// 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];
    }
};
/**
 * 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){
    for( var i = 0; i<array.length; i++){
        if(item==array[i]){
            return true;
        }
    }
    return false;
};

/**
 * 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';
    } else {
        collapsedimage = 't/collapsed';
    }
    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="" />');
        // 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="" />');
    }
    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}
    });

    // 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'));
        }
    }, 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) {
            M.util.set_user_preference(this.userpref, !this.div.hasClass('collapsed'));
        }
        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 udpate.
 * @param String the value to set it to.
 */
M.util.set_user_preference = function(name, value) {
    YUI().use('io', function(Y) {
        var url = M.cfg.wwwroot + '/lib/ajax/setuserpref.php?sesskey=' +
                M.cfg.sesskey + '&pref=' + encodeURI(name) + '&value=' + encodeURI(value);

        // If we are a developer, ensure that failures are reported.
        var cfg = {
                method: 'get',
                on: {}
            };
        if (M.cfg.developerdebug) {
            cfg.on.failure = function(id, o, args) {
                alert("Error updating user preference '" + name + "' using ajax. Clicking this link will repeat the Ajax call that failed so you can see the error: ");
            }
        }

        // Make the request.
        Y.io(url, cfg);
    });
};

/**
 * 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 = function(e, args) {
    var target = e.target;
    if (e.preventDefault) {
        e.preventDefault();
    }

    YUI().use('moodle-core-notification-confirm', function(Y) {
        var confirmationDialogue = new M.core.confirm({
            width: '300px',
            center: true,
            modal: true,
            visible: false,
            draggable: false,
            title: M.util.get_string('confirmation', 'admin'),
            noLabel: M.util.get_string('cancel', 'moodle'),
            question: args.message
        });

        // The dialogue was submitted with a positive value indication.
        confirmationDialogue.on('complete-yes', function(e) {
            // Handle any callbacks.
            if (args.callback) {
                if (!Y.Lang.isFunction(args.callback)) {
                    Y.log('Callbacks to show_confirm_dialog must now be functions. Please update your code to pass in a function instead.',
                            'warn', 'M.util.show_confirm_dialog');
                    return;
                }

                var scope = e.target;
                if (Y.Lang.isObject(args.scope)) {
                    scope = args.scope;
                }

                var callbackargs = args.callbackargs || [];
                args.callback.apply(scope, callbackargs);
                return;
            }

            var targetancestor = null,
                targetform = null;

            if (target.test('a')) {
                window.location = target.get('href');

            } else if ((targetancestor = target.ancestor('a')) !== null) {
                window.location = targetancestor.get('href');

            } else if (target.test('input')) {
                targetform = target.ancestor('form', true);
                if (!targetform) {
                    return;
                }
                if (target.get('name') && target.get('value')) {
                    targetform.append('<input type="hidden" name="' + target.get('name') +
                                    '" value="' + target.get('value') + '">');
                }
                targetform.submit();

            } else if (target.test('form')) {
                target.submit();

            } else {
                Y.log("Element of type " + target.get('tagName') +
                        " is not supported by the M.util.show_confirm_dialog function. Use A, INPUT, or FORM",
                        'warn', 'javascript-static');
            }
        }, this);

        if (args.cancellabel) {
            confirmationDialogue.set('noLabel', args.cancellabel);
        }

        if (args.continuelabel) {
            confirmationDialogue.set('yesLabel', args.continuelabel);
        }

        confirmationDialogue.render()
                .show();
    });
};

/** 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('width', '0px');
        obj.setStyle('height', '0px');
        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');
    };

    resize_object();
    // fix layout if window resized too
    window.onresize = 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');
    });
};

