/* eslint-disable camelcase */
// Miscellaneous core Javascript functions for Moodle
// Global M object is initilised in inline javascript

/**
 * Add module to list of available modules that can be loaded from YUI.
 * @param {Array} modules
 */
M.yui.add_module = function(modules) {
    for (var modname in modules) {
        YUI_config.modules[modname] = modules[modname];
    }
    // Ensure thaat the YUI_config is applied to the main YUI instance.
    Y.applyConfig(YUI_config);
};
/**
 * The gallery version to use when loading YUI modules from the gallery.
 * Will be changed every time when using local galleries.
 */
M.yui.galleryversion = '2010.04.21-21-51';

/**
 * Various utility functions
 */
M.util = M.util || {};

/**
 * Language strings - initialised from page footer.
 */
M.str = M.str || {};

/**
 * Returns url for images.
 * @param {String} imagename
 * @param {String} component
 * @return {String}
 */
M.util.image_url = function(imagename, component) {

    if (!component || component == '' || component == 'moodle' || component == 'core') {
        component = 'core';
    }

    var url = M.cfg.wwwroot + '/theme/image.php';
    if (M.cfg.themerev > 0 && M.cfg.slasharguments == 1) {
        if (!M.cfg.svgicons) {
            url += '/_s';
        }
        url += '/' + M.cfg.theme + '/' + component + '/' + M.cfg.themerev + '/' + imagename;
    } else {
        url += '?theme=' + M.cfg.theme + '&component=' + component + '&rev=' + M.cfg.themerev + '&image=' + imagename;
        if (!M.cfg.svgicons) {
            url += '&svg=0';
        }
    }

    return url;
};

M.util.in_array = function(item, array) {
    return array.indexOf(item) !== -1;
};

/**
 * Init a collapsible region, see print_collapsible_region in weblib.php
 * @param {YUI} Y YUI3 instance with all libraries loaded
 * @param {String} id the HTML id for the div.
 * @param {String} userpref the user preference that records the state of this box. false if none.
 * @param {String} strtooltip
 */
M.util.init_collapsible_region = function(Y, id, userpref, strtooltip) {
    Y.use('anim', function(Y) {
        new M.util.CollapsibleRegion(Y, id, userpref, strtooltip);
    });
};

/**
 * Object to handle a collapsible region : instantiate and forget styled object
 *
 * @class
 * @constructor
 * @param {YUI} Y YUI3 instance with all libraries loaded
 * @param {String} id The HTML id for the div.
 * @param {String} userpref The user preference that records the state of this box. false if none.
 * @param {String} strtooltip
 */
M.util.CollapsibleRegion = function(Y, id, userpref, strtooltip) {
    // Record the pref name
    this.userpref = userpref;

    // Find the divs in the document.
    this.div = Y.one('#'+id);

    // Get the caption for the collapsible region
    var caption = this.div.one('#'+id + '_caption');

    // Create a link
    var a = Y.Node.create('<a href="#"></a>');
    a.setAttribute('title', strtooltip);

    // Get all the nodes from caption, remove them and append them to <a>
    while (caption.hasChildNodes()) {
        child = caption.get('firstChild');
        child.remove();
        a.append(child);
    }
    caption.append(a);

    // Get the height of the div at this point before we shrink it if required
    var height = this.div.get('offsetHeight');
    var collapsedimage = 't/collapsed'; // ltr mode
    if (right_to_left()) {
        collapsedimage = 't/collapsed_rtl';
    }
    if (this.div.hasClass('collapsed')) {
        // Add the correct image and record the YUI node created in the process
        this.icon = Y.Node.create('<img src="'+M.util.image_url(collapsedimage, 'moodle')+'" alt="" class="icon" />');
        // Shrink the div as it is collapsed by default
        this.div.setStyle('height', caption.get('offsetHeight')+'px');
    } else {
        // Add the correct image and record the YUI node created in the process
        this.icon = Y.Node.create('<img src="'+M.util.image_url('t/expanded', 'moodle')+'" alt="" class="icon" />');
    }
    a.append(this.icon);

    // Create the animation.
    var animation = new Y.Anim({
        node: this.div,
        duration: 0.3,
        easing: Y.Easing.easeBoth,
        to: {height:caption.get('offsetHeight')},
        from: {height:height}
    });

    animation.on('start', () => M.util.js_pending('CollapsibleRegion'));
    animation.on('resume', () => M.util.js_pending('CollapsibleRegion'));
    animation.on('pause', () => M.util.js_complete('CollapsibleRegion'));

    // Handler for the animation finishing.
    animation.on('end', function() {
        this.div.toggleClass('collapsed');
        var collapsedimage = 't/collapsed'; // ltr mode
        if (right_to_left()) {
            collapsedimage = 't/collapsed_rtl';
            } else {
            collapsedimage = 't/collapsed';
            }
        if (this.div.hasClass('collapsed')) {
            this.icon.set('src', M.util.image_url(collapsedimage, 'moodle'));
        } else {
            this.icon.set('src', M.util.image_url('t/expanded', 'moodle'));
        }

