// JavaScript Document
function checkform()
{
var chkname, chkemail, chkproduct_number, chkcolor, chksize;
   with(window.document.enquiry_form)
   {
	  chkname = name;
	  chkemail = email;
	  chkproduct_number = product_number;
	  chkcolor = product_color;
	  chksize = product_size; 
   }
   if (!document.enquiry_form.enquiry[0].checked && !document.enquiry_form.enquiry[1].checked) 
   {
	// no radio button is selected
	alert('Please select enquire option.');
	return false;
   }
   else if(trim(chkname.value) == '')
   {
      alert('Please enter your name.');
      chkname.focus();
      return false;
   }
   else if(trim(chkemail.value) == '')
   {
      alert('Please enter your email address.');
      chkemail.focus();
      return false;
   }
   else if(!isEmail(trim(chkemail.value)))
   {
      alert('Email address is invalid.');
      chkemail.focus();
      return false;
   }
   else if(trim(chkproduct_number.value) == '')
   {
      alert('Product number is required!');
      chkproduct_number.focus();
      return false;
   }
   else if(!isProductNumber(trim(chkproduct_number.value)))
   {
      alert('oops..invalid product number!');
      chkproduct_number.focus();
      return false;
   }
   else if(trim(chkcolor.value) == '')
   {
      alert('What colour would you like??');
      chkcolor.focus();
      return false;
   }
   else if(trim(chksize.value) == '')
   {
      alert('Please enter the size.');
      chksize.focus();
      return false;
   }
   else if (!document.enquiry_form.terms.checked) 
   {
	// no radio button is selected
	alert('You must agree to the terms & conditions.');
	return false;
   }
   else
   {
	  chkname.value = trim(chkname.value);
	  chkemail.value = trim(chkemail.value); 
	  chkproduct_number.value = trim(chkproduct_number.value);
	  chkcolor.value = trim(chkcolor.value);
	  chksize.value = trim(chksize.value);
      return true;
   }
}

function trim(str)
{
   return str.replace(/^\s+|\s+$/g,'');
}

function isEmail(str)
{
	var regex = /^[-_.a-z0-9]+@(([-_a-z0-9]+\.)+(ad|ae|aero|af|ag|ai|al|am|an|ao|aq|ar|arpa|as|at|au|aw|az|ba|bb|bd|be|bf|bg|bh|bi|biz|bj|bm|bn|bo|br|bs|bt|bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|com|coop|cr|cs|cu|cv|cx|cy|cz|de|dj|dk|dm|do|dz|ec|edu|ee|eg|eh|er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gh|gi|gl|gm|gn|gov|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie|il|in|info|int|io|iq|ir|is|it|jm|jo|jp|ke|kg|kh|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly|ma|mc|md|mg|mh|mil|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|museum|mv|mw|mx|my|mz|na|name|nc|ne|net|nf|ng|ni|nl|no|np|nr|nt|nu|nz|om|org|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|pro|ps|pt|pw|py|qa|re|ro|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sj|sk|sl|sm|sn|so|sr|st|su|sv|sy|sz|tc|td|tf|tg|th|tj|tk|tm|tn|to|tp|tr|tt|tv|tw|tz|ua|ug|uk|um|us|uy|uz|va|vc|ve|vg|vi|vn|vu|wf|ws|ye|yt|yu|za|zm|zw)|(([0-9][0-9]?|[0-1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5])\.){3}([0-9][0-9]?|[0-1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5]))$/i;
	return regex.test(str);
}

function isProductNumber(str)
{
	var regex = /^[A-Za-z]{2}[0-9]{5}$/;
	return regex.test(str);
}