{ lib
, runCommand
, gsettings-desktop-schemas
, gnome-shell
, glib
, gnome-flashback
, nixos-artwork
, nixos-background-light ? nixos-artwork.wallpapers.simple-blue
, nixos-background-dark ? nixos-artwork.wallpapers.simple-dark-gray
, extraGSettingsOverrides ? ""
, extraGSettingsOverridePackages ? [ ]
, favoriteAppsOverride ? ""
, flashbackEnabled ? false
}:

let

  inherit (lib) concatMapStringsSep;

  gsettingsOverridePackages = [
    gsettings-desktop-schemas
    gnome-shell
  ] ++ lib.optionals flashbackEnabled [
    gnome-flashback
  ] ++ extraGSettingsOverridePackages;

  gsettingsOverrides = ''
    [org.gnome.desktop.background]
    picture-uri='file://${nixos-background-light.gnomeFilePath}'
    picture-uri-dark='file://${nixos-background-dark.gnomeFilePath}'

    [org.gnome.desktop.screensaver]
    picture-uri='file://${nixos-background-dark.gnomeFilePath}'

    ${favoriteAppsOverride}

    ${extraGSettingsOverrides}
  '';

in

runCommand "gnome-gsettings-overrides" { preferLocalBuild = true; } ''
  data_dir="$out/share/gsettings-schemas/nixos-gsettings-overrides"
  schema_dir="$data_dir/glib-2.0/schemas"
  mkdir -p "$schema_dir"

  ${concatMapStringsSep "\n" (pkg: "cp -rf \"${glib.getSchemaPath pkg}\"/*.xml \"${glib.getSchemaPath pkg}\"/*.gschema.override \"$schema_dir\"") gsettingsOverridePackages}

  chmod -R a+w "$data_dir"
  cat - > "$schema_dir/zz-nixos-defaults.gschema.override" <<- EOF
  ${gsettingsOverrides}
  EOF

  ${glib.dev}/bin/glib-compile-schemas --strict "$schema_dir"
''