사용자 정의 가능한 옵션을 사용하여 JavaScript에서 마우스 클릭을 어떻게 시뮬레이션할 수 있습니까?

function contextMenuClick()
{
  var element= 'button';
  var evt = element.ownerDocument.createEvent('MouseEvents');

  evt.initMouseEvent('contextmenu', true, true, element.ownerDocument.defaultView,
                     1, 0, 0, 0, 0, false, false, false, false, 1, null);

  element.dispatchEvent(evt);
}

function simulate(element, eventName, options)
{
    // Set default options
    var defaultOptions = {
        pointerX: 0,
        pointerY: 0,
        button: 0,
        ctrlKey: false,
        altKey: false,
        shiftKey: false,
        metaKey: false,
        bubbles: true,
        cancelable: true
    };

    // Extend default options with provided options
    for (var property in options)
      defaultOptions[property] = options[property];

    // Determine event type
    var eventType = null;
    for (var name in eventMatchers)
    {
        if (eventMatchers[name].test(eventName)) { 
            eventType = name; 
            break; 
        }
    }

    // Create and initialize event
    var oEvent;
    if (document.createEvent)
    {
        if (eventType == 'HTMLEvents')
        {
            oEvent = document.createEvent(eventType);
            oEvent.initEvent(eventName, defaultOptions.bubbles, defaultOptions.cancelable);
        }
        else
        {
            oEvent = document.createEvent(eventType);
            oEvent.initMouseEvent(eventName, defaultOptions.bubbles, defaultOptions.cancelable, document.defaultView,
            defaultOptions.button, defaultOptions.pointerX, defaultOptions.pointerY, defaultOptions.pointerX, defaultOptions.pointerY,
            defaultOptions.ctrlKey, defaultOptions.altKey, defaultOptions.shiftKey, defaultOptions.metaKey, defaultOptions.button, element);
        }
        element.dispatchEvent(oEvent);
    }
    else
    {
        // Legacy IE fallback
        defaultOptions.clientX = defaultOptions.pointerX;
        defaultOptions.clientY = defaultOptions.pointerY;
        oEvent = document.createEventObject();
        oEvent = extend(oEvent, defaultOptions);
        element.fireEvent('on' + eventName, oEvent);
    }

    return element;
}

simulate(document.getElementById("btn"), "click", { pointerX: 123, pointerY: 321 });