/*

 * Copyright (c) 2014-2020 Pavel Kalvoda <me@pavelkalvoda.com>

 *

 * libcbor is free software; you can redistribute it and/or modify

 * it under the terms of the MIT license. See LICENSE for details.

 */

#include "encoders.h"

#include <string.h>

size_t _cbor_encode_uint8(uint8_t value, unsigned char *buffer,

                          size_t buffer_size, uint8_t offset) {

  if (value <= 23) {

    if (buffer_size >= 1) {

      buffer[0] = value + offset;

      return 1;

    }

  } else {

    if (buffer_size >= 2) {

      buffer[0] = 0x18 + offset;

      buffer[1] = value;

      return 2;

    }

  }

  return 0;

}

size_t _cbor_encode_uint16(uint16_t value, unsigned char *buffer,

                           size_t buffer_size, uint8_t offset) {

  if (buffer_size >= 3) {

    buffer[0] = 0x19 + offset;

#ifdef IS_BIG_ENDIAN

    memcpy(buffer + 1, &value, 2);

#else

    buffer[1] = (unsigned char)(value >> 8);

    buffer[2] = (unsigned char)value;

#endif

    return 3;

  } else

    return 0;

}

size_t _cbor_encode_uint32(uint32_t value, unsigned char *buffer,

                           size_t buffer_size, uint8_t offset) {

  if (buffer_size >= 5) {

    buffer[0] = 0x1A + offset;

#ifdef IS_BIG_ENDIAN

    memcpy(buffer + 1, &value, 4);

#else

    buffer[1] = (unsigned char)(value >> 24);

    buffer[2] = (unsigned char)(value >> 16);

    buffer[3] = (unsigned char)(value >> 8);

    buffer[4] = (unsigned char)value;

#endif

    return 5;

  } else

    return 0;

}

size_t _cbor_encode_uint64(uint64_t value, unsigned char *buffer,

                           size_t buffer_size, uint8_t offset) {

  if (buffer_size >= 9) {

    buffer[0] = 0x1B + offset;

#ifdef IS_BIG_ENDIAN

    memcpy(buffer + 1, &value, 8);

#else

    buffer[1] = (unsigned char)(value >> 56);

    buffer[2] = (unsigned char)(value >> 48);

    buffer[3] = (unsigned char)(value >> 40);

    buffer[4] = (unsigned char)(value >> 32);

    buffer[5] = (unsigned char)(value >> 24);

    buffer[6] = (unsigned char)(value >> 16);

    buffer[7] = (unsigned char)(value >> 8);

    buffer[8] = (unsigned char)value;

#endif

    return 9;

  } else

    return 0;

}

size_t _cbor_encode_uint(uint64_t value, unsigned char *buffer,

                         size_t buffer_size, uint8_t offset) {

  if (value <= UINT16_MAX)

    if (value <= UINT8_MAX)

      return _cbor_encode_uint8((uint8_t)value, buffer, buffer_size, offset);

    else

      return _cbor_encode_uint16((uint16_t)value, buffer, buffer_size, offset);

  else if (value <= UINT32_MAX)

    return _cbor_encode_uint32((uint32_t)value, buffer, buffer_size, offset);

  else

    return _cbor_encode_uint64((uint64_t)value, buffer, buffer_size, offset);

}