// function popupWindow()
// function:    To open a popup window with parent/child ability.
// parameters:  urlStr- the URL of the file to load into the popup window (string)
//              childWindow- object reference to the popup window (string)
//              windowName- a string reference to the popup window (string)
//              W- the width in pixels
//              H- the height in pixels
//              T- boolean flag to display the toolbar ('yes' or 'no')
//              L- boolean flag to display the location field
//              M- boolean flag to display the menubar
//              S- boolean flag to display the scrollbars
//              R- boolean flag to allow the popup to be resized
//              ST- boolean flag to display the status bar
//              webtvPage- boolean flag for whether or not there should be an in-line
//                         version of the page instead of a popup for webtv users ('yes' or 'no')
//              webtvMsg- message that appears in the status bar if no in-line page
//                        version of the popup for webtv users (string)

function popupWindow(urlStr, childWindow, windowName, W, H, T, L, M, S, R, ST, webtvPage, webtvMsg) {   
   if (navigator.appVersion.indexOf("WebTV") != -1) {
      if (webtvPage) {
         window.location = urlStr;
      } else {
         window.status = webtvMsg; 
      }		 
   } else {
      windowFeature = "width=" + W + ",height=" + H + ",toolbar=" + T + ",location=" + L + ",menubar=" + M + ",scrollbars=" + S + ",resizable=" + R + ",status=" + ST;
      childWindow = new Object();
	  childWindow = window.open(urlStr, windowName, windowFeature);
      childWindow.focus();  
	  if ((navigator.appName=="Microsoft Internet Explorer") && (parseInt(navigator.appVersion) < 4)) { // IE3 does not support parent/child browser relationships
      } else {
         childWindow.opener = self.parent;
      }
   }   
   return childWindow;
}

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

// store variables to control where the popup will appear relative to the cursor position
// positive numbers are below and to the right of the cursor, negative numbers are above and to the left
var xOffset = 30;
var yOffset = -5;

function showPopup (targetObjectId, eventObj) {
	var IfrRef = document.getElementById("ifrm_"+targetObjectId);
	var DivRef = document.getElementById(targetObjectId);
    if(eventObj) {
	// hide any currently-visible popups
	hideCurrentPopup();
	// 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)
	var newXCoordinate = (eventObj.pageX)?eventObj.pageX + xOffset:eventObj.x + xOffset + ((document.body.scrollLeft)?document.body.scrollLeft:0);
	var newYCoordinate = (eventObj.pageY)?eventObj.pageY + yOffset:eventObj.y + yOffset + ((document.body.scrollTop)?document.body.scrollTop:0);
	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;
		if(IfrRef!=null && IfrRef!= 'undefined'){
		IfrRef.style.width = DivRef.offsetWidth;	
		IfrRef.style.height = DivRef.offsetHeight;		
		IfrRef.style.top = DivRef.style.top;		
		IfrRef.style.left = DivRef.style.left;
		IfrRef.style.zIndex = DivRef.style.zIndex - 1;		
		IfrRef.style.display = "block";				
		}	
	    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(targetObjectId) {
	var IfrRef = document.getElementById("ifrm_"+targetObjectId);
    // note: we've stored the currently-visible popup on the global object window.currentlyVisiblePopup
	if(window.currentlyVisiblePopup!='undefined' && window.currentlyVisiblePopup) {	
			changeObjectVisibility(window.currentlyVisiblePopup, 'hidden');
			window.currentlyVisiblePopup = false;
			if(IfrRef!=null && IfrRef!='undefined'){
				IfrRef.style.display = "none";
			}		
	}
} // hideCurrentPopup