/*

  ======================================
  Who Can See Your Files in Google Drive
  ======================================

  Written by Amit Agarwal on 01/11/2014
  Tutorial :: http://labnol.org/?p=28237

*/

function ScanGoogleDrive() {
  var files = DriveApp.getFiles();
  var timezone = Session.getScriptTimeZone();
  var email = Session.getActiveUser().getEmail();

  var file, date, access, url, permission;
  var privacy, view, viewers, edit, editors;

  var rows = [['File Name', 'Who has access?', 'Date Created']];

  while (files.hasNext()) {
    file = files.next();

    try {
      access = file.getSharingAccess();
      permission = file.getSharingPermission();
      viewers = file.getViewers();
      editors = file.getEditors();

      view = [];
      edit = [];

      date = Utilities.formatDate(file.getDateCreated(), timezone, 'yyyy-MM-dd HH:mm');
      url = '<a href="' + file.getUrl() + '">' + file.getName() + '</a>';

      for (var v = 0; v < viewers.length; v++) {
        view.push(viewers[v].getName() + ' ' + viewers[v].getEmail());
      }

      for (var ed = 0; ed < editors.length; ed++) {
        edit.push(editors[ed].getName() + ' ' + editors[ed].getEmail());
      }

      switch (access) {
        case DriveApp.Access.PRIVATE:
          privacy = 'Private';
          break;
        case DriveApp.Access.ANYONE:
          privacy = 'Anyone';
          break;
        case DriveApp.Access.ANYONE_WITH_LINK:
          privacy = 'Anyone with a link';
          break;
        case DriveApp.Access.DOMAIN:
          privacy = 'Anyone inside domain';
          break;
        case DriveApp.Access.DOMAIN_WITH_LINK:
          privacy = 'Anyone inside domain who has the link';
          break;
        default:
          privacy = 'Unknown';
      }

      switch (permission) {
        case DriveApp.Permission.COMMENT:
          permission = 'can comment';
          break;
        case DriveApp.Permission.VIEW:
          permission = 'can view';
          break;
        case DriveApp.Permission.EDIT:
          permission = 'can edit';
          break;
        default:
          permission = '';
      }

      view = view.join(', ');

      edit = edit.join(', ');

      privacy +=
        (permission === '' ? '' : ' ' + permission) +
        (edit === '' ? '' : ', ' + edit + ' can edit') +
        (view === '' ? '' : ', ' + view + ' can view');

      rows.push([url, privacy, date]);
    } catch (e) {
      Logger.log(e.toString());
      Logger.log(file.getName());
    }
  }

  var html = '<p>File Permissions Report for Google Drive</p>';

  html += '<table><tr><td><b>' + rows[0].join('</b></td><td><b>') + '</b></td></tr>';

  for (var i = 1; i < rows.length; i++) {
    html += '<tr><td>' + rows[i].join('</td><td>') + '</td></tr>';
  }

  html +=
    "</table><br>For help, refer to this <a href='http://www.labnol.org/internet/google-drive-access/28237/'>online tutorial</a> written by <a href='https://ctrlq.org/'>Amit Agarwal</a>.";

  MailApp.sendEmail(email, 'Google Drive - File Permissions Report', '', { htmlBody: html });
}