openlayers - Creating rectangle on centroid point by map click event ol5

I am trying to develop a web portal using ol5 API where user click on map and then it takes map click event coordinates as centroid of rectangle and create a rectangle of particular height and width.

Here is the code to create square

image: new ol.style.RegularShape({
        fill: fill,

        points: 4,
        radius: 30,
        angle: Math.PI / 4
    })

But I want to create rectangle with center point, height and width. How to achieve this?