Descrease brightness

var entity = msg.data.entity_id
var brightness = msg.data.attributes.brightness

brightness = parseInt(brightness);

if (brightness > 76) {
    brightness = brightness - 75;
} else {
    brightness = 1;
}

var new_payload = '{"data":{"entity_id":"' + entity + '","brightness":' + brightness.toString() + '}}'
msg.payload = new_payload;
return msg;