var gr = 0;

function setSizeStyle() {
    if (document.getElementById) {
        var styleCookie = getCookie("fontSize");
		var fs = [-2, -1, 0, 1, 2];
        var styleIDs = ["PlusM2", "PlusM1", "Plus0", "Plus1", "Plus2"];
        for (var i = 0; i < styleIDs.length; i++) {
            if (styleCookie == styleIDs[i]) {
                document.getElementById(styleIDs[i]).disabled = false;   
				gr = fs[i];         
            } else {
                document.getElementById(styleIDs[i]).disabled = true; 
            }
        }
    }
}
// set active style now, before content renders
setSizeStyle();

// invoked by clicking on sizer icons
function changeSizeStyle(param) {
	if(param == 1)gr--;
	if(param == 2)gr++;
	if(gr > 2)gr--;
	if(gr < -2)gr++;
	if(gr >= 0)styleID = "Plus" + gr;
	else styleID = "PlusM" + gr*(-1);
    setCookie("fontSize", styleID, getExpDate(180, 0, 0));
    setSizeStyle();
}

function getExpDate(days, hours, minutes) {
    var expDate = new Date();
    if (typeof days == "number" && typeof hours == "number" && typeof hours == "number") {
        expDate.setDate(expDate.getDate() + parseInt(days));
        expDate.setHours(expDate.getHours() + parseInt(hours));
        expDate.setMinutes(expDate.getMinutes() + parseInt(minutes));
        return expDate.toGMTString();
    }
}

function getCookieVal(offset) {
    var endstr = document.cookie.indexOf (";", offset);
    if (endstr == -1) {
        endstr = document.cookie.length;
    }
    return unescape(document.cookie.substring(offset, endstr));
}

function getCookie(name) {
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen) {
        var j = i + alen;
        if (document.cookie.substring(i, j) == arg) {
            return getCookieVal(j);
        }
        i = document.cookie.indexOf(" ", i) + 1;
        if (i == 0) break; 
    }
    return null;
}

// store cookie value with optional details as needed
function setCookie(name, value, expires, path, domain, secure) {
    document.cookie = name + "=" + escape (value) +
        ((expires) ? "; expires=" + expires : "") +
        ((path) ? "; path=" + path : "") +
        ((domain) ? "; domain=" + domain : "") +
        ((secure) ? "; secure" : "");
}

// remove the cookie by setting ancient expiration date
function deleteCookie(name,path,domain) {
    if (getCookie(name)) {
        document.cookie = name + "=" +
            ((path) ? "; path=" + path : "") +
            ((domain) ? "; domain=" + domain : "") +
            "; expires=Thu, 01-Jan-70 00:00:01 GMT";
    }
}