/*
*
*    _____ __   _                     
*   / ___// /__(_)___  ________  _____
*   \__ \/ //_/ / __ \/ ___/ _ \/ ___/
*  ___/ / ,< / / /_/ (__  )  __/ /    
* /____/_/|_/_/ .___/____/\___/_/     
*            /_/                      
*
*   For Usage Details, Refer This Page -
*   http://www.skipser.com/495
*
*/

var ALL_TEMPLATES;
var MSG;
var loadingImg = 'https://lh6.googleusercontent.com/-S87nMBe6KWE/TuB9dR48F0I/AAAAAAAAByQ/0Z96LirzDqg/s27/load.gif';

function doGet(e) {
  var key=e.parameter.key;
  checkdb(key);
}


function Run() {
  ALL_TEMPLATES = GmailApp.search("in:drafts");
  var app = UiApp.createApplication().setTitle('Selezionare il messaggio per la conferma di lettura.');
  var mainPanel = app.createVerticalPanel().setId('mainPanel');
  var button = app.createButton('Invia');

  var listBox = app.createListBox().setId('myLbId').setName('myLbName').setWidth(300);
  listBox.addItem('Selezionare...');
  var max_drafts=5;
  if(ALL_TEMPLATES.length < 5) {
    max_drafts=ALL_TEMPLATES.length;
  }
  for (var i = 0; i < max_drafts; i++) {
    var msgs = ALL_TEMPLATES[i].getMessages();
    var msg = msgs[0];
    listBox.addItem(msgs[0].getSubject());
  }
  
  var img = app.createImage(loadingImg).setId("Loading").setVisible(false);
  var label = app.createLabel("Invio in corso.").setId("LoadingLabel").setVisible(false)
  
  mainPanel.add(listBox);
  mainPanel.add(button);
  mainPanel.add(label);
  mainPanel.add(img);
  
  var handler = app.createServerClickHandler('draftSelected').addCallbackElement(mainPanel);
  button.addClickHandler(handler);
  
  var chandler =app.createClientHandler().forEventSource().setEnabled(false).forTargets(img).setVisible(true).forTargets(label).setVisible(true);
  button.addClickHandler(chandler);
  
  app.add(mainPanel);
  SpreadsheetApp.getActiveSpreadsheet().show(app);
}
function draftSelected(eventInfo) {
  ALL_TEMPLATES = GmailApp.search("in:drafts");
  var app = UiApp.getActiveApplication();

  var max_drafts=5;
  if(ALL_TEMPLATES.length < 5) {
    max_drafts=ALL_TEMPLATES.length;
  }
  
  var value = eventInfo.parameter.myLbName;
  for (var i=0; i<max_drafts; i++) {
    var msgs=ALL_TEMPLATES[i].getMessages();
    if (msgs[0].getSubject() == value) {
      MSG=msgs[0];
    }
  }
  if(MSG == null) {
   app.close();
    Browser.msgBox("Non è stato selezionato alcun messaggio. Riprovare.");
  }
  var atts = MSG.getAttachments();
  var newatts=[];
  for (var i=0; i< atts.length; i++) {
    var att = {
      mimeType:atts[i].getContentType(),
      fileName:atts[i].getName(), 
      content:atts[i].getBytes()
    };
    newatts.push(att);
  }
  
  var uniqkey=Utilities.formatDate(new Date(), "UTC", "yyMMddHHmmssSSS");
  storeindb(MSG.getFrom(),MSG.getTo(),MSG.getSubject(),uniqkey)
  var tracker="<img src='"+ ScriptApp.getService().getUrl() + "?key=" +uniqkey+ "' border='0' width='0'/>"; 
  
  GmailApp.sendEmail(
    MSG.getTo(),
    MSG.getSubject(),
    "", 
    { 
      htmlBody: MSG.getBody() + "\n"+tracker,
      attachments: newatts,
      cc:MSG.getCc(),
      bcc:MSG.getBcc()
    }
  );
  
  MSG.moveToTrash();
  
  app.getElementById("LoadingLabel").setVisible(false);
  app.getElementById("Loading").setVisible(false);
  app.close();
  
  Browser.msgBox("Fatto!!", "Mail inviata con successo", Browser.Buttons.OK);
  return app;
}


function storeindb(from,to,subject,key) {
  var date = Utilities.formatDate(new Date(), Session.getTimeZone(), "dd-MMM-yyyy, HH:mm:ss");
  var ob={key: key, email:{subject:subject, from:from,to:to, date:date}};
  var db = ScriptDb.getMyDb();
  
  var result = db.query({key: key});
  try  {
    if(!result.hasNext())  {
      var stored = db.save(ob);
      return 1;
    }
    else {
      Browser.msgBox("ERROR - La chiave " + key + " esiste già, riprovare");
      throw "ERROR: Chiave esistente";
    }
  }
  catch(e)  {
    Browser.msgBox("Errore memorizzazione database. " + e.toString())
    throw("ERROR: Errore memorizzazione dati.");
  }
}

function checkdb(key) {
  var local_key=key;  
  var db = ScriptDb.getMyDb();
  var result = db.query({key: local_key});
  
  if(result.hasNext())  {
    var current = result.next();
    
    var to=current.email.to;
    var totmp = to.replace(/(<([^>]+)>)/ig,"");
    var totmp1=totmp.replace(/ /ig, "");
    if(totmp1 != "") {
      to=totmp;
    }
    
    var subject = to + " ha letto la tua mail - " +current.email.subject;
    var message = to + " ha letto il seguente messaggio:<br/><br/>\n\n" +
      "Subject: " + current.email.subject + "<br/>\n"+
      "Sent:" + current.email.date + "<br/><br/>\n";
    
    if(current.email.from != "") {
      MailApp.sendEmail(current.email.from, 
                        subject,
                        "",
                        {
                          htmlBody:message
                        });
    }
    db.remove(current);
  }
  else {
    //do nothing
  }
}

function viewDb() {
  var db = ScriptDb.getMyDb();
  var result = db.query({}); 
  
  while (result.hasNext()) {
    var ob= result.next();
    Logger.log(ob.key + " " + ob.email.subject + ob.email.to + ob.email.date);
  }
}

function emptyDb() {
  var db = ScriptDb.getMyDb();
  while (true) {
    var result = db.query({}); 
    if (result.getSize() == 0) {
      break;
    }
    while (result.hasNext()) {
      db.remove(result.next());
    }
  }
}



function onOpen() {
    var ss = SpreadsheetApp.getActiveSpreadsheet();
    var menuEntries = [ {name: "Inizializza", functionName: "Initialize"},
                        {name: "Invia con conferma di lettura", functionName: "Run"}];
    ss.addMenu("Conferma di lettura", menuEntries);
}

function onInstall() {
  onOpen();
}

function Initialize() {
  return;
}