install steam using brew on macos

home-modules/brew.nix

@@ -1,6 +1,8 @@
 { config, lib, pkgs, ... }:
 
-{
+let
+  brewPath = config.homebrew.brewPath;
+in {
   options.lumpiastyHome.brew = lib.mkEnableOption "Homebrew integration via home-manager-brew";
 
   config = lib.mkMerge [
@@ -15,6 +17,18 @@
           "steam"
         ];
       };
+
+      home.activation.homebrewInstall = lib.mkForce (
+        lib.hm.dag.entryAfter ["installPackages" "linkGeneration" "createGpgHomedir"] (
+          if config.homebrew.brewInstall then ''
+            if [ ! -f "${brewPath}" ]; then
+              echo "Homebrew not found (${brewPath}), installing..."
+              export PATH="${pkgs.curl}/bin:${pkgs.bash}/bin:${pkgs.coreutils}/bin:${pkgs.gnugrep}/bin:${pkgs.gnused}/bin:$PATH"
+              ${pkgs.bash}/bin/bash -c "$(${pkgs.curl}/bin/curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+            fi
+          '' else ""
+        )
+      );
     })
     (lib.mkIf (!config.lumpiastyHome.brew) {
       homebrew.enable = lib.mkForce false;