Homekit button to play radio stream on chromecast

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Hi All,

I have HA running on a synology NAS, with homebridge connecting to Homekit.
As mediaplayers I have 3 Google Home devices.
I wanted a button in Homekit that plays a specific radio stream (URL) to a specific Google Home device.
I got this working by creating a script that is pushed to homekit as a dumb button:

'1546443759261':
  alias: QMusic_keuken
  sequence:
  - service: media_player.play_media
    data_template:
      entity_id: media_player.keuken
      media_content_id: http://icecast-qmusic.cdp.triple-it.nl/Qmusic_be_live_128.mp3
      media_content_type: audio/mp4

Now I was wondering,
How could I make a switch, that runs this script, but the button state is polled by the status of media_player.keuken.
And when switched off, it runs another script:

'1546444354459':
  alias: Radio_OFF
  sequence:
  - data: {}
    service: media_player.media_stop

Can this be done?

Many thanks