starsector: discussion about settings.json

Hello! Starsector has a special settings file "settings.json" that has a lot of useful options, such as the option to force a specific resolution (it would be useful for me bacause I have two monitors, and starsector reads the possible resolutions from the wrong one).

However, in the nixpkgs version, this file is part of the derivation in /nix/store/.....-starsector-.../share/starsector/data/config/settings.json, thus impossible to edit.

I tried scratching a basic PR to allow settings to be passed as a derivation argument but I hit into some issues: The JSON used by starsector is far from standard. Not only it has comments, it also has java-style floats, with the 'f' suffix. So, I was not able to process into a nix attrset that could be modified and then converted back into a new settings.json file. I tried using some external tools such as jq and hjson, but the floats just break them.

Here is my non-functional code to illustrate the idea:

  installPhase =
    let
      sanitesedSettings = runCommandLocal "settings.json" { } ''
          # Filtering could happen here too
         cp "${src}/data/config/settings.json" $out
      '';

      defaultSettings = lib.pipe sanitesedSettings [
        builtins.readFile
        (s: lib.splitString "\r\n" s)
        (ss: lib.filter (s: (builtins.match "^[[:space:]]*#.*$" s) == null) ss) # Delete comment lines
        lib.concatLines
        builtins.fromJSON # errors here because it is not valid JSON
      ];

      # The idea would be to merge the defaultSettings above with a settings argument passed to the derivation
      settingsFile = writeText "settings.json" (builtins.toJSON (defaultSettings // settings));
    in
    '' ... '';

Have any of you thought about this? Do you have any ideas?

Pinging my fellow starsector maintaners: @bbigras @sigmasquadron

Start with the Starsector package derivation and its bundled data/config/settings.json; review the non-functional Nix example in the issue and how the derivation currently installs this file. Determine a supported way to expose configurable settings despite comments and Java-style float suffixes, with completion demonstrated by an editable generated settings.json in the package.