// #############################################################################
// Browser detection and limitation workarounds

// Define the browser we have instead of multiple calls throughout the file
var userAgent = navigator.userAgent.toLowerCase();
var is_opera  = ((userAgent.indexOf('opera') != -1) || (typeof(window.opera) != 'undefined'));
var is_saf    = ((userAgent.indexOf('applewebkit') != -1) || (navigator.vendor == 'Apple Computer, Inc.'));
var is_webtv  = (userAgent.indexOf('webtv') != -1);
var is_ie     = ((userAgent.indexOf('msie') != -1) && (!is_opera) && (!is_saf) && (!is_webtv));
var is_ie4    = ((is_ie) && (userAgent.indexOf('msie 4.') != -1));
var is_ie7    = ((is_ie) && (userAgent.indexOf('msie 7.') != -1));
var is_moz    = ((navigator.product == 'Gecko') && (!is_saf));
var is_kon    = (userAgent.indexOf('konqueror') != -1);
var is_ns     = ((userAgent.indexOf('compatible') == -1) && (userAgent.indexOf('mozilla') != -1) && (!is_opera) && (!is_webtv) && (!is_saf));
var is_ns4    = ((is_ns) && (parseInt(navigator.appVersion) == 4));
var is_mac    = (userAgent.indexOf('mac') != -1);

// Catch possible bugs with WebTV and other older browsers
var is_regexp = (window.RegExp) ? true : false;

// Is the visiting browser compatible with AJAX?
var AJAX_Compatible = false;

// Help out old versions of IE that don't understand element.style.cursor = 'pointer'
var pointer_cursor = (is_ie ? 'hand' : 'pointer');

/**
* Workaround for heinous IE bug - add special vBlength property to all strings
* This method is applied to ALL string objects automatically
*
* @return	integer
*/
String.prototype.vBlength = function()
{
	return (is_ie && this.indexOf('\n') != -1) ? this.replace(/\r?\n/g, '_').length : this.length;
}

if ('1234'.substr(-2, 2) == '12') // (which would be incorrect)
{
	String.prototype.substr_orig = String.prototype.substr;

	/**
	* Overrides IE's original String.prototype.substr to accept negative values
	*
	* @param	integer	Substring start position
	* @param	integer	Substring length
	*
	* @return	string
	*/
	String.prototype.substr = function(start, length)
	{
		return this.substr_orig( (start < 0 ? this.length + start : start), length);
	};
}

/**
* Pop function for browsers that don't have it built in
*
* @param	array	Array from which to pop
*
* @return	mixed	null on empty, value on success
*/
function array_pop(a)
{
	if (typeof a != 'object' || !a.length)
	{
		return null;
	}
	else
	{
		var response = a[a.length - 1];
		a.length--;
		return response;
	}
}

if (typeof Array.prototype.shift === 'undefined')
{
	Array.prototype.shift = function()
	{
		for(var i = 0, b = this[0], l = this.length-1; i < l; i++)
		{
			this[i] = this[i + 1];
		}
		this.length--;
		return b;
	};
}

/**
* Push function for browsers that don't have it built in
*
* @param	array	Array onto which to push
* @param	mixed	Value(s) to push onto - you may use multiple arguments here, eg: array_push(myArray, 1, 2, 3, 4, ...)
*
* @return	integer	Length of array
*/
function array_push(a, values)
{
	for (var i = 1; i < arguments.length; i++)
	{
		a[a.length] = arguments[i];
	}
	return a.length;
}

/**
* Function to emulate document.getElementById
*
* @param	string	Object ID
*
* @return	mixed	null if not found, object if found
*/
function fetch_object(idname)
{
	if (document.getElementById)
	{
		return document.getElementById(idname);
	}
	else if (document.all)
	{
		return document.all[idname];
	}
	else if (document.layers)
	{
		return document.layers[idname];
	}
	else
	{
		return null;
	}
}

/**
* Function to emulate document.getElementsByTagName
*
* @param	object	Parent object (eg: document)
* @param	string	Tag type (eg: 'td')
*
* @return	array
*/
function fetch_tags(parentobj, tag)
{
	if (parentobj == null)
	{
		return new Array();
	}
	else if (typeof parentobj.getElementsByTagName != 'undefined')
	{
		return parentobj.getElementsByTagName(tag);
	}
	else if (parentobj.all && parentobj.all.tags)
	{
		return parentobj.all.tags(tag);
	}
	else
	{
		return new Array();
	}
}

