{{ $out := "" }}
{{ if hasPrefix . "https://open.spotify.com/track/" }}
  {{ $out = (printf "https://song.link/s/%s" (substr . 31)) }}
{{ else if hasPrefix . "https://open.spotify.com/album/" }}
  {{ $out = (printf "https://song.link/s/%s" (substr . 31)) }}
{{ else if hasPrefix . "https://open.spotify.com/" }}
  {{/* Spotify artists, users & playlists *must* go to spotify */}}
  {{ $out = . }}
{{else if hasPrefix . "soundcloud:/tracks/"}}
  {{ $out = (printf "https://song.link/sc/%s" (substr . 19)) }}
{{ else }}
  {{ errorf "Unknown music link: %s" . }}
{{ end }}

{{ return $out }}