        M.util.js_complete('CollapsibleRegion');
    }, this);

    // Hook up the event handler.
    a.on('click', function(e, animation) {
        e.preventDefault();
        // Animate to the appropriate size.
        if (animation.get('running')) {
            animation.stop();
        }
        animation.set('reverse', this.div.hasClass('collapsed'));
        // Update the user preference.
        if (this.userpref) {
            require(['core_user/repository'], function(UserRepository) {
                UserRepository.setUserPreference(this.userpref, !this.div.hasClass('collapsed'));
            }.bind(this));
        }
        animation.run();
    }, this, animation);
};

/**
 * The user preference that stores the state of this box.
 * @property userpref
 * @type String
 */
M.util.CollapsibleRegion.prototype.userpref = null;

/**
 * The key divs that make up this
 * @property div
 * @type Y.Node
 */
M.util.CollapsibleRegion.prototype.div = null;

/**
 * The key divs that make up this
 * @property icon
 * @type Y.Node
 */
M.util.CollapsibleRegion.prototype.icon = null;

/**
 * Makes a best effort to connect back to Moodle to update a user preference,
 * however, there is no mechanism for finding out if the update succeeded.
 *
 * Before you can use this function in your JavsScript, you must have called
 * user_preference_allow_ajax_update from moodlelib.php to tell Moodle that
 * the udpate is allowed, and how to safely clean and submitted values.
 *
 * @param {String} name the name of the setting to update.
 * @param {String} value the value to set it to.
 *
 * @deprecated since Moodle 4.3.
 */
M.util.set_user_preference = function(name, value) {
    Y.log('M.util.set_user_preference is deprecated. Please use the "core_user/repository" module instead.', 'warn');

    require(['core_user/repository'], function(UserRepository) {
        UserRepository.setUserPreference(name, value);
    });
};

/**
 * Prints a confirmation dialog in the style of DOM.confirm().
 *
 * @method show_confirm_dialog
 * @param {EventFacade} e
 * @param {Object} args
 * @param {String} args.message The question to ask the user
 * @param {Function} [args.callback] A callback to apply on confirmation.
 * @param {Object} [args.scope] The scope to use when calling the callback.
 * @param {Object} [args.callbackargs] Any arguments to pass to the callback.
 * @param {String} [args.cancellabel] The label to use on the cancel button.
 * @param {String} [args.continuelabel] The label to use on the continue button.
 */
M.util.show_confirm_dialog = (e, {
    message,
    continuelabel,
    callback = null,
    scope = null,
    callbackargs = [],
} = {}) => {
    if (e.preventDefault) {
        e.preventDefault();
    }

    require(
        ['core/notification', 'core/str', 'core_form/changechecker', 'core/normalise'],
        function(Notification, Str, FormChangeChecker, Normalise) {

            if (scope === null && e.target) {
                // Fall back to the event target if no scope provided.
                scope = e.target;
            }

            Notification.saveCancelPromise(
                Str.get_string('confirmation', 'admin'),
                message,
                continuelabel || Str.get_string('yes', 'moodle'),
            )
            .then(() => {
                if (callback) {
                    callback.apply(scope, callbackargs);
                    return;
                }

                if (!e.target) {
                    window.console.error(
                        `M.util.show_confirm_dialog: No target found for event`,
                        e
                    );
                    return;
                }

                const target = Normalise.getElement(e.target);

                if (target.closest('a')) {
                    window.location = target.closest('a').getAttribute('href');
                    return;
                } else if (target.closest('input') || target.closest('button')) {
                    const form = target.closest('form');
                    const hiddenValue = document.createElement('input');
                    hiddenValue.setAttribute('type', 'hidden');
                    hiddenValue.setAttribute('name', target.getAttribute('name'));
                    hiddenValue.setAttribute('value', target.getAttribute('value'));
                    form.appendChild(hiddenValue);
                    FormChangeChecker.markFormAsDirty(form);
                    form.submit();
                    return;
                } else if (target.closest('form')) {
                    const form = target.closest('form');
                    FormChangeChecker.markFormAsDirty(form);
                    form.submit();
                    return;
                }
                window.console.error(
                    `Element of type ${target.tagName} is not supported by M.util.show_confirm_dialog.`
                );

                return;
            })
            .catch(() => {
                // User cancelled.
                return;
            });
        }
    );
};

