gmail scheduler

gmail-scheduler.gs

var label = 'schedule';

function dpad(num){
  if(num<10){
    return "0"+num;
  }else{
    return num;
  }
}

function gmail_scheduler() {
  // date2string
  var date = new Date();
  var dstr = '';
  dstr += date.getFullYear();
  
  dstr += dpad(date.getMonth()+1);
  dstr += dpad(date.getDate()) + '.';
  dstr += dpad(date.getHours());
  dstr += dpad(date.getMinutes());
  
  // getting the threads
  var threads = GmailApp.search('in:drafts label:'+label);
  var tlabel = GmailApp.getUserLabelByName(label);
  
  for(var i=0; i<threads.length; i++){
    var msgs = threads[i].getMessages();
    var unsent = 0;
    
    for(var j=0; j<msgs.length; j++){
      var msg = msgs[j];
      
      if(msg.isDraft()){
        unsent += 1;
        var sub = msg.getSubject();
        
        if(dstr>sub){
          sub = sub.split(' ').slice(1).join(' ');
          
          // cannot send, so we forward the message instead
          msg.forward(msg.getTo(), {
            cc: msg.getCc(),
            bcc: msg.getBcc(),
            subject: sub
          });
          
          // fix subject error when reply received
          Gmail.Users.Messages.remove('me', msg.getId());
        }
      }
    }
    
    if(unsent==0){
      threads[i].removeLabel(tlabel);
    }
  }
}