function encryptPassword($pwElem) {
    var $pw = $pwElem.value;
    var $pwencrypt = sha256_digest($pw);
    $pwElem.value = $pwencrypt;
}

var loginSuccessTarget = "";

function login(uname, pw) {
    var pwencrypt = sha256_digest(pw);
    var vars = "&uname="+uname+"&pw="+pwencrypt;
    ajax("login.php", vars, handleLogin);
}

function handleLogin(resultContents) {
    var results = resultContents.split(",");
    if (results[0]=="1") {
        // succeeded - swap out the login section of the header
        var loginDiv = document.getElementById("logindiv");
        loginDiv.style.display = "none";

        var logoutdiv = document.getElementById("logoutdiv");
        logoutdiv.style.display = "";

        var username = results[1];
        var usernameSpan = document.getElementById("loggedinname");
        if (usernameSpan != null) {
            usernameSpan.innerHTML = username;
        }
        // Refresh the current page
        if (loginSuccessTarget == "") {
            window.location.reload( true );
        } else {
            window.location.href = loginSuccessTarget;
        }
    } else {
        alert("Bad user name or password");
    }
}

function logout() {
    ajax("logout.php", "", handleLogout);
}

function handleLogout(resultContents) {
    var results = resultContents.split(",");
    if (results[0]=="1") {
        var loginDiv = document.getElementById("logindiv");
        var logoutdiv = document.getElementById("logoutdiv");
        var passwordField = document.getElementById("pw");
        logoutdiv.style.display = "none";
        loginDiv.style.display = "";
        passwordField.value = "";
    }
    // Refresh the current page
    window.location.reload( true );
}