function Validator(frmname)
{
this.formobj=document.forms[frmname];
if(!this.formobj)
{
alert("BUG: couldnot get Form object "+frmname);
return;
}
if(this.formobj.onsubmit)
{
this.formobj.old_onsubmit = this.formobj.onsubmit;
this.formobj.onsubmit=null;
}
else
{
this.formobj.old_onsubmit = null;
}
this.formobj.onsubmit=form_submit_handler;
this.addValidation = add_validation;
this.setAddnlValidationFunction=set_addnl_vfunction;
this.clearAllValidations = clear_all_validations;
}
function set_addnl_vfunction(functionname)
{
this.formobj.addnlvalidation = functionname;
}
function clear_all_validations()
{
for(var itr=0;itr < this.formobj.elements.length;itr++)
{
this.formobj.elements[itr].validationset = null;
}
}
function form_submit_handler()
{
for(var itr=0;itr < this.elements.length;itr++)
{
if(this.elements[itr].validationset &&
!this.elements[itr].validationset.validate())
{
return false;
}
}
if(this.addnlvalidation)
{
str =" var ret = "+this.addnlvalidation+"()";
eval(str);
if(!ret) return ret;
}
return true;
}
function add_validation(itemname,descriptor,errstr)
{
if(!this.formobj)
{
alert("BUG: the form object is not set properly");
return;
}//if
var itemobj = this.formobj[itemname];

if(itemobj.length && isNaN(itemobj.selectedIndex) )
//for radio button; don't do for 'select' item
{
itemobj = itemobj[0];
}
if(!itemobj)
{
alert("BUG: Couldnot get the input object named: "+itemname);
return;
}

if(!itemobj.validationset)
{
itemobj.validationset = new ValidationSet(itemobj);
}
itemobj.validationset.add(descriptor,errstr);
}
function ValidationDesc(inputitem,desc,error)
{
this.desc=desc;
this.error=error;
this.itemobj = inputitem;
this.validate=vdesc_validate;
}
function vdesc_validate()
{
if(!validateInput(this.desc,this.itemobj,this.error))
{
this.itemobj.focus();
return false;
}
return true;
}
function ValidationSet(inputitem)
{
this.vSet=new Array();
this.add= add_validationdesc;
this.validate= vset_validate;
this.itemobj = inputitem;
}
function add_validationdesc(desc,error)
{
this.vSet[this.vSet.length]=
new ValidationDesc(this.itemobj,desc,error);
}
function vset_validate()
{
for(var itr=0;itr<this.vSet.length;itr++)
{
if(!this.vSet[itr].validate())
{
return false;
}
}
return true;
}
/*  checks the validity of an email address entered
*   returns true or false
*/
function validateEmail(email)
{
var splitted = email.match("^(.+)@(.+)$");
if(splitted == null) return false;
if(splitted[1] != null )
{
var regexp_user=/^\"?[\w-_\.]*\"?$/;
if(splitted[1].match(regexp_user) == null) return false;
}
if(splitted[2] != null)
{
var regexp_domain=/^[\w-\.]*\.[A-Za-z]{2,4}$/;
if(splitted[2].match(regexp_domain) == null)
{
var regexp_ip =/^\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\]$/;
if(splitted[2].match(regexp_ip) == null) return false;
}// if
return true;
}
return false;
}

