// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_SOCKET_TRANSPORT_CONNECT_SUB_JOB_H_
#define NET_SOCKET_TRANSPORT_CONNECT_SUB_JOB_H_

#include <stddef.h>

#include <memory>
#include <utility>
#include <vector>

#include "base/memory/raw_ptr.h"
#include "net/base/address_list.h"
#include "net/base/load_states.h"
#include "net/socket/transport_connect_job.h"
#include "net/socket/websocket_endpoint_lock_manager.h"

namespace net {

class IPEndPoint;
class StreamSocket;

// Attempts to connect to a subset of the addresses required by a
// TransportConnectJob, specifically either the IPv4 or IPv6 addresses. Each
// address is tried in turn, and parent_job->OnSubJobComplete() is called when
// the first address succeeds or the last address fails.
class TransportConnectSubJob : public WebSocketEndpointLockManager::Waiter {
 public:
  using SubJobType = TransportConnectJob::SubJobType;

  TransportConnectSubJob(std::vector<IPEndPoint> addresses,
                         TransportConnectJob* parent_job,
                         SubJobType type);

  TransportConnectSubJob(const TransportConnectSubJob&) = delete;
  TransportConnectSubJob& operator=(const TransportConnectSubJob&) = delete;

  ~TransportConnectSubJob() override;

  // Start connecting.
  int Start();

  bool started() { return next_state_ != STATE_NONE; }

  LoadState GetLoadState() const;

  SubJobType type() const { return type_; }

  std::unique_ptr<StreamSocket> PassSocket() {
    return std::move(transport_socket_);
  }

  // Implementation of WebSocketEndpointLockManager::EndpointWaiter.
  void GotEndpointLock() override;

 private:
  enum State {
    STATE_NONE,
    STATE_OBTAIN_LOCK,
    STATE_OBTAIN_LOCK_COMPLETE,
    STATE_TRANSPORT_CONNECT_COMPLETE,
    STATE_DONE,
  };

  const IPEndPoint& CurrentAddress() const;

  void OnIOComplete(int result);
  int DoLoop(int result);
  int DoEndpointLock();
  int DoEndpointLockComplete();
  int DoTransportConnectComplete(int result);

  const raw_ptr<TransportConnectJob> parent_job_;

  std::vector<IPEndPoint> addresses_;
  size_t current_address_index_ = 0;

  State next_state_ = STATE_NONE;
  const SubJobType type_;

  std::unique_ptr<StreamSocket> transport_socket_;
};

}  // namespace net

#endif  // NET_SOCKET_TRANSPORT_CONNECT_SUB_JOB_H_