From 801cc447659ee28e15b521f08e84df9c3d5f1bb6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B8rn=20Forsman?= <bjorn.forsman@gmail.com>
Date: Wed, 19 Jul 2023 13:11:14 +0200
Subject: [PATCH 1/3] retroarch: add support for declarative settings

Add a new optional 'settings' attrset to the wrapper derivation, which
gets serialized to a file and passed to RetroArch as --appendconfig= at
runtime. This allows overriding settings from
~/.config/retroarch/retroarch.cfg (which initially gets created as a
dump of all internal retroarch settings -- stateful and messy).
---
 .../emulators/retroarch/wrapper.nix            | 18 +++++++++++++++---
 pkgs/top-level/all-packages.nix                |  4 ++--
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/pkgs/applications/emulators/retroarch/wrapper.nix b/pkgs/applications/emulators/retroarch/wrapper.nix
index afef0bef8a48..4698bbe5bbed 100644
--- a/pkgs/applications/emulators/retroarch/wrapper.nix
+++ b/pkgs/applications/emulators/retroarch/wrapper.nix
@@ -3,16 +3,28 @@
 , makeWrapper
 , retroarch
 , symlinkJoin
+, runCommand
 , cores ? [ ]
+, settings ? { }
 }:
 
 let
+  settingsPath = runCommand "declarative-retroarch.cfg"
+    {
+      value = lib.concatStringsSep "\n" (lib.mapAttrsToList (n: v: "${n} = \"${v}\"") settings);
+      passAsFile = [ "value" ];
+    }
+    ''
+      cp "$valuePath" "$out"
+    '';
+
   # All cores should be located in the same path after symlinkJoin,
   # but let's be safe here
   coresPath = lib.lists.unique (map (c: c.libretroCore) cores);
-  wrapperArgs = lib.strings.escapeShellArgs
-    (lib.lists.flatten
-      (map (p: [ "--add-flags" "-L ${placeholder "out" + p}" ]) coresPath));
+  wrapperArgs = lib.strings.escapeShellArgs (
+    (lib.lists.flatten (map (p: [ "--add-flags" "-L ${placeholder "out" + p}" ]) coresPath))
+    ++ [ "--add-flags" "--appendconfig=${settingsPath}" ]
+  );
 in
 symlinkJoin {
   name = "retroarch-with-cores-${lib.getVersion retroarch}";
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index cf4fcc344741..786c227cd7de 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2642,9 +2642,9 @@ with pkgs;
       (builtins.attrValues libretro);
   };
 
-  wrapRetroArch = { retroarch }:
+  wrapRetroArch = { retroarch, settings ? {} }:
     callPackage ../applications/emulators/retroarch/wrapper.nix
-      { inherit retroarch; };
+      { inherit retroarch settings; };
 
   retroarch = wrapRetroArch {
     retroarch = retroarchBare.override {

From 35c3c81655802b4d039754e0b2ba0248583e11b3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B8rn=20Forsman?= <bjorn.forsman@gmail.com>
Date: Wed, 19 Jul 2023 13:29:45 +0200
Subject: [PATCH 2/3] retroarch-joypad-autoconfig: init at 1.15.0

https://github.com/libretro/retroarch-joypad-autoconfig

(In preparation for making joypads work out-of-the-box in RetroArch.)
---
 .../retroarch/retroarch-joypad-autoconfig.nix | 28 +++++++++++++++++++
 pkgs/top-level/all-packages.nix               |  2 ++
 2 files changed, 30 insertions(+)
 create mode 100644 pkgs/applications/emulators/retroarch/retroarch-joypad-autoconfig.nix

diff --git a/pkgs/applications/emulators/retroarch/retroarch-joypad-autoconfig.nix b/pkgs/applications/emulators/retroarch/retroarch-joypad-autoconfig.nix
new file mode 100644
index 000000000000..92ba7f20c8b3
--- /dev/null
+++ b/pkgs/applications/emulators/retroarch/retroarch-joypad-autoconfig.nix
@@ -0,0 +1,28 @@
+{ lib
+, stdenvNoCC
+, fetchFromGitHub
+}:
+
+stdenvNoCC.mkDerivation rec {
+  pname = "retroarch-joypad-autoconfig";
+  version = "1.15.0";
+
+  src = fetchFromGitHub {
+    owner = "libretro";
+    repo = "retroarch-joypad-autoconfig";
+    rev = "v${version}";
+    hash = "sha256-/F2Y08uDA/pIIeLiLfOQfGVjX2pkuOqPourlx2RbZ28=";
+  };
+
+  makeFlags = [
+    "PREFIX=$(out)"
+  ];
+
+  meta = with lib; {
+    description = "Joypad autoconfig files";
+    homepage = "https://www.libretro.com/";
+    license = licenses.mit;
+    maintainers = with maintainers; teams.libretro.members ++ [ ];
+    platforms = platforms.all;
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 786c227cd7de..70beb3e102f3 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2655,6 +2655,8 @@ with pkgs;
 
   retroarch-assets = callPackage ../applications/emulators/retroarch/retroarch-assets.nix { };
 
+  retroarch-joypad-autoconfig = callPackage ../applications/emulators/retroarch/retroarch-joypad-autoconfig.nix { };
+
   libretranslate = with python3.pkgs; toPythonApplication libretranslate;
 
   libretro = recurseIntoAttrs

From 9d793505b9e2b5d58f50e60ebfa74d7bd0665cc4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B8rn=20Forsman?= <bjorn.forsman@gmail.com>
Date: Wed, 19 Jul 2023 14:01:25 +0200
Subject: [PATCH 3/3] retroarch: auto-detect joypads

Set the 'joypad_autoconfig_dir' setting to where autoconfig files are,
instead of using the built-in default of ~/.config/retroarch/autoconfig,
which is empty.

Tested with my PS5 DualSense controller, which now works.
---
 pkgs/top-level/all-packages.nix | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 70beb3e102f3..74188daa63d8 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2651,6 +2651,9 @@ with pkgs;
       withAssets = true;
       withCoreInfo = true;
     };
+    settings = {
+      joypad_autoconfig_dir = "${retroarch-joypad-autoconfig}/share/libretro/autoconfig";
+    };
   };
 
   retroarch-assets = callPackage ../applications/emulators/retroarch/retroarch-assets.nix { };