function check_form() {

  var error_message = unescape("<?php echo xtc_js_lang(JS_ERROR); ?>");

  var error_found = false;

  var error_field;

  var keywords = document.getElementById("advanced_search").keywords.value;

  var pfrom = document.getElementById("advanced_search").pfrom.value;

  var pto = document.getElementById("advanced_search").pto.value;

  var pfrom_float;

  var pto_float;



  if ( (keywords == '' || keywords.length < 1) && (pfrom == '' || pfrom.length < 1) && (pto == '' || pto.length < 1) ) {

    error_message = error_message + unescape("<?php echo xtc_js_lang(JS_AT_LEAST_ONE_INPUT); ?>");

    error_field = document.getElementById("advanced_search").keywords;

    error_found = true;

  }



  if (pfrom.length > 0) {

    pfrom_float = parseFloat(pfrom);

    if (isNaN(pfrom_float)) {

      error_message = error_message + unescape("<?php echo xtc_js_lang(JS_PRICE_FROM_MUST_BE_NUM); ?>");

      error_field = document.getElementById("advanced_search").pfrom;

      error_found = true;

    }

  } else {

    pfrom_float = 0;

  }



  if (pto.length > 0) {

    pto_float = parseFloat(pto);

    if (isNaN(pto_float)) {

      error_message = error_message + unescape("<?php echo xtc_js_lang(JS_PRICE_TO_MUST_BE_NUM); ?>");

      error_field = document.getElementById("advanced_search").pto;

      error_found = true;

    }

  } else {

    pto_float = 0;

  }



  if ( (pfrom.length > 0) && (pto.length > 0) ) {

    if ( (!isNaN(pfrom_float)) && (!isNaN(pto_float)) && (pto_float < pfrom_float) ) {

      error_message = error_message + unescape("<?php echo xtc_js_lang(JS_PRICE_TO_LESS_THAN_PRICE_FROM); ?>");

      error_field = document.getElementById("advanced_search").pto;

      error_found = true;

    }

  }



  if (error_found == true) {

    alert(error_message);

    error_field.focus();

    return false;

  }

}



function popupWindow(url) {

  window.open(url,'popupWindow','toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=yes,resizable=yes,copyhistory=no,width=450,height=280,screenX=150,screenY=150,top=150,left=150')

}