From 4ebf259d11930774b3a13b370b955a8765bfcae6 Mon Sep 17 00:00:00 2001
From: Timothy DeHerrera <tim.deh@pm.me>
Date: Thu, 9 Jul 2020 00:05:24 -0600
Subject: [PATCH] modules#steam: create xsession for Steam

---
 modules/list.nix                              |  1 +
 .../services/x11/window-managers/steam.nix    | 45 +++++++++++++++++++
 .../window-managers/steamcompmgr/default.nix  | 34 ++++++++++++++
 pkgs/default.nix                              |  2 +
 profiles/games/default.nix                    |  7 ++-
 5 files changed, 88 insertions(+), 1 deletion(-)
 create mode 100644 modules/services/x11/window-managers/steam.nix
 create mode 100644 pkgs/applications/window-managers/steamcompmgr/default.nix

diff --git a/modules/list.nix b/modules/list.nix
index f517734..6ee0e37 100644
--- a/modules/list.nix
+++ b/modules/list.nix
@@ -3,4 +3,5 @@
   ./security/mitigations.nix
   ./services/hardware/wii-u-gc-adapter.nix
   ./services/games/gamemode.nix
+  ./services/x11/window-managers/steam.nix
 ]
diff --git a/modules/services/x11/window-managers/steam.nix b/modules/services/x11/window-managers/steam.nix
new file mode 100644
index 0000000..948a680
--- /dev/null
+++ b/modules/services/x11/window-managers/steam.nix
@@ -0,0 +1,45 @@
+{ pkgs, lib, config, ... }:
+
+with lib;
+
+let cfg = config.services.xserver.windowManager.steam;
+in {
+  options = {
+    services.xserver.windowManager.steam = {
+      enable = mkEnableOption "steam";
+      package = mkOption {
+        type = lib.types.package;
+        default = pkgs.steam;
+        description = ''
+          The Steam package to use.
+        '';
+      };
+      extraSessionCommands = mkOption {
+        type = lib.types.str;
+        default = "";
+        description = ''
+          Shell commands executed just before Steam is started.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = with pkgs; [ cfg.package ];
+
+    services.xserver.windowManager.session = [{
+      name = "steam";
+      start = ''
+        ${cfg.extraSessionCommands}
+
+        # needed to ensure conflicting compositors are not running
+        ${pkgs.systemd}/bin/systemctl --user stop graphical-session.target
+
+        ${pkgs.xorg.xset}/bin/xset -dpms
+        ${pkgs.xorg.xset}/bin/xset s off
+        ${pkgs.steamcompmgr}/bin/steamcompmgr &
+        steam -tenfoot -fulldesktopres
+      '';
+    }];
+  };
+}
diff --git a/pkgs/applications/window-managers/steamcompmgr/default.nix b/pkgs/applications/window-managers/steamcompmgr/default.nix
new file mode 100644
index 0000000..67b1462
--- /dev/null
+++ b/pkgs/applications/window-managers/steamcompmgr/default.nix
@@ -0,0 +1,34 @@
+{ stdenv, fetchFromGitHub, libudev, SDL, SDL_image, libXdamage, libXcomposite
+, libXrender, libXext, libXxf86vm, pkgconfig, autoreconfHook, gnumake }:
+
+stdenv.mkDerivation {
+  name = "steamcompmgr";
+  src = fetchFromGitHub {
+    owner = "gamer-os";
+    repo = "steamos-compositor-plus";
+    rev = "c3855fcb5015ecdca299ee4b46b9f90c7a6788de";
+    hash = "sha256-sRthjN+pnabl67PuJS+zbUznW4ws0fub0R9bTzelg18=";
+  };
+
+  buildInputs = [
+    libudev
+    SDL
+    SDL_image
+    libXdamage
+    libXcomposite
+    libXrender
+    libXext
+    libXxf86vm
+    pkgconfig
+    autoreconfHook
+    gnumake
+  ];
+
+  meta = with stdenv.lib; {
+    description = "SteamOS Compositor";
+    homepage = "https://github.com/steamos-compositor-plus";
+    maintainers = [ maintainers.nrdxp ];
+    license = licenses.bsd2;
+    inherit version;
+  };
+}
diff --git a/pkgs/default.nix b/pkgs/default.nix
index 4bc8911..f2fdbdd 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -7,4 +7,6 @@ final: prev: {
   wii-u-gc-adapter = prev.callPackage ./misc/drivers/wii-u-gc-adapter { };
   libinih = prev.callPackage ./development/libraries/libinih { };
   gamemode = prev.callPackage ./os-specific/linux/gamemode { };
+  steamcompmgr =
+    prev.callPackage ./applications/window-managers/steamcompmgr { };
 }
diff --git a/profiles/games/default.nix b/profiles/games/default.nix
index faaa272..a364e04 100644
--- a/profiles/games/default.nix
+++ b/profiles/games/default.nix
@@ -2,7 +2,6 @@
   imports = [ ../graphical ./udev.nix ];
   environment.systemPackages = with unstablePkgs; [
     retroarchBare
-    steam
     steam-run
     pcsx2
     qjoypad
@@ -15,6 +14,12 @@
   # fps games on laptop need this
   services.xserver.libinput.disableWhileTyping = false;
 
+  # Launch steam from display managers
+  services.xserver.windowManager.steam = {
+    enable = true;
+    package = unstablePkgs.steam;
+  };
+
   # 32-bit support needed for steam
   hardware.opengl.driSupport32Bit = true;
   hardware.pulseaudio.support32Bit = true;