Creates a new tooltip-like widget using the given options object.

     Options:

     .refresh: callback which is called just before the tooltip is
     revealed or moved. It must refresh the contents of the tooltip,
     if needed, by applying the content to/within this.e, which is the
     base DOM element for the tooltip. If the contents are static and
     set up via the .init option then this callback is not needed.
     base DOM element for the tooltip (and is a child of
     document.body). If the contents are static and set up via the
     .init option then this callback is not needed.

     .adjustX: an optional callback which is called when the tooltip
     is to be displayed at a given position and passed the X
     viewport-relative coordinate. This routine must either return its
     argument as-is or return an adjusted value. The intent is to
     allow a given tooltip may be positioned more appropriately for a
     given context, if needed (noting that the desired position can,

       Returns this object.

       Sidebar: showing/hiding the widget is, as is conventional for
       this framework, done by removing/adding the 'hidden' CSS class
       to it, so that class must be defined appropriately.
    */
    show: function(){
      var x = 0, y = 0, showIt;
      var x = undefined, y = undefined, showIt;
      if(2===arguments.length){
        x = arguments[0];
        y = arguments[1];
        showIt = true;
      }else if(1===arguments.length){
        if(arguments[0] instanceof HTMLElement){
          const p = arguments[0];

      if(showIt){
        this.refresh();
        x = this.options.adjustX.call(this,x);
        y = this.options.adjustY.call(this,y);
        x += window.pageXOffset;
        y += window.pageYOffset;
      }
      D[showIt ? 'removeClass' : 'addClass'](this.e, 'hidden');
      if(x || y){
        this.e.style.left = x+"px";
        this.e.style.top = y+"px";
      }
      console.debug("showIt?",showIt,x,y);
      if(showIt){
        if('number'===typeof x && 'number'===typeof y){
          this.e.style.left = x+"px";
          this.e.style.top = y+"px";
        }
        D.removeClass(this.e, 'hidden');
      }else{
        D.addClass(this.e, 'hidden');
        delete this.e.style.removeProperty('left');
        delete this.e.style.removeProperty('top');
      }
      return this;
    },
    }

    hide: function(){return this.show(false)}
  }/*F.PopupWidget.prototype*/;
  

  /**
     Convenience wrapper around a PopupWidget which pops up a shared
     PopupWidget instance to show toast-style messages (commonly seen
     on Android). Its arguments may be anything suitable for passing
     to fossil.dom.append(), and each argument is first append()ed to
     the toast widget, then the widget is shown for
     F.toast.config.displayTimeMs milliseconds. This is called while
     a toast is currently being displayed, the first will be overwritten
     and the time until the message is hidden will be reset.

     The toast is always shown at the viewport-relative coordinates
     defined by the F.toast.config.position.

     The toaster's DOM element has the CSS classes fossil-tooltip
     and fossil-toast, so can be style via those.
  */
  F.toast = function f(/*...*/){
    if(!f.toast){
      f.toast = function ff(argsObject){
        if(!ff.toaster) ff.toaster = new F.PopupWidget({
          cssClass: ['fossil-tooltip', 'fossil-toast']
        });
        if(f._timer) clearTimeout(f._timer);
        D.clearElement(ff.toaster.e);
        var i = 0;
        for( ; i < argsObject.length; ++i ){
          D.append(ff.toaster.e, argsObject[i]);
        };
        ff.toaster.show(f.config.position.x, f.config.position.y);
        f._timer = setTimeout(()=>ff.toaster.hide(), f.config.displayTimeMs);
      };
    }
    f.toast(arguments);
  };
  F.toast.config = {
    position: { x: 5, y: 5 /*viewport-relative, pixels*/ },
    displayTimeMs: 2500
  };

})(window.fossil);