/**
 * Finds all nodes that match the given CSS selector and attaches events to them
 * so that they toggle a given classname when clicked.
 *
 * @param {YUI} Y
 * @param {string} id An id containing elements to target
 * @param {string} cssselector A selector to use to find targets
 * @param {string} toggleclassname A classname to toggle
 */
M.util.init_toggle_class_on_click = function(Y, id, cssselector, toggleclassname, togglecssselector) {

    if (togglecssselector == '') {
        togglecssselector = cssselector;
    }

    var node = Y.one('#'+id);
    node.all(cssselector).each(function(n){
        n.on('click', function(e){
            e.stopPropagation();
            if (e.target.test(cssselector) && !e.target.test('a') && !e.target.test('img')) {
                if (this.test(togglecssselector)) {
                    this.toggleClass(toggleclassname);
                } else {
                    this.ancestor(togglecssselector).toggleClass(toggleclassname);
            }
            }
        }, n);
    });
    // Attach this click event to the node rather than all selectors... will be much better
    // for performance
    node.on('click', function(e){
        if (e.target.hasClass('addtoall')) {
            this.all(togglecssselector).addClass(toggleclassname);
        } else if (e.target.hasClass('removefromall')) {
            this.all(togglecssselector+'.'+toggleclassname).removeClass(toggleclassname);
        }
    }, node);
};

/**
 * 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) {
                    M.util.set_user_preference(this.get('preference'), hide);
                    if (hide) {
                        this.get('block').addClass('hidden');
                    } else {
                        this.get('block').removeClass('hidden');
                    }
                },
                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.
 * Should be followed with a call to js_complete with a matching
 * idenfitier when the code is complete. May also be called with no arguments
 * to test if there is any js calls pending. This is relied on by behat so that
 * it can wait for all pending updates before interacting with a page.
 * @param String uniqid - optional, if provided,
 *                        registers this identifier until js_complete is called.
 * @return boolean - True if there is any pending js.
 */
M.util.js_pending = function(uniqid) {
    if (uniqid !== false) {
        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 any long running javascript code by unique identifier.
 * This function should form a matching pair with js_pending
 *
 * @param String uniqid - required, unregisters this identifier
 * @return boolean - True if there is any pending js.
 */
M.util.js_complete = function(uniqid) {
    // Use the Y.Array.indexOf instead of the native because some older browsers do not support
    // the native function. Y.Array polyfills the native function if it does not exist.
    var index = Y.Array.indexOf(M.util.pending_js, uniqid);
    if (index >= 0) {
        M.util.complete_js.push(M.util.pending_js.splice(index, 1));
    }

    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
 */
M.util.focus_login_form = function(Y) {
    var username = Y.one('#username');
    var password = Y.one('#password');

    if (username == null || password == null) {
        // something is wrong here
        return;
    }

    var curElement = document.activeElement
    if (curElement == 'undefined') {
        // legacy browser - skip refocus protection
    } else if (curElement.tagName == 'INPUT') {
        // user was probably faster to focus something, do not mess with focus
        return;
    }

    if (username.get('value') == '') {
        username.focus();
    } else {
        password.focus();
    }
}

/**
 * Set focus on login error message
 */
M.util.focus_login_error = function(Y) {
    var errorlog = Y.one('#loginerrormessage');

    if (errorlog) {
        errorlog.focus();
    }
}
/**
 * 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 />')
    .setAttrs({
        'src' : M.util.image_url(WAITICON.pix, WAITICON.component)
    })
    .setStyles({
        'position' : 'relative',
        'top' : '50%'
    });

    var lightbox = Y.Node.create('<div></div>')
    .setStyles({
        'opacity' : '.75',
        'position' : 'absolute',
        'width' : '100%',
        'height' : '100%',
        'top' : 0,
        'left' : 0,
        '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')
        .addClass('iconsmall')
        .hide();

    node.append(spinner);
    return spinner;
}

//=== old legacy JS code, hopefully to be replaced soon by M.xx.yy and YUI3 code ===

function checkall() {
    var inputs = document.getElementsByTagName('input');
    for (var i = 0; i < inputs.length; i++) {
        if (inputs[i].type == 'checkbox') {
            if (inputs[i].disabled || inputs[i].readOnly) {
                continue;
            }
            inputs[i].checked = true;
        }
    }
}

function checknone() {
    var inputs = document.getElementsByTagName('input');
    for (var i = 0; i < inputs.length; i++) {
        if (inputs[i].type == 'checkbox') {
            if (inputs[i].disabled || inputs[i].readOnly) {
                continue;
            }
            inputs[i].checked = false;
        }
    }
}

