chargeBeam.js

function chargeBeam(key, onCharging, onCharged, onCancel, onShoot){
  var chargingTimer;
  var cleared = true;

  function cancelCharge(){
    if (!cleared) {
      clearTimeout(chargingTimer);
      cleared = true;
      onCancel && onCancel();
    }
  }

  function shootChargeBean() {
    document.removeEventListener('keyup', shootChargeBean)
    onShoot && onShoot();
    cleared = true;
  }

  document.addEventListener('keydown', function(e) {
    if (e.keyCode === key && cleared) {
      clearTimeout(chargingTimer);

      chargingTimer = setTimeout(function(){
        onCharged && onCharged();
        document.removeEventListener('keyup', cancelCharge)
        document.addEventListener('keyup', shootChargeBean)
      }, 2000)

      onCharging && onCharging();
      cleared = false;

      document.addEventListener('keyup', cancelCharge)
    }
  })
}

chargeBeam(65,
  function onCharging(){ console.log("Charging..") },
  function onCharged(){ console.log("Charged!") },
  function onCancel(){ console.log("Charge Canceled") },
  function onShoot(){ console.log("WOOOOOOOOOOSH") }
);