getting mousemove direction for custom cursor

mouse-trace.js

//TODO: add cursor bg and rotate script. can't tell what's happening without visual

let lastCoords = [];

const handleDir = e => {
		let xDiff, yDiff, currCoords = [e.x, e.y];
		if ( lastCoords.length !== 0 ){
			xDiff = currCoords[0] - lastCoords[0];
			yDiff = currCoords[1] - lastCoords[1];
		}
		lastCoords = currCoords;		
		let rads = yDiff > 0 ? Math.atan(xDiff/yDiff) : yDiff < 0 ? Math.atan(yDiff/xDiff) : null;
		let degrees = typeof rads !== 'null' ? (rads*(180/Math.PI)) : 'no dice';
		console.log(`Angle: ${degrees}`);
	
}

document.addEventListener('mousemove', handleDir);