/**
 * Either check, or uncheck, all checkboxes inside the element with id is
 * @param id the id of the container
 * @param checked the new state, either '' or 'checked'.
 */
function select_all_in_element_with_id(id, checked) {
    var container = document.getElementById(id);
    if (!container) {
        return;
    }
    var inputs = container.getElementsByTagName('input');
    for (var i = 0; i < inputs.length; ++i) {
        if (inputs[i].type == 'checkbox' || inputs[i].type == 'radio') {
            inputs[i].checked = checked;
        }
    }
}

function select_all_in(elTagName, elClass, elId) {
    var inputs = document.getElementsByTagName('input');
    inputs = filterByParent(inputs, function(el) {return findParentNode(el, elTagName, elClass, elId);});
    for(var i = 0; i < inputs.length; ++i) {
        if(inputs[i].type == 'checkbox' || inputs[i].type == 'radio') {
            inputs[i].checked = 'checked';
        }
    }
}

function deselect_all_in(elTagName, elClass, elId) {
    var inputs = document.getElementsByTagName('INPUT');
    inputs = filterByParent(inputs, function(el) {return findParentNode(el, elTagName, elClass, elId);});
    for(var i = 0; i < inputs.length; ++i) {
        if(inputs[i].type == 'checkbox' || inputs[i].type == 'radio') {
            inputs[i].checked = '';
        }
    }
}

function confirm_if(expr, message) {
    if(!expr) {
        return true;
    }
    return confirm(message);
}


/*
    findParentNode (start, elementName, elementClass, elementID)

    Travels up the DOM hierarchy to find a parent element with the
    specified tag name, class, and id. All conditions must be met,
    but any can be ommitted. Returns the BODY element if no match
    found.
*/
function findParentNode(el, elName, elClass, elId) {
    while (el.nodeName.toUpperCase() != 'BODY') {
        if ((!elName || el.nodeName.toUpperCase() == elName) &&
            (!elClass || el.className.indexOf(elClass) != -1) &&
            (!elId || el.id == elId)) {
            break;
        }
        el = el.parentNode;
    }
    return el;
}

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);
    }
}

function filterByParent(elCollection, parentFinder) {
    var filteredCollection = [];
    for (var i = 0; i < elCollection.length; ++i) {
        var findParent = parentFinder(elCollection[i]);
        if (findParent.nodeName.toUpperCase() != 'BODY') {
            filteredCollection.push(elCollection[i]);
        }
    }
    return filteredCollection;
}

/*
    All this is here just so that IE gets to handle oversized blocks
    in a visually pleasing manner. It does a browser detect. So sue me.
*/

function fix_column_widths() {
    var agt = navigator.userAgent.toLowerCase();
    if ((agt.indexOf("msie") != -1) && (agt.indexOf("opera") == -1)) {
        fix_column_width('left-column');
        fix_column_width('right-column');
    }
}

function fix_column_width(colName) {
    if(column = document.getElementById(colName)) {
        if(!column.offsetWidth) {
            setTimeout("fix_column_width('" + colName + "')", 20);
            return;
        }

        var width = 0;
        var nodes = column.childNodes;

        for(i = 0; i < nodes.length; ++i) {
            if(nodes[i].className.indexOf("block") != -1 ) {
                if(width < nodes[i].offsetWidth) {
                    width = nodes[i].offsetWidth;
                }
            }
        }

        for(i = 0; i < nodes.length; ++i) {
            if(nodes[i].className.indexOf("block") != -1 ) {
                nodes[i].style.width = width + 'px';
            }
        }
    }
}


