/*
 * Returns true if the specified field is not empty, otherwise false.
 */
function validateNotEmpty(fieldId, tickId) {
    var field = $(fieldId);
    var valid = false;
    if(field!=null) {
        var fieldValue = $(fieldId).val();
        valid = fieldValue!=null && fieldValue.length>0;
    }
    markFieldValidity(fieldId,valid);
    tick(valid,tickId);
    return valid;
}


/*
 * Returns true if the specified field contains a valid integer.
 */
function validateInteger(fieldId, tickId) {
    var valid = false;
    if(validateNotEmpty(fieldId)) {
        val = parseInt($(fieldId).val());
        valid = val<=0 || val>0;
    }
    markFieldValidity(fieldId,valid);
    tick(valid,tickId);
    return valid;
}


/*
 * Returns true if the specified checkbox field is checked.
 */
function validateChecked(fieldId, tickId) {
    var checkedVal = $(fieldId).attr("checked");
    var valid = checkedVal && checkedVal.val() == "checked";
    markFieldValidity(fieldId,valid);
    tick(valid,tickId);
    return valid;
}


/*
 * Returns true if the specified select field has a valid value other than the
 * default "--".
 */
function validateSelection(fieldId, tickId) {
    var valid = false;
    if(validateNotEmpty(fieldId)) {
        var value = $(fieldId).val();
        valid = value!="--";
    }
    markFieldValidity(fieldId,valid);
    tick(valid,tickId);
    return valid;
}


/*
 * Returns true if the specified field contains a valid email address, otherwise
 * false.
 */
var at="@";
var dot=".";
function validateEmailAddress(fieldId, tickId) {
    var notEmpty = validateNotEmpty(fieldId);

    if(notEmpty) {
        var emailStr = $(fieldId).val();
        
        // TLD checking turned off by default
        var checkTLD=0;
        var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
        var emailPat=/^(.+)@(.+)$/;
        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 +")*$");
        var matchArray=emailStr.match(emailPat);
        if (matchArray==null) {
            markFieldValidity(fieldId,false);
            tick(false,tickId);
            return false;
        }
        var user=matchArray[1];
        var domain=matchArray[2];
        for (i=0; i<user.length; i++) {
            if (user.charCodeAt(i)>127) {
                markFieldValidity(fieldId,false);
                tick(false,tickId);
                return false;
            }
        }
        for (i=0; i<domain.length; i++) {
            if (domain.charCodeAt(i)>127) {
                markFieldValidity(fieldId,false);
                tick(false,tickId);
                return false;
            }
        }
        if (user.match(userPat)==null) {
            markFieldValidity(fieldId,false);
            tick(false,tickId);
            return false;
        }
        var IPArray=domain.match(ipDomainPat);
        if (IPArray!=null) {
            for (var i=1;i<=4;i++) {
                if (IPArray[i]>255) {
                    markFieldValidity(fieldId,false);
                    tick(false,tickId);
                    return false;
                }
            }
            markFieldValidity(fieldId,true);
            tick(true,tickId);
            return true;
        }
        var atomPat=new RegExp("^" + atom + "$");
        var domArr=domain.split(".");
        var len=domArr.length;
        for (i=0;i<len;i++) {
            if (domArr[i].search(atomPat)==-1) {
                markFieldValidity(fieldId,false);
                tick(false,tickId);
                return false;
            }
        }
        if (checkTLD && domArr[domArr.length-1].length!=2 && 
            domArr[domArr.length-1].search(knownDomsPat)==-1) {
            markFieldValidity(fieldId,false);
            tick(false,tickId);
            return false;
        }
        if (len<2) {
            markFieldValidity(fieldId,false);
            tick(false,tickId);
            return false;
        }
        markFieldValidity(fieldId,true);
        tick(true,tickId);
        return true;
    }

    markFieldValidity(fieldId,false);
    tick(false,tickId);
    return false;
}


function validateFieldGroup(fieldIds, validators, tickId) {
    if(fieldIds.length!=validators.length) {
        alert("validateFieldGroup fields and validators do not match");
        return;
    }
    
    var validCount = 0;
    for(i=0; i<fieldIds.length; i++) {
        validCount+= markFieldValidity(fieldIds[i],validators[i](fieldIds[i]))? 1 : 0;
    }
    
    tick(validCount==fieldIds.length, tickId);
}


function tick(valid, tickId) {
    if(tickId) {
        if(valid) {
            $(tickId).html('<img src="/images/tick.png">');
        } else {
            $(tickId).html('<img src="/images/cross.png">');
        }
    }
}


/*
 * Marks a field as valid or invalid.  Valid fields are displayed as normal,
 * invalid fields have a visual indication of being invalid.
 */
function markFieldValidity(fieldId, valid) {
    clickTaleRecord("markFieldValidity('"+fieldId+"',"+valid+")");

    if(valid) {
        $(fieldId).attr("class","");
    } else {
        $(fieldId).attr("class","error");
    }
    return valid;
}

/*
 * Filters out non-numeric characters and invokes validation on card number.
 */
function checkNumber(e) {
    e = (e) ? e : event;
    var charCode = (e.charCode) ? e.charCode : ((e.keyCode) ? e.keyCode : ((e.which) ? e.which : 0));
    var number = $(this).val();
    var canReturn;

    if((charCode == 8) || (charCode == 9) || (charCode == 46))
    {
        number = number + String.fromCharCode(charCode);
        canReturn = true;
    } else if((charCode < 48) || (charCode > 57)) {
        canReturn = false;
    } else {
        number = number + String.fromCharCode(charCode);
        canReturn = true;
    }

    return canReturn;
}