// Declaring required variables
var digits = "0123456789";
// non-digit characters which are allowed in phone numbers
var phoneNumberDelimiters = "()- ";
// characters which are allowed in international phone numbers
// (a leading + is OK)
var validWorldPhoneChars = phoneNumberDelimiters + "+";
// Minimum no of digits in an international phone no.
var minDigitsInIPhoneNumber = 10;


function echeck(str) {

	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	if (str.indexOf(at)==-1){
	   alert("Invalid E-mail ID")
	   return false
	}

	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
	   alert("Invalid E-mail ID")
	   return false
	}

	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		alert("Invalid E-mail ID")
		return false
	}

	 if (str.indexOf(at,(lat+1))!=-1){
		alert("Invalid E-mail ID")
		return false
	 }

	 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		alert("Invalid E-mail ID")
		return false
	 }

	 if (str.indexOf(dot,(lat+2))==-1){
		alert("Invalid E-mail ID")
		return false
	 }
	
	 if (str.indexOf(" ")!=-1){
		alert("Invalid E-mail ID")
		return false
	 }

	 return true					
}

function isInteger(s)
{   
	var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function trim(s)
{   var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not a whitespace, append to returnString.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (c != " ") returnString += c;
    }
    return returnString;
}

function stripCharsInBag(s, bag)
{   var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function checkInternationalPhone(strPhone){
	var bracket=3
	strPhone=trim(strPhone)
	if(strPhone.indexOf("+")>1) return false
	if(strPhone.indexOf("-")!=-1)bracket=bracket+1
	if(strPhone.indexOf("(")!=-1 && strPhone.indexOf("(")>bracket)return false
	var brchr=strPhone.indexOf("(")
	if(strPhone.indexOf("(")!=-1 && strPhone.charAt(brchr+2)!=")")return false
	if(strPhone.indexOf("(")==-1 && strPhone.indexOf(")")!=-1)return false
	s=stripCharsInBag(strPhone,validWorldPhoneChars);
	return (isInteger(s) && s.length >= minDigitsInIPhoneNumber);
}

function isValidURL(url){
    var RegExp = /^(([\w]+:)?\/\/)?(([\d\w]|%[a-fA-f\d]{2,2})+(:([\d\w]|%[a-fA-f\d]{2,2})+)?@)?([\d\w][-\d\w]{0,253}[\d\w]\.)+[\w]{2,4}(:[\d]+)?(\/([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)*(\?(&?([-+_~.\d\w]|%[a-fA-f\d]{2,2})=?)*)?(#([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)?$/;
    if(RegExp.test(url)){
        return true;
    }else{
        return false;
    }
}