/*
******************************************************************************
*
*   Copyright (C) 1998-2004, 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 "cstring.h"
#include "cmemory.h"
#include "ufmt_cmn.h"
#include "unicode/uchar.h"
#include "unicode/ucnv.h"
#include "ustr_cnv.h"

#define DIGIT_0     0x0030
#define DIGIT_9     0x0039
#define LOWERCASE_A 0x0061
#define UPPERCASE_A 0x0041
#define LOWERCASE_Z 0x007A
#define UPPERCASE_Z 0x005A

int
ufmt_digitvalue(UChar c)
{
    if( ((c>=DIGIT_0)&&(c<=DIGIT_9)) ||
        ((c>=LOWERCASE_A)&&(c<=LOWERCASE_Z)) ||
        ((c>=UPPERCASE_A)&&(c<=UPPERCASE_Z))  )
    {
      return c - 0x0030 - (c >= 0x0041 ? (c >= 0x0061 ? 39 : 7) : 0);
    }
    else
    {
      return -1;
    }
}

UBool
ufmt_isdigit(UChar     c,
             int32_t     radix)
{
    int digitVal = ufmt_digitvalue(c);

    return (UBool)(digitVal < radix && digitVal >= 0);
}

#define TO_UC_DIGIT(a) a <= 9 ? (0x0030 + a) : (0x0037 + a)
#define TO_LC_DIGIT(a) a <= 9 ? (0x0030 + a) : (0x0057 + a)

void 
ufmt_64tou(UChar     *buffer, 
          int32_t   *len,
          uint64_t  value, 
          uint8_t  radix,
          UBool     uselower,
          int32_t   minDigits)
{
    int32_t  length = 0;
    uint32_t digit;
    UChar    *left, *right, temp;
    
    do {
        digit = (uint32_t)(value % radix);
        value = value / radix;
        buffer[length++] = (UChar)(uselower ? TO_LC_DIGIT(digit) 
            : TO_UC_DIGIT(digit));
    } while(value);

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

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

void 
ufmt_ptou(UChar    *buffer, 
          int32_t   *len,
          void      *value, 
          UBool     uselower)
{
    int32_t i;
    int32_t length = 0;
    uint8_t *ptrIdx = (uint8_t *)&value;

#if U_IS_BIG_ENDIAN
    for (i = 0; i < (int32_t)sizeof(void *); i++)
#else
    for (i = (int32_t)sizeof(void *)-1; i >= 0 ; i--)
#endif
    {
        uint8_t byteVal = ptrIdx[i];
        uint16_t firstNibble = (uint16_t)(byteVal>>4);
        uint16_t secondNibble = (uint16_t)(byteVal&0xF);
        if (uselower) {
            buffer[length++]=TO_LC_DIGIT(firstNibble);
            buffer[length++]=TO_LC_DIGIT(secondNibble);
        }
        else {
            buffer[length++]=TO_UC_DIGIT(firstNibble);
            buffer[length++]=TO_UC_DIGIT(secondNibble);
        }
    }

    *len = length;
}

int64_t
ufmt_uto64(const UChar     *buffer, 
          int32_t     *len,
          int8_t     radix)
{
    const UChar     *limit;
    int32_t         count;
    int64_t        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;
}

void *
ufmt_utop(const UChar     *buffer,
          int32_t     *len)
{
    /*
    TODO: Fix this code so that it will work with pointers that are 2<=sizeof(void*)<=16
    */
    const UChar *limit;
    int32_t     count;
    int64_t     result;
    
    
    /* intialize parameters */
    limit     = buffer + *len;
    count     = 0;
    result    = 0;
    
    /* iterate through buffer */
    /* limit to sixteen iterations since that is the max that an int64_t can contain for pointer work */
    while(ufmt_isdigit(*buffer, 16) && buffer < limit) {
        
        /* read the next digit */
        result *= 16;
        result += ufmt_digitvalue(*buffer++);
        
        /* increment our count */
        ++count;
    }
    
    *len = count;
    return (void *)result;
}

UChar*
ufmt_defaultCPToUnicode(const char *s, int32_t sSize,
                        UChar *target, int32_t tSize)
{
    UChar *alias;
    UErrorCode status = U_ZERO_ERROR;
    UConverter *defConverter = u_getDefaultConverter(&status);
    
    if(U_FAILURE(status) || defConverter == 0)
        return 0;

    if(sSize <= 0) {
        sSize = uprv_strlen(s) + 1;
    }
    
    /* perform the conversion in one swoop */
    if(target != 0) {
        
        alias = target;
        ucnv_toUnicode(defConverter, &alias, alias + tSize, &s, s + sSize - 1, 
            NULL, TRUE, &status);
        
        
        /* add the null terminator */
        *alias = 0x0000;
    }
    
    u_releaseDefaultConverter(defConverter);
    
    return target;
}