var kwDefault     = "";
var selectedModel = "";

function init()
{
    kwDefault = $("kwDefault").innerHTML;
    selectedModel = $("modelSelected").innerHTML;
    aEvent($("make"), 'change', refreshModelsList);
    refreshModelsList();
    aEvent($("kw"), 'focus', kw_focus);
    aEvent($("kw"), 'blur',  kw_blur);

    $("kw").blur();
    kw_blur();
    aEvent($("searchForm"), 'submit', onFormSubmit);
}

function kw_focus()
{
    $("kw").style.fontStyle='normal';
    if ( $("kw").value == kwDefault )
    {
        $("kw").value = '';
    }
    else
    {
        $("kw").select();
    };
}

function kw_blur()
{
    if ( $("kw").value == '' )
    {
        $("kw").style.fontStyle = 'italic';
        $("kw").value = kwDefault;
    }
}

function updateModelsList(trans)
{
    models = eval(trans.responseText || trans.responseBody);
    model = $('model');
    model.disabled = false;
    o = model.options[0];
    model.options.length = 0;
    model.options.add(o);
    for ( var i = 0; i < models.length; i++ )
    {
        o = document.createElement("OPTION");
        model.options.add(o);
        o.value     = models[i].id;
        o.innerHTML = models[i].name;
        if ( o.value == selectedModel )
        {
            o.selected="true";
        }
    }
}

function refreshModelsList()
{
    $('model').disabled = true;
    $('model').value = '';
    if ( $('make').value == '' )
    {
        return;
    }

    var ajax = new AJAX();
    var requestOptions = {
        method    : "GET",
        url       : "get_models.php?maker=" + $("make").value,
        onSuccess : updateModelsList,
        onError   : null
    }
    ajax.request(requestOptions, true);
}

function onFormSubmit()
{
    if ( $("kw").value == kwDefault )
    {
        $("kw").value = "";
    }
}