// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

/** @file base64.h
*    @brief Prototypes for functions related to encoding/decoding
*    a @c buffer using standard base64 encoding.
*/

#ifndef BASE64_H
#define BASE64_H

#include "azure_c_shared_utility/strings.h"
#include "azure_c_shared_utility/buffer_.h"

#ifdef __cplusplus
#include <cstddef>
extern "C" {
#else
#include <stddef.h>
#endif

#include "azure_c_shared_utility/umock_c_prod.h"


/**
 * @brief    Base64 encodes a buffer and returns the resulting string.
 *
 * @param    input    The buffer that needs to be base64 encoded.
 *
 *             Base64_Encode takes as a parameter a pointer to a BUFFER. If @p input is @c NULL then
 *             @c Base64_Encode returns @c NULL. The size of the BUFFER pointed to by @p input may
 *             be zero. If when allocating memory to produce the encoding a failure occurs, then @c
 *             Base64_Encode returns @c NULL. Otherwise
 *             @c Base64_Encode returns a pointer to a STRING. That string contains the
 *             base 64 encoding of the @p input. This encoding of @p input will not contain embedded
 *             line feeds.
 *
 * @return    A @c STRING_HANDLE containing the base64 encoding of @p input.
 */
MOCKABLE_FUNCTION(, STRING_HANDLE, Azure_Base64_Encode, BUFFER_HANDLE, input);

/**
 * @brief    Base64 encodes the buffer pointed to by @p source and returns the resulting string.
 *
 * @param    source    The buffer that needs to be base64 encoded.
 * @param    size      The size.
 *
 *             This function produces a @c STRING_HANDLE containing the base64 encoding of the
 *             buffer pointed to by @p source, having the size as given by
 *             @p size. If @p source is @c NULL then @c Base64_Encode_Bytes returns @c NULL
 *             If @p source is not @c NULL and @p size is zero, then @c Base64_Encode_Bytes produces
 *             an empty @c STRING_HANDLE. Otherwise, @c Base64_Encode_Bytes produces a
 *             @c STRING_HANDLE containing the Base64 representation of the buffer. In case of
 *             any errors, @c Base64_Encode_Bytes returns @c NULL.].
 *
 * @return    @c NULL in case an error occurs or a @c STRING_HANDLE containing the base64 encoding
 *             of @p input.
 *
 */
MOCKABLE_FUNCTION(, STRING_HANDLE, Azure_Base64_Encode_Bytes, const unsigned char*, source, size_t, size);

/**
 * @brief    Base64 decodes the buffer pointed to by @p source and returns the resulting buffer.
 *
 * @param    source    A base64 encoded string buffer.
 *
 *           This function decodes the string pointed at by @p source using base64 decoding and
 *             returns the resulting buffer. If @p source is @c NULL then
 *             @c Azure_Base64_Decode returns NULL. If the string pointed to by @p source is zero
 *             length then the handle returned refers to a zero length buffer. If there is any
 *             memory allocation failure during the decode or if the source string has an invalid
 *             length for a base 64 encoded string then @c Azure_Base64_Decode returns @c NULL.
 *
 * @return    A @c BUFFER_HANDLE pointing to a buffer containing the result of base64 decoding @p
 *             source.
 */
MOCKABLE_FUNCTION(, BUFFER_HANDLE, Azure_Base64_Decode, const char*, source);

#ifdef __cplusplus
}
#endif

#endif /* BASE64_H */