//
//
// Copyright 2018 gRPC authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//

#ifndef GRPC_SRC_CORE_LIB_RESOLVER_SERVER_ADDRESS_H
#define GRPC_SRC_CORE_LIB_RESOLVER_SERVER_ADDRESS_H

#include <grpc/support/port_platform.h>

#include <string>
#include <vector>

#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/iomgr/resolved_address.h"

// A channel arg key prefix used for args that are intended to be used
// only internally to resolvers and LB policies and should not be part
// of the subchannel key.  The channel will automatically filter out any
// args with this prefix from the subchannel's args.
#define GRPC_ARG_NO_SUBCHANNEL_PREFIX "grpc.internal.no_subchannel."

// A channel arg indicating the weight of an address.
#define GRPC_ARG_ADDRESS_WEIGHT GRPC_ARG_NO_SUBCHANNEL_PREFIX "address.weight"

namespace grpc_core {

//
// ServerAddress
//

// A server address is a grpc_resolved_address with an associated set of
// channel args.  Any args present here will be merged into the channel
// args when a subchannel is created for this address.
class ServerAddress {
 public:
  ServerAddress(const grpc_resolved_address& address, const ChannelArgs& args);

  // Copyable.
  ServerAddress(const ServerAddress& other);
  ServerAddress& operator=(const ServerAddress& other);

  // Movable.
  ServerAddress(ServerAddress&& other) noexcept;
  ServerAddress& operator=(ServerAddress&& other) noexcept;

  bool operator==(const ServerAddress& other) const { return Cmp(other) == 0; }
  bool operator<(const ServerAddress& other) const { return Cmp(other) < 0; }

  int Cmp(const ServerAddress& other) const;

  const grpc_resolved_address& address() const { return address_; }
  const ChannelArgs& args() const { return args_; }

  // TODO(ctiller): Prior to making this a public API we should ensure that the
  // channel args are not part of the generated string, lest we make that debug
  // format load-bearing via Hyrum's law.
  std::string ToString() const;

 private:
  grpc_resolved_address address_;
  ChannelArgs args_;
};

//
// ServerAddressList
//

using ServerAddressList = std::vector<ServerAddress>;

}  // namespace grpc_core

#endif  // GRPC_SRC_CORE_LIB_RESOLVER_SERVER_ADDRESS_H