/** Useful for full embedding of various stuff */
M.util.init_maximised_embed = function(Y, id) {
    var obj = Y.one('#'+id);
    if (!obj) {
        return;
    }

    var get_htmlelement_size = function(el, prop) {
        if (Y.Lang.isString(el)) {
            el = Y.one('#' + el);
        }
        // Ensure element exists.
        if (el) {
            var val = el.getStyle(prop);
            if (val == 'auto') {
                val = el.getComputedStyle(prop);
            }
            val = parseInt(val);
            if (isNaN(val)) {
                return 0;
            }
            return val;
        } else {
            return 0;
        }
    };

    var resize_object = function() {
        obj.setStyle('display', 'none');
        var newwidth = get_htmlelement_size('maincontent', 'width') - 35;

        if (newwidth > 500) {
            obj.setStyle('width', newwidth  + 'px');
        } else {
            obj.setStyle('width', '500px');
        }

        var headerheight = get_htmlelement_size('page-header', 'height');
        var footerheight = get_htmlelement_size('page-footer', 'height');
        var newheight = parseInt(Y.one('body').get('docHeight')) - footerheight - headerheight - 100;
        if (newheight < 400) {
            newheight = 400;
        }
        obj.setStyle('height', newheight+'px');
        obj.setStyle('display', '');
    };

    resize_object();
    // fix layout if window resized too
    Y.use('event-resize', function (Y) {
        Y.on("windowresize", function() {
            resize_object();
        });
    });
};

/**
 * Breaks out all links to the top frame - used in frametop page layout.
 */
M.util.init_frametop = function(Y) {
    Y.all('a').each(function(node) {
        node.set('target', '_top');
    });
    Y.all('form').each(function(node) {
        node.set('target', '_top');
    });
};

/**
 * @deprecated since Moodle 3.3
 */
M.util.init_toggle_class_on_click = function(Y, id, cssselector, toggleclassname, togglecssselector) {
    throw new Error('M.util.init_toggle_class_on_click can not be used any more. Please use jQuery instead.');
};

/**
 * Initialises a colour picker
 *
 * Designed to be used with admin_setting_configcolourpicker although could be used
 * anywhere, just give a text input an id and insert a div with the class admin_colourpicker
 * above or below the input (must have the same parent) and then call this with the
 * id.
 *
 * This code was mostly taken from my [Sam Hemelryk] css theme tool available in
 * contrib/blocks. For better docs refer to that.
 *
 * @param {YUI} Y
 * @param {int} id
 * @param {object} previewconf
 */
M.util.init_colour_picker = function(Y, id, previewconf) {
    /**
     * We need node and event-mouseenter
     */
    Y.use('node', 'event-mouseenter', function(){
        /**
         * The colour picker object
         */
        var colourpicker = {
            box : null,
            input : null,
            image : null,
            preview : null,
            current : null,
            eventClick : null,
            eventMouseEnter : null,
            eventMouseLeave : null,
            eventMouseMove : null,
            width : 300,
            height :  100,
            factor : 5,
            /**
             * Initalises the colour picker by putting everything together and wiring the events
             */
            init : function() {
                this.input = Y.one('#'+id);
                this.box = this.input.ancestor().one('.admin_colourpicker');
                this.image = Y.Node.create('<img alt="" class="colourdialogue" />');
                this.image.setAttribute('src', M.util.image_url('i/colourpicker', 'moodle'));
                this.preview = Y.Node.create('<div class="previewcolour"></div>');
                this.preview.setStyle('width', this.height/2).setStyle('height', this.height/2).setStyle('backgroundColor', this.input.get('value'));
                this.current = Y.Node.create('<div class="currentcolour"></div>');
                this.current.setStyle('width', this.height/2).setStyle('height', this.height/2 -1).setStyle('backgroundColor', this.input.get('value'));
                this.box.setContent('').append(this.image).append(this.preview).append(this.current);

                if (typeof(previewconf) === 'object' && previewconf !== null) {
                    Y.one('#'+id+'_preview').on('click', function(e){
                        if (Y.Lang.isString(previewconf.selector)) {
                            Y.all(previewconf.selector).setStyle(previewconf.style, this.input.get('value'));
                        } else {
                            for (var i in previewconf.selector) {
                                Y.all(previewconf.selector[i]).setStyle(previewconf.style, this.input.get('value'));
                            }
                        }
                    }, this);
                }

                this.eventClick = this.image.on('click', this.pickColour, this);
                this.eventMouseEnter = Y.on('mouseenter', this.startFollow, this.image, this);
            },
            /**
             * Starts to follow the mouse once it enter the image
             */
            startFollow : function(e) {
                this.eventMouseEnter.detach();
                this.eventMouseLeave = Y.on('mouseleave', this.endFollow, this.image, this);
                this.eventMouseMove = this.image.on('mousemove', function(e){
                    this.preview.setStyle('backgroundColor', this.determineColour(e));
                }, this);
            },
            /**
             * Stops following the mouse
             */
            endFollow : function(e) {
                this.eventMouseMove.detach();
                this.eventMouseLeave.detach();
                this.eventMouseEnter = Y.on('mouseenter', this.startFollow, this.image, this);
            },
            /**
             * Picks the colour the was clicked on
             */
            pickColour : function(e) {
                var colour = this.determineColour(e);
                this.input.set('value', colour);
                this.current.setStyle('backgroundColor', colour);
            },
            /**
             * Calculates the colour fromthe given co-ordinates
             */
            determineColour : function(e) {
                var eventx = Math.floor(e.pageX-e.target.getX());
                var eventy = Math.floor(e.pageY-e.target.getY());

