<!--// Copyright 1996 - Tomer and Yehuda Shiran
// This example will appear in our forthcoming book on JavaScript.
// Feel free to "steal" this code provided that you leave this notice as is.
// Additional examples from the book can be found at
// http://www.geocities.com/SiliconValley/9000/
// For more information contact Tomer or Yehuda Shiran <yshiran@iil.intel.com>

// set speed of banner (pause in milliseconds between addition of new character)
var speed = 5 

// decrease value to increase speed (must be positive)
// set pause between completion of message and beginning of following message
var pause = 5000

// increase value to increase pause
// set initial values
var timerID = null
var bannerRunning = false

// create array
var ar = new Array()

// assign the strings to the array's elements
ar[0] = "nog meer Groninger verhalen en gedichten lezen ?"
ar[1] = "voor 15 euro krijgt u een heel jaar lang tijdschrift Krödde thuis bezorgd"
ar[2] = "stuur snel een email naar info@krodde.nl"

// assign index of current message
var message = 0

// empty string initialization
var state = ""

// no value is currently being displayed
clearState()

// stop the banner if it is currently running
function stopBanner() {
   // if banner is currently running
   if (bannerRunning)
   // stop the banner
   clearTimeout(timerID)
   // timer is now stopped
   timerRunning = false
}

// start the banner
function startBanner() {
   // make sure the banner is stopped
   stopBanner()
   // start the banner from the current position
   showBanner()
}

// assign state a string of "0" characters of the length of the current message
function clearState() {
   // initialize to empty string
   state = ""
   // create string of same length containing 0 digits
   for (var i = 0; i < ar[message].length; ++i) {	
      state += "0"
   }
}

// display the current message
function showBanner() {
   // if the current message is done
   if (getString()) {
      // increment message
      message++
      // if new message is out of range wrap around to first message
   if (ar.length <= message)
      message = 0
      // new message is first displayed as empty string
      clearState()
      // display next character after pause milliseconds
      timerID = setTimeout("showBanner()", pause)
   }
   else {
      // initialize to empty string
      var str = ""
      // built string to be displayed
      // (only character selected thus far are displayed)
      for (var j = 0; j < state.length; ++j) {
         str += (state.charAt(j) == "1") ? ar[message].charAt(j) : "     "
      }
      // partial string is placed in status bar
      window.status = str
      // add another character after speed milliseconds
      timerID = setTimeout("showBanner()", speed)
   }
}

function getString() {
   // set variable to true (it will stay true unless proven otherwise)
   var full = true
   // set variable to false if a free space is found in string
   // (a not-displayed char)
   for (var j = 0; j < state.length; ++j) {
      // if character at index j of current message has not been placed
      // in displayed string
      if (state.charAt(j) == 0)
         full = false
   }
   // return true immediately if no space found (avoid infinitive loop later)
   if (full) return true
   // search for random until free space found (braoken up via break statement)
   while (1) {
      // a random number (between 0 and state.length - 1 == message.length - 1)
      var num = getRandom(ar[message].length)
      // if free space found break infinitive loop
      if (state.charAt(num) == "0")
         break
   }
   // replace the 0 character with 1 character at place found
   state = state.substring(0, num) + "1" + state.substring(num + 1, state.length)
   // return false because the string was not full (free space was found)
   return false
}

function getRandom(max) {
   // create instance of current date
   var now = new Date()
   // create a random number (good generator)
   var num = now.getTime() * now.getSeconds() * Math.random()
   // cut random number to value between 0 and max - 1, inclusive
   return num % max
}

startBanner()
// -->