var $ = function(id){ return document.getElementById(id); }
var iosDetected = navigator.userAgent.match("(iPad|iPod|iPhone)");
var timer = null;
var timerDelay = iosDetected ? 800 : 400;
var show = function(elem) { elem.style.display = "block" }
var $note, $action, $preview, $plain_password, $input_elems, $dashed_line, $proposed_title, updatePreview;
var firstLines_;
var backendTimer;

function updateProposedTitle() {
    clearTimeout(backendTimer);
    backendTimer = setTimeout(function () {
        var http = new XMLHttpRequest();
        var url = "/propose-title";
        http.open("POST", url, true);
        http.onreadystatechange = function() {
            if(http.readyState == 4 && http.status == 200) {
                var now = new Date();
                $proposed_title.innerHTML = 
        "Expected URL: https://www.notehub.org/" + 
        now.getFullYear() + "/" + (now.getMonth()+1) + "/" + now.getDate() + "/" +
        http.responseText;
            }
        }
        http.send($note.value);
    }, 500);
}

function md2html(input){
  return marked(input);
}

function onLoad () {
  $note = $("note");
  $action = $("action");
  $preview = $("preview");
  $plain_password = $("plain-password");
  $proposed_title = $("proposed-title");
  $input_elems = $("input-elems");
  $dashed_line = $("dashed-line");
  updatePreview = function(){
    clearTimeout(timer);
    var content = $note.value;
    var delay = Math.min(timerDelay, timerDelay * (content.length / 400));
    timer = setTimeout(function(){
      show($dashed_line);
      show($input_elems);
      $preview.innerHTML = md2html(content);
      var firstLines = content.split("\n", 2);
      if(firstLines_ != firstLines) {
          firstLines_ = firstLines;
          updateProposedTitle();
      }
    }, delay);
  };
  if($action){
    if($action.value == "update") updatePreview(); else $note.value = "";
    $note.onkeyup = updatePreview;
    $("publish-button").onclick = function(e) {
      if($plain_password.value != "") $("password").value = md5($plain_password.value);
      $plain_password.value = null;
      $("signature").value = md5($("session").value + $note.value);
    }
    if(iosDetected) $note.className += " ui-border"; else $note.focus();
  }
}