xbot/watchdog_thread.hpp

#pragma once

#include <boost/asio/steady_timer.hpp>

#include <chrono>
#include <memory>

class Connection;

/**
 * @brief Watch for connection activity and disconnect on stall
 * 
 * The thread will send a ping if no message is received in the
 * last TIMEOUT seconds. After another period of no messages
 * the thread will disconnect the connection.
 * 
 */
class WatchdogThread : std::enable_shared_from_this<WatchdogThread>
{
    Connection& connection_;
    boost::asio::steady_timer timer_;

    /// @brief Set true and ping sent and false when reply received
    bool stalled_;

    const std::chrono::steady_clock::duration TIMEOUT = std::chrono::seconds{30};

    /// @brief Start the timer
    /// @return 
    auto start_timer();

    /// @brief 
    auto on_activity() -> void;

    /// @brief 
    auto on_timeout() -> void;

    /// @brief callback for ConnectEvent event
    auto on_connect() -> void;

    /// @brief callback for DisconnectEvent event
    auto on_disconnect() -> void;

public:
    WatchdogThread(Connection& connection);
    static auto start(Connection& connection) -> void;
};