nixos: repair xwayland socket before steam

nixos/games.nix

@@ -1,13 +1,55 @@
 {
   config,
+  lib,
   pkgs,
   makeEnable,
   ...
-}:
-makeEnable config "myModules.games" false {
-  environment.systemPackages = with pkgs; [
-    steam
-    heroic
-  ];
-  hardware.xone.enable = true;
-}
+}: let
+  repairXwaylandSocket = pkgs.writeShellApplication {
+    name = "repair-xwayland-socket";
+    text = ''
+      if [ -z "''${DISPLAY:-}" ]; then
+        exit 0
+      fi
+
+      display_part="''${DISPLAY#*:}"
+      display_number="''${display_part%%.*}"
+      case "$display_number" in
+        ""|*[!0-9]*) exit 0 ;;
+      esac
+
+      socket="/tmp/.X11-unix/X$display_number"
+      fallback_socket="''${socket}_"
+
+      if [ -S "$socket" ]; then
+        exit 0
+      fi
+
+      if [ -L "$socket" ] && [ ! -e "$socket" ]; then
+        rm -f "$socket" 2>/dev/null || true
+      fi
+
+      if [ ! -e "$socket" ] && [ -S "$fallback_socket" ]; then
+        ln -s "X''${display_number}_" "$socket" 2>/dev/null || true
+      fi
+    '';
+  };
+  steamWithXwaylandSocketRepair = pkgs.symlinkJoin {
+    name = "steam-with-xwayland-socket-repair";
+    paths = [pkgs.steam];
+    nativeBuildInputs = [pkgs.makeWrapper];
+    postBuild = ''
+      rm -f "$out/bin/steam"
+      makeWrapper ${pkgs.steam}/bin/steam "$out/bin/steam" \
+        --run ${lib.escapeShellArg "${repairXwaylandSocket}/bin/repair-xwayland-socket"}
+    '';
+  };
+in
+  makeEnable config "myModules.games" false {
+    environment.systemPackages = with pkgs; [
+      repairXwaylandSocket
+      steamWithXwaylandSocketRepair
+      heroic
+    ];
+    hardware.xone.enable = true;
+  }