meteor__coursera-meteor-2/textcircle.js

// This collection stores all the documents.
// Note: not Documents, but this.Documents, because of the editing package (?)
this.Documents = new Mongo.Collection("documents");
// This collection stores sets of users that are editing documents.
EditingUsers = new Mongo.Collection("editingUsers");

if (Meteor.isClient) {
  Template.editor.helpers({
    // Return the id of the first document you can find.
    docid: function () {
      const doc = Documents.findOne();
      return doc ? doc._id : undefined;
    },
    // Configure the CodeMirror editor.
    config: function () {
      return function (editor) {
        editor.setOption("lineNumbers", true);
        editor.setOption("mode", "html");
        // Set a callback that gets triggered whenever the user
        // makes a change in the code editing window.
        editor.on("change", function (cmEditor /* , info */) {
          let $preview = $("#viewer_iframe");
          // Send the current code over to the iframe for rendering.
          $preview.contents().find("html").html(cmEditor.getValue());
          Meteor.call("addEditingUser");
        });
      };
    }
  });

  Template.editingUsers.helpers({
    // Retrieve a set of users that are editing this document.
    users: function () {
      let doc = Documents.findOne();
      if (!doc) {
        // Give up.
        return null;
      }
      let eUsers = EditingUsers.findOne({ docId: doc._id });
      if (!eUsers) {
        // Give up.
        return null;
      }
      let users = new Array();
      let i = 0;
      for (let userId in eUsers.users) {
        users[i] = fixObjectsKeys(eUsers.users[userId]);
        users[i]._id = userId;
        i++;
      }
      return users;
    }
  });
} // end isClient...

if (Meteor.isServer) {
  Meteor.startup(function () {
    // Insert a document if there isn't one already.
    if (!Documents.findOne()) {
      Documents.insert({ title: "my new document" });
    }
  });
}

// Methods that provide write access to the data.
Meteor.methods({
  addEditingUser: function () {
    let doc = Documents.findOne();
    if (!doc) {
      // No doc: give up.
      return;
    }
    if (!this.userId) {
      // No logged-in user: give up.
      return;
    }
    // Now I have a doc and possibly a user.
    let user = Meteor.user().profile;
    let eUsers = EditingUsers.findOne({ docId: doc._id });
    // No editing users have been stored yet.
    if (!eUsers) {
      eUsers = {
        docId: doc._id,
        users: {}
      };
    }
    user.lastEdit = new Date();
    eUsers.users[this.userId] = user;
    // Upsert: insert or update if filter matches.
    EditingUsers.upsert({ _id: eUsers._id }, eUsers);
  }
});

// This renames object keys by removing hyphens to make them compatible
// with spacebars.
function fixObjectsKeys(obj) {
  let newObj = {};
  for (let key in obj) {
    if (obj.hasOwnProperty(key)) {
      const key2 = key.replace("-", "");
      newObj[key2] = obj[key];
    }
  }
  return newObj;
}