(c);
  
  return (digitVal < radix && digitVal >= 0);
}

#define TO_UC_DIGIT(a) a <= 9 ? (0x0030 + a) : (0x0030 + a + 7)
#define TO_LC_DIGIT(a) a <= 9 ? (0x0030 + a) : (0x0030 + a + 39)

void 
ufmt_ltou(UChar     *buffer, 
      int32_t     *len,
      long         value, 
      int32_t     radix,
      UBool    uselower,
      int32_t    minDigits)
{
  int32_t     length     = 0;
  long         q;
  int8_t     digit;
  UChar    *left, *right, temp;
  
  while(value > radix && length < *len) {
    q = value / radix;
    digit = (int8_t)(value - q * radix);
    buffer[length++] = (UChar)(uselower ? TO_LC_DIGIT(digit) 
                 : TO_UC_DIGIT(digit));
    value = q;
  }

  if(length < *len) {
    buffer[length++] = (UChar)(uselower ? TO_LC_DIGIT(value) 
                 : TO_UC_DIGIT(value));
  }

  /* pad with zeroes to make it minDigits long */
  if(minDigits != -1 && length < minDigits) {
    while(length < minDigits && length < *len)
      buffer[length++] = 0x0030;
  }

  /* reverse the buffer */
  left     = buffer;
  right = buffer + length;
  while(left < --right) {
    temp     = *left;
    *left++     = *right;
    *right     = temp;
  }

  *len = length;
}

long
ufmt_utol(const UChar     *buffer, 
      int32_t     *len,
      int32_t     radix)
{
  const UChar     *limit;
  int32_t         count;
  long        result;


  /* intialize parameters */
  limit     = buffer + *len;
  count     = 0;
  result     = 0;

  /* iterate through buffer */
  while(ufmt_isdigit(*buffer, radix) && buffer < limit) {
    
    /* read the next digit */
    result *= radix;
    result += ufmt_digitvalue(*buffer++);
    
    /* increment our count */
    ++count;
  }

  *len = count;
  return result;
}

UBool
ufmt_isws(UChar c)
{
  return (c == 0x0020 || /* space */
      c == 0x0009 || /* tab */
      c == 0x000D || /* CR */
      c == 0x000A || /* LF */
      c == 0x000B || /* vertical tab */
      c == 0x000C || /* form feed */
      u_isspace(c));
}

UChar*
ufmt_defaultCPToUnicode(const char *s,
            int32_t len)
{
  int32_t size;
  UChar *target, *alias;
  UConverter *defConverter;
  UErrorCode status = U_ZERO_ERROR;

  defConverter = ucnv_open(ucnv_getDefaultName(), &status);
  if(U_FAILURE(status) || defConverter == 0)
    return 0;

  /* perform the conversion in one swoop */
  size = (len + 1) / ucnv_getMinCharSize(defConverter);
  target = (UChar*) malloc(size * sizeof(UChar));
  if(target == 0) {
    ucnv_close(defConverter);
    return 0;
  }
  
  alias = target;
  ucnv_toUnicode(defConverter, &alias, alias + size, &s, s + len, 
         NULL, TRUE, &status);

  ucnv_close(defConverter);

  /* add the null terminator */
  *alias = 0x0000;

  return target;
}

char*
ufmt_unicodeToDefaultCP(const UChar *s,
            int32_t len)
{
  int32_t size;
  char *target, *alias;
  UConverter *defConverter;
  UErrorCode status = U_ZERO_ERROR;

  defConverter = ucnv_open(ucnv_getDefaultName(), &status);
  if(U_FAILURE(status) || defConverter == 0)
    return 0;

  /* perform the conversion in one swoop */
  target = (char*) 
    malloc((len + 1) * ucnv_getMaxCharSize(defConverter) * sizeof(char));
  size = (len) * ucnv_getMaxCharSize(defConverter) * sizeof(char);
  if(target == 0) {
    ucnv_close(defConverter);
    return 0;
  }
  
  alias = target;
  ucnv_fromUnicode(defConverter, &alias, alias + size, &s, s + len, 
           NULL, TRUE, &status);

  ucnv_close(defConverter);

  /* add the null terminator */
  *alias = 0x00;

  return target;
}