                var imagewidth = this.width;
                var imageheight = this.height;
                var factor = this.factor;
                var colour = [255,0,0];

                var matrices = [
                    [  0,  1,  0],
                    [ -1,  0,  0],
                    [  0,  0,  1],
                    [  0, -1,  0],
                    [  1,  0,  0],
                    [  0,  0, -1]
                ];

                var matrixcount = matrices.length;
                var limit = Math.round(imagewidth/matrixcount);
                var heightbreak = Math.round(imageheight/2);

                for (var x = 0; x < imagewidth; x++) {
                    var divisor = Math.floor(x / limit);
                    var matrix = matrices[divisor];

                    colour[0] += matrix[0]*factor;
                    colour[1] += matrix[1]*factor;
                    colour[2] += matrix[2]*factor;

                    if (eventx==x) {
                        break;
                    }
                }

                var pixel = [colour[0], colour[1], colour[2]];
                if (eventy < heightbreak) {
                    pixel[0] += Math.floor(((255-pixel[0])/heightbreak) * (heightbreak - eventy));
                    pixel[1] += Math.floor(((255-pixel[1])/heightbreak) * (heightbreak - eventy));
                    pixel[2] += Math.floor(((255-pixel[2])/heightbreak) * (heightbreak - eventy));
                } else if (eventy > heightbreak) {
                    pixel[0] = Math.floor((imageheight-eventy)*(pixel[0]/heightbreak));
                    pixel[1] = Math.floor((imageheight-eventy)*(pixel[1]/heightbreak));
                    pixel[2] = Math.floor((imageheight-eventy)*(pixel[2]/heightbreak));
                }

                return this.convert_rgb_to_hex(pixel);
            },
            /**
             * Converts an RGB value to Hex
             */
            convert_rgb_to_hex : function(rgb) {
                var hex = '#';
                var hexchars = "0123456789ABCDEF";
                for (var i=0; i<3; i++) {
                    var number = Math.abs(rgb[i]);
                    if (number == 0 || isNaN(number)) {
                        hex += '00';
                    } else {
                        hex += hexchars.charAt((number-number%16)/16)+hexchars.charAt(number%16);
                    }
                }
                return hex;
            }
        };
        /**
         * Initialise the colour picker :) Hoorah
         */
        colourpicker.init();
    });
};

M.util.init_block_hider = function(Y, config) {
    Y.use('base', 'node', function(Y) {
        M.util.block_hider = M.util.block_hider || (function(){
            var blockhider = function() {
                blockhider.superclass.constructor.apply(this, arguments);
            };
            blockhider.prototype = {
                initializer : function(config) {
                    this.set('block', '#'+this.get('id'));
                    var b = this.get('block'),
                        t = b.one('.title'),
                        a = null,
                        hide,
                        show;
                    if (t && (a = t.one('.block_action'))) {
                        hide = Y.Node.create('<img />')
                            .addClass('block-hider-hide')
                            .setAttrs({
                                alt:        config.tooltipVisible,
                                src:        this.get('iconVisible'),
                                tabIndex:   0,
                                'title':    config.tooltipVisible
                            });
                        hide.on('keypress', this.updateStateKey, this, true);
                        hide.on('click', this.updateState, this, true);

                        show = Y.Node.create('<img />')
                            .addClass('block-hider-show')
                            .setAttrs({
                                alt:        config.tooltipHidden,
                                src:        this.get('iconHidden'),
                                tabIndex:   0,
                                'title':    config.tooltipHidden
                            });
                        show.on('keypress', this.updateStateKey, this, false);
                        show.on('click', this.updateState, this, false);

                        a.insert(show, 0).insert(hide, 0);
                    }
                },
                updateState : function(e, hide) {
                    require(['core_user/repository'], function(UserRepository) {
                        UserRepository.setUserPreference(this.get('preference'), hide);
                    }.bind(this));
                    if (hide) {
                        this.get('block').addClass('hidden');
                        this.get('block').one('.block-hider-show').focus();
                    } else {
                        this.get('block').removeClass('hidden');
                        this.get('block').one('.block-hider-hide').focus();
                    }
                },
                updateStateKey : function(e, hide) {
                    if (e.keyCode == 13) { //allow hide/show via enter key
                        this.updateState(this, hide);
                    }
                }
            };
            Y.extend(blockhider, Y.Base, blockhider.prototype, {
                NAME : 'blockhider',
                ATTRS : {
                    id : {},
                    preference : {},
                    iconVisible : {
                        value : M.util.image_url('t/switch_minus', 'moodle')
                    },
                    iconHidden : {
                        value : M.util.image_url('t/switch_plus', 'moodle')
                    },
                    block : {
                        setter : function(node) {
                            return Y.one(node);
                        }
                    }
                }
            });
            return blockhider;
        })();
        new M.util.block_hider(config);
    });
};