function TestComparison(objValue,strCompareElement,strvalidator,strError)
{
var bRet=true;
var objCompare=null;
if(!objValue.form)
{
alert("BUG: No Form object!");
return false
}
objCompare = objValue.form.elements[strCompareElement];
if(!objCompare)
{
alert("BUG: Element with name"+strCompareElement+" not found !");
return false;
}
if(strvalidator != "eqelmnt" &&
strvalidator != "neelmnt")
{
if(isNaN(objValue.value))
{
alert(objValue.name+": Should be a number ");
return false;
}//if
if(isNaN(objCompare.value))
{
alert(objCompare.name+": Should be a number ");
return false;
}//if
}//if
var cmpstr="";
switch(strvalidator)
{
case "eqelmnt":
{
if(objValue.value != objCompare.value)
{
cmpstr = " should be equal to ";
bRet = false;
}//if
break;
}//case
case "ltelmnt":
{
if(eval(objValue.value) >= eval(objCompare.value))
{
cmpstr =  " should be less than ";
bRet = false;
}
break;
}//case
case "leelmnt":
{
if(eval(objValue.value) >  eval(objCompare.value))
{
cmpstr =  " should be less than or equal to";
bRet = false;
}
break;
}//case
case "gtelmnt":
{
if(eval(objValue.value) <=  eval(objCompare.value))
{
cmpstr =  " should be greater than";
bRet = false;
}
break;
}//case
case "geelmnt":
{
if(eval(objValue.value) < eval(objCompare.value))
{
cmpstr =  " should be greater than or equal to";
bRet = false;
}
break;
}//case
case "neelmnt":
{
if(objValue.value.length > 0 &&
objCompare.value.length > 0 &&
objValue.value == objCompare.value)
{
cmpstr = " should be different from ";
bRet = false;
}//if
break;
}
}//switch
if(bRet==false)
{
if(!strError || strError.length==0)
{
strError = objValue.name + cmpstr + objCompare.value;
}//if
alert(strError);
}//if
return bRet;
}
function TestSelMin(objValue,strMinSel,strError)
{
var bret = true;
var objcheck = objValue.form.elements[objValue.name];
var chkcount =0;
if(objcheck.length)
{
for(var c=0;c < objcheck.length;c++)
{
if(objcheck[c].checked == "1")
{
chkcount++;
}//if
}//for
}
else
{
chkcount = (objcheck.checked == "1")?1:0;
}
var minsel = eval(strMinSel);
if(chkcount < minsel)
{
if(!strError || strError.length ==0)
{
strError = "Please Select atleast"+minsel+" check boxes for"+objValue.name;
}//if
alert(strError);
bret = false;
}
return bret;
}

function TestDontSelectChk(objValue,chkValue,strError)
{
var pass=true;
var objcheck = objValue.form.elements[objValue.name];
if(objcheck.length)
{
var idxchk=-1;
for(var c=0;c < objcheck.length;c++)
{
if(objcheck[c].value == chkValue)
{
idxchk=c;
break;
}//if
}//for
if(idxchk>= 0)
{
if(objcheck[idxchk].checked=="1")
{
pass=false;
}
}//if
}
else
{
if(objValue.checked == "1")
{
pass=false;
}//if
}//else
if(pass==false)
{
if(!strError || strError.length ==0)
{
strError = "Can't Proceed as you selected "+objValue.name;
}//if
alert(strError);

}
return pass;
}

function TestRequiredInput(objValue,strError)
{
var ret = true;
if(eval(objValue.value.length) == 0)
{
if(!strError || strError.length ==0)
{
strError = objValue.name + " : Required Field";
}//if
alert(strError);
ret=false;
}//if
return ret;
}

function TestMaxLen(objValue,strMaxLen,strError)
{
var ret = true;
if(eval(objValue.value.length) > eval(strMaxLen))
{
if(!strError || strError.length ==0)
{
strError = objValue.name + " : "+ strMaxLen +" characters maximum ";
}//if
alert(strError + "\n[Current length = " + objValue.value.length + " ]");
ret = false;
}//if
return ret;
}

function TestMinLen(objValue,strMinLen,strError)
{
var ret = true;
if(eval(objValue.value.length) <  eval(strMinLen))
{
if(!strError || strError.length ==0)
{
strError = objValue.name + " : " + strMinLen + " characters minimum  ";
}//if
alert(strError + "\n[Current length = " + objValue.value.length + " ]");
ret = false;
}//if
return ret;
}

function TestInputType(objValue,strRegExp,strError,strDefaultError)
{
var ret = true;

var charpos = objValue.value.search(strRegExp);
if(objValue.value.length > 0 &&  charpos >= 0)
{
if(!strError || strError.length ==0)
{
strError = strDefaultError;
}//if
alert(strError + "\n [Error character position " + eval(charpos+1)+"]");
ret = false;
}//if
return ret;
}

function TestEmail(objValue,strError)
{
var ret = true;
if(objValue.value.length > 0 && !validateEmail(objValue.value)	 )
{
if(!strError || strError.length ==0)
{
strError = objValue.name+": Enter a valid Email address ";
}//if
alert(strError);
ret = false;
}//if
return ret;
}

function TestLessThan(objValue,strLessThan,strError)
{
var ret = true;
if(isNaN(objValue.value))
{
alert(objValue.name+": Should be a number ");
ret = false;
}//if
else
if(eval(objValue.value) >=  eval(strLessThan))
{
if(!strError || strError.length ==0)
{
strError = objValue.name + " : value should be less than "+ strLessThan;
}//if
alert(strError);
ret = false;
}//if
return ret;
}

