#pragma once

#include "envoy/formatter/substitution_formatter.h"

#include "envoy/stream_info/stream_info.h"

namespace Envoy {

namespace Extensions {

namespace AccessLoggers {

namespace Fluentd {

/**

 * A formatter for Fluentd logs

 */

class FluentdFormatter {

public:

  /**

   * @return a vector of bytes representing the Fluentd MessagePack record

   */

  virtual std::vector<uint8_t> format(const Formatter::Context& context,

                                      const StreamInfo::StreamInfo& stream_info) const PURE;

};

using FluentdFormatterPtr = std::unique_ptr<FluentdFormatter>;

/**

 * A formatter for Fluentd logs. It is expecting to receive a JSON formatter, and converts the

 * JSON formatter message to MessagePack format.

 * TODO(ohadvano): Improve the formatting operation by creating a dedicated formatter that

 *                 will directly serialize the record to msgpack payload.

 */

class FluentdFormatterImpl : public FluentdFormatter {

public:

  FluentdFormatterImpl(Formatter::FormatterPtr json_formatter);

  std::vector<uint8_t> format(const Formatter::Context& context,

                              const StreamInfo::StreamInfo& stream_info) const override;

private:

  Formatter::FormatterPtr json_formatter_;

};

} // namespace Fluentd

} // namespace AccessLoggers

} // namespace Extensions

} // namespace Envoy