/******************************************************************************
*                                                                             *
* This Javascript iterates through the page causing certain links to pop up   *
* windows when clicked. I got much assistance in writing this from            *
* <alistapart.com> and <sitepoint.com>.                                       *
*                                                                             *
* Author:   Michael A. Smith                                                  *
* Modified: 09/10/09                                                          *
*                                                                             *
******************************************************************************/

/** Performs the popUp action */
function popupWin(link, attribs, rel) {
	// rel describes the relationship of the new window
	if (rel == "") rel = "_blank";

	window.open(link, rel, attribs);
} // end popupWin

/** Returns true if the href ends in pdf */
function isSpecialFile(href) {
	href = cleanHashFromURL(href);
	href = cleanParamsFromURL(href);
	var fileExt = getFileExtension(href);

	if (fileExt == "") return false;  // If there's no file extension, bail

	return ((fileExt == "pdf"));
} // end isSpecialFile

/** Gets the file extension. Returns an empty string if unknown. */
function getFileExtension(href) {
	if (href.indexOf(".") < 0) return ""; // If there's no "." in the URL, bail

	var extArray = href.split(".");
	var lastIndex = [extArray.length - 1];
	var ext = extArray[lastIndex];

	// If there's a "/" in the extension, bail
	if (ext.indexOf("/") > -1) return "";

	return ext.split("?")[0]; // If there's a ? in the extension, truncate there
} // end getFileExtension


/** Gets the protocol (http, https, mailto, etc...) */
function getURLProtocol(href) {
	/* Gecko browsers return the actual href attribute. IE and Opera return the
		 calculated complete URL from the protocol on. */
	var prot = href.split(":")[0];

	// if there's a slash or pound in the prot we assume it's http (for geckos)
	if (prot.indexOf("/") > -1) return "http";
	if (prot.indexOf("#") > -1) return "http";

	return prot;
} // end getURLProtocol

/** clean hashes from urls */
function cleanHashFromURL(url) {
	var index = url.indexOf("#");
	if (index < 0) return url;

	return url.substring(0, index);
} // end cleanHashFromURL

/** clean parameters from urls */
function cleanParamsFromURL(url) {
	var index = url.indexOf("?");
	if (index < 0) return url;

	return url.substring(0, index);
} // end cleanParamsFromURL


/** Returns false if the href can be determined to be an external link. */
function isInternal(href) {

	href = cleanHashFromURL(href); // if the URL has a # get rid of it

	// count as internal if there are no "/"s in the URL
	if (href.indexOf("/") < 0) return true;

	// split the URL into an array of strings across the "/" character
	var hrefSplit = href.split("/");

	// if the URL doesn't start with 'http', don't go any further.
	if (!(document.all || window.opera)) {
		if (hrefSplit[0].indexOf("http") < 0) return true;
	}

	// "url" is from the href attribute of the anchor tag
	var url = "";
	if (hrefSplit[2]) url = hrefSplit[2];

	// httpHost is the 2nd string from the window.location.href split across "/"
	var locHrefSplit = window.location.href.split("/");
	var httpHost = "";
	if (locHrefSplit[2]) httpHost = locHrefSplit[2];

	/* Count as internal if the url or the current site url doesn't exist
		 (shouldn't ever happen) */
	if (!(url && httpHost)) return true;

	// check that the current site matches the url
	if (url == httpHost) return true;

	// if the host has the same top two domain levels, it's internal
	hostSplit = httpHost.split('.');
	urlSplit = url.split('.');
	hostTld = hostSplit.pop();
	hostDom = hostSplit.pop();
	urlTld = urlSplit.pop();
	urlDom = urlSplit.pop();

	if (hostTld == urlTld && hostDom == urlDom) return true;
	return false
} // end isInternal


/** determine whether or not the popup should happen */
function isPopUp(rel, href){

	// if the href value is empty or null, don't pop up
	if (!href) return false;

	// if the URL protocol is not http or https, don't popup
	if (getURLProtocol(href).indexOf("http") < 0) return false;

	// if the rel attribute exists and is not a specifically excluded rel, pop up
	if (rel) {
		if ((rel == 'sidebar') || (rel == 'tag')) return false;
		return true;
	}

	// if the link is to an image, pdf, or other special file, pop up
	if (isSpecialFile(href)) {
		return true;
	}

	// if the link is to an external file, pop up
	return (!isInternal(href));
} // isPopUp

/**
  This is the function you call when the page loads. It iterates through the
  page looking for anchor tags to which to attach.
*/
function init_popupwin() {
	/*
		check that the user agent is modern enough to perform necessary
		operations.
	*/
	if(!document.getElementsByTagName) return;

	// get an array of all anchor tags on the page
	var anchors = document.getElementsByTagName("a");
	// loop through all the anchor tags
	for (var i = 0; i < anchors.length; i++) {
		// current anchor
		var anchor = anchors[i];
		// href attribute
		var href = anchor.getAttribute("href");
		// rel attribute
		var rel = anchor.getAttribute("rel");

		// if we shouldn't pop up, go to the next step in the for loop
		if (!isPopUp(rel, href)) continue;

		// at this point we've determined that we should popup the link

		// default window attributes
		var winWidth =      650;
		var winHeight =     350;
		var winLocation =   "yes";
		var winMenubar =    "yes";
		var winStatus =     "yes";
		var winScrollbars = "yes";
		var winResizable =  "yes";
		var winToolbar =    "yes";

		// rel can change the attributes
		// @@@ status bar option not respected by firefox?
		switch (rel) {
			case "sidebar":
				//just in time breakout
				continue;
				break; // end case "sidebar"
			case "tag":
				// just in time breakout
				continue;
				break; // end case "tag"
		} // end switch-case block

		// stick all the attributes together in a single string
		var winAttributes;
		winAttributes  =  "width=" +      winWidth;
		winAttributes += ",height=" +     winHeight;
		winAttributes += ",location=" +   winLocation;
		winAttributes += ",menubar=" +    winMenubar;
		winAttributes += ",status=" +     winStatus;
		winAttributes += ",scrollbars=" + winScrollbars;
		winAttributes += ",resizable=" +  winResizable;
		winAttributes += ",toolbar=" +    winToolbar;

		// stick the "onclick" attribute stuff together as a string
		var onclick = "popupWin('" + href + "','" + winAttributes + "', '";
		onclick    += rel + "');return false;";

		// attach the onclick attribute to the anchor tag
		anchor.setAttribute("onclick", onclick);

		// if not IE we're done
		if (!document.all) continue;

		/* IE is... "special" -- you have to attach a function reference to events
		for IE elements */
		anchor.onclick = function() {
			popupWin(this.href, winAttributes, this.rel);
			return false;
		}

	} // end for loop
} // end popupWindows

// Use jQuery to start it up.
if (!jQuery){
	var errMsg="jQuery is required for this script to work properly.\nPlease install jQuery 1.2 or higher.";
	alert(errMsg);
	throw new Error(errMsg);
}

jQuery.noConflict();
jQuery(document).ready(init_popupwin);