/* A simple buffer for encoding streamed JSON messages.
 *
 * Author: Steffen Vogel <post@steffenvogel.de>
 * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
 * SPDX-License-Identifier: Apache-2.0
 */

#include <villas/buffer.hpp>
#include <villas/compat.hpp>

using namespace villas;

json_t *Buffer::decode() {
  json_t *j;
  json_error_t err;

  j = json_loadb(data(), size(), JSON_DISABLE_EOF_CHECK, &err);
  if (!j)
    return nullptr;

  // Remove decoded JSON document from beginning
  erase(begin(), begin() + err.position);

  return j;
}

int Buffer::encode(json_t *j, int flags) {
  return json_dump_callback(j, callback, this, flags);
}

int Buffer::callback(const char *data, size_t len, void *ctx) {
  Buffer *b = static_cast<Buffer *>(ctx);

  // Append junk of JSON to buffer
  b->insert(b->end(), &data[0], &data[len]);

  return 0;
}