Plexamp NUC LED status display

plexamp_nuc_led.py

#!/usr/bin/env python3

"""
Uses [intel-nuc-led](https://github.com/pmenke-de/intel-nuc-led) to control the LED ring light
on a NUC, to reflect the current status of a runnung Plexamp instance as well as shairport-sync.
-> For use with a NUC as headless Plexamp-player, controlled via another Plexamp instance on a smartphone.
"""

import nuc_wmi
from nuc_wmi.set_led import set_led
import xml.etree.ElementTree as ET
import requests
import time
import dbus


SHAIRPORT_BUS_NAME = "org.gnome.ShairportSync"
SHAIRPORT_OBJECT_PATH = "/org/gnome/ShairportSync"
SHAIRPORT_INTERFACE = "org.gnome.ShairportSync"
DBUS_PROPERTIES_IFACE = "org.freedesktop.DBus.Properties"


def is_airplay_active() -> bool:
    """
    Equivalent to:
      dbus-send --print-reply --system --dest=org.gnome.ShairportSync \
        /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get \
        string:org.gnome.ShairportSync string:Active
    """
    try:
        bus = dbus.SystemBus()
        proxy = bus.get_object(SHAIRPORT_BUS_NAME, SHAIRPORT_OBJECT_PATH)
        props = dbus.Interface(proxy, DBUS_PROPERTIES_IFACE)
        active = props.Get(SHAIRPORT_INTERFACE, "Active")
        return bool(active)
    except Exception:
        # If ShairportSync isn't running / D-Bus not available, treat as inactive
        return False


def main():
    last_change = time.time()
    last_state = "unknown"

    while True:
        loop_start = time.time()

        # Default: error/unknown
        color = "Red"
        freq = "0.25Hz fade"
        brightness = 20

        # AirPlay overrides everything else
        if is_airplay_active():
            state = "airplay"
            color = "Blue"
            freq = "Always on"
        else:
            url = "http://localhost:32500/player/timeline/poll?wait=1&includeMetadata=0&commandID=1"
            state = "unknown"
            try:
                res = requests.get(url)
                if res.ok:
                    root = ET.fromstring(res.content)
                    for type_tag in root.findall('Timeline'):
                        item_type = type_tag.get('itemType')
                        if item_type == "music":
                            state = type_tag.get('state')
                            match state:
                                case "playing":
                                    color = "Green"
                                    freq = "Always on"
                                case "paused":
                                    color = "Yellow"
                                    freq = "0.25Hz fade"
                                case "stopped":
                                    color = "Yellow"
                                    freq = "Always on"
                                case _:
                                    print("bad state: " + state)
                                    color = "Red"
                        break
                else:
                    state = "error"
                    print("bad response: " + str(res.content))
            except Exception as e:
                state = "error"
                print(e)
                pass  # color is red

        if last_state != state:
            last_change = time.time()
            last_state = state
        elif time.time() - last_change > 30:
            # dim after 30s (including for AirPlay)
            brightness = 1
            freq = "Always on"

        set_led(
            nuc_wmi.LED_TYPE["legacy"].index("S0 Ring LED"),
            brightness,
            nuc_wmi.LED_BLINK_FREQUENCY["legacy"].index(freq),
            nuc_wmi.LED_COLOR['legacy'][nuc_wmi.LED_COLOR_TYPE['legacy']["S0 Ring LED"]].index(color)
        )

        if time.time() - loop_start < .5:
            time.sleep(0.5)


if __name__ == "__main__":
    while True:
        main()