/*
   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);
}

function stripHTML(str) {
    var re = /<\S[^><]*>/g;
    var ret = str.replace(re, "");
    return ret;
}

function updateProgressBar(id, percent, msg, estimate) {
    var progressIndicator = Y.one('#' + id);
    if (!progressIndicator) {
        return;
    }

    var progressBar = progressIndicator.one('.bar'),
        statusIndicator = progressIndicator.one('h2'),
        estimateIndicator = progressIndicator.one('p');

    statusIndicator.set('innerHTML', Y.Escape.html(msg));
    progressBar.set('innerHTML', Y.Escape.html('' + percent + '%'));
    if (percent === 100) {
        progressIndicator.addClass('progress-success');
        estimateIndicator.set('innerHTML', null);
    } else {
        if (estimate) {
            estimateIndicator.set('innerHTML', Y.Escape.html(estimate));
        } else {
            estimateIndicator.set('innerHTML', null);
        }
        progressIndicator.removeClass('progress-success');
    }
    progressBar.setAttribute('aria-valuenow', percent);
    progressBar.setStyle('width', percent + '%');
}

// ===== Deprecated core Javascript functions for Moodle ====
//       DO NOT USE!!!!!!!
// Do not put this stuff in separate file because it only adds extra load on servers!

/**
 * @method show_item
 * @deprecated since Moodle 2.7.
 * @see Y.Node.show
 */
function show_item() {
    throw new Error('show_item can not be used any more. Please use Y.Node.show.');
}

/**
 * @method destroy_item
 * @deprecated since Moodle 2.7.
 * @see Y.Node.destroy
 */
function destroy_item() {
    throw new Error('destroy_item can not be used any more. Please use Y.Node.destroy.');
}

/**
 * @method hide_item
 * @deprecated since Moodle 2.7.
 * @see Y.Node.hide
 */
function hide_item() {
    throw new Error('hide_item can not be used any more. Please use Y.Node.hide.');
}

/**
 * @method addonload
 * @deprecated since Moodle 2.7 - please do not use this function any more.
 */
function addonload() {
    throw new Error('addonload can not be used any more.');
}

/**
 * @method getElementsByClassName
 * @deprecated Since Moodle 2.7 - please do not use this function any more.
 * @see Y.one
 * @see Y.all
 */
function getElementsByClassName() {
    throw new Error('getElementsByClassName can not be used any more. Please use Y.one or Y.all.');
}

/**
 * @method findChildNodes
 * @deprecated since Moodle 2.7 - please do not use this function any more.
 * @see Y.all
 */
function findChildNodes() {
    throw new Error('findChildNodes can not be used any more. Please use Y.all.');
}

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. It also selectable categories on or off.
 *
 * $form->init_javascript_enhancement('elementname','smartselect', array('selectablecategories'=>true|false, 'mode'=>'compact'|'spanning'));
 *
 * @param {YUI} Y
 * @param {string} id
 * @param {Array} options
 */
M.form.init_smartselect = function(Y, id, options) {
    if (!id.match(/^id_/)) {
        id = 'id_'+id;
    }
    var select = Y.one('select#'+id);
    if (!select) {
        return false;
    }
    Y.use('event-delegate',function(){
        var smartselect = {
            id : id,
            structure : [],
            options : [],
            submenucount : 0,
            currentvalue : null,
            currenttext : null,
            shownevent : null,
            cfg : {
                selectablecategories : true,
                mode : null
            },
            nodes : {
                select : null,
                loading : null,
                menu : null
            },
            init : function(Y, id, args, nodes) {
                if (typeof(args)=='object') {
                    for (var i in this.cfg) {
                        if (args[i] || args[i]===false) {
                            this.cfg[i] = args[i];
                        }
                    }
                }

