function isValidForm(f)
{
    msg = "";

    msg += Check(f.name, "blank", " - Name cannot be blank.\n");
    msg += Check(f.organization, "blank", " - Organization cannot be blank.\n");
	
    if (emailIsValid(f.email.value) == false) {
        msg += " - The Email address you provided is invalid or blank.";
    }

    if (msg == "") {
	    return true;
    } else {
	    alert("Please correct the following:\n\n" + msg);
	    return false;
    }
}

function checkRadio(element, msg) {
    if (radioGroupChecked(element)) {
	    return "";
    } else {
	    return msg;
    }
}

function radioGroupChecked(group) {
    var good = false;
    for (var i = 0; i < group.length; i++) {
	    if (group[i].checked) {
		    good = true;
	    }
    }
    return good;
}

function radioGetValue(group) {
    var output = "";
    for (var i = 0; i < group.length; i++) {
	    if (group[i].checked) {
		    output = group[i].value;
	    }
    }
    return output;
}

function toggleFailure() {
    var f = document.val_form;
    var val = radioGetValue(f.sPointOfFailure);
    f.sPOFOther.disabled = true;
    f.sWhere.disabled = true;
    if (val == "During Use") {
	    f.sWhere.disabled = false;
	    for (var i = 1; i <= 6; i++) {
		    document.getElementById("pof" + i).style.display = "inline";
	    }
    } else {
	    for (var i = 1; i <= 6; i++) {
		    document.getElementById("pof" + i).style.display = "none";
	    }
    }
    if (val == "Other") {
	    f.sPOFOther.disabled = false;
    }
}

function togglePatient() {
    var f = document.val_form;
    var val = radioGetValue(f.sPatientInvolvment);
    if (val == "yes") {
	    for (var i = 2; i <= 6; i++) {
		    document.getElementById("pof" + i).style.display = "inline";
	    }
    } else {
	    for (var i = 2; i <= 6; i++) {
		    document.getElementById("pof" + i).style.display = "none";
	    }
    }
}

function toggleDevice() {
    var f = document.val_form;
    var dev = f.sDevice.value;
    if (dev == "Other") {
	    document.getElementById("prt").style.display = "inline";
	    document.getElementById("devser").style.display = "none";
    } else {
	    document.getElementById("prt").style.display = "none";
	    document.getElementById("devser").style.display = "inline";
    }
    if (dev == "HT50-H1 Ventilator" || dev == "HT50-H Ventilator") {
        document.getElementById("Questionnaire").style.display = "block";
    } else {
        document.getElementById("Questionnaire").style.display = "none";
    }
    if (dev == "e500 Ventilator" || dev == "e500 Graphics Display Monitor(GDM)" || dev == "e360 Ventilator") {
        document.getElementById("swrev").style.display = "inline";
    } else {
        document.getElementById("swrev").style.display = "none";
    }
}

function checkNumber(value, msg) {
    var output = "";
    var allowed = "0123456789-,.";
    for (var i = 0; i < value.length; i++) {
	    if (allowed.indexOf(value.charAt(i)) < 0) {
		    output = msg;
	    }
    }
    return output;
}

function toggleAge() {
    document.val_form.sPatientAge.disabled = document.val_form.UnknownAge.checked;
    if (document.val_form.UnknownAge.checked) {
	    document.val_form.sPatientAge.value = "Unknown";
    } else {
	    document.val_form.sPatientAge.value = "";
    }
}

function toggleNotApplicable() {
    if (document.val_form.bNotApplicable.checked) {
        document.getElementById("question1flag").style.display = "none";
        document.getElementById("question2flag").style.display = "none";
        document.getElementById("question3flag").style.display = "none";
        document.getElementById("question4flag").style.display = "none";
        document.getElementById("question5flag").style.display = "none";
    } else {
        document.getElementById("question1flag").style.display = "inline";
        document.getElementById("question2flag").style.display = "inline";
        document.getElementById("question3flag").style.display = "inline";
        document.getElementById("question4flag").style.display = "inline";
        document.getElementById("question5flag").style.display = "inline";
    }
}

function emailIsValid(str) {

    var at="@"
    var dot="."
    var lat=str.indexOf(at)
    var lstr=str.length
    var ldot=str.indexOf(dot)
    if (str.indexOf(at)==-1){
       return false
    }
    if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
       return false
    }
    if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
        return false
    }
    if (str.indexOf(at,(lat+1))!=-1){
        return false
    }
    if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
        return false
    }
    if (str.indexOf(dot,(lat+2))==-1){
        return false
    }
    if (str.indexOf(" ")!=-1){
        return false
    }

    return true					
}