function TestGreaterThan(objValue,strGreaterThan,strError)
{
var ret = true;
if(isNaN(objValue.value))
{
alert(objValue.name+": Should be a number ");
ret = false;
}//if
else
if(eval(objValue.value) <=  eval(strGreaterThan))
{
if(!strError || strError.length ==0)
{
strError = objValue.name + " : value should be greater than "+ strGreaterThan;
}//if
alert(strError);
ret = false;
}//if
return ret;
}

function TestRegExp(objValue,strRegExp,strError)
{
var ret = true;
if( objValue.value.length > 0 &&
!objValue.value.match(strRegExp) )
{
if(!strError || strError.length ==0)
{
strError = objValue.name+": Invalid characters found ";
}//if
alert(strError);
ret = false;
}//if
return ret;
}
function TestDontSelect(objValue,index,strError)
{
var ret = true;
if(objValue.selectedIndex == null)
{
alert("BUG: dontselect command for non-select Item");
ret = false;
}
else
if(objValue.selectedIndex == eval(index))
{
if(!strError || strError.length ==0)
{
strError = objValue.name+": Please Select one option ";
}//if
alert(strError);
ret =  false;
}
return ret;
}

function TestSelectOneRadio(objValue,strError)
{
var objradio = objValue.form.elements[objValue.name];
var one_selected=false;
for(var r=0;r < objradio.length;r++)
{
if(objradio[r].checked == "1")
{
one_selected=true;
break;
}
}
if(false == one_selected)
{
if(!strError || strError.length ==0)
{
strError = "Please select one option from "+objValue.name;
}
alert(strError);
}
return one_selected;
}

//*  Checks each field in a form
function validateInput(strValidateStr,objValue,strError)
{
var ret = true;
var epos = strValidateStr.search("=");
var  command  = "";
var  cmdvalue = "";
if(epos >= 0)
{
command  = strValidateStr.substring(0,epos);
cmdvalue = strValidateStr.substr(epos+1);
}
else
{
command = strValidateStr;
}

switch(command)
{
case "req":
case "required":
{
ret = TestRequiredInput(objValue,strError)
break;
}
case "maxlength":
case "maxlen":
{
ret = TestMaxLen(objValue,cmdvalue,strError)
break;
}
case "minlength":
case "minlen":
{
ret = TestMinLen(objValue,cmdvalue,strError)
break;
}
case "alnum":
case "alphanumeric":
{
ret = TestInputType(objValue,"[^A-Za-z0-9]",strError,
objValue.name+": Only alpha-numeric characters allowed ");
break;
}
case "alnum_s":
case "alphanumeric_space":
{
ret = TestInputType(objValue,"[^A-Za-z0-9\\s]",strError,
objValue.name+": Only alpha-numeric characters and space allowed ");
break;
}
case "num":
case "numeric":
{
ret = TestInputType(objValue,"[^0-9]",strError,
objValue.name+": Only digits allowed ");
break;
}
case "alphabetic":
case "alpha":
{
ret = TestInputType(objValue,"[^A-Za-z]",strError,
objValue.name+": Only alphabetic characters allowed ");
break;
}
case "alphabetic_space":
case "alpha_s":
{
ret = TestInputType(objValue,"[^A-Za-z\\s]",strError,
objValue.name+": Only alphabetic characters and space allowed ");
break;
}
case "email":
{
ret = TestEmail(objValue,strError);
break;
}
case "lt":
case "lessthan":
{
ret = TestLessThan(objValue,cmdvalue,strError);
break;
}
case "gt":
case "greaterthan":
{
ret = TestGreaterThan(objValue,cmdvalue,strError);
break;
}
case "regexp":
{
ret = TestRegExp(objValue,cmdvalue,strError);
break;
}
case "dontselect":
{
ret = TestDontSelect(objValue,cmdvalue,strError)
break;
}
case "dontselectchk":
{
ret = TestDontSelectChk(objValue,cmdvalue,strError)
break;
}
case "selmin":
{
ret = TestSelMin(objValue,cmdvalue,strError);
break;
}
case "selone":
{
ret = TestSelectOneRadio(objValue,strError);
break;
}
//Comparisons
case "eqelmnt":
case "ltelmnt":
case "leelmnt":
case "gtelmnt":
case "geelmnt":
case "neelmnt":
{
return TestComparison(objValue,cmdvalue,command,strError);
break;
}
}//switch
return ret;
}