Update an OpenLayers map with markers

map.component.ts

private setupMap(input: MapInput) {
    this.positions = input.markerPosisitons;
    this.userPos = input.userPos;

    if (!this.map) {
        this.initilizeMap();
    }

    const view = this.map.getView();
    if (this.positions.length > 0) {
        view.setCenter(fromLonLat([this.positions[0].lng, this.positions[0].lat]));
    } else if (this.userPos && this.userPos.lat && this.userPos.lng) {
        view.setCenter(fromLonLat([this.userPos.lng, this.userPos.lat]));
    }

    const zoomLevel =
        this.positions.length < 2 ? MapComponent.ZoomLevelSingleMarker : MapComponent.ZoomLevelSeveralMarkers;
    view.setZoom(zoomLevel);

    this.updateMarkers(this.positions, true);
    this.updateUserMarker(this.userPos);
}