interface IPowerSwitch {
    /* admin events */

    event PowerOn();
    event PowerOff();
    event EmergencyShutdown();

    /* data types */

    enum State {Online, Offline, Shutdown}

    /* admin functions */

    function powerOn() external;

    function powerOff() external;

    function emergencyShutdown() external;

    /* view functions */

    function isOnline() external view returns (bool status);

    function isOffline() external view returns (bool status);

    function isShutdown() external view returns (bool status);

    function getStatus() external view returns (State status);

    function getPowerController() external view returns (address controller);
}
function powerOn() external;

/* admin functions */