/**
 * @var pending_js - The keys are the list of all pending js actions.
 * @type Object
 */
M.util.pending_js = [];
M.util.complete_js = [];

/**
 * Register any long running javascript code with a unique identifier.
 * This is used to ensure that Behat steps do not continue with interactions until the page finishes loading.
 *
 * All calls to M.util.js_pending _must_ be followed by a subsequent call to M.util.js_complete with the same exact
 * uniqid.
 *
 * This function may also be called with no arguments to test if there is any js calls pending.
 *
 * The uniqid specified may be any Object, including Number, String, or actual Object; however please note that the
 * paired js_complete function performs a strict search for the key specified. As such, if using an Object, the exact
 * Object must be passed into both functions.
 *
 * @param   {Mixed}     uniqid Register long-running code against the supplied identifier
 * @return  {Number}    Number of pending items
 */
M.util.js_pending = function(uniqid) {
    if (typeof uniqid !== 'undefined') {
        M.util.pending_js.push(uniqid);
    }

    return M.util.pending_js.length;
};

// Start this asap.
M.util.js_pending('init');

/**
 * Register listeners for Y.io start/end so we can wait for them in behat.
 */
YUI.add('moodle-core-io', function(Y) {
    Y.on('io:start', function(id) {
        M.util.js_pending('io:' + id);
    });
    Y.on('io:end', function(id) {
        M.util.js_complete('io:' + id);
    });
}, '@VERSION@', {
    condition: {
        trigger: 'io-base',
        when: 'after'
    }
});

/**
 * Unregister some long running javascript code using the unique identifier specified in M.util.js_pending.
 *
 * This function must be matched with an identical call to M.util.js_pending.
 *
 * @param   {Mixed}     uniqid Register long-running code against the supplied identifier
 * @return  {Number}    Number of pending items remaining after removing this item
 */
M.util.js_complete = function(uniqid) {
    const index = M.util.pending_js.indexOf(uniqid);
    if (index >= 0) {
        M.util.complete_js.push(M.util.pending_js.splice(index, 1)[0]);
    } else {
        window.console.log("Unable to locate key for js_complete call", uniqid);
    }

    return M.util.pending_js.length;
};

/**
 * Returns a string registered in advance for usage in JavaScript
 *
 * If you do not pass the third parameter, the function will just return
 * the corresponding value from the M.str object. If the third parameter is
 * provided, the function performs {$a} placeholder substitution in the
 * same way as PHP get_string() in Moodle does.
 *
 * @param {String} identifier string identifier
 * @param {String} component the component providing the string
 * @param {Object|String} [a] optional variable to populate placeholder with
 */
M.util.get_string = function(identifier, component, a) {
    var stringvalue;

    if (M.cfg.developerdebug) {
        // creating new instance if YUI is not optimal but it seems to be better way then
        // require the instance via the function API - note that it is used in rare cases
        // for debugging only anyway
        // To ensure we don't kill browser performance if hundreds of get_string requests
        // are made we cache the instance we generate within the M.util namespace.
        // We don't publicly define the variable so that it doesn't get abused.
        if (typeof M.util.get_string_yui_instance === 'undefined') {
            M.util.get_string_yui_instance = new YUI({ debug : true });
        }
        var Y = M.util.get_string_yui_instance;
    }

    if (!M.str.hasOwnProperty(component) || !M.str[component].hasOwnProperty(identifier)) {
        stringvalue = '[[' + identifier + ',' + component + ']]';
        if (M.cfg.developerdebug) {
            Y.log('undefined string ' + stringvalue, 'warn', 'M.util.get_string');
        }
        return stringvalue;
    }

    stringvalue = M.str[component][identifier];

    if (typeof a == 'undefined') {
        // no placeholder substitution requested
        return stringvalue;
    }

    if (typeof a == 'number' || typeof a == 'string') {
        // replace all occurrences of {$a} with the placeholder value
        stringvalue = stringvalue.replace(/\{\$a\}/g, a);
        return stringvalue;
    }

    if (typeof a == 'object') {
        // replace {$a->key} placeholders
        for (var key in a) {
            if (typeof a[key] != 'number' && typeof a[key] != 'string') {
                if (M.cfg.developerdebug) {
                    Y.log('invalid value type for $a->' + key, 'warn', 'M.util.get_string');
                }
                continue;
            }
            var search = '{$a->' + key + '}';
            search = search.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&');
            search = new RegExp(search, 'g');
            stringvalue = stringvalue.replace(search, a[key]);
        }
        return stringvalue;
    }

    if (M.cfg.developerdebug) {
        Y.log('incorrect placeholder type', 'warn', 'M.util.get_string');
    }
    return stringvalue;
};

