platform/api/connection.h

// Copyright 2026 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef PLATFORM_API_CONNECTION_H_
#define PLATFORM_API_CONNECTION_H_

#include <cstdint>
#include <vector>

#include "platform/base/error.h"
#include "platform/base/ip_address.h"
#include "platform/base/span.h"

namespace openscreen {

// Represents a connection between two endpoints. This class provides an
// interface for sending and receiving byte data over a connection.
class Connection {
 public:
  // Client callbacks are run via the TaskRunner used by TlsConnectionFactory.
  class Client {
   public:
    // Called when `connection` experiences an error, such as a read error.
    virtual void OnError(Connection* connection, const Error& error) = 0;

    // Called when a `block` arrives on `connection`.
    virtual void OnRead(Connection* connection, std::vector<uint8_t> block) = 0;

   protected:
    virtual ~Client() = default;
  };

  virtual ~Connection() = default;

  // Sets the Client associated with this instance. This should be called as
  // soon as the factory provides a new Connection instance via
  // TlsConnectionFactory::OnAccepted(), OnConnected() or CreateSocket().
  // Pass nullptr to unset the Client.
  virtual void SetClient(Client* client) = 0;

  // Sends a message. Returns true iff the message will be sent.
  [[nodiscard]] virtual bool Send(ByteView data) = 0;

  // Get the connected remote address.
  virtual IPEndpoint GetRemoteEndpoint() const = 0;

 protected:
  Connection() = default;
};

}  // namespace openscreen

#endif  // PLATFORM_API_CONNECTION_H_