#pragma once

#include <memory>

#include "envoy/common/pure.h"

#include "envoy/common/random_generator.h"

#include "source/common/common/macros.h"

#include "absl/strings/string_view.h"

namespace Envoy {

namespace Extensions {

namespace Tracers {

namespace XRay {

struct SamplingRequest {

  absl::string_view host_;

  absl::string_view http_method_;

  absl::string_view http_url_;

};

/**

 * Strategy provides an interface for implementing trace sampling strategies.

 */

class SamplingStrategy {

public:

  /**

   * sampleRequest determines if the given request should be traced or not.

   * Implementation _must_ be thread-safe.

   */

  virtual bool shouldTrace(const SamplingRequest& sampling_request) PURE;

protected:

private:

  Random::RandomGenerator& rng_;

};

using SamplingStrategyPtr = std::unique_ptr<SamplingStrategy>;

} // namespace XRay

} // namespace Tracers

} // namespace Extensions

} // namespace Envoy