<script type="text/javascript" >
    function calcul() {
        var Cristal = document.forms['trader'].elements['cristal'].value;
        var Deuterium = document.forms['trader'].elements['deut'].value;

        Cristal = Cristal * {mod_ma_res_a};
        Deuterium = Deuterium * {mod_ma_res_b};

        var Metal = Cristal + Deuterium;
        document.getElementById("met").innerHTML = Metal;

        if (isNaN(document.forms['trader'].elements['cristal'].value)) {
            document.getElementById("met").innerHTML = "S�lo n�meros";
        }
        if (isNaN(document.forms['trader'].elements['deut'].value)) {
            document.getElementById("met").innerHTML = "S�lo n�meros";
        }
    }
</script>
<br />
<div id="content">
    <h2 class="overview-title">Mercader</h2>
    <form id="trader" action="" method="post">
        <input type="hidden" name="ress" value="metal">
        <table width="569">
            <tr>
                <td class="c" colspan="5"><b>{tr_sell_metal}</b></td>
            </tr><tr>
                <th>{tr_resource}</th>
                <th>{tr_amount}</th>
                <th>{tr_quota_exchange}</th>
            </tr><tr>
                <th>{Metal}</th>
                <th><span id='met'></span>&nbsp;</th>
                <th>{mod_ma_res}</th>
            </tr><tr>
                <th>{Crystal}</th>
                <th><input name="cristal" type="text" value="0" onkeyup="calcul()"/></th>
                <th>{mod_ma_res_a}</th>
            </tr><tr>
                <th>{Deuterium}</th>
                <th><input name="deut" type="text" value="0" onkeyup="calcul()"/></th>
                <th>{mod_ma_res_b}</th>
            </tr><tr>
                <th colspan="6"><input type="submit" value="{tr_exchange}" /></th>
            </tr>
        </table>
    </form>
</div>