function setProp(t, n, v) {
  if (isCProp(n)) return
  else if (n === 'className') t.setAttribute('class', v);
  else if (typeof value === 'boolean') setBProp(t, n, v);
  else t.setAttribute(n, v);
}

function unsetProp(t, n, v) {
  if (isCProp(n)) return;
  else if (n === 'className') t.removeAttribute('class');
  else if (typeof value === 'boolean') unsetBProp(t, n);
  else t.removeAttribute(n);
}


function setBProp(t, n, v) {
  if (v) t.setAttribute(n, v);
  t[n] = !!v;
}


function unsetBProp(t, n) {
  t.removeAttribute(n);
  t[n] = false;
}


function isCProp(n) {
  return isEProp(n) || name === 'forceUpdate';
}


function isEProp(n) {
  return /^on/.test(name);
}


function addEListeners(t, p) {
  Object.keys(p).filter(isEProp).forEach(n => t.addEventListener(n.slice(2).toLowerCase(), p[name]));
}


function setProps(t, p) {
  Object.keys(p).forEach(n => setProp(t, n, p[n]));
}


function updateProp(t, n, nv, ov) {
  if (!nv) unsetProp(t, n, ov);
  else if(!ov || nv !== ov) setProp(t, n, nv);
}


function updateProps(t, n, o = {}) {
  const p = Object.assign({}, n, o);
  Object.keys(p).forEach(nm => updateProp(t, nm, n[nm], o[nm]);
}


function createElement(n) {
  if (typeof node === 'string') return document.createTextNode(n);
  const e = document.createElement(n.type);
  setProps(e, n.props);
  addEListeners(e, n.props);
  n.children.map(createElement).forEach(e.appendChild.bind(e));
  return e;
}


function changed(n, o) {
  return typeof n !== typeof o || typeof n === 'string' && n !== o || n.type !== o.type || n.props.forceUpdate;
}


function updateElement(p, n, o, i=0) {
  if (!o) p.appendChild(createElement(n));
  else if (!n) p.removeChild(p.childNodes[i]);
  else if (changed(n, o)) p.replaceChild(createElement(n), p.childNodes[i]);
  else if (n.type) {
    updateProps(p.childNode[i], n.props, o.props);
    for (let j = 0; j < Math.min(n.children.length, o.children.length); j++) {
      updateElement(p.childNodes[i], n.children[j], o.children[j], j);
    }
  }
}

function h(type, props, ...children) {
  return { type, props: props || {}, children };
}