//  function to trim a string
function trim(str_key){
	str_key = rtrim(str_key);
	str_key = ltrim(str_key);
	return str_key;
}

// function to right trim a string
function rtrim(str_key){
	while(str_key.charAt(str_key.length-1)==" "){
		str_key=str_key.substr(0,str_key.length-1);
	}	
	return str_key;
}

// function to left trim a string
function ltrim(str_key){
	while(str_key.charAt(0)==" "){
		str_key=str_key.substr(1);
	}	
	return str_key;
}

function compareDate(sdate,edate){
	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/; 
	var matchArray1 = sdate.match(datePat); 
	smonth = matchArray1[1]; // parse date into variables 
	sday = matchArray1[3]; 
	syear = matchArray1[4]; 
	var matchArray2 = edate.match(datePat); 
	emonth = matchArray2[1]; // parse date into variables 
	eday = matchArray2[3]; 
	eyear = matchArray2[4]; 
	if( eyear>syear) return true;
	else if(eyear == syear){
	if(emonth > smonth) return true;
	else if(emonth == smonth){
	if(eday > sday) return true;
		else return false;
	}
		else  return false;
	}
	else return false;
}
// End camparedate -------------------------------------> 
function compareTaskDate(sdate,edate){
	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/; 
	var matchArray1 = sdate.match(datePat); 
	smonth = matchArray1[1]; // parse date into variables 
	sday = matchArray1[3]; 
	syear = matchArray1[4]; 
	var matchArray2 = edate.match(datePat); 
	emonth = matchArray2[1]; // parse date into variables 
	eday = matchArray2[3]; 
	eyear = matchArray2[4]; 
	if( eyear>syear) return true;
	else if(eyear == syear){
		if(emonth > smonth) return true;
		else if(emonth == smonth){
			if(eday > sday) return true;
			else if(eday ==sday) return true;
			else return false;
		}
		else  return false;
	}
	else return false;
}
// End camparetaskdate -------------------------------------> 


// function to check an year YYYY-MM-DD
function checkYear(strYear){	
	var dateStr = new String(strYear);
	dateStr = ltrim(dateStr);
	dateStr = rtrim(dateStr);
	
	//var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/; 
	var datePat = /^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9].*$/; 
	days = new Array(0,31,28,31,30,31,30,31,31,30,31,30,31);
	
	var matchArray = dateStr.match(datePat); // is the format ok? 
	if (matchArray == null){
		alert("Enter date in YYYY-MM-DD format. eg 2003-01-21");
		return false;
	}
	else{
		var temp_year = 0;
		var temp_month = 0;
		var i = parseInt(dateStr.substr(0, 4));
		temp_year = i;
		if(i < 2000){
			alert("Please enter an year greater than 2000");
			return false;
		}
		
		i = parseInt(dateStr.substr(5, 2))
		if(dateStr.substr(5, 1) == "0"){
			i = parseInt(dateStr.substr(6, 1))
		}
		if(i < 1 || i > 12){
			alert("Please enter a valid month");
			return false;
		}
		temp_month = i;
		var d =days[i];
		
		i = parseInt(dateStr.substr(8))
		if((temp_year % 4 == 0) && (temp_month == 2)){
			if(i < 0 || i > 29){
				alert("Please enter a valid day curresponding to the current year and month.");
				return false;
			}
		}else if(i < 0 || i > d){
			alert("Please enter a valid day curresponding to the current year and month.");
			return false;
		}
	}
	return true; 
}

// function to confirm database setup
function confirm_setup(){
	if(confirm("Tables already exists.\nThis action will drop all tables and data and it CANNOT BE UNDONE. \nAre you sure that you want to run Setup again?")){
		return true;
	}
	return false;
}
// function to open a new window
function openWin(windowURL, windowName, windowFeatures){ 
	window.open(windowURL, windowName, windowFeatures);
	return false; 
}

