// Search Google Voicemail emails
function searchGoogleVoiceEmails() {
  var threads = GmailApp.search('from:voice-noreply@google.com', 0, 100);

  for (var t = 0; t < threads.length; t++) {
    var response = extractVoicemail_(threads[t].getMessages()[0]);

    if (response) {
      createContact_(response);
    }
  }
}

// Extract the caller's name, phone number and voice message transcription
function extractVoicemail_(msg) {
  var result = {
    'Message Date': msg.getDate(),
    'Message Subject': msg.getSubject(),
    'Message Body': msg
      .getPlainBody()
      .replace(/<[^>]+>/g, '')
      .replace(/\s+/g, ' '),
    Transcription: msg.getPlainBody(),
  };

  var trans = /transcript:(.*)?play message/i.exec(result['Message Body']);

  if (trans) result.Transcription = trans[1];

  //Voicemail from: John Q Public (202) 123-456 at 6:08 PM

  var match = /(Missed Call|Voicemail) from:([*\+\s\w]+)([\d\-\s\(\)\+]*)? at [\d\:\s]+[ap]m/i.exec(
    result['Message Body']
  );

  if (match) {
    result['Call Type'] = match[1];
    result['Contact Name'] = match[2].replace(/^+/, '');
    result['Contact Number'] = match[3].replace(/^+/, '');
  } else {
    return null;
  }

  return result;
}

// Create a new Google contact from Voicemail
function createContact_(result) {
  var contacts = ContactsApp.getContactsByPhone(result['Contact Number'], ContactsApp.Field.WORK_PHONE);

  if (contacts.length > 0) {
    return 'Contact Exists';
  } else {
    var contact = ContactsApp.createContact(result['Contact Name'], result['Contact Name'], result['Call Type']);

    contact.addPhone(ContactsApp.Field.WORK_PHONE, result['Contact Number']);
    contact.setNotes(result['Transcription']);

    return contact.getId();
  }
}