function getStyleObject(objectId) {
    // cross-browser function to get an object's style object given its id
    if(document.getElementById && document.getElementById(objectId)) {
	// W3C DOM
	return document.getElementById(objectId).style;
    } else if (document.all && document.all(objectId)) {
	// MSIE 4 DOM
	return document.all(objectId).style;
    } else if (document.layers && document.layers[objectId]) {
	// NN 4 DOM.. note: this won't find nested layers
	return document.layers[objectId];
    } else {
	return false;
    }
} // getStyleObject

function changeObjectVisibility(objectId, newVisibility) {   
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
	styleObject.visibility = newVisibility;
	return true;
    } else {
	// we couldn't find the object, so we can't change its visibility
	return false;
    }
} // changeObjectVisibility

function moveObject(objectId, newXCoordinate, newYCoordinate) {
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
	styleObject.left = newXCoordinate;
	styleObject.top = newYCoordinate;
	return true;
    } else {
	// we couldn't find the object, so we can't very well move it
	return false;
    }
} // moveObject

var xOffset = -200;
var yOffset = -5;

function showPopup (targetObjectId, eventObj) {
    if(eventObj) {
	
		// stop event from bubbling up any farther
		eventObj.cancelBubble = true;
		// move popup div to current cursor position 
		// (add scrollTop to account for scrolling for IE)
		
		newXCoordinate = myMouseX;
		newYCoordinate = myMouseY;
		moveObject(targetObjectId, newXCoordinate, newYCoordinate);
		// and make it visible
		if( changeObjectVisibility(targetObjectId, 'visible') ) {
		    // if we successfully showed the popup
		    // store its Id on a globally-accessible object
		    window.currentlyVisiblePopup = targetObjectId;
		    return true;
		} 
		else {
		    // we couldn't show the popup, boo hoo!
		    return false;
		}
	 } 
	 else 
	 {		// there was no event object, so we won't be able to position anything, so give up
			return false;
     }
} // showPopup

function hideCurrentPopup() {
    // note: we've stored the currently-visible popup on the global object window.currentlyVisiblePopup
    if(window.currentlyVisiblePopup) {
	changeObjectVisibility(window.currentlyVisiblePopup, 'hidden');
	window.currentlyVisiblePopup = false;
    }
} // hideCurrentPopup

window.onload = initializeHacks;
document.onclick = hideCurrentPopup;

function initializeHacks() {
    // this ugly little hack resizes a blank div to make sure you can click
    // anywhere in the window for Mac MSIE 5
    if ((navigator.appVersion.indexOf('MSIE 5') != -1) 
	&& (navigator.platform.indexOf('Mac') != -1)
	&& getStyleObject('blankDiv')) {
	window.onresize = explorerMacResizeFix;
    }
    resizeBlankDiv();
    // this next function creates a placeholder object for older browsers
    createFakeEventObj();
}

function createFakeEventObj() {
    // create a fake event object for older browsers to avoid errors in function call
    // when we need to pass the event object to functions
    if (!window.event) {
	window.event = false;
    }
} // createFakeEventObj

function resizeBlankDiv() {
    // resize blank placeholder div so IE 5 on mac will get all clicks in window
    if ((navigator.appVersion.indexOf('MSIE 5') != -1) 
	&& (navigator.platform.indexOf('Mac') != -1)
	&& getStyleObject('blankDiv')) {
	getStyleObject('blankDiv').width = document.body.clientWidth - 20;
	getStyleObject('blankDiv').height = document.body.clientHeight - 20;
    }
}

function explorerMacResizeFix () {
    location.reload(false);
}