// function to confirm record deletion
function confirmCleanUp(Link) {
   if (confirm("Are you sure you want to delete ?")) {
      location.href=Link;
   }
}

// to simulate the clicking of the browser back button
function fn_back(){
	window.history.back();
}	

// function to check YEAR with 4 digit
function isYear(snum)
{
	var reInteger = /^[1-9]\d{3}$/
	return reInteger.test(snum)
}
// function to check indiger field
function IsIntegers(snum)
{
	var reInteger = /^\d+$/
    return reInteger.test(snum)
}

// function to check SSN US
function IsSSN(snum)
{
	var reSSN = /^(\d{3})(-)(\d{2})(-)(\d{4})$/	
    return reSSN.test(snum)
}

// function to check US phone - fomat 999-999-9999
function IsPhone(snum)
{
	var rePhone = /^(\d{3})(-)(\d{3})(-)(\d{4})$/	
    return rePhone.test(snum)
}

// Check whether string s is empty.
function isEmpty(s)
{   
	if(trim(s) == ""){
		return true;
	}else{
		return false;
	}
}
// Check whether string s a username.
function IsName( value )
{
    return (/^[a-z]([a-z\s]*)$/i.test(value));
}
// function to check indiger field
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 to check Price value ( with two decimal places )
function isPrice(s)
{  
	s = trim(s);
	var reFloat = /^[\d\.]((\d+(\.\d{0,2})?)|((\d*\.)?\d{0,2}))$/	
	return reFloat.test(s)	   	
}
// function to check float/decimal fileds
function isFloat(s)
{  
	var reFloat = /^((\d+(\.\d*)?)|((\d*\.)?\d+))$/	
	return reFloat.test(s)	   	
}

// function to check username fields
function usernameCheck (s){
  // this is done to avoid any special characters
  var reUsername = /^[a-zA-Z0-9][a-zA-Z0-9_]*$/
  
  if (isEmpty(s)){
  	 alert("Please enter a desired Username. Minimum 8 characters.\nNo spaces, blanks or special characters , except '_'.");
	 return false; 
  } 
  else{
   	 var matchArray = s.match(reUsername); // is the format ok? 
	 if (matchArray == null) { 
		alert("Username should contain only \nalphabets, digits or underscore '_'.\n '_' should not be the first character.");
		return false; 
	 }	 	
	 else{ 
	  	 if(s.length<8){		
			alert("Username should be minimum of 8 characters");	
			return false; 
		 }	
	 }			
  }      	 
  return true;
}

// function to check username fields
function passwordCheck (s){
  // this is done to avoid any special characters
  var rePassword = /^[a-zA-Z0-9][a-zA-Z0-9~!@#$%^&*()]*$/
  
  if (isEmpty(s)){
  	 alert("Please enter a desired Password. Minimum 8 characters.\nNo spaces and blanks allowed.");
	 return false; 
  } 
  else{
   	 var matchArray = s.match(rePassword); // is the format ok? 
	 if (matchArray == null) { 
		alert("Password should contain only alphabets, digits\nor only these special characters ~!@#$%^&*()$\nbut not the first character.");
		return false; 
	 }	 	
	 else{ 
	  	 if(s.length<8){		
			alert("Password should be minimum of 8 characters");	
			return false; 
		 }	
	 }			
  }      	 
  return true;
}
	
// function to validate date field
function isValidDate(dateStr) { 
// Checks for the following valid date formats: 
// MM/DD/YY MM/DD/YYYY MM-DD-YY MM-DD-YYYY 
// Also separates date into month, day, and year variables 

var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/; 

