function validate_username_form(minlength) {
    var user = validate_username();
    var pass = validate_password(minlength);

    if (validate_confirm() && pass && user) {
        disable_submit(false);
        return true;
    }

    disable_submit(true);
    return false;
}

function disable_submit(status) {
    document.getElementById("submit").disabled = status;
}

function validate_email() {
    var email = document.getElementById("email");
    var re = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;

    if (re.test(email.value) != true) {
        disable_submit(true);
        email.classList.add("errorinput");
        return false;
    }


    disable_submit(false);
    email.classList.remove("errorinput");
    return true;
}

function validate_confirm() {
    var password = document.getElementById("newpassword");
    var confirm = document.getElementById("confirm_password");

    if (password.value != confirm.value) {
        confirm.classList.add("errorinput");
        document.getElementById("confirm-msg").classList.add("errormsg");
        return false;
    }

    confirm.classList.remove("errorinput");
    document.getElementById("confirm-msg").classList.remove("errormsg");

    return true;
}

function validate_username() {
    var username = document.getElementById("username");
    var forbidden = /[*?!'\^+%\&/()=}{\$#;,\\"]+/;

    if (username.value.length > 64 || forbidden.test(username.value) == true) {
        document.getElementById("username-msg").classList.add("errormsg");
        username.classList.add("errorinput");
        disable_submit(true);
        return false;
    }

    document.getElementById("username-msg").classList.remove("errormsg");
    username.classList.remove("errorinput");
    disable_submit(false);
    return true;
}

function validate_password(minlength) {
    // Did the checks pass ?
    var status = true;
    // Target element
    var password = document.getElementById("newpassword");
    // Check the length
    if (password.value.length < minlength) {
        status = false;
        document.getElementById("minlen").classList.add("errormsg");
    }
    else
        document.getElementById("minlen").classList.remove("errormsg");
    // Look for a digit
    if (/.*\d/.test(password.value) != true) {
        status = false;
        document.getElementById("digit").classList.add("errormsg");
    }
    else
        document.getElementById("digit").classList.remove("errormsg");
    // Look for a lowercase char
    if (/.*[a-z]/.test(password.value) != true) {
        status = false;
        document.getElementById("lower").classList.add("errormsg");
    }
    else
        document.getElementById("lower").classList.remove("errormsg");
    // Look for an uppercase char
    if (/.*[A-Z]/.test(password.value) != true) {
        status = false;
        document.getElementById("upper").classList.add("errormsg");
    }
    else
        document.getElementById("upper").classList.remove("errormsg");

    // Change the color of the inputbox
    if (status == false)
        password.classList.add("errorinput");
    else
        password.classList.remove("errorinput");

    return status;
}