xbot/watchdog_thread.cpp

#include "watchdog_thread.hpp"

#include "connection.hpp"
#include "irc_parse_thread.hpp"
#include "write_irc.hpp"

#include <boost/asio/steady_timer.hpp>

#include <chrono>
#include <memory>

using namespace std::chrono_literals;

namespace {

struct WatchdogThread : std::enable_shared_from_this<WatchdogThread>
{
    WatchdogThread(Connection& connection)
    : connection_{connection}
    , timer_{connection.get_executor()}
    , tried_ping{false}
    {
    }

    Connection& connection_;
    boost::asio::steady_timer timer_;
    bool tried_ping;

    auto on_activity() -> void
    {
        tried_ping = false;
        timer_.expires_from_now(30s);
    }

    auto timeout_token() 
    {
        return [weak = weak_from_this()](auto const& error)
        {
            if (not error)
            {
                if (auto self = weak.lock())
                {
                    self->on_timeout();
                }
            }
        };
    }

    auto on_timeout() -> void
    {
        if (tried_ping)
        {
            connection_.close();
        }
        else
        {
            send_ping(connection_, "watchdog");
            tried_ping = true;
            timer_.expires_from_now(30s);
            timer_.async_wait(timeout_token());
        }
    }

    auto on_connect() -> void
    {
        on_activity();
        timer_.async_wait(timeout_token());
    }

    auto on_disconnect() -> void
    {
        timer_.cancel();
    }
};

} // namespace

auto watchdog_thread(Connection& connection) -> void
{
    auto const thread = std::make_shared<WatchdogThread>(connection);
    connection.add_listener<ConnectEvent>([thread](auto&)
    {
        thread->on_connect();
    });
    connection.add_listener<DisconnectEvent>([thread](auto&)
    {
        thread->on_disconnect();
    });
    connection.add_listener<IrcMsgEvent>([thread](auto&)
    {
        thread->on_activity();
    });
}