/**
 * Set focus on username or password field of the login form.
 * @deprecated since Moodle 3.3.
 */
M.util.focus_login_form = function(Y) {
    Y.log('M.util.focus_login_form no longer does anything. Please use jquery instead.', 'warn', 'javascript-static.js');
};

/**
 * Set focus on login error message.
 * @deprecated since Moodle 3.3.
 */
M.util.focus_login_error = function(Y) {
    Y.log('M.util.focus_login_error no longer does anything. Please use jquery instead.', 'warn', 'javascript-static.js');
};

/**
 * Adds lightbox hidden element that covers the whole node.
 *
 * @param {YUI} Y
 * @param {Node} the node lightbox should be added to
 * @retun {Node} created lightbox node
 */
M.util.add_lightbox = function(Y, node) {
    var WAITICON = {'pix':"i/loading_small",'component':'moodle'};

    // Check if lightbox is already there
    if (node.one('.lightbox')) {
        return node.one('.lightbox');
    }

    node.setStyle('position', 'relative');

    var waiticon = Y.Node.create('<img />')
        .setAttribute('src', M.util.image_url(WAITICON.pix, WAITICON.component))
        .addClass('icon');

    var lightbox = Y.Node.create('<div></div>')
    .setStyles({
        'opacity' : '.75',
        'position' : 'absolute',
        'width' : '100%',
        'height' : '100%',
        'top' : 0,
        'left' : 0,
        'paddingTop': '50%',
        'backgroundColor' : 'white',
        'textAlign' : 'center'
    })
    .setAttribute('class', 'lightbox')
    .hide();

    lightbox.appendChild(waiticon);
    node.append(lightbox);
    return lightbox;
}

/**
 * Appends a hidden spinner element to the specified node.
 *
 * @param {YUI} Y
 * @param {Node} the node the spinner should be added to
 * @return {Node} created spinner node
 */
M.util.add_spinner = function(Y, node) {
    var WAITICON = {'pix':"i/loading_small",'component':'moodle'};

    // Check if spinner is already there
    if (node.one('.spinner')) {
        return node.one('.spinner');
    }

    var spinner = Y.Node.create('<img />')
        .setAttribute('src', M.util.image_url(WAITICON.pix, WAITICON.component))
        .addClass('spinner icon')
        .hide();

    node.append(spinner);
    return spinner;
}

/**
 * @deprecated since Moodle 3.3.
 */
function checkall() {
    throw new Error('checkall can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function checknone() {
    throw new Error('checknone can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function select_all_in_element_with_id(id, checked) {
    throw new Error('select_all_in_element_with_id can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function select_all_in(elTagName, elClass, elId) {
    throw new Error('select_all_in can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function deselect_all_in(elTagName, elClass, elId) {
    throw new Error('deselect_all_in can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function confirm_if(expr, message) {
    throw new Error('confirm_if can not be used any more.');
}

/**
 * @deprecated since Moodle 3.3.
 */
function findParentNode(el, elName, elClass, elId) {
    throw new Error('findParentNode can not be used any more. Please use jQuery instead.');
}

function unmaskPassword(id) {
    var pw = document.getElementById(id);
    var chb = document.getElementById(id+'unmask');

    // MDL-30438 - The capability to changing the value of input type is not supported by IE8 or lower.
    // Replacing existing child with a new one, removed all yui properties for the node.  Therefore, this
    // functionality won't work in IE8 or lower.
    // This is a temporary fixed to allow other browsers to function properly.
    if (Y.UA.ie == 0 || Y.UA.ie >= 9) {
        if (chb.checked) {
            pw.type = "text";
        } else {
            pw.type = "password";
        }
    } else {  //IE Browser version 8 or lower
        try {
            // first try IE way - it can not set name attribute later
            if (chb.checked) {
              var newpw = document.createElement('<input type="text" autocomplete="off" name="'+pw.name+'">');
            } else {
              var newpw = document.createElement('<input type="password" autocomplete="off" name="'+pw.name+'">');
            }
            newpw.attributes['class'].nodeValue = pw.attributes['class'].nodeValue;
        } catch (e) {
            var newpw = document.createElement('input');
            newpw.setAttribute('autocomplete', 'off');
            newpw.setAttribute('name', pw.name);
            if (chb.checked) {
              newpw.setAttribute('type', 'text');
            } else {
              newpw.setAttribute('type', 'password');
            }
            newpw.setAttribute('class', pw.getAttribute('class'));
        }
        newpw.id = pw.id;
        newpw.size = pw.size;
        newpw.onblur = pw.onblur;
        newpw.onchange = pw.onchange;
        newpw.value = pw.value;
        pw.parentNode.replaceChild(newpw, pw);
    }
}

