/* Javascript Functions to Validate String, Number, Email and String with specified Characters */

var whitespace = " \t\n\r";

function isEmpty(s)  //Checks whether string is Empty
	{  
		return ((s == null) || (s.length == 0))
	}

function isWhitespace (s) //Checks for White spaces in the string 
	{  
		var i;
	 	if (isEmpty(s)) return true;
	 	   for (i = 0; i < s.length; i++)
	 	   {   
	 	       var c = s.charAt(i);
	 	       if (whitespace.indexOf(c) == -1) return false;
	 	   }
		   return true;
	}

function noWhitespace (s) //no white space in between the string
	{  
		var i;
	 	if (isEmpty(s)) return true;
	 	   for (i = 0; i < s.length; i++)
	 	   {   
	 	       var c = s.charAt(i);
				if (whitespace.indexOf(c) == 0){
			   	   return true;
				}
	 	   }
		   return false;
	}

function isNumber (s) //Checks whether the number is numeric
	{  
	    var i;
		var bag="1234567890"
	    for (i = 0; i < s.length; i++)
	    {   
	        var c = s.charAt(i);
	        if (bag.indexOf(c) == -1) return false;
	    }
	    return true;
	}

function isCharsInBag (s, bag) /* Checks whether the string only contains the characters 
								specified in the parameter bag */
	{  
	    var i;
	    for (i = 0; i < s.length; i++)
	    {   
	        var c = s.charAt(i);
	        if (bag.indexOf(c) == -1) return false;
	    }
	    return true;
	}
	
function isString (s) //Checks whether the string contains only alphabets, . and _
	{  
	    var i;
		var bag="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz _."
	    for (i = 0; i < s.length; i++)
	    {   
	        var c = s.charAt(i);
	        if (bag.indexOf(c) == -1) return false;
	    }
	    return true;
	}
	
	function isCaseSensitive (s) //Checks whether the string contains only alphabets, . and _
	{  
	    var i;
		var bag="abcdefghijklmnopqrstuvwxyz _"
	    for (i = 0; i < s.length; i++)
	    {   
	        var c = s.charAt(i);
	        if (bag.indexOf(c) == -1) return false;
	    }
	    return true;
	}
	
	
function isAlpha (s) //Checks whether the string contains only alphabets
	{  
	    var i;
		var bag="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz "
	    for (i = 0; i < s.length; i++)
	    {   
	        var c = s.charAt(i);
	        if (bag.indexOf(c) == -1) return false;
	    }
	    return true;
	}
function isAlphaNumeric (s) //Checks whether the string contains only alphabets and Numbers
	{  
	    var i;
		var bag="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_0123456789-/ ";
	    for (i = 0; i < s.length; i++)
	    {   var c = s.charAt(i);
			if (bag.indexOf(c) == -1) return false;
		}
		return true;
	}
	
function isTextNumeric (s) //Checks whether the string contains only alphabets and Numbers
	{  
	    var i;
		var bag="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
	    for (i = 0; i < s.length; i++)
	    {   var c = s.charAt(i);
			if (bag.indexOf(c) == -1) return false;
		}
		return true;
	}
		
function isEmail (emailStr) //Checks whether the given string is a valid EMail address
 	{
		var emailPat=/^(.+)@(.+)$/
		var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
		var validChars="\[^\\s" + specialChars + "\]"
		var quotedUser="(\"[^\"]*\")"
		var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
		var atom=validChars + '+'
		var word="(" + atom + "|" + quotedUser + ")"
		var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
		var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")

		var matchArray=emailStr.match(emailPat)

		if (matchArray==null) 
		{
			return false
		}
		
		var user=matchArray[1]
		var domain=matchArray[2]
		
		
		if (user.match(userPat)==null) 
		{
		    return false
		}
		
		var IPArray=domain.match(ipDomainPat)
		
		if (IPArray!=null) 
		{
		  	for (var i=1;i<=4;i++) 
		  		{
			    if (IPArray[i]>255) 
					{
			    		return false
			    	}
		    	}
		    return true
		}
	
		var domainArray=domain.match(domainPat)
		
		if (domainArray==null) 
			{
		    	return false
			}
		
		var atomPat=new RegExp(atom,"g")
		var domArr=domain.match(atomPat)
		var len=domArr.length

		if (domArr[domArr.length-1].length<2 || 
		    domArr[domArr.length-1].length>3) 
			{
			   return false
			}
		
		if (len<2) 
			{
			   var errStr="This address is missing a hostname!"
	   		   return false
			}

		return true;
	}