import { SyntheticWheelEvent } from '../../SyntheticWheelEvent';
import { NativeMouseEvent } from './NativeMouseEvent';

// @ts-ignore: https://github.com/Microsoft/TypeScript/issues/4628
export class NativeWheelEvent extends NativeMouseEvent {
    //! \see http://stackoverflow.com/questions/5527601/normalizing-mousewheel-speed-across-browsers
    static normalizeDelta(e: any, delta: number) {
        return e.deltaMode === 1 ? delta * 40 :
            e.deltaMode === 2 ? delta * 800 : delta;
    }

    static map(e: any) {
        const ret = new SyntheticWheelEvent();
        NativeMouseEvent.init(e, ret);
        ret.deltaX = NativeWheelEvent.normalizeDelta(e, e.deltaX === undefined ? 0 : e.deltaX);
        ret.deltaY = NativeWheelEvent.normalizeDelta(e, e.deltaY === undefined ? e.wheelDelta : e.deltaY);
        return ret;
    }

    static readonly target = SyntheticWheelEvent;
}