plugin: jquery form validation

gistfile1.txt

markup
------
<div class="scan-form"> 
      <h1> <span>Start</span> your free scan now!</h1>
      <form id="sacnForm" action="javascript:alert('success!');">
          <input type="text" name="scanBar" id="scanBar" placeholder="Your website URL" value="" />
        <input type="submit" value="start">
      </form>
    
    <div class="alerts">
        <small></small>
        <p></p>
    </div> 
    
</div>


jQuery
------
function validateURL(textval) {
  var urlregex = new RegExp(
        "^(http:\/\/www.|https:\/\/www.|ftp:\/\/www.|www.){1}([0-9A-Za-z]+\.)");
  return urlregex.test(textval);
}

 $("#sacnForm").submit(function() {
      if (validateURL($("#scanBar").val())) {
         $("#scanBar").removeClass("error"); 
        return true;
      }
     
     if ($("#scanBar").val().length >= 40) {
     $(".alerts p").text("URL has to be less than 40 characters").show(); 
     }
     
     
      if ($("#scanBar").val() == "") {
        $("#scanBar").attr("placeholder","Put your URL here to start scan!"); 
        $("#scanBar").css('border','3px solid #ffbf32');
        return false;
      }
     
      $("#scanBar").keyup(function(){
      $(".alerts").slideUp();
      $("#scanBar").removeClass("error");     
      });
     
     $("#scanBar").click(function(){
      $("#scanBar").select();
      });
     

     
     $("#scanBar").addClass("error");
     $(".alerts p").text($("#scanBar").val() + 'Not valid!').show();
     $(".alerts").fadeIn();
      return true;
    });​