// To require a 4 digit year entry, use this line instead: 
// var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/; 

var matchArray = dateStr.match(datePat); // is the format ok? 
if (matchArray == null) { 
	alert("Date is not in a valid format.") 
	return false; 
} 
month = matchArray[1]; // parse date into variables 
day = matchArray[3]; 
year = matchArray[4]; 
if (month < 1 || month > 12) { // check month range 
alert("Month must be between 1 and 12."); 
return false; 
} 
if (day < 1 || day > 31) {
alert("Day must be between 1 and 31."); 
return false; 
} 
if ((month==4 || month==6 || month==9 || month==11) && day==31) {
alert("Month "+month+" doesn't have 31 days!") 
return false 
} 
if (month == 2) { // check for february 29th 
var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)); 
if (day>29 || (day==29 && !isleap)) { 
alert("February " + year + " doesn't have " + day + " days!"); 
return false; 
} 
} 
return true; // date is valid 
} 
// End date validation -------------------------------------> 

function emailCheck(emailStr) {
	/* The following pattern is used to check if the entered e-mail address
	   fits the user@domain format.  It also is used to separate the username
	   from the domain. */
	var emailPat=/^(.+)@(.+)$/
	/* The following string represents the pattern for matching all special
	   characters.  We don't want to allow special characters in the address. 
	   These characters include ( ) < > @ , ; : \ " . [ ]    */
	var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
	/* The following string represents the range of characters allowed in a 
	   username or domainname.  It really states which chars aren't allowed. */
	var validChars="\[^\\s" + specialChars + "\]"
	/* The following pattern applies if the "user" is a quoted string (in
	   which case, there are no rules about which characters are allowed
	   and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
	   is a legal e-mail address. */
	var quotedUser="(\"[^\"]*\")"
	/* The following pattern applies for domains that are IP addresses,
	   rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
	   e-mail address. NOTE: The square brackets are required. */
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
	/* The following string represents an atom (basically a series of
	   non-special characters.) */
	var atom=validChars + '+'
	/* The following string represents one word in the typical username.
	   For example, in john.doe@somewhere.com, john and doe are words.
	   Basically, a word is either an atom or quoted string. */
	var word="(" + atom + "|" + quotedUser + ")"
	// The following pattern describes the structure of the user
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
	/* The following pattern describes the structure of a normal symbolic
	   domain, as opposed to ipDomainPat, shown above. */
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")
	
	
	/* Finally, let's start trying to figure out if the supplied address is
	   valid. */
	
	/* Begin with the coarse pattern to simply break up user@domain into
	   different pieces that are easy to analyze. */
	var matchArray=emailStr.match(emailPat)
	if (matchArray==null) {
	  /* Too many/few @'s or something; basically, this address doesn't
	     even fit the general mould of a valid e-mail address. */
		alert("Email address seems incorrect (check @ and .'s)")
		return false
	}
	var user=matchArray[1]
	var domain=matchArray[2]
	
	// See if "user" is valid 
	if (user.match(userPat)==null) {
	    // user is not valid
	    alert("The username doesn't seem to be valid.")
	    return false
	}
	
	/* if the e-mail address is at an IP address (as opposed to a symbolic
	   host name) make sure the IP address is valid. */
	var IPArray=domain.match(ipDomainPat)
	if (IPArray!=null) {
	    // this is an IP address
		  for (var i=1;i<=4;i++) {
		    if (IPArray[i]>255) {
		        alert("Destination IP address is invalid!")
			return false
		    }
	    }
	    return true
	}
	
	// Domain is symbolic name
	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
		alert("The Domain Name doesn't seem to be valid.")
	    return false
	}
	
	/* domain name seems valid, but now make sure that it ends in a
	   three-letter word (like com, edu, gov) or a two-letter word,
	   representing country (uk, nl), and that there's a hostname preceding 
	   the domain or country. */
	
	/* Now we need to break up the domain to get a count of how many atoms
	   it consists of. */
	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) {
	   // the address must end in a two letter or three letter word.
	   alert("The address must end in a three-letter domain, or two letter country.")
	   return false
	}
	
	// Make sure there's a host name preceding the domain.
	if (len<2) {
	   var errStr="This E-mail address is missing a hostname!"
	   alert(errStr)
	   return false
	   }
	   // If we've gotten this far, everything's valid!
	return true	   
}
// end o