                // Display a loading message first up
                this.nodes.select = nodes.select;

                this.currentvalue = this.nodes.select.get('selectedIndex');
                this.currenttext = this.nodes.select.all('option').item(this.currentvalue).get('innerHTML');

                var options = Array();
                options[''] = {text:this.currenttext,value:'',depth:0,children:[]};
                this.nodes.select.all('option').each(function(option, index) {
                    var rawtext = option.get('innerHTML');
                    var text = rawtext.replace(/^(&nbsp;)*/, '');
                    if (rawtext === text) {
                        text = rawtext.replace(/^(\s)*/, '');
                        var depth = (rawtext.length - text.length ) + 1;
                    } else {
                        var depth = ((rawtext.length - text.length )/12)+1;
                    }
                    option.set('innerHTML', text);
                    options['i'+index] = {text:text,depth:depth,index:index,children:[]};
                }, this);

                this.structure = [];
                var structcount = 0;
                for (var i in options) {
                    var o = options[i];
                    if (o.depth == 0) {
                        this.structure.push(o);
                        structcount++;
                    } else {
                        var d = o.depth;
                        var current = this.structure[structcount-1];
                        for (var j = 0; j < o.depth-1;j++) {
                            if (current && current.children) {
                                current = current.children[current.children.length-1];
                            }
                        }
                        if (current && current.children) {
                            current.children.push(o);
                        }
                    }
                }

                this.nodes.menu = Y.Node.create(this.generate_menu_content());
                this.nodes.menu.one('.smartselect_mask').setStyle('opacity', 0.01);
                this.nodes.menu.one('.smartselect_mask').setStyle('width', (this.nodes.select.get('offsetWidth')+5)+'px');
                this.nodes.menu.one('.smartselect_mask').setStyle('height', (this.nodes.select.get('offsetHeight'))+'px');

                if (this.cfg.mode == null) {
                    var formwidth = this.nodes.select.ancestor('form').get('offsetWidth');
                    if (formwidth < 400 || this.nodes.menu.get('offsetWidth') < formwidth*2) {
                        this.cfg.mode = 'compact';
                    } else {
                        this.cfg.mode = 'spanning';
                    }
                }

                if (this.cfg.mode == 'compact') {
                    this.nodes.menu.addClass('compactmenu');
                } else {
                    this.nodes.menu.addClass('spanningmenu');
                    this.nodes.menu.delegate('mouseover', this.show_sub_menu, '.smartselect_submenuitem', this);
                }

                Y.one(document.body).append(this.nodes.menu);
                var pos = this.nodes.select.getXY();
                pos[0] += 1;
                this.nodes.menu.setXY(pos);
                this.nodes.menu.on('click', this.handle_click, this);