/**
* Function to count the number of tags in an object
*
* @param	object	Parent object (eg: document)
* @param	string	Tag type (eg: 'td')
*
* @return	integer
*/
function fetch_tag_count(parentobj, tag)
{
	return fetch_tags(parentobj, tag).length;
}




// #############################################################################
// Cookie handlers

/**
* Sets a cookie
*
* @param	string	Cookie name
* @param	string	Cookie value
* @param	date	Cookie expiry date
*/
function set_cookie(name, value, expires)
{
	document.cookie = name + '=' + escape(value) + '; path=/' + (typeof expires != 'undefined' ? '; expires=' + expires.toGMTString() : '');
}

/**
* Deletes a cookie
*
* @param	string	Cookie name
*/
function delete_cookie(name)
{
	document.cookie = name + '=' + '; expires=Thu, 01-Jan-70 00:00:01 GMT' +  '; path=/';
}

/**
* Fetches the value of a cookie
*
* @param	string	Cookie name
*
* @return	string
*/
function fetch_cookie(name)
{
	cookie_name = name + '=';
	cookie_length = document.cookie.length;
	cookie_begin = 0;
	while (cookie_begin < cookie_length)
	{
		value_begin = cookie_begin + cookie_name.length;
		if (document.cookie.substring(cookie_begin, value_begin) == cookie_name)
		{
			var value_end = document.cookie.indexOf (';', value_begin);
			if (value_end == -1)
			{
				value_end = cookie_length;
			}
			return unescape(document.cookie.substring(value_begin, value_end));
		}
		cookie_begin = document.cookie.indexOf(' ', cookie_begin) + 1;
		if (cookie_begin == 0)
		{
			break;
		}
	}
	return null;
}

// #############################################################################
// Collapsible element handlers

/**
* Toggles the collapse state of an object, and saves state to 'vbulletin_collapse' cookie
*
* @param	string	Unique ID for the collapse group
*
* @return	boolean	false
*/
function hide(objid)
{
	if (!is_regexp)
	{
		return false;
	}

	obj = fetch_object(objid + '-hide');
	img = fetch_object(objid + '-img');
	cel = fetch_object('collapsecel_' + objid);

	if (!obj)
	{
		// nothing to collapse!
		if (img)
		{
			// hide the clicky image if there is one
			img.style.display = 'none';
		}
		return false;
	}

	if (obj.style.display == 'none')
	{
		obj.style.display = '';
		save_collapsed(objid, false);
		if (img)
		{
			img_re = new RegExp("_collapsed\\.gif$");
			img.src = img.src.replace(img_re, '.gif');
		}
		if (cel)
		{
			cel_re = new RegExp("^(thead|tcat)(_collapsed)$");
			cel.className = cel.className.replace(cel_re, '$1');
		}
	}
	else
	{
		obj.style.display = 'none';
		save_collapsed(objid, true);
		if (img)
		{
			img_re = new RegExp("\\.gif$");
			img.src = img.src.replace(img_re, '_collapsed.gif');
		}
		if (cel)
		{
			cel_re = new RegExp("^(thead|tcat)$");
			cel.className = cel.className.replace(cel_re, '$1_collapsed');
		}
	}
	return false;
}

/**
* Updates vbulletin_collapse cookie with collapse preferences
*
* @param	string	Unique ID for the collapse group
* @param	boolean	Add a cookie
*/
function save_collapsed(objid, addcollapsed)
{
	var collapsed = fetch_cookie('vbulletin_collapse');
	var tmp = new Array();

	if (collapsed != null)
	{
		collapsed = collapsed.split('\n');

		for (var i in collapsed)
		{
			if (collapsed[i] != objid && collapsed[i] != '')
			{
				tmp[tmp.length] = collapsed[i];
			}
		}
	}

	if (addcollapsed)
	{
		tmp[tmp.length] = objid;
	}

	expires = new Date();
	expires.setTime(expires.getTime() + (1000 * 86400 * 365));
	set_cookie('vbulletin_collapse', tmp.join('\n'), expires);
}