function imageChanger(imgName, imgKey) {
    if (document.images) {
        document[imgName].src = "images/buttons/" + imgKey;
    }
}

function validMaintRequestMessage() {
    var visitorNameValue = document.getElementById("visitorName2").value;
    var emailAddressValue = document.getElementById("visitorEmail2").value;
    var notesValue = document.getElementById("notes2").value;
    return validater(visitorNameValue, emailAddressValue, notesValue, "Missing Maintenance Description.  Please enter a description of your maintenance request. Thanks");
}

function validDefaultMessage() {
    var visitorName = document.getElementById("visitorName1").value;
    var emailAddress = document.getElementById("visitorEmail1").value;
    var notes = document.getElementById("notes1").value;
    return validater(visitorName, emailAddress, notes, "");
}

function validater(name, address, notes, customString) {
    if (name == "") {
        alert("Missing Name. Please enter your name. Thanks");
        return false;
    } else if (!isValidEmailAddress(address)) {
        alert("Invalid Email Address. Please enter a valid email address")
        return false;
    } else if (address == "") {
        alert("Missing Email Address.  Please enter an email address. Thanks");
        return false;
    } else if (notes == "") {
        if (customString == "")
            alert("Missing Message.  Please enter a message. Thanks");
        else
            alert(customString);
        return false;
    } else {
        return true;
    }
}

function isValidEmailAddress(emailAddress) {
    if (emailAddress.indexOf("@") > 0 && emailAddress.indexOf(".") > 0) {
        return true;
    } else {
        return false;
    }
}