State get_state() const { return state; }
const Msp::Time::TimeDelta &get_duration() const { return duration; }
const Msp::Time::TimeDelta &get_position() const { return position; }
State get_state() const { return state; }
const Msp::Time::TimeDelta &get_duration() const { return duration; }
const Msp::Time::TimeDelta &get_position() const { return position; }