#pragma once

/*

 * This file contains implementations of the datadog::tracing::DictReader and

 * datadog::tracing::DictWriter interfaces.

 *

 * The Datadog core tracing library, dd-trace-cpp, uses these interfaces

 * anywhere it needs to read from or write to mappings of string, such as when

 * extracting trace context, injecting trace context, reading HTTP response

 * headers, or writing HTTP request headers.

 */

#include <string>

#include "datadog/dict_reader.h"

#include "datadog/dict_writer.h"

namespace Envoy {

namespace Tracing {

class TraceContext;

} // namespace Tracing

namespace Http {

class RequestHeaderMap;

class ResponseHeaderMap;

} // namespace Http

namespace Extensions {

namespace Tracers {

namespace Datadog {

class RequestHeaderWriter : public datadog::tracing::DictWriter {

public:

  explicit RequestHeaderWriter(Http::RequestHeaderMap& headers);

  void set(datadog::tracing::StringView key, datadog::tracing::StringView value) override;

private:

  Http::RequestHeaderMap& headers_;

};

class ResponseHeaderReader : public datadog::tracing::DictReader {

public:

  explicit ResponseHeaderReader(const Http::ResponseHeaderMap& headers);

  datadog::tracing::Optional<datadog::tracing::StringView>

  lookup(datadog::tracing::StringView key) const override;

  void visit(const std::function<void(datadog::tracing::StringView key,

                                      datadog::tracing::StringView value)>& visitor) const override;

private:

  const Http::ResponseHeaderMap& headers_;

  mutable std::string buffer_;

};

class TraceContextReader : public datadog::tracing::DictReader {

public:

  explicit TraceContextReader(const Tracing::TraceContext& context);

  datadog::tracing::Optional<datadog::tracing::StringView>

  lookup(datadog::tracing::StringView key) const override;

  void visit(const std::function<void(datadog::tracing::StringView key,

                                      datadog::tracing::StringView value)>& visitor) const override;

private:

  const Tracing::TraceContext& context_;

};

} // namespace Datadog

} // namespace Tracers

} // namespace Extensions

} // namespace Envoy