var discnt = 0;   // no default percent discount

var coupons = new Array (  // place to put coupon codes
  "coup1",                 // 1st coupon value - comma seperated
  "coup2",                 // 2nd coupon value - add all you want
  "bowl05"                  // 3rd coupon value
);
var coupdc  = new Array (  // place to put discounts for coupon vals
  5,
  10,
  15
);
var coupval = "(blanket)"; // what user entered as coupon code

function ChkCoup () {      // check user coupon entry
var i;
  discnt = 0;              // assume the worst
  for (i=0; i<coupons.length; i++) {
    if (coupval == coupons[i]) {
      discnt = coupdc[i];  // remember the discount amt
      alert ("Valid coupon number! \n\n" + discnt + 
             "% discount now in effect.");
      return;
    }
  }
  alert ("'" + coupval + "'  is not a valid code!");
}

function Dollar (val) {      // force to valid dollar amount
var str,pos,rnd=0;
  if (val < .995) rnd = 1;  // for old Netscape browsers
  str = escape (val*1.0 + 0.005001 + rnd);  // float, round, escape
  pos = str.indexOf (".");
  if (pos > 0) str = str.substring (rnd, pos + 3);
  return str;
}

function ReadForm (obj1) {  // apply the discount
var amt,des;
  amt = obj1.baseamt.value*1.0;       // base amount
  des = obj1.basedes.value;           // base description

  if (discnt > 0) {                   // only if discount is active
    amt = Dollar (amt - (amt * discnt/100.0));
    des = des + ", " + discnt + "% dis, COUP = " + coupval;
  }

  obj1.amount.value = Dollar (amt);
  obj1.item_name.value = des;
}