users/foo-dogsquared: add quick script for mpv YouTube playlists

users/home-manager/foo-dogsquared/default.nix

@@ -28,6 +28,22 @@ in
 
   home.packages = with pkgs; [
     hledger # Trying to be a good accountant.
+
+    # For now, it is not possible to easily play YouTube playlists until it
+    # is fixed in mpv (or yt-dlp). Ideally, this would be a Python script
+    # but I don't know jack using yt-dlp as a Python module.
+    (pkgs.writeShellApplication {
+      name = "play-mpv-playlist-from-youtube-playlist";
+      runtimeInputs = with pkgs; [
+        config.programs.mpv.package
+        yt-dlp
+      ];
+      text = ''
+        yt-dlp --print id "$1" \
+          | xargs -I{} echo "https://www.youtube.com/watch?v={}" \
+          | mpv --playlist=-
+      '';
+    })
   ];
 
   fonts.fontconfig.enable = true;