function insertSmile(code){
  clearField(objGet('textarea'), 'text příspěvku');
  objGet('textarea').value += " " + code + " ";
}

function clearField(obj, str){
  if(obj.value == str) obj.value='';
}

function validateComment(obj){
  if(obj.captcha.value == ''
     || obj.captcha.value == 'opište číslo z obrázku' 
     || obj.author.value == '' 
     || obj.cont.value == '' 
     || obj.cont.value == 'text příspěvku' 
     || (obj.email.value != '' && wrong_mail_address(obj.email.value))
     ){
    obj.submit_comment.disabled=true;
  }
  else{
    obj.submit_comment.disabled=false;
  }
}

function fit_window(){
  pictureWidth = objGet('pic').width;
  pictureHeight = objGet('pic').height;
  window.resizeTo(pictureWidth+60, pictureHeight+96);  
}

function wrong_mail_address(adresa){
  var re = /^[_a-zA-Z0-9\.\-]+@[_a-zA-Z0-9\.\-]+\.[a-zA-Z]{2,4}$/;
  return re.test(adresa) == 0;
}

function objGet(id){
   if(Boolean(document.getElementById))
      return document.getElementById(id);
   else if(Boolean(document.all))
      return eval('document.all.'+id);
   else
      return eval('document.'+id);
}

function switchImg(url){
  objGet('main-pic').src=url;
}

function clearPassword(){
  x=objGet('login_form');
  if(x.password.value=='Vložte heslo...') x.password.value='';
}

function clearEmail(){
  x=objGet('login_form');
  if(x.login.value=='Vložte e-mail...') x.login.value='';
}

function clearNewsletter(){
  x=objGet('newsletter-box');
  if(x.value=='Vložte Váš e-mail...') x.value='';
}

function clearkeywords(){
  x=objGet('search');
  if(x.keywords.value=='Zadejte klíčová slova...') x.keywords.value='';
}

function validateReg(edit){
  form=objGet('reg_form');
 
    if(form.name.value=="" || form.surname.value==""
       || form.address.value=="" || form.city.value==""
       || form.post_code.value==""  || form.phone.value==""
       || wrong_mail_address(form.email.value) || (form.password.value=="" && !edit)) 
      objGet('submit').disabled=true;
      
    else objGet('submit').disabled=false;
}