// Global functions

function addEvent(evt, elem, newFunction) {
	var oldFunction = elem[evt];


	if (typeof elem[evt] == 'function') {

		elem[evt] = function() {
			oldFunction();
			newFunction();
		};

	} else {
		elem[evt] = newFunction;
	}
}

// Generate a new element (with a certain class) and wrap it around the value
function elemWrap(elem, value, className) {
	return '<' + elem + ' class="' + className + '">' + value + '</' + elem + '>';
}


function printPage() {
	window.print(); return false;
}

// Add function to onload handler
function addPrintLink() {
	var elem = document.getElementById("print-link");
	if (elem) {
		addEvent('onclick', elem, printPage);
	}
}
addEvent('onload', window, addPrintLink);


/**
* Determine whether a node's text content is entirely whitespace.
*
* @param nod  A node implementing the |CharacterData| interface (i.e.,
*             a |Text|, |Comment|, or |CDATASection| node
* @return     True if all of the text content of |nod| is whitespace,
*             otherwise false.
*/
function is_all_ws(nod) {
	// Use ECMA-262 Edition 3 String and RegExp features
	return !(/[^\t\n\r ]/.test(nod.data));
}

/**
* Determine if a node should be ignored by the iterator functions.
*
* @param nod  An object implementing the DOM1 |Node| interface.
* @return     true if the node is:
*                1) A |Text| node that is all whitespace
*                2) A |Comment| node
*             and otherwise false.
*/

function is_ignorable(nod) {
	return (nod.nodeType == 8) || // A comment node
          ((nod.nodeType == 3) && is_all_ws(nod)); // a text node, all ws
}

/**
* Version of |firstChild| that skips nodes that are entirely
* whitespace and comments.
*
* @param sib  The reference node.
* @return     Either:
*               1) The first child of |sib| that is not
*                  ignorable according to |is_ignorable|, or
*               2) null if no such node exists.
*/
function first_child(par) {
	var res = par.firstChild;
	while (res) {
		if (!is_ignorable(res)) return res;
		res = res.nextSibling;
	}
	return null;
}

function textSize(op)
{
	var currentTextSize = document.body.style.fontSize;
	if(currentTextSize =='')
	{
		currentTextSize = '1em';
	}
	
	var result = Number(currentTextSize.replace('em', ''));
	
	if(op == 'increase')
	{
		document.body.style.fontSize = (result + 0.1) + 'em';
	}
	else if(op == 'decrease')
	{
		document.body.style.fontSize = (result  - 0.1) + 'em';
	}
}