//check browser
var detect = navigator.userAgent.toLowerCase();
var OSBrowser;

function checkIt(string){
	place = detect.indexOf(string) + 1;
	thestring = string;
	return place;
}

function checkBrowser(){
	if (!OSBrowser)
	{
		if (checkIt('linux')) OSBrowser = "Linux";
		else if (checkIt('x11')) OSBrowser = "Unix";
		else if (checkIt('mac')) OSBrowser = "Mac"
		else if (checkIt('win')) OSBrowser = "Windows"
		else OSBrowser = "an unknown operating system";
	}
}
		
function validnumber(){
	event.returnValue = (event.keyCode>=48 && event.keyCode<=57); 
}

function submitMail(){
	var objEmail;
	objEmail=document.getElementById(arguments[0]).value.trim();
	
	if(objEmail=='Add your email address'||objEmail==''){
		alert('Please enter your email address.');
		return false;
	}else{
		//check invalid email address
		var str = document.getElementById(arguments[0]).value.trim();
		var emailReg = "^[\\w-_\.]*[\\w-_\.]\@[\\w]\.+[\\w]+[\\w]$";
		var regex = new RegExp(emailReg);

		if (!regex.test(str)){
			return false;
		}else
		{
			__doPostBack(arguments[0],'');
			
			//enable validator
			for(var i=0; i< Page_Validators.length; i++ ) {
				ValidatorValidate(Page_Validators[i]);
			}	
				
			return true;
		}
	}
}

function submitBlog(){
	var objTitle,objBody,objFTTitle,objFTBody,blnValid;
	objTitle=document.getElementById(arguments[1]);
	objBody=document.getElementById(arguments[2]);
	objFTTitle=document.getElementById(arguments[3]);
	objFTBody=document.getElementById(arguments[4]);
	
	blnValid=true;
	
	if(objTitle.value.trim()==''){
		alert('Please enter title.');
		objTitle.focus();
		blnValid=false;	
	}
	else if(objBody.value.trim()==''){
		alert('Please enter your content.');
		objBody.focus();
		blnValid=false;	
	}
	
	if(blnValid){
		objTitle.value=objFTTitle.value;
		objBody.value=objFTBody.value;
		
		__doPostBack(arguments[0],'');
			
		//enable validator
		for(var i=0; i< Page_Validators.length; i++ ) {
			ValidatorValidate(Page_Validators[i]);
		}	
	}
	
	return blnValid;
}

function loginSystem(){
	var objUserName,objUserPassword,blnValid;
	objUserName=document.getElementById(arguments[1]);
	objUserPassword=document.getElementById(arguments[2]);
	
	blnValid=true;
	
	if(objUserName.value.trim()==''){
		alert('Please enter your username.');
		objUserName.focus();
		blnValid=false;	
	}
	else if(objUserPassword.value.trim()==''){
		alert('Please enter your user password.');
		objUserPassword.focus();
		blnValid=false;	
	}
	
	if(blnValid){
		__doPostBack(arguments[0],'');
			
		//enable validator
		for(var i=0; i< Page_Validators.length; i++ ) {
			ValidatorValidate(Page_Validators[i]);
		}	
	}
	
	return blnValid;
}

function submitSearch(){
	var objSearch;
	objSearch=document.getElementById(arguments[0]);
	
	if(objSearch.value.trim()==''){
		alert('Please enter your search keyword.');
		objSearch.focus();
		return false;
	}else{
		__doPostBack(arguments[0],'');
			
		//enable validator
		for(var i=0; i< Page_Validators.length; i++ ) {
			ValidatorValidate(Page_Validators[i]);
		}	
			
		return true;
	}
}

function clearEmail(){
	var objEmail;
	objEmail=document.getElementById(arguments[0]);
	
	if(objEmail.value.trim()=='Add your email address'){
		objEmail.value='';
	}
}

function resetEmail(){
	var objEmail;
	objEmail=document.getElementById(arguments[0]);
	
	if(objEmail.value.trim()==''){
		objEmail.value='Add your email address';
	}
}

String.prototype.trim = function()    //// trims white space off both ends of this string
{
		return( (ar=/^\s*([\s\S]*\S+)\s*$/.exec(this)) ? ar[1] : "" ); 
}

//validate date dd/mm/yyyy
var dtCh= "/";
var minYear=1900;
var maxYear=3000;

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 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++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
	for (var i = 1; i <= n; i++) {
		this[i] = 31
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30}
		if (i==2) {this[i] = 29}
   } 
   return this
}

function isDate(dtStr){
	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var pos2=dtStr.indexOf(dtCh,pos1+1)
	var strDay=dtStr.substring(0,pos1)
	var strMonth=dtStr.substring(pos1+1,pos2)
	var strYear=dtStr.substring(pos2+1)
	strYr=strYear
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
	}
	month=parseInt(strMonth)
	day=parseInt(strDay)
	year=parseInt(strYr)
	if (pos1==-1 || pos2==-1){
		//alert("The date format should be : dd/mm/yyyy")
		return false
	}
	if (strMonth.length<1 || month<1 || month>12){
		//alert("Please enter a valid month")
		return false
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		//alert("Please enter a valid day")
		return false
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		//alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		//alert("Please enter a valid date")
		return false
	}
return true
}

//mm/yyyy
function isDateShort(dtStr){
	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var strMonth=dtStr.substring(0,pos1)
	var strYear=dtStr.substring(pos1+1,dtStr.length)
	strYr=strYear
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
	}
	month=parseInt(strMonth)
	year=parseInt(strYr)
	
	if (pos1==-1){
		//alert("The date format should be : mm/yyyy")
		return false
	}
	if (strMonth.length<1 || month<1 || month>12){
		//alert("Please enter a valid month")
		return false
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		//alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false
	}
	
return true
}

//end validate date