#pragma once

#include <string>

#include "envoy/stats/primitive_stats.h"

#include "envoy/upstream/load_balancer.h"

#include "envoy/upstream/upstream.h"

namespace Envoy {

namespace Upstream {

using CommonLbConfigProto = envoy::config::cluster::v3::Cluster::CommonLbConfig;

/**

 * Utility functions for hosts.

 */

class HostUtility {

public:

  using HostStatusSet = std::bitset<32>;

  /**

   * Convert a host's health flags into a debug string.

   */

  static std::string healthFlagsToString(const Host& host);

  // A utility function to create override host status from lb config.

  static HostStatusSet createOverrideHostStatus(const CommonLbConfigProto& common_config);

  /**

   * A utility function to select override host from host map according to load balancer context.

   *

   * @return pair<HostConstSharedPtr, bool> the first element is the selected host and the second

   *         element is a boolean indicating whether the host should be selected strictly or not.

   */

  static std::pair<HostConstSharedPtr, bool>

  selectOverrideHost(const HostMap* host_map, HostStatusSet status, LoadBalancerContext* context);

  // Iterate over all per-endpoint metrics, for clusters with `per_endpoint_stats` enabled.

  static void

  forEachHostMetric(const ClusterManager& cluster_manager,

                    const std::function<void(Stats::PrimitiveCounterSnapshot&& metric)>& counter_cb,

                    const std::function<void(Stats::PrimitiveGaugeSnapshot&& metric)>& gauge_cb);

};

} // namespace Upstream

} // namespace Envoy