/**
 * @deprecated since Moodle 3.3.
 */
function filterByParent(elCollection, parentFinder) {
    throw new Error('filterByParent can not be used any more. Please use jQuery instead.');
}

/**
 * @deprecated since Moodle 3.3, but shouldn't be used in earlier versions either.
 */
function fix_column_widths() {
    Y.log('fix_column_widths() no longer does anything. Please remove it from your code.', 'warn', 'javascript-static.js');
}

/**
 * @deprecated since Moodle 3.3, but shouldn't be used in earlier versions either.
 */
function fix_column_width(colName) {
    Y.log('fix_column_width() no longer does anything. Please remove it from your code.', 'warn', 'javascript-static.js');
}


/*
   Insert myValue at current cursor position
 */
function insertAtCursor(myField, myValue) {
    // IE support
    if (document.selection) {
        myField.focus();
        sel = document.selection.createRange();
        sel.text = myValue;
    }
    // Mozilla/Netscape support
    else if (myField.selectionStart || myField.selectionStart == '0') {
        var startPos = myField.selectionStart;
        var endPos = myField.selectionEnd;
        myField.value = myField.value.substring(0, startPos)
            + myValue + myField.value.substring(endPos, myField.value.length);
    } else {
        myField.value += myValue;
    }
}

/**
 * Increment a file name.
 *
 * @param string file name.
 * @param boolean ignoreextension do not extract the extension prior to appending the
 *                                suffix. Useful when incrementing folder names.
 * @return string the incremented file name.
 */
function increment_filename(filename, ignoreextension) {
    var extension = '';
    var basename = filename;

    // Split the file name into the basename + extension.
    if (!ignoreextension) {
        var dotpos = filename.lastIndexOf('.');
        if (dotpos !== -1) {
            basename = filename.substr(0, dotpos);
            extension = filename.substr(dotpos, filename.length);
        }
    }

    // Look to see if the name already has (NN) at the end of it.
    var number = 0;
    var hasnumber = basename.match(/^(.*) \((\d+)\)$/);
    if (hasnumber !== null) {
        // Note the current number & remove it from the basename.
        number = parseInt(hasnumber[2], 10);
        basename = hasnumber[1];
    }

    number++;
    var newname = basename + ' (' + number + ')' + extension;
    return newname;
}

/**
 * Return whether we are in right to left mode or not.
 *
 * @return boolean
 */
function right_to_left() {
    var body = Y.one('body');
    var rtl = false;
    if (body && body.hasClass('dir-rtl')) {
        rtl = true;
    }
    return rtl;
}

function openpopup(event, args) {

    if (event) {
        if (event.preventDefault) {
            event.preventDefault();
        } else {
            event.returnValue = false;
        }
    }

    // Make sure the name argument is set and valid.
    var nameregex = /[^a-z0-9_]/i;
    if (typeof args.name !== 'string') {
        args.name = '_blank';
    } else if (args.name.match(nameregex)) {
        // Cleans window name because IE does not support funky ones.
        if (M.cfg.developerdebug) {
            alert('DEVELOPER NOTICE: Invalid \'name\' passed to openpopup(): ' + args.name);
        }
        args.name = args.name.replace(nameregex, '_');
    }

    var fullurl = args.url;
    if (!args.url.match(/https?:\/\//)) {
        fullurl = M.cfg.wwwroot + args.url;
    }
    if (args.fullscreen) {
        args.options = args.options.
                replace(/top=\d+/, 'top=0').
                replace(/left=\d+/, 'left=0').
                replace(/width=\d+/, 'width=' + screen.availWidth).
                replace(/height=\d+/, 'height=' + screen.availHeight);
    }
    var windowobj = window.open(fullurl,args.name,args.options);
    if (!windowobj) {
        return true;
    }

    if (args.fullscreen) {
        // In some browser / OS combinations (E.g. Chrome on Windows), the
        // window initially opens slighly too big. The width and heigh options
        // seem to control the area inside the browser window, so what with
        // scroll-bars, etc. the actual window is bigger than the screen.
        // Therefore, we need to fix things up after the window is open.
        var hackcount = 100;
        var get_size_exactly_right = function() {
            windowobj.moveTo(0, 0);
            windowobj.resizeTo(screen.availWidth, screen.availHeight);

