@oat-sa/tao-item-runner-qti/src/qtiItem/helper/container.js

TAO QTI Item Runner modules

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2016 (original work) Open Assessment Technologies SA
 **/
import _ from 'lodash';
import $ from 'jquery';

/**
 * Prefix used to the variable storage
 * @type String
 */
var _prefix = 'x-tao-';

/**
 * Check if the element is of a qti container type
 *
 * @private
 * @param {Object} element
 * @returns {Boolean}
 */
function _checkContainerType(element) {
    if (_.isFunction(element.initContainer) && _.isFunction(element.body)) {
        return true;
    } else {
        throw 'the element is not of a container type';
    }
}

/**
 * Get the body element of the container
 *
 * @private
 * @param {Object} element
 * @returns {JQuery}
 */
function _getBodyDom(element) {
    if (_checkContainerType(element)) {
        return $('<div>')
            .html(element.body())
            .find('.x-tao-wrapper');
    }
}

/**
 * Add a class to the body element of the qti container
 *
 * @private
 * @param {Object} element
 * @param {String} newClass
 * @param {String} [oldClass]
 */
function _setBodyDomClass(element, newClass, oldClass) {
    if (_checkContainerType(element) && (oldClass || newClass)) {
        var $wrapper = $('<div>').html(element.body());
        //set css class to element
        _setDomClass($wrapper, newClass, oldClass);
        //set to the model
        element.body($wrapper.html());
    }
}

/**
 * Switch class to the wrapped DOM
 *
 * @param {JQuery} $wrapper
 * @param {String} newClass
 * @param {String} oldClass
 * @returns {undefined}
 */
function _setDomClass($wrapper, newClass, oldClass) {
    var $bodyDom = $wrapper.find('.x-tao-wrapper');
    if (!$bodyDom.length) {
        //create one
        $wrapper.wrapInner('<div class="x-tao-wrapper">');
        $bodyDom = $wrapper.find('.x-tao-wrapper');
    }
    if (oldClass) {
        $bodyDom.removeClass(oldClass);
    }
    if (newClass) {
        $bodyDom.addClass(newClass);
    }
}

/**
 * Add manually the encoded information to a dom element
 *
 * @param {JQuery} $wrapper - the wrapper of the element that will holds the information
 * @param {String} dataName - the name of the information
 * @param {String} newValue - the new value to be added
 * @param {String} [oldValue] - the old value to be removed
 * @returns {undefined}
 */
function setEncodedDataToDom($wrapper, dataName, newValue, oldValue) {
    _setDomClass($wrapper, _getEncodedDataString(dataName, newValue), _getEncodedDataString(dataName, oldValue));
}

/**
 * Get the full variable name for the data store
 *
 * @param {String} dataName
 * @param {String} value
 * @returns {String}
 */
function _getEncodedDataString(dataName, value) {
    if (dataName && value) {
        return _prefix + dataName + '-' + value;
    }
    return '';
}

/**
 * Set a data string to the element identified by its dataName
 *
 * @param {Object} element
 * @param {String} dataName
 * @param {String} newValue
 * @returns {undefined}
 */
function setEncodedData(element, dataName, newValue) {
    var oldValue = getEncodedData(element, dataName);
    return _setBodyDomClass(
        element,
        _getEncodedDataString(dataName, newValue),
        _getEncodedDataString(dataName, oldValue)
    );
}

/**
 * Remove the stored data from the element by its dataName
 *
 * @param {Object} element
 * @param {String} dataName
 * @returns {unresolved}
 */
function removeEncodedData(element, dataName) {
    var oldValue = getEncodedData(element, dataName);
    if (dataName && oldValue) {
        _setBodyDomClass(element, '', _getEncodedDataString(dataName, oldValue));
    }
}

/**
 * Check if the stored data exist
 *
 * @param {Object} element
 * @param {String} dataName
 * @param {String} value
 * @returns {Boolean}
 */
function hasEncodedData(element, dataName, value) {
    var $body = _getBodyDom(element);
    if ($body && $body.length && dataName && value) {
        return $body.hasClass(_getEncodedDataString(dataName, value));
    }
    return false;
}

/**
 * Get the encoded data identified by its dataName
 *
 * @param {Object} element
 * @param {String} dataName
 * @returns {String}
 */
function getEncodedData(element, dataName) {
    var regex, matches;
    var $body = _getBodyDom(element);
    if (dataName && $body && $body.length && $body.attr('class')) {
        regex = new RegExp(_prefix + dataName + '-([a-zA-Z0-9-._]*)');
        matches = $body.attr('class').match(regex);
        if (matches) {
            return matches[1];
        }
    }
}

/**
 * Provide a set of helper functions to set,retirve and manage string data to a container type qti element.
 */
export default {
    setEncodedData: setEncodedData,
    hasEncodedData: hasEncodedData,
    getEncodedData: getEncodedData,
    removeEncodedData: removeEncodedData,
    setEncodedDataToDom: setEncodedDataToDom
};