Collect some IDs in cookies

cookiescollector.js

if (!Array.prototype.indexOf) {
    Array.prototype.indexOf = function(elt) {
        var len = this.length >>> 0;
        var from = Number(arguments[1]) || 0;
        from = (from < 0) ? Math.ceil(from) : Math.floor(from);
        if (from < 0) from += len;
        for (; from < len; from++) {
            if (from in this && this[from] === elt) return from;
        }
        return -1;
    };
}

function CookieIDsHistory(name, options) {
    if ((typeof name == 'undefined') || (name.length < 1)) {
        throw 'Please set cookie name.';
    }
    options = options || {};
    this._cookieName = encodeURIComponent(name);
    this._expiresDays = options.days || 0;
    this._itemsLimit = options.limit || 15;
    this._uniqueValues = !!options.unique;
    this._setCookie = function(name, value, days) {
        var expires, host;
        if (days) {
            var date = new Date();
            date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
            expires = '; expires=' + date.toGMTString();
        } else {
            expires = '';
        }
        host = location.hostname.replace(/^www\./i, '');
        document.cookie = name + '=' + value + expires + '; path=/' + '; domain=.' + host;
    };
    this._getCookie = function(name) {
        var cookieName = name + '=';
        var cookieArray = document.cookie.split(';');
        for (var i = 0; i < cookieArray.length; i++) {
            var cookieItem = cookieArray[i];
            while (cookieItem.charAt(0) == ' ') cookieItem = cookieItem.substring(1, cookieItem.length);
            if (cookieItem.indexOf(cookieName) == 0) return cookieItem.substring(cookieName.length, cookieItem.length);
        }
        return '';
    };
    this._delCookie = function(name) {
        this._setCookie(name, '', -1);
    };
    this._getCookieData = function() {
        var items;
        if (!Array.isArray) {
            Array.isArray = function(arg) {
                return Object.prototype.toString.call(arg) === '[object Array]';
            };
        }
        try {
            items = JSON.parse(this._getCookie(this._cookieName)) || [];
        } catch (err) {
            items = [];
        }
        if (!Array.isArray(items)) {
            items = [];
        }
        return items;
    };
    this._setCookieData = function(items) {
        this._setCookie(this._cookieName, JSON.stringify(items), this._expiresDays);
    };
    this.add = function(id) {
        var items = this._getCookieData();
        if (items.length > this._itemsLimit) {
            items.shift();
        }
        if (this._uniqueValues) {
            while (items.indexOf(id) > -1) {
                items.splice(items.indexOf(id), 1);
            }
        }
        items.push(id);
        this._setCookieData(items);
        return this;
    };
    this.remove = function(id) {
        var items = this._getCookieData();
        while (items.indexOf(id) > -1) {
            items.splice(items.indexOf(id), 1);
        }
        this._setCookieData(items);
        return this;
    };
    this.removeOne = function(id) {
        var items = this._getCookieData();
        if (items.indexOf(id) != -1) {
            items.splice(items.indexOf(id), 1);
        }
        this._setCookieData(items);
        return this;
    };
    this.count = function(id) {
        var items = this._getCookieData(),
            counter = 0;
        for (var i = 0; i < items.length; i++) {
            if (items[i] == id) {
                counter++;
            }
        }
        return counter;
    };
    this.length = function() {
        var items = this._getCookieData();
        return items.length;
    };
    this.is = function(id) {
        return !!this.count(id);
    };
    this.unset = function () {
        this._delCookie(this._cookieName);
        return this;
    };
}


/* Usage example: */

var ch = new CookieIDsHistory('_test', { days: 5, limit: 50, unique: true });

// days - How many days cookie will live
// limit - How many IDs will be collected before cutting of old IDs will start
// unique - Can IDs be repeated in the array or not

// Adding IDs to collect.
ch.add(103);
ch.add(345);
ch.add(101);
ch.add(235);
ch.add(101);
ch.add(867);
ch.add(124);

// or simply
ch.add(103).add(345).add(101).add(235).add(101).add(867).add(124);

// Check ID existing.
ch.is(101);

// Count IDs in collection. Note: it makes sense with unique parameter in False state.
ch.count(101);

// Remove only first ID in collection. Note: it makes sense with unique parameter in False state.
ch.removeOne(101);

// Remove all specified IDs in collection.
ch.remove(101);

// Remove cookie.
ch.unset();