                Y.one(window).on('resize', function(){
                     var pos = this.nodes.select.getXY();
                    pos[0] += 1;
                    this.nodes.menu.setXY(pos);
                 }, this);
            },
            generate_menu_content : function() {
                var content = '<div id="'+this.id+'_smart_select" class="smartselect">';
                content += this.generate_submenu_content(this.structure[0], true);
                content += '</ul></div>';
                return content;
            },
            generate_submenu_content : function(item, rootelement) {
                this.submenucount++;
                var content = '';
                if (item.children.length > 0) {
                    if (rootelement) {
                        content += '<div class="smartselect_mask" href="#ss_submenu'+this.submenucount+'">&nbsp;</div>';
                        content += '<div id="ss_submenu'+this.submenucount+'" class="smartselect_menu">';
                        content += '<div class="smartselect_menu_content">';
                    } else {
                        content += '<li class="smartselect_submenuitem">';
                        var categoryclass = (this.cfg.selectablecategories)?'selectable':'notselectable';
                        content += '<a class="smartselect_menuitem_label '+categoryclass+'" href="#ss_submenu'+this.submenucount+'" value="'+item.index+'">'+item.text+'</a>';
                        content += '<div id="ss_submenu'+this.submenucount+'" class="smartselect_submenu">';
                        content += '<div class="smartselect_submenu_content">';
                    }
                    content += '<ul>';
                    for (var i in item.children) {
                        content += this.generate_submenu_content(item.children[i],false);
                    }
                    content += '</ul>';
                    content += '</div>';
                    content += '</div>';
                    if (rootelement) {
                    } else {
                        content += '</li>';
                    }
                } else {
                    content += '<li class="smartselect_menuitem">';
                    content += '<a class="smartselect_menuitem_content selectable" href="#" value="'+item.index+'">'+item.text+'</a>';
                    content += '</li>';
                }
                return content;
            },
            select : function(e) {
                var t = e.target;
                e.halt();
                this.currenttext = t.get('innerHTML');
                this.currentvalue = t.getAttribute('value');
                this.nodes.select.set('selectedIndex', this.currentvalue);
                this.hide_menu();
            },
            handle_click : function(e) {
                var target = e.target;
                if (target.hasClass('smartselect_mask')) {
                    this.show_menu(e);
                } else if (target.hasClass('selectable') || target.hasClass('smartselect_menuitem')) {
                    this.select(e);
                } else if (target.hasClass('smartselect_menuitem_label') || target.hasClass('smartselect_submenuitem')) {
                    this.show_sub_menu(e);
                }
            },
            show_menu : function(e) {
                e.halt();
                var menu = e.target.ancestor().one('.smartselect_menu');
                menu.addClass('visible');
                this.shownevent = Y.one(document.body).on('click', this.hide_menu, this);
            },
            show_sub_menu : function(e) {
                e.halt();
                var target = e.target;
                if (!target.hasClass('smartselect_submenuitem')) {
                    target = target.ancestor('.smartselect_submenuitem');
                }
                if (this.cfg.mode == 'compact' && target.one('.smartselect_submenu').hasClass('visible')) {
                    target.ancestor('ul').all('.smartselect_submenu.visible').removeClass('visible');
                    return;
                }
                target.ancestor('ul').all('.smartselect_submenu.visible').removeClass('visible');
                target.one('.smartselect_submenu').addClass('visible');
            },
            hide_menu : function() {
                this.nodes.menu.all('.visible').removeClass('visible');
                if (this.shownevent) {
                    this.shownevent.detach();
                }
            }
        };
        smartselect.init(Y, id, options, {select:select});
    });
};

/** List of flv players to be loaded */
M.util.video_players = [];
/** List of mp3 players to be loaded */
M.util.audio_players = [];

/**
 * Add video player
 * @param id element id
 * @param fileurl media url
 * @param width
 * @param height
 * @param autosize true means detect size from media
 */
M.util.add_video_player = function (id, fileurl, width, height, autosize) {
    M.util.video_players.push({id: id, fileurl: fileurl, width: width, height: height, autosize: autosize, resized: false});
};

/**
 * Add audio player.
 * @param id
 * @param fileurl
 * @param small
 */
M.util.add_audio_player = function (id, fileurl, small) {
    M.util.audio_players.push({id: id, fileurl: fileurl, small: small});
};

/**
 * Initialise all audio and video player, must be called from page footer.
 */
M.util.load_flowplayer = function() {
    if (M.util.video_players.length == 0 && M.util.audio_players.length == 0) {
        return;
    }
    if (typeof(flowplayer) == 'undefined') {
        var loaded = false;

        var embed_function = function() {
            if (loaded || typeof(flowplayer) == 'undefined') {
                return;
            }
            loaded = true;

            var controls = {
                    autoHide: true
            }
            /* TODO: add CSS color overrides for the flv flow player */

            for(var i=0; i<M.util.video_players.length; i++) {
                var video = M.util.video_players[i];
                if (video.width > 0 && video.height > 0) {
                    var src = {src: M.cfg.wwwroot + '/lib/flowplayer/flowplayer-3.2.18.swf', width: video.width, height: video.height};
                } else {
                    var src = M.cfg.wwwroot + '/lib/flowplayer/flowplayer-3.2.18.swf';
                }
                flowplayer(video.id, src, {
                    plugins: {controls: controls},
                    clip: {
                        url: video.fileurl, autoPlay: false, autoBuffering: true, scaling: 'fit', mvideo: video,
                        onMetaData: function(clip) {
                            if (clip.mvideo.autosize && !clip.mvideo.resized) {
                                clip.mvideo.resized = true;
                                //alert("metadata!!! "+clip.width+' '+clip.height+' '+JSON.stringify(clip.metaData));
                                if (typeof(clip.metaData.width) == 'undefined' || typeof(clip.metaData.height) == 'undefined') {
                                    // bad luck, we have to guess - we may not get metadata at all
                                    var width = clip.width;
                                    var height = clip.height;
                                } else {
                                    var width = clip.metaData.width;
                                    var height = clip.metaData.height;
                                }
                                var minwidth = 300; // controls are messed up in smaller objects
                                if (width < minwidth) {
                                    height = (height * minwidth) / width;
                                    width = minwidth;
                                }

