Turn on with upcoming alarm

var next_alarm_entity = "sensor.derek_s20_next_alarm"
var person_or_device_entity = "person.derek"
//20-30 minutes for real-world; 600 minutes for testing
var how_many_minutes_before_alarm = 30
var entity_to_adjust_based_on_alarm = "light.bedroom1"


msg.payload = null;
var d = global.get('homeassistant').homeAssistant
var next_alarm = d.states[next_alarm_entity].state
var who = d.states[person_or_device_entity].state
function map(x, in_min, in_max, out_min, out_max)
{
    return Math.round((x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min);
}

var entity_current_brightness = d.states[entity_to_adjust_based_on_alarm].attributes.brightness
var entity_current_state = d.states["light.bedroom1"].state
var time_now_unix = new Date().getTime();
var next_alarm_unix = new Date(next_alarm).getTime();
var how_long_until_next_alarm_in_minutes = ((next_alarm_unix - time_now_unix) / 60000).toFixed()

// Check if home and within number of minutes before alarm
if (who === "Home" && how_long_until_next_alarm_in_minutes <= how_many_minutes_before_alarm) {

    //convert the percentage of minutes until alarm compared to variable how_many_minutes_before_alarm
    //and then set to scale of 0 to 255 for brightness attribute
    var brightness = ((1 - (how_long_until_next_alarm_in_minutes / how_many_minutes_before_alarm)) * 100).toFixed()
    brightness = map(brightness, 0, 100, 0, 255);


    //Check if current brightness is less than brightness variable or undefined (off)
    if (entity_current_brightness < brightness || entity_current_brightness === undefined) {
        msg.payload = {domain: "light", service: "turn_on", data: {
            entity_id: entity_to_adjust_based_on_alarm,
            brightness: brightness,
            //kelvin: null }
            }
        };
        msg.payload.entity_id = entity_to_adjust_based_on_alarm;

        node.status({text: "Within range; adjusting brightness to " + brightness});
        return msg;

    } else {

        //The brightness is already brighter than what script is wanting to adjust it to
        node.status({text: "Within range but not adjusting brightness"});

    }

} else {

    //.status({text: "Not time yet; flow halted"});
    node.status({text: how_long_until_next_alarm_in_minutes + " minutes until alarm"});
    //node.status({text: how_long_until_next_alarm_in_minutes});
}