(function (ns) {
    'use strict';
    /**
     * @alias qs.form.TranslateExtension
     * @constructor
     */
    ns.TranslateExtension = function () {
        this.construct.apply(this, arguments);
    };

    var proto = ns.TranslateExtension.prototype;
    proto.construct = function (options) {
        this.options = $.extend({
            formId: undefined,
            languageToolbarContainerId: undefined,
            languageList: undefined,
            contentFields: undefined
        }, options || {});

        this.toolbarContainer = $('#' + this.options.languageToolbarContainerId);

        this.initContentFields();
        return this;
    };

    proto.initContentFields = function () {
        this.toolbarContainer.find(':radio').bind('change', $.proxy(this.onChangeLanguageElement, this));
    };

    proto.onChangeLanguageElement = function (e) {
        var target = e.currentTarget;
        var contentFields = this.options.contentFields;
        switch (target.value) {
            case 'all':
                this.displayLanguageFields(contentFields, true);
                break;
            default:
                this.displayLanguageFields(contentFields, false);
                this.showLanguageFields(contentFields, target.value);
                break;
        }
    };

    proto.displayLanguageFields = function (contentFields, state) {
        var selector = [], languageList = this.options.languageList, elementSelector, i, j;
        for (i in contentFields) {
            if (contentFields.hasOwnProperty(i)) {
                for (j in languageList) {
                    if (languageList.hasOwnProperty(j)) {
                        elementSelector = '#' + contentFields[i] + '-' + contentFields[i];
                        elementSelector += '_' + languageList[j] + '-element';
                        selector.push(elementSelector);
                    }
                }
            }
        }
        selector = selector.join(', ');
        $(selector).removeClass('hidden');
        if (state) {
            $(selector).removeClass('hidden');
        } else {
            $(selector).addClass('hidden');
        }
    };

    proto.showLanguageFields = function (contentFields, language) {
        'use strict';
        var i, contentField;
        for (i in contentFields) {
            if (contentFields.hasOwnProperty(i)) {
                contentField = $('#' + contentFields[i] + '-' + contentFields[i] + '_' + language + '-element');
                if (contentField.length) {
                    contentField.removeClass('hidden');
                }
            }
        }
    };

    /**
     * @static
     * @param formId
     * @return {*}
     */
    ns.TranslateExtension.onErrorCallback = function (formId) {
        var response = Qs_Form.getFormOption(formId, 'response');
        if (!response.isValid) {
            $('#language-all').click();
        }
        return Qs_Form.displayErrors(formId);
    };

})(qs.defineNS('qs.form'));