Friends.FriendsList = new function() {
    this.createFromTag = function(element) {
        new Friends.FriendsList.Constructor(element);
    };
};

Friends.FriendsList.Constructor = function(element) {
    /** control container. */
    this.control = element;

    /**
     * Чекбоксы. Если чекбокс выбран, то над этим пользователей будет
     * производиться действие.
     */
    this.checkboxes = 0;

    /** Кнопки "Сохранить". */
    this.submits = 0;

    /** Начальные тексты НА кнопках "Сохранить" */
    this.submitsInitial = 0;

    /** Тексты справа от кнопок "Сохранить". */
    this.submitTexts = 0;

    /** Начальные тексты справа от кнопок "Сохранить". */
    this.submitTextsInitial = 0;

    /** Количество отмеченых чекбоксов. */
    this.checked = 0;

    /** Это страница регистрации? */
    this.isRegPage = 0;

    this.init();
};

Friends.FriendsList.Constructor.prototype = new function() {
//public
    this.checkAll = function(_checkbox) {
        var checked = _checkbox.checked;
        this.checked = checked ? 0 : this.checkboxes.length;
        for (var i = 0, l = this.checkboxes.length; i < l; i++)
            this.check(this.checkboxes[i], checked);
    };

    this.check = function(_checkbox, _checked) {
        var row = _checkbox.parentNode.parentNode;

        var checked;
        if (_checked != -1 && !_checkbox.disabled){
            checked = _checkbox.checked = _checked;
        } else {
            checked = !y5.Classes.test(row, "checked");
        }

        this.checkIt(row, checked);

        var cell = y5.Dom.getDescendant(row, 'td', 'mutually'); //y5.cssQuery("td.mutually", row)[0];
        if (cell)
            y5.Classes.assign(cell, "mutually-checked", checked);

        this.disable();

        return true;
    };

//private
    this.checkIt = function(_row, _checked) {
        if (_checked)
        {
            this.checked++;
            addClass(_row, "checked");
        }
        else
        {
            this.checked--;
            delClass(_row, "checked");
        }
    };


    //TODO:may be we should rename this function  - since its toggles state, not just disabling
    //TODO:write this in russian
    this.disable = function() {
        var _this = this;
        if (this.checked == 0)
        {
            if (this.isRegPage)
            {
                this.submits.forEach(function(s, i) { s.disabled = false});
            }
            this.submits.forEach(function(s, i) { s.value = _this.submitsInitial[i] });
            this.submitTexts.forEach(function(s, i) { 
	    	s.innerHTML = _this.submitTextsInitial[i]; 
	   });
        }
        else
        {
            var submitTextsNew = y5.Strings.plural(this.checked,
                    ["пользователь", "пользователя", "пользователей"]);
            this.submitTexts.forEach(function(s, i) { 
	    	s.innerHTML = submitTextsNew; 
	    });

            if (!this.isRegPage)
            {
                this.submits.forEach(function(s, i) { s.disabled = false });
            }
            else
            {
                this.submits.forEach(function(s, i) { s.value = 'Добавить в друзья' });
            }
        }
    };
    
//constructor
    this.init = function() {
        var checkAllInput = y5.Dom.getDescendant(this.control, 'input', 'all');

        if (checkAllInput) {
            checkAllInput.onclick = associateEventWithObject(this, "checkAll");
        }

        this.checkboxes = getByTagName("input", getByTagName("tbody", this.control)[0]);
        for (var i = 0, l = this.checkboxes.length; i < l; i++) {
            this.checkboxes[i].onclick = associateEventWithObject(this, "check", -1);
        }

        this.submits = y5.cssQuery("div.b-submit input[type='submit']", this.control.parentNode);
        this.submitsInitial = this.submits.map(function(s) { return s.value });

        this.submitTexts = y5.cssQuery('div.b-submit p span', this.control.parentNode);	
        this.submitTextsInitial = this.submits.map(function(s) { return s.innerHTML });

        this.isRegPage = y5.Dom.getDescendants(document, 'table', 'b-page-reg').length;

        this.disable();
    };
}

y5.require(['cssQuery', 'Dom', 'Strings'], function() {y5.loaded('{Friends}.FriendsList')});