                                var object = this._api();
                                object.width = width;
                                object.height = height;
                            }
                        }
                    }
                });
            }
            if (M.util.audio_players.length == 0) {
                return;
            }
            var controls = {
                    autoHide: false,
                    fullscreen: false,
                    next: false,
                    previous: false,
                    scrubber: true,
                    play: true,
                    pause: true,
                    volume: true,
                    mute: false,
                    backgroundGradient: [0.5,0,0.3]
                };

            var rule;
            for (var j=0; j < document.styleSheets.length; j++) {

                // To avoid javascript security violation accessing cross domain stylesheets
                var allrules = false;
                try {
                    if (typeof (document.styleSheets[j].rules) != 'undefined') {
                        allrules = document.styleSheets[j].rules;
                    } else if (typeof (document.styleSheets[j].cssRules) != 'undefined') {
                        allrules = document.styleSheets[j].cssRules;
                    } else {
                        // why??
                        continue;
                    }
                } catch (e) {
                    continue;
                }

                // On cross domain style sheets Chrome V8 allows access to rules but returns null
                if (!allrules) {
                    continue;
                }

                for(var i=0; i<allrules.length; i++) {
                    rule = '';
                    if (/^\.mp3flowplayer_.*Color$/.test(allrules[i].selectorText)) {
                        if (typeof(allrules[i].cssText) != 'undefined') {
                            rule = allrules[i].cssText;
                        } else if (typeof(allrules[i].style.cssText) != 'undefined') {
                            rule = allrules[i].style.cssText;
                        }
                        if (rule != '' && /.*color\s*:\s*([^;]+).*/gi.test(rule)) {
                            rule = rule.replace(/.*color\s*:\s*([^;]+).*/gi, '$1');
                            var colprop = allrules[i].selectorText.replace(/^\.mp3flowplayer_/, '');
                            controls[colprop] = rule;
                        }
                    }
                }
                allrules = false;
            }

            for(i=0; i<M.util.audio_players.length; i++) {
                var audio = M.util.audio_players[i];
                if (audio.small) {
                    controls.controlall = false;
                    controls.height = 15;
                    controls.time = false;
                } else {
                    controls.controlall = true;
                    controls.height = 25;
                    controls.time = true;
                }
                flowplayer(audio.id, M.cfg.wwwroot + '/lib/flowplayer/flowplayer-3.2.18.swf', {
                    plugins: {controls: controls, audio: {url: M.cfg.wwwroot + '/lib/flowplayer/flowplayer.audio-3.2.11.swf'}},
                    clip: {url: audio.fileurl, provider: "audio", autoPlay: false}
                });
            }
        }

        if (M.cfg.jsrev == -1) {
            var jsurl = M.cfg.wwwroot + '/lib/flowplayer/flowplayer-3.2.13.js';
        } else {
            var jsurl = M.cfg.wwwroot + '/lib/javascript.php?jsfile=/lib/flowplayer/flowplayer-3.2.13.min.js&rev=' + M.cfg.jsrev;
        }
        var fileref = document.createElement('script');
        fileref.setAttribute('type','text/javascript');
        fileref.setAttribute('src', jsurl);
        fileref.onload = embed_function;
        fileref.onreadystatechange = embed_function;
        document.getElementsByTagName('head')[0].appendChild(fileref);
    }
};