// Make sure the "FM" namespace object exists
if (typeof FM != 'object') {
    FM = new Object();
}

/**
 * Checks a given class attribute for the presence of a given class
 *
 * @author  Dan Delaney     http://fluidmind.org/
 * @param   element         DOM Element object (or element ID) to remove the class from
 * @param   nameOfClass     The name of the CSS class to check for
 */
FM.checkForClass = function(element, nameOfClass) {
    if (typeof element == 'string') { element = document.getElementById(element); }

    if (element.className == '') {
        return false;
    } else {
        return new RegExp('\\b' + nameOfClass + '\\b').test(element.className);
    }
}


/**
 * Adds a class to an element's class attribute
 *
 * @author  Dan Delaney     http://fluidmind.org/
 * @param   element         DOM Element object (or element ID) to add the class to
 * @param   nameOfClass     Class name to add
 * @see     checkForClass
 */
FM.addClass = function(element, nameOfClass) {
    if (typeof element == 'string') { element = document.getElementById(element); }

    if (!FM.checkForClass(element, nameOfClass)) {
        element.className += (element.className ? ' ' : '') + nameOfClass;
        return true;
    } else {
        return false;
    }
}


/**
 * Removes a class from an element's class attribute
 *
 * @author  Dan Delaney     http://fluidmind.org/
 * @param   element         DOM Element object (or element ID) to remove the class from
 * @param   nameOfClass     Class name to remove
 * @see     checkForClass
 */
FM.removeClass = function(element, nameOfClass) {
    if (typeof element == 'string') { element = document.getElementById(element); }

    if (FM.checkForClass(element, nameOfClass)) {
        element.className = element.className.replace(
            (element.className.indexOf(' ' + nameOfClass) >= 0 ? ' ' + nameOfClass : nameOfClass),
            '');
        return true;
    } else {
        return false;
    }
}


/**
 * Replaces a class with another if the class is present
 *
 * @author  Dan Delaney     http://fluidmind.org/
 * @param   element         DOM Element object (or element ID) to remove the class from
 * @param   class1          Class name to replace
 * @param   class2          Class name to replace it with
 * @see     checkForClass
 * @see     addClass
 * @see     removeClass
 */
FM.replaceClass = function(element, class1, class2) {
    if (typeof element == 'string') { element = document.getElementById(element); }

    if (FM.checkForClass(element, class1)) {
        FM.removeClass(element, class1);
        FM.addClass(element, class2);
        return true;
    } else {
        return false;
    }
}


/**
 * Toggles the specified class on and off
 *
 * @author  Dan Delaney     http://fluidmind.org/
 * @param   element         DOM Element object (or element ID) to toggle the class of
 * @param   nameOfClass     Class name to toggle
 * @see     checkForclass
 * @see     addClass
 * @see     removeClass
 */
FM.toggleClass = function(element, nameOfClass) {
    if (typeof element == 'string') { element = document.getElementById(element); }

    if (FM.checkForClass(element, nameOfClass)) {
        FM.removeClass(element, nameOfClass);
    } else {
        FM.addClass(element, nameOfClass);
    }

    return true;
}