Runtime is not defined error

// Import any other script files here, e.g.:
// import * as myModule from "./mymodule.js";

function getRuntime(runtime) {
	return runtime;
}

import animate_playbackState from "./animate.js";
import animate_directionalState from "./animate.js";

// Global variables
var playerInstance = getRuntime(runtime).objects.iPlayer.getFirstInstance();

runOnStartup(async runtime =>
{
	// Code to run on the loading screen.
	// Note layouts, objects etc. are not yet available.
	
	runtime.addEventListener("beforeprojectstart", () => OnBeforeProjectStart(runtime));
});

async function OnBeforeProjectStart(runtime)
{
	// Code to run just before 'On start of layout' on
	// the first layout. Loading has finished and initial
	// instances are created and available to use here.
	
	runtime.addEventListener("tick", () => Tick(runtime));
}

function Tick(runtime) {
	// Animate.js
	if (animate_playbackState) {
		switch (animate_directionalState) {
			case 'up':
				playerInstance.angle = 270;
			case 'down':
				playerInstance.angle = 90;
			case 'left':
				playerInstance.angle = 180;
			case 'right':
				playerInstance.angle = 0;
		}
	}
}