var is_regexp        = (window.RegExp) ? true : false;


function objeto(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 toggle_collapse(objid)
{
	if (!is_regexp)
	{
		return false;
	}

	var obj = objeto('collapseobj_' + objid);
	var img = objeto('collapseimg_' + objid);
	var cel = objeto('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;
}