/*
(C)2006 Michael Katschner
mkcrypt - "Verschlüsselungsprogramm" zum Verstecken der Emailadresse vor Adress-Harvestern...
*/

function mkcrpt(v,r)
{
	offset=1;
	cString='';
	for (i=0;i < v.length; i++)
	{
		cString += shift(v.substr(i,1),offset * ((r==0)?1:-1));
		offset ++;
		if (offset > 9)
		{
			offset = 1; 
		}
	}
	return cString;
}


function shift(chr,amt)
{
	var lb=new Array(3);
	var ub=new Array(3);
	if (chr == '.')
	{
		return '$';
	}
	if (chr == '$')
	{
		return '.';
	}
	if (chr == '~')
	{
		return String.fromCharCode(64);
	}
	if (chr == ':')
	{
		return '[';
	}
	if (chr == '[')
	{
		return ':';
	}
	if (chr == '-')
	{
		return ']';
	}
	if (chr == ']')
	{
		return '-';
	}
	
	lb[0]=48;ub[0]=57;lb[1]=65;ub[1]=90;lb[2]=97;ub[2]=122;
	val=chr.charCodeAt(0);
	if (val == '64')
	{
		return '~';
	}
	bereich = 0;
	if (val > 57 && val < 97)
	{
		bereich = 1;
	}
	else
	{
		if (val > 96)
		{
			bereich = 2;
		}	
	}
	if (amt > 0)
	{
		if ((val + amt) > ub[bereich])
		{
			nval=val + amt + ((bereich > 0)?-26:-10); 	
		}
		else
		{
			nval=val + amt;
		}
	}
	else
	{
		if ((val + amt) < lb[bereich])
		{
			nval=val + amt + ((bereich > 0)?26:10); 	
		}
		else
		{
			nval=val + amt;
		}
	}	
	return String.fromCharCode(nval);
}

function emailcheck(s)
{
 if (s == "")
 {
 	return true;
 }
 var a = false;
 var res = false;
 if(typeof(RegExp) == 'function')
 {
  var b = new RegExp('abc');
  if(b.test('abc') == true){a = true;}
  }

 if(a == true)
 {
  reg = new RegExp('^([a-zA-Z0-9\\-\\.\\_]+)'+
                   '(\\@)([a-zA-Z0-9\\-\\.]+)'+
                   '(\\.)([a-zA-Z]{2,4})$');
  res = (reg.test(s));
 }
 else
 {
  res = (s.search('@') >= 1 &&
         s.lastIndexOf('.') > s.search('@') &&
         s.lastIndexOf('.') >= s.length-5)
 }
 return(res);
}