const useCapture = false; // capture, bubbling: false

button = document.getElementsByTagName('button')[0];
button.addEventListener('click',genesis,false);
console.log(button)
var payload = 'QmVnvdASdT1c9fJ2mcDhTAYhb63gcFRkiRmJW7NAm1YcSf';
//var txcoinhash = 'ZCBtx7Wg59hvMogWDchKVcGUMo68qDe2dkRfzaskAh3G';
//var prevhash = 'Z9BEeWD4Mww7yrXyPRXrfM2y6FxsQGfaNPzC8DxWq4ATq';
var pow = '11501558695957493006';
var comment = 'Genesis ~ Manuela J. Savina';

// get default values (from nodes) ...
let promised_config = fetch(api_url + 'config').
  then(resp => resp.json()).
  then(obj => { return obj.config }).
  catch(console.error)

let promised_nullhash = fetch(api_url + 'getjson?obj=Genesis::nullhash').
  then(resp => resp.json()).
  then(obj => { console.log('promised_nullhash.obj:',obj)
    return obj;
  }).
  catch(console.error);

Promise.all([promised_config, promised_nullhash]).then( _ => {
  let [config,nullhash] = _;
  console.log('genesis.config:',config);
  document.getElementsByName('payload')[0].value = payload;
  document.getElementsByName('txcoinhash')[0].value = config.txcoin;
  document.getElementsByName('prevhash')[0].value = nullhash;
  document.getElementsByName('pow')[0].value = pow;
  document.getElementsByName('comment')[0].value = comment;
}).catch(console.error);


function genesis(ev) {
  console.log('genesis.ev: %o',ev);
  let query = {
    "payload": document.getElementsByName('payload')[0].value,
    "txcoin": document.getElementsByName('txcoinhash')[0].value,
    "bkprev": document.getElementsByName('prevhash')[0].value,
    "pow": document.getElementsByName('pow')[0].value,
    "comment": document.getElementsByName('comment')[0].value
  };
  query_string = Object.keys(query).map( k => k +'='+ query[k] ).join('&');
  let url = api_url + `creategen?${query_string}`;
  document.getElementByName('pow')[0].value = 'working...';
  let promised = fetch(url).
  then(resp => resp.json()).
  then(obj => {
    console.log('genesis.obj:',obj);
    document.getElementsByName('pow')[0].value = obj.pow;
  }).
  catch(console.error);
}