add_book.js

let t = `title: {{title}}{{#subtitle}}
subtitle: {{subtitle}}{{/subtitle}}
author: {{authors}}
publisher: {{publisher}}
year: {{publishedDate}}
identifier: {{identifier}}
id: {{id}}
`

let template = MustacheTemplate.createWithTemplate(t);

var findBooks = function(reference) {
  let items = searchGoogleBooks(reference);
  if (items) {
    if (items.length > 3) {
      return items.slice(0, 3);
    }
    else {
      return items
    }
  }
}

var googleBooks = Prompt.create();

googleBooks.addLabel("title", "Search Google Books...");

googleBooks.addTextField("q", "🔎", "")
googleBooks.addButton("Confirm", 1, true);

googleBooks.show();

if (googleBooks.buttonPressed == 1) {

  var search = findBooks(googleBooks.fieldValues["q"]);
  let bookTitles = search.map((b) => md_mla_citation(b.volumeInfo));

  var bookSelect = Prompt.create();

  bookSelect.addLabel("title", "Choose a match:");

  bookSelect.addSelect(
    "selectBook",
    "Book:",
    bookTitles,
    [],
    false);

  bookSelect.addButton("Create Booknote", 1, true);

  bookSelect.show();

  if (bookSelect.buttonPressed == 1) {
    let d = Draft.create();
    book =
      search.find(b =>
        md_mla_citation(b.volumeInfo) == bookSelect.fieldValues["selectBook"]).volumeInfo;

    book.identifier = book.industryIdentifiers[0].identifier;
    book.id = zk_id(d);
    d.content = template.render(book);
    d.addTag("booknote");
    d.update();
  }
}

book_utilties.js

var mla_authors = function(authors) {
  switch (authors.length) {
    case 1: return authors[0]; break;
    case 2: return authors.join(", "); break;
    case 3: return authors[0] + " et al."; break;
  }
}

// Takes a string, returns the year
var mla_date = function(d) {
  let date = new Date(d);
  return date.getFullYear();
}

var md_mla_citation = function(data) {
  return `${mla_authors(data.authors)}. _${data.title}_. ${data.publisher}, ${mla_date(data.publishedDate)}.`
}

var searchGoogleBooks = function(query) {
  var url = "https://www.googleapis.com/books/v1/volumes?q=" + encodeURIComponent(query);

  var http = HTTP.create(); //create HTTP object
  var response = http.request({
    "url": url,
    "method": "GET"
  });

  if (response.success) {
    var jsonObj = JSON.parse(response.responseText);
    return jsonObj.items;
  } else {
    return null;
  }
}

link_to_book.js

let workspace = Workspace.find("Booknotes");
let booknotes = workspace.query("inbox");

let bookTitles = [];
for (let booknote of booknotes) {
  bookTitles.push(booknote.title.replace("title: ", ""));
}

var p = Prompt.create();

p.addLabel("title", "Choose booknote:");

p.addSelect(
  "selectBook",
  "Book:",
  bookTitles,
  [],
  false);

p.addButton("Choose Book", 1, true);

p.show();

if (p.buttonPressed == 1) {

  let bookIndex = booknotes.findIndex(bk => bk.title.includes(p.fieldValues["selectBook"]));
  let book = booknotes[bookIndex];

  // - Adds a citation to the book to the current note.
  let book_data = {};
  book_data.authors = [zk_get_metadata(book, "author")]
  book_data.title = zk_get_metadata(book, "title");
  book_data.publisher = zk_get_metadata(book, "publisher");
  book_data.publishedDate = zk_get_metadata(book, "year");

  draft.content = draft.content + `\n\n${md_mla_citation(book_data)}`;

  // - Links the current note to the ID of the booknote.
  draft.content = draft.content + `\n[[${zk_id(book)}]] ${zk_title(book)}`
  draft.addTag("booknote");
  draft.update();

  // - Adds a link to this zettel in the main booknote, if there’s a title, uses that as a summary
  book.content = book.content + `\n[[${zk_id(draft)}]] ${zk_title(draft)}`
  book.update();
}

mla.js

var findBook = function(reference) {
  let items = searchGoogleBooks(reference);
  if (items) {
    return md_mla_citation(items[0].volumeInfo);
  } else {
    return reference;
  }
}

if (editor.getSelectedRange()[1] != 0) {
  // we've selected some lines.
  var result =
    editor
    .getTextInRange(...editor.getSelectedLineRange())
    .split("\n")
    .map(ref => (ref.match(/#/)) ? ref : findBook(ref))
    .join("\n");

  editor.setTextInRange(...editor.getSelectedLineRange(), result);
}

draft.update();