gocodebox/lifterlms

/* global LLMS, $ */

/**
 * User event/interaction tracking.
 *
 * @since 3.36.0
 * @since 3.36.2 Fix JS error when settings aren't loaded.
 * @since 3.37.2 When adding an event to the storae also make sure the nonce is set for server-side verification.
 * @since 3.37.9 Fix IE compatibility issue related to usage of `Object.assign()`.
 * @since 3.37.14 Persist the tracking events via ajax when reaching the cookie size limit.
 * @since 5.0.0 Set `settings` as an empty object when no settings supplied.
 * @since 7.1.0 Only attempt to add a nonce to the datastore when a nonce exists in the settings object.
 */
LLMS.Tracking = function( settings ) {

    settings = settings || {};

    var self = this,
        store = new LLMS.Storage( 'llms-tracking' );

    settings = 'string' === typeof settings ? JSON.parse( settings ) : settings;

    /**
     * Initialize / Bind all tracking event listeners.
     *
     * @since 3.36.0
     * @since 5.0.0 Only attempt to add a nonce to the datastore when a nonce exists in the settings object.
     * @since 7.1.0 Do not add a nonce to the datastore by default, will be added/updated
     *              when storing an event to track.
     *
     * @return {void}
     */
    function init() {

        self.addEvent( 'page.load' );

        window.addEventListener( 'beforeunload', onBeforeUnload );
        window.addEventListener( 'unload', onUnload );

        document.addEventListener( 'visibilitychange', onVisibilityChange );

    };

    /**
     * Add an event.
     *
     * @since 3.36.0
     * @since 3.36.2 Fix error when settings aren't loaded.
     * @since 3.37.2 Always make sure the nonce is set for server-side verification.
     * @since 3.37.14 Persist the tracking events via ajax when reaching the cookie size limit.
     * @since 7.1.0 Only attempt to add a nonce to the datastore when a nonce exists in the settings object.
     *
     * @param string|obj event Event Id (type.event) or a full event object from `this.makeEventObj()`.
     * @param int args Optional additional arguments to pass to `this.makeEventObj()`.
     * @return {void}
     */
    this.addEvent = function( event, args ) {

        args  = args || {};
        if ( 'string' === typeof event ) {
            args.event = event;
        }

        // If the event isn't registered in the settings don't proceed.
        if ( !settings.events || -1 === settings.events.indexOf( args.event ) ) {
            return;
        }

        // Make sure the nonce is set for server-side verification.
        if ( settings.nonce ) {
            store.set( 'nonce', settings.nonce );
        }

        event = self.makeEventObj( args );

        var all = store.get( 'events', [] );
        all.push( event );
        store.set( 'events', all );

        // If couldn't store the latest event because of size limits.
        if ( all.length > store.get( 'events', [] ).length ) {

            // Copy the cookie in a temporary variable.
            var _temp = store.getAll();
            // Clear the events from the cookie.
            store.clear('events');

            // Add the latest event to the temporary variable.
            _temp['events'].push( event );

            // Send the temporary variable as string via ajax.
            LLMS.Ajax.call( {
                data: {
                    action: 'persist_tracking_events',
                    'llms-tracking': JSON.stringify(_temp)
                },

                error: function( xhr, status, error ) {

                    console.log( xhr, status, error );

                },
                success: function( r ) {

                    if ( 'error' === r.code ) {
                        console.log(r.code, r.message);
                    }

                }

            } );

        }

    }

    /**
     * Retrieve initialization settings.
     *
     * @since 3.36.0
     *
     * @return obj
     */
    this.getSettings = function() {
        return settings;
    }

    /**
     * Create an event object suitable to save as an event.
     *
     * @since 3.36.0
     * @since 3.37.9 Use `$.extend()` in favor of `Object.assign()`.
     *
     * @param obj event {
     *     Event hash
     *
     *     @param {string} event (Required) Event ID, eg: "page.load".
     *     @param {url} url Event URL. (Optional, added automatically) Stored as metadata and used to infer an object_id for post events.
     *     @param {time} float (Optional, added automatically) Timestamp (in milliseconds). Used for the event creation date.
     *     @param {int} obj_id (Optional). The object ID. Inferred automatically via `url` if not provided.
     *     @param {obj} meta (Optional) Hash of metadata to store with the event.
     * }
     * @return obj
     */
    this.makeEventObj = function( event ) {
        return $.extend( event, {
            url: window.location.href,
            time: Math.round( new Date().getTime() / 1000 ),
        } );
    }


    /**
     * Remove the visibility change event listener on window.beforeunload
     *
     * Prevents actual unloading from recording a blur event from the visibility change listener
     *
     * @param obj e JS event object.
     * @return void
     */
    function onBeforeUnload( e ) {
        document.removeEventListener( 'visibilitychange', onVisibilityChange );
    }

    /**
     * Record a `page.exit` event on window.unload.
     *
     * @since 3.36.0
     *
     * @param obj e JS event object.
     * @return void
     */
    function onUnload( e ) {
        self.addEvent( 'page.exit' );
    }

    /**
     * Record `page.blur` and `page.focus` events via document.visilibitychange events.
     *
     * @since 3.36.0
     *
     * @param obj e JS event object.
     * @return void
     */
    function onVisibilityChange( e ) {

        var event = document.hidden ? 'page.blur' : 'page.focus';
        self.addEvent( event );

    }

    // Initialize on the frontend only.
    if ( ! $( 'body' ).hasClass( 'wp-admin' ) ) {
        init();
    }

};

llms.tracking = new LLMS.Tracking( llms.tracking );