unreal_engine_bug_flake/flake.nix

{
  description = "Wine minimal configuration to reproduce the problem";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachSystem flake-utils.lib.allSystems (system:
      let
        pkgs = import nixpkgs { inherit system; };

        inherit (pkgs.lib.strings) concatStringsSep;
        inherit (pkgs) writeShellScriptBin fetchurl;

        epic_games_launcher = fetchurl {
          url = "https://launcher-public-service-prod06.ol.epicgames.com/launcher/api/installer/download/EpicGamesLauncherInstaller.msi";
          name = "EpicGamesLauncherInstaller.msi";
          # hash = pkgs.lib.fakeHash;
          hash = "sha256-vbd+h7nWZmNOGC6kJILZVZElyo5iwjmbitLGtCOVqqg=";
        };

        # concat winetricks args
        winetricksPackages = [ "corefonts" ];
        winetricksArgs =
          if (builtins.length winetricksPackages) > 0
          then concatStringsSep " " winetricksPackages
          else "-V";

        # concat dll overrides
        wineDllOverrides = ["winemenubuilder.exe=d"];
        wineDllOverridesEnv = pkgs.lib.strings.concatStringsSep "," wineDllOverrides;

        install_script = writeShellScriptBin "install" ''
          echo "Installing Dependencies"
          winetricks -q -f ${winetricksArgs}
          wineserver -k
          echo "Dependencies Installed"

          echo "Installing Epic Games Launcher"
          $WINE ${epic_games_launcher} /q
          wineserver -k
          echo "Epic Games Launcher Installed"
        '';

        stop_script = writeShellScriptBin "stop" ''
          wineserver -k
        '';

        clean_script = writeShellScriptBin "clean" ''
          wineserver -k
          rm -rf $WINEPREFIX
        '';

        run_script = writeShellScriptBin "run" ''
          $WINE "$WINEPREFIX/drive_c/Program Files (x86)/Epic Games/Launcher/Portal/Binaries/Win32/EpicGamesLauncher.exe"
          wineserver -w
        '';
      in
      {
        devShells = {
          default = pkgs.mkShell {
            packages = with pkgs; [
              # Wine packages
              wineWowPackages.unstableFull
              winetricks

              # Custom scripts
              install_script
              run_script
              stop_script
              clean_script
            ];

            shellHook = ''
              export WINETRICKS_LATEST_VERSION_CHECK=disabled
              export WINEPREFIX=$(pwd)/wine_prefix
              export WINE=wine
              export WINEARCH="win64"
              export WINEDEBUG=-all
              export WINEDLLOVERRIDES="${wineDllOverridesEnv}"

              if [ ! -d "$WINEPREFIX" ]; then
                install
              fi
            '';
          };
        };
      });
}