Chris@0: /**
Chris@0:  * @file
Chris@0:  * JavaScript API for the History module, with client-side caching.
Chris@0:  *
Chris@0:  * May only be loaded for authenticated users, with the History module enabled.
Chris@0:  */
Chris@0: 
Chris@0: (function ($, Drupal, drupalSettings, storage) {
Chris@0:   const currentUserID = parseInt(drupalSettings.user.uid, 10);
Chris@0: 
Chris@0:   // Any comment that is older than 30 days is automatically considered read,
Chris@0:   // so for these we don't need to perform a request at all!
Chris@0:   const secondsIn30Days = 2592000;
Chris@0:   const thirtyDaysAgo = Math.round(new Date().getTime() / 1000) - secondsIn30Days;
Chris@0: 
Chris@0:   // Use the data embedded in the page, if available.
Chris@0:   let embeddedLastReadTimestamps = false;
Chris@0:   if (drupalSettings.history && drupalSettings.history.lastReadTimestamps) {
Chris@0:     embeddedLastReadTimestamps = drupalSettings.history.lastReadTimestamps;
Chris@0:   }
Chris@0: 
Chris@0:   /**
Chris@0:    * @namespace
Chris@0:    */
Chris@0:   Drupal.history = {
Chris@0: 
Chris@0:     /**
Chris@0:      * Fetch "last read" timestamps for the given nodes.
Chris@0:      *
Chris@0:      * @param {Array} nodeIDs
Chris@0:      *   An array of node IDs.
Chris@0:      * @param {function} callback
Chris@0:      *   A callback that is called after the requested timestamps were fetched.
Chris@0:      */
Chris@0:     fetchTimestamps(nodeIDs, callback) {
Chris@0:       // Use the data embedded in the page, if available.
Chris@0:       if (embeddedLastReadTimestamps) {
Chris@0:         callback();
Chris@0:         return;
Chris@0:       }
Chris@0: 
Chris@0:       $.ajax({
Chris@0:         url: Drupal.url('history/get_node_read_timestamps'),
Chris@0:         type: 'POST',
Chris@0:         data: { 'node_ids[]': nodeIDs },
Chris@0:         dataType: 'json',
Chris@0:         success(results) {
Chris@0:           Object.keys(results || {}).forEach((nodeID) => {
Chris@0:             storage.setItem(`Drupal.history.${currentUserID}.${nodeID}`, results[nodeID]);
Chris@0:           });
Chris@0:           callback();
Chris@0:         },
Chris@0:       });
Chris@0:     },
Chris@0: 
Chris@0:     /**
Chris@0:      * Get the last read timestamp for the given node.
Chris@0:      *
Chris@0:      * @param {number|string} nodeID
Chris@0:      *   A node ID.
Chris@0:      *
Chris@0:      * @return {number}
Chris@0:      *   A UNIX timestamp.
Chris@0:      */
Chris@0:     getLastRead(nodeID) {
Chris@0:       // Use the data embedded in the page, if available.
Chris@0:       if (embeddedLastReadTimestamps && embeddedLastReadTimestamps[nodeID]) {
Chris@0:         return parseInt(embeddedLastReadTimestamps[nodeID], 10);
Chris@0:       }
Chris@0:       return parseInt(storage.getItem(`Drupal.history.${currentUserID}.${nodeID}`) || 0, 10);
Chris@0:     },
Chris@0: 
Chris@0:     /**
Chris@0:      * Marks a node as read, store the last read timestamp client-side.
Chris@0:      *
Chris@0:      * @param {number|string} nodeID
Chris@0:      *   A node ID.
Chris@0:      */
Chris@0:     markAsRead(nodeID) {
Chris@0:       $.ajax({
Chris@0:         url: Drupal.url(`history/${nodeID}/read`),
Chris@0:         type: 'POST',
Chris@0:         dataType: 'json',
Chris@0:         success(timestamp) {
Chris@0:           // If the data is embedded in the page, don't store on the client
Chris@0:           // side.
Chris@0:           if (embeddedLastReadTimestamps && embeddedLastReadTimestamps[nodeID]) {
Chris@0:             return;
Chris@0:           }
Chris@0: 
Chris@0:           storage.setItem(`Drupal.history.${currentUserID}.${nodeID}`, timestamp);
Chris@0:         },
Chris@0:       });
Chris@0:     },
Chris@0: 
Chris@0:     /**
Chris@0:      * Determines whether a server check is necessary.
Chris@0:      *
Chris@0:      * Any content that is >30 days old never gets a "new" or "updated"
Chris@0:      * indicator. Any content that was published before the oldest known reading
Chris@0:      * also never gets a "new" or "updated" indicator, because it must've been
Chris@0:      * read already.
Chris@0:      *
Chris@0:      * @param {number|string} nodeID
Chris@0:      *   A node ID.
Chris@0:      * @param {number} contentTimestamp
Chris@0:      *   The time at which some content (e.g. a comment) was published.
Chris@0:      *
Chris@0:      * @return {bool}
Chris@0:      *   Whether a server check is necessary for the given node and its
Chris@0:      *   timestamp.
Chris@0:      */
Chris@0:     needsServerCheck(nodeID, contentTimestamp) {
Chris@0:       // First check if the content is older than 30 days, then we can bail
Chris@0:       // early.
Chris@0:       if (contentTimestamp < thirtyDaysAgo) {
Chris@0:         return false;
Chris@0:       }
Chris@0: 
Chris@0:       // Use the data embedded in the page, if available.
Chris@0:       if (embeddedLastReadTimestamps && embeddedLastReadTimestamps[nodeID]) {
Chris@0:         return contentTimestamp > parseInt(embeddedLastReadTimestamps[nodeID], 10);
Chris@0:       }
Chris@0: 
Chris@0:       const minLastReadTimestamp = parseInt(storage.getItem(`Drupal.history.${currentUserID}.${nodeID}`) || 0, 10);
Chris@0:       return contentTimestamp > minLastReadTimestamp;
Chris@0:     },
Chris@0:   };
Chris@0: }(jQuery, Drupal, drupalSettings, window.localStorage));