function addClass(element, cls) {
  removeClass(element, 'errorClass');
  removeClass(element, 'okClass');
  if(element && element.className.indexOf(cls) == -1) {
    element.className = element.className + ' ' + cls;
  }
}
function removeClass(element, cls) {
  if(element) {
    element.className = element.className.replace(cls, '');
  }
}



function pridatKomentar(responseText) {
  document.getElementById( globAjax.element ).innerHTML = responseText;
}






function knihaNavstevCheckNick() {
  var elm = document.getElementById('knihaNavstevNick');
  var elmComment = document.getElementById('knihaNavstevNickComment');
  if( isEmpty(elm.value) ) {
    addClass(elm, 'errorClass');
    elmComment.innerHTML = " Povinná položka!";
    return false;
  } else {
    addClass(elm, 'okClass');
    elmComment.innerHTML = "";
    return true;
  }
}

function knihaNavstevCheckEmail() {
  var elm = document.getElementById('knihaNavstevEmail');
  var elmComment = document.getElementById('knihaNavstevEmailComment');
  if( isEmpty(elm.value)==false ) {
    if( !isEmail(elm.value) ) {
      addClass(elm, 'errorClass');
      elmComment.innerHTML = " Špatný formát e-mailu!";
      return false;
    } else {
      addClass(elm, 'okClass');
      elmComment.innerHTML = "";
    }
  }
  return true;
}

function knihaNavstevCheckWeb() {
  var elm = document.getElementById('knihaNavstevWeb');
  var elmComment = document.getElementById('knihaNavstevWebComment');

//  elm.value = elm.value.replace("http://", "");

  if( isEmpty(elm.value)==false ) {
    if( !isWebLink(elm.value) ) {
      addClass(elm, 'errorClass');
      elmComment.innerHTML = " Špatný formát webové adresy!";
      return false;
    } else {
      elmComment.innerHTML = "";
      addClass(elm, 'okClass');
    }
  }
  return true;
}

function knihaNavstevCheckText() {
  var elm = document.getElementById('knihaNavstevText');
  var elmComment = document.getElementById('knihaNavstevTextComment');
  if( isEmpty(elm.value) ) {
    addClass(elm, 'errorClass');
    elmComment.innerHTML = " Povinná položka!";
    return false;
  } else {
    addClass(elm, 'okClass');
    elmComment.innerHTML = "";
    return true;
  }

}





function createFormEntry(text, elmName, formElm) {
  var li = document.createElement('li');
  var label = document.createElement('label');
  var br = document.createElement('br');

  label.innerHTML = text;

  li.appendChild(label);
  li.appendChild(br);

  switch(formElm) {
    case 'input': li.appendChild( createDomInput(elmName) ); break
    case 'textarea': li.appendChild( createDomTextarea(elmName) ); break
  }

  return li;
}




function createDomInput(elmName) {
  var input = document.createElement('input');
  input.setAttribute('id', elmName);
  input.setAttribute('type', 'text');
  input.setAttribute('name', elmName);

  switch(elmName) {
    case 'knihaNavstevNick':
      input.setAttribute('onblur', 'return knihaNavstevCheckNick();');
      input.setAttribute('tabindex', '1');
      break;
    case 'knihaNavstevEmail':
      input.setAttribute('onblur', 'knihaNavstevCheckEmail();');
      break;
    case 'knihaNavstevWeb':
      input.setAttribute('onblur', 'knihaNavstevCheckWeb();');
      break;
  }

  return input;
}




function createDomTextarea(elmName) {
  var input = document.createElement('textarea');
  input.setAttribute('id', elmName);
  input.setAttribute('name', elmName);

  input.setAttribute('onblur', 'return knihaNavstevCheckText();');
  input.setAttribute('tabindex', '2');

  return input;
}




function createDomSubmit(elmName) {
  var input = document.createElement('input');
  input.setAttribute('id', elmName);
  input.setAttribute('type', 'submit');
  input.setAttribute('name', elmName);

  return input;
}




function pridatKomentar_handler() {
  try {
    var bodyElm = document.getElementsByTagName('body');
    var div = document.createElement('div');
    div.setAttribute('id','divKomentare');


    var form = document.createElement('form');
    form.setAttribute('id','formKomentare');
    form.setAttribute('action','');
    form.setAttribute('method','post');
    form.setAttribute('onsubmit','return checkFormKomentare();');

    var h2 = document.createElement('h2');
    h2.innerHTML = "Přidat komentář";
    var br = document.createElement('br');

    bodyElm[0].appendChild(div)
    div.appendChild(form);
    form.appendChild(h2);

    var ul = document.createElement('ul');
    var li1 = createFormEntry('Nick', 'knihaNavstevNick', 'input');
    ul.appendChild( li1 );

    var li2 = createFormEntry('E-mail', 'knihaNavstevEmail', 'input');
    ul.appendChild( li2 );
    var li21 = createFormEntry('Web', 'knihaNavstevWeb', 'input');
    ul.appendChild( li21 );

    var li3 = createFormEntry('Text', 'knihaNavstevText', 'textarea');
    ul.appendChild( li3 );

    var li4 = document.createElement('li');
    var span = document.createElement('span');
    span.innerHTML = "  ";
    var span2 = document.createElement('span');
    span2.innerHTML = "  ";

    var submit2 = createDomSubmit('_next2');
    submit2.setAttribute('tabindex', '3');
    submit2.setAttribute('value', 'Náhled');
    li4.appendChild(submit2);
    li4.appendChild(span);

    var submit = createDomSubmit('_next');
    submit.setAttribute('tabindex', '4');
    submit.setAttribute('value', 'Uložit');
    li4.appendChild(submit);

    li4.appendChild(span2);

    var button = document.createElement('button');
    button.innerHTML = "Zrušit";
    button.setAttribute('tabindex', '5');
    var aClose = document.createElement('a');
    aClose.setAttribute('href','#');
    aClose.setAttribute('id','pridatKomentarZavrit');
    aClose.setAttribute('onclick','return pridatKomentarZavrit();');
    aClose.appendChild( button );
    li4.appendChild(aClose);

    ul.appendChild( li4 );


    form.appendChild(ul);

    return true;
  }catch(err) {
//    if( debug ) window.alert("Chyba: " + err.message);
    window.alert("Chyba: " + err.message);
    return false;
  }
  return false;
}




function pridatKomentarZavrit() {
  try {
    var bodyElm = document.getElementsByTagName('body'); // ziskani elementu body
    var div = document.getElementById('divKomentare');
    bodyElm[0].removeChild(div);
  }catch(err) {
    if( debug ) window.alert("Chyba: " + err.message);
    return false;
  }
  return false;
}




function checkFormKomentare() {
  var elmNick = document.getElementById('knihaNavstevNick');
  var elmText = document.getElementById('knihaNavstevText');
  var elmEmail = document.getElementById('knihaNavstevEmail');
  var elmWeb = document.getElementById('knihaNavstevweb');

  var retvalNick = knihaNavstevCheckNick();
  var retvalText = knihaNavstevCheckText();
  var retvalEmail = knihaNavstevCheckEmail();
  var retvalWeb = knihaNavstevCheckWeb();

  if(retvalNick && retvalText && retvalEmail && retvalWeb) {
    return true;
  }

  return false;
}