            // Unfortunately, it seems that in Chrome on Ubuntu, if you call
            // something like windowobj.resizeTo(1280, 1024) too soon (up to
            // about 50ms) after the window is open, then it actually behaves
            // as if you called windowobj.resizeTo(0, 0). Therefore, we need to
            // check that the resize actually worked, and if not, repeatedly try
            // again after a short delay until it works (but with a limit of
            // hackcount repeats.
            if (hackcount > 0 && (windowobj.innerHeight < 10 || windowobj.innerWidth < 10)) {
                hackcount -= 1;
                setTimeout(get_size_exactly_right, 10);
            }
        }
        setTimeout(get_size_exactly_right, 0);
    }
    windowobj.focus();

    return false;
}

/** Close the current browser window. */
function close_window(e) {
    if (e.preventDefault) {
        e.preventDefault();
    } else {
        e.returnValue = false;
    }
    window.close();
}

/**
 * Tranfer keyboard focus to the HTML element with the given id, if it exists.
 * @param controlid the control id.
 */
function focuscontrol(controlid) {
    var control = document.getElementById(controlid);
    if (control) {
        control.focus();
    }
}

/**
 * Transfers keyboard focus to an HTML element based on the old style style of focus
 * This function should be removed as soon as it is no longer used
 */
function old_onload_focus(formid, controlname) {
    if (document.forms[formid] && document.forms[formid].elements && document.forms[formid].elements[controlname]) {
        document.forms[formid].elements[controlname].focus();
    }
}

function build_querystring(obj) {
    return convert_object_to_string(obj, '&');
}

function build_windowoptionsstring(obj) {
    return convert_object_to_string(obj, ',');
}

function convert_object_to_string(obj, separator) {
    if (typeof obj !== 'object') {
        return null;
    }
    var list = [];
    for(var k in obj) {
        k = encodeURIComponent(k);
        var value = obj[k];
        if(obj[k] instanceof Array) {
            for(var i in value) {
                list.push(k+'[]='+encodeURIComponent(value[i]));
            }
        } else {
            list.push(k+'='+encodeURIComponent(value));
        }
    }
    return list.join(separator);
}

/**
 * @deprecated since Moodle 3.3.
 */
function stripHTML(str) {
    throw new Error('stripHTML can not be used any more. Please use jQuery instead.');
}

// eslint-disable-next-line no-unused-vars
function updateProgressBar(id, percent, msg, estimate, error) {
    var event,
        el = document.getElementById(id),
        eventData = {};

    if (!el) {
        return;
    }

    eventData.message = msg;
    eventData.percent = percent;
    eventData.estimate = estimate;
    eventData.error = error;

    try {
        event = new CustomEvent('update', {
            bubbles: false,
            cancelable: true,
            detail: eventData
        });
    } catch (exception) {
        if (!(exception instanceof TypeError)) {
            throw exception;
        }
        event = document.createEvent('CustomEvent');
        event.initCustomEvent('update', false, true, eventData);
        event.prototype = window.Event.prototype;
    }

    el.dispatchEvent(event);
}

M.util.help_popups = {
    setup : function(Y) {
        Y.one('body').delegate('click', this.open_popup, 'a.helplinkpopup', this);
    },
    open_popup : function(e) {
        // Prevent the default page action
        e.preventDefault();

        // Grab the anchor that was clicked
        var anchor = e.target.ancestor('a', true);
        var args = {
            'name'          : 'popup',
            'url'           : anchor.getAttribute('href'),
            'options'       : ''
        };
        var options = [
            'height=600',
            'width=800',
            'top=0',
            'left=0',
            'menubar=0',
            'location=0',
            'scrollbars',
            'resizable',
            'toolbar',
            'status',
            'directories=0',
            'fullscreen=0',
            'dependent'
        ]
        args.options = options.join(',');

        openpopup(e, args);
    }
}

/**
 * Custom menu namespace
 */
M.core_custom_menu = {
    /**
     * This method is used to initialise a custom menu given the id that belongs
     * to the custom menu's root node.
     *
     * @param {YUI} Y
     * @param {string} nodeid
     */
    init : function(Y, nodeid) {
        var node = Y.one('#'+nodeid);
        if (node) {
            Y.use('node-menunav', function(Y) {
                // Get the node
                // Remove the javascript-disabled class.... obviously javascript is enabled.
                node.removeClass('javascript-disabled');
                // Initialise the menunav plugin
                node.plug(Y.Plugin.NodeMenuNav);
            });
        }
    }
};

/**
 * Used to store form manipulation methods and enhancments
 */
M.form = M.form || {};

/**
 * Converts a nbsp indented select box into a multi drop down custom control much
 * like the custom menu. Can no longer be used.
 * @deprecated since Moodle 3.3
 */
M.form.init_smartselect = function() {
    throw new Error('M.form.init_smartselect can not be used any more.');
};

/**
 * Initiates the listeners for skiplink interaction
 *
 * @param {YUI} Y
 */
M.util.init_skiplink = function(Y) {
    Y.one(Y.config.doc.body).delegate('click', function(e) {
        e.preventDefault();
        e.stopPropagation();
        var node = Y.one(this.getAttribute('href'));
        node.setAttribute('tabindex', '-1');
        node.focus();
        return true;
    }, 'a.skip');
};