Reapply "nixos/pipewire: minor refactor" (#537898)

nixos/modules/services/desktops/pipewire/pipewire.nix

@@ -11,11 +11,17 @@ let
   inherit (lib) maintainers teams;
   inherit (lib.attrsets)
     attrByPath
-    attrsToList
     concatMapAttrs
     filterAttrs
+    mapAttrs'
+    nameValuePair
+    ;
+  inherit (lib.lists)
+    elem
+    flatten
+    optional
+    optionals
     ;
-  inherit (lib.lists) flatten optional optionals;
   inherit (lib.modules) mkIf mkRemovedOptionModule;
   inherit (lib.options)
     literalExpression
@@ -23,7 +29,7 @@ let
     mkOption
     mkPackageOption
     ;
-  inherit (lib.strings) concatMapStringsSep hasPrefix optionalString;
+  inherit (lib.strings) hasPrefix optionalString;
   inherit (lib.types)
     attrsOf
     bool
@@ -32,17 +38,6 @@ let
     ;
 
   json = pkgs.formats.json { };
-  mapToFiles =
-    location: config:
-    concatMapAttrs (name: value: {
-      "share/pipewire/${location}.conf.d/${name}.conf" = json.generate "${name}" value;
-    }) config;
-  extraConfigPkgFromFiles =
-    locations: filesSet:
-    pkgs.runCommand "pipewire-extra-config" { } ''
-      mkdir -p ${concatMapStringsSep " " (l: "$out/share/pipewire/${l}.conf.d") locations}
-      ${concatMapStringsSep ";" ({ name, value }: "ln -s ${value} $out/${name}") (attrsToList filesSet)}
-    '';
   cfg = config.services.pipewire;
   enable32BitAlsaPlugins =
     cfg.alsa.support32Bit && pkgs.stdenv.hostPlatform.isx86_64 && pkgs.pkgsi686Linux.pipewire != null;
@@ -58,11 +53,24 @@ let
 
   configPackages = cfg.configPackages;
 
-  extraConfigPkg = extraConfigPkgFromFiles [ "pipewire" "client" "jack" "pipewire-pulse" ] (
-    mapToFiles "pipewire" cfg.extraConfig.pipewire
-    // mapToFiles "client" cfg.extraConfig.client
-    // mapToFiles "jack" cfg.extraConfig.jack
-    // mapToFiles "pipewire-pulse" cfg.extraConfig.pipewire-pulse
+  extraConfigPkg = pkgs.linkFarm "pipewire-extra-config" (
+    concatMapAttrs
+      (
+        location: config:
+        mapAttrs' (
+          name: value:
+          nameValuePair "share/pipewire/${location}.conf.d/${name}.conf" (json.generate name value)
+        ) config
+      )
+      # cfg.extraConfig contains deprecated options, i.e. client-rt
+      {
+        inherit (cfg.extraConfig)
+          pipewire
+          client
+          jack
+          pipewire-pulse
+          ;
+      }
   );
 
   configs = pkgs.buildEnv {