/*

 * Copyright 2017 Techie Delight

 * Permission is hereby granted, free of charge, to any person obtaining a copy 

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights 

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 

 * copies of the Software, and to permit persons to whom the Software is 

 * furnished to do so, subject to the following conditions:

 * 

 * The above copyright notice and this permission notice shall be included 

 * in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 

 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF 

 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 */

/* Originally released by techiedelight.com 

 * (http://www.techiedelight.com/implement-itoa-function-in-c/) under the

 * MIT license. */

#include "itoa.h"

static void swap(char *x, char *y) {

    char t = *x;

    *x = *y;

    *y = t;

}

/* function to reverse buffer */

static char* reverse(char *buffer, UA_UInt16 i, UA_UInt16 j) {

    while (i < j)

        swap(&buffer[i++], &buffer[j--]);

    return buffer;

}

/* adapted from http://www.techiedelight.com/implement-itoa-function-in-c/ to use UA_... types */

UA_UInt16 itoaUnsigned(UA_UInt64 value, char* buffer, UA_Byte base) {

    /* consider absolute value of number */

    UA_UInt64 n = value;

    UA_UInt16 i = 0;

    while (n) {

        UA_UInt64 r = n % base;

        if (r >= 10)

            buffer[i++] = (char)(65 + (r - 10));

        else

            buffer[i++] = (char)(48 + r);

        n = n / base;

    }

    /* if number is 0 */

    if (i == 0)

        buffer[i++] = '0';

    buffer[i] = '\0'; /* null terminate string */

    i--;

    /* reverse the string */

    reverse(buffer, 0, i);

    i++;

    return i;

}

/* adapted from http://www.techiedelight.com/implement-itoa-function-in-c/ to use UA_... types */

UA_UInt16 itoaSigned(UA_Int64 value, char* buffer) {

    /* consider absolute value of number */

    UA_UInt64 n;

    /* Special case for UA_INT64_MIN which can not simply be negated */

    /* it will cause a signed integer overflow */

    if (value == UA_INT64_MIN) {

        n = (UA_UInt64)UA_INT64_MAX + 1;

    }

    else {

        n = (UA_UInt64)value;

        if(value < 0){

            n = (UA_UInt64)-value;

        }

    }

    UA_UInt16 i = 0;

    while (n) {

        UA_UInt64 r = n % 10;

        if (r >= 10)

            buffer[i++] = (char)(65 + (r - 10));

        else

            buffer[i++] = (char)(48 + r);

        n = n / 10;

    }

    /* if number is 0 */

    if (i == 0)

        buffer[i++] = '0';

    if (value < 0)

        buffer[i++] = '-';

    buffer[i] = '\0'; /* null terminate string */

    i--;

    /* reverse the string and return it */

    reverse(buffer, 0, i);

    i++;

    return i;

}