console.clear();

function makeCreateFormCall(fields, callback, api_key) {
  function reqListener () {
    var response = JSON.parse(this.responseText);
    var form_link = response.links.form_render.get;
    callback(form_link, response);
  }

  var oReq = new XMLHttpRequest();
  oReq.onload = reqListener;
  oReq.open("POST", "https://api.typeform.io/v0.1/forms", true);

  oReq.setRequestHeader("X-API-TOKEN", api_key); 

  var form = {
    title: "Created from Typeform library",
    fields: fields
  };

  oReq.send(JSON.stringify(form));
}

function createIframe(link, element) { 
   ifrm = document.createElement("IFRAME"); 
   ifrm.setAttribute("src", link); 
   ifrm.style.width = 640+"px"; 
   ifrm.style.height = 480+"px"; 
   element.appendChild(ifrm); 
}

var Typeform = function(api_key) {
  if(api_key === undefined) {
    throw new Error("You need to provide a API-key as the first argument");
  }
  this.api_key = api_key;
};

Typeform.prototype = {
  createForm: function(selector, fields) {
    var element = document. querySelector (selector);
    makeCreateFormCall(fields, function(link) {
       createIframe(link, element);
    }, this.api_key);
  }
};

var typeform_instance = new Typeform('8a280cd49ae26a7dd78caa4c13e6460d');

typeform_instance.createForm('#form_here', [
  {
    type: "yes_no",
    question: "Hello there"
  }
]);