function retrieveCookie() {
  if (document.cookie !== "") {
    if (document.cookie.indexOf("Prescription=") != -1) {
      var contents = document.cookie
      contents = contents.substring((contents.indexOf("Prescription=") + 13), contents.length)
      var items = contents.split(":")
      with (document) {
        getElementById('patient_number').value = unescape(items[1])
        getElementById('date_of_birth').value = unescape(items[2])
        getElementById('contact_telephone').value = unescape(items[3])
        getElementById('chemist_involved').selectedIndex = unescape(items[4])
        for (var i=1; i<=8; i++) {
          getElementById('medication'+i).value = unescape(items[3*i + 2])
          getElementById('strength'+i).value = unescape(items[3*i + 3])
        }
        getElementById('comment').value = unescape(items[29])
        getElementById('save').checked = true
      }
    }
  }
}

function storeCookie() {
  var contents = ""
  var expiryDate = new Date()
  var expiryYear = expiryDate.getYear()
  with (document) {
    contents = contents + ":" + escape(getElementById('patient_number').value)
    contents = contents + ":" + escape(getElementById('date_of_birth').value)
    contents = contents + ":" + escape(getElementById('contact_telephone').value)
    contents = contents + ":" + escape(getElementById('chemist_involved').selectedIndex)
    for (var i=1; i<=8; i++) {
      contents = contents + ":" + escape(getElementById('medication'+i).value)
      contents = contents + ":" + escape(getElementById('strength'+i).value)
      contents = contents + ":" + escape(getElementById('amount'+i).value)
    }
    contents = contents + ":" + escape(getElementById('comment').value)
  }
  if (expiryYear<1000) {expiryYear = 1900 + expiryYear}
  expiryDate.setYear(expiryYear + 1)
  document.cookie = "Prescription=" + contents + "; expires=" + expiryDate.toGMTString() + "; path=/"
}


function deleteCookie() {
  var contents = ""
  var expiryDate = new Date()
  document.cookie = "Prescription=" + contents + "; expires=" + expiryDate.toGMTString() + "; path=/"
}