function b64arrays()
{
  var b64s='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
  b64 = [];f64 =[];
  for (var i=0; i<b64s.length ;i++)
  {
    b64[i] = b64s.charAt(i);
    f64[b64s.charAt(i)] = i;
  }
}

function b64t2d(t)
{
  var d=[]; var i=0;
  // zur decodierung die Umbrueche killen
  t=t.replace(/\n|\r/g,""); t=t.replace(/=/g,"");
  while (i<t.length)
  {
    d[d.length] = (f64[t.charAt(i)]<<2) | (f64[t.charAt(i+1)]>>4);
    d[d.length] = (((f64[t.charAt(i+1)]&15)<<4) | (f64[t.charAt(i+2)]>>2));
    d[d.length] = (((f64[t.charAt(i+2)]&3)<<6) | (f64[t.charAt(i+3)]));
    i+=4;
  }
  if (t.length%4 == 2)
    d = d.slice(0, d.length-2);
  if (t.length%4 == 3)
    d = d.slice(0, d.length-1);
  return d;
}

function writemail(address)
{
  charcodes = b64t2d(address);
  address = "";
  for(i=0; i< charcodes.length; i++)
    address += String.fromCharCode(charcodes[i]);

  document.write("<a href=\"mailto:"+address+"\"><img src=\"img/mail.gif\" alt=\"Email\" border=0></a>");
}

b64arrays();

function insert(aTag, eTag) {
  var input = document.forms['horst'].elements['text'];
  input.focus();
  /* für Internet Explorer */
  if(typeof document.selection != 'undefined')
  {
    /* Einfügen des Formatierungscodes */
    var range = document.selection.createRange();
    var insText = range.text;
    range.text = aTag + insText + eTag;
    /* Anpassen der Cursorposition */
    range = document.selection.createRange();
    if (insText.length == 0) {
      range.move('character', -eTag.length);
    } else {
      range.moveStart('character', aTag.length + insText.length + eTag.length);
    }
    range.select();
  }
  /* für neuere auf Gecko basierende Browser */
  else if(typeof input.selectionStart != 'undefined')
  {
    /* Einfügen des Formatierungscodes */
    var start = input.selectionStart;
    var end = input.selectionEnd;
    var insText = input.value.substring(start, end);
    input.value = input.value.substr(0, start) + aTag + insText + eTag + input.value.substr(end);
    /* Anpassen der Cursorposition */
    var pos;
    if (insText.length == 0) {
      pos = start + aTag.length;
    } else {
      pos = start + aTag.length + insText.length + eTag.length;
    }
    input.selectionStart = pos;
    input.selectionEnd = pos;
  }
  /* für die übrigen Browser */
  else
  {
    /* Abfrage der Einfügeposition */
    var pos;
    var re = new RegExp('^[0-9]{0,3}$');
    while(!re.test(pos)) {
      pos = prompt("Einfügen an Position (0.." + input.value.length + "):", "0");
    }
    if(pos > input.value.length) {
      pos = input.value.length;
    }
    /* Einfügen des Formatierungscodes */
    var insText = prompt("Bitte geben Sie den zu formatierenden Text ein:");
    input.value = input.value.substr(0, pos) + aTag + insText + eTag + input.value.substr(pos);
  }
}