1 files changed, 6 insertions, 94 deletions
diff --git a/pkgs/games/itch/towerfall-ascension.nix b/pkgs/games/itch/towerfall-ascension.nix
index a4ba5abf..21704211 100644
--- a/pkgs/games/itch/towerfall-ascension.nix
+++ b/pkgs/games/itch/towerfall-ascension.nix
@@ -1,94 +1,11 @@
 { stdenv, lib, buildGame, fetchItch, makeWrapper, p7zip, unzip, mono50
-, SDL2, SDL2_image, libGL, libvorbis, openal
-
-, writeScriptBin, coreutils
-, fetchNuGet, writeText
+, SDL2, SDL2_image, libGL, libvorbis, openal, monogamePatcher, writeScriptBin
+, coreutils
 
 , darkWorldExpansion ? true
 }:
 
-let
-  cecil = fetchNuGet {
-    baseName = "Mono.Cecil";
-    version = "0.10-beta7";
-    sha256 = "03bina3llcnylrfrvp5psnwrfn757j7zch5r360rpdn7gmcjjcpl";
-    outputFiles = [ "lib/net40/*" ];
-  };
-
-  # We need to patch a few occurences of System.IO.FileStream which are used
-  # with the default arguments for FileAccess. The defaults open the file in
-  # read-write mode and given that all the game data files are in the read-only
-  # Nix store, we'd get an UnauthorizedAccessException.
-  patcher = writeText "patcher.cs" ''
-    using System.Linq;
-    using System.Collections.Generic;
-    using Mono.Cecil;
-    using Mono.Cecil.Cil;
-    using Mono.Cecil.Rocks;
-
-    public class patcher {
-      private ModuleDefinition module;
-
-      private patcher(List<string> typesToPatch) {
-        this.module = ModuleDefinition.ReadModule("TowerFall.exe");
-
-        var filtered = this.module.Types
-          .Where(p => typesToPatch.Contains(p.Name));
-
-        foreach (var toPatch in filtered) {
-          patch_class(toPatch);
-        }
-
-        this.module.Write("TowerFallPatched.exe");
-      }
-
-      private void patch_method(MethodDefinition md) {
-        var il = md.Body.GetILProcessor();
-
-        var fileStreams = md.Body.Instructions
-          .Where(i => i.OpCode == OpCodes.Newobj)
-          .Where(i => (i.Operand as MethodReference).DeclaringType
-                      .FullName == "System.IO.FileStream");
-
-        foreach (Instruction i in fileStreams.ToList()) {
-          var fileAccessRead = il.Create(OpCodes.Ldc_I4_1);
-          il.InsertBefore(i, fileAccessRead);
-
-          var ctorType = this.module.AssemblyReferences.Select(
-            x => new {
-              type = this.module.AssemblyResolver.Resolve(x)
-                .MainModule.GetType("System.IO.FileStream")
-            }
-          ).Where(x => x.type != null).Select(x => x.type).First();
-
-          string wantedCtor = "System.Void System.IO.FileStream"
-                            + "::.ctor(System.String,"
-                            + "System.IO.FileMode,"
-                            + "System.IO.FileAccess)";
-
-          var newCtor = ctorType.GetConstructors()
-            .Single(x => x.ToString() == wantedCtor);
-
-          var refCtor = this.module.ImportReference(newCtor);
-          il.Replace(i, il.Create(OpCodes.Newobj, refCtor));
-        }
-      }
-
-      private void patch_class(TypeDefinition td) {
-        foreach (var nested in td.NestedTypes) patch_class(nested);
-        foreach (MethodDefinition md in td.Methods) patch_method(md);
-      }
-
-      public static void Main() {
-        var typesToPatch = new List<string>() {
-          "Texture", "IntroScene", "SFX", "SFXVaried"
-        };
-        new patcher(typesToPatch);
-      }
-    }
-  '';
-
-in buildGame rec {
+buildGame rec {
   name = "towerfall-ascension-${version}";
   version = "20160723";
 
@@ -113,16 +30,11 @@ in buildGame rec {
   '';
 
   patchPhase = ''
-    { export MONO_PATH=${cecil}/lib/dotnet/Mono.Cecil
-      mcs ${lib.escapeShellArg patcher} -out:patcher \
-        -lib:${cecil}/lib/dotnet/Mono.Cecil \
-        -r:Mono.Cecil -r:Mono.Cecil.Rocks
-      mono patcher
-      mv TowerFallPatched.exe TowerFall.exe
-    }
+    monogame-patcher fix-filestreams -i TowerFall.exe \
+      Texture IntroScene SFX SFXVaried
   '';
 
-  nativeBuildInputs = [ makeWrapper mono50 ];
+  nativeBuildInputs = [ makeWrapper mono50 monogamePatcher ];
 
   libdir = if stdenv.system == "x86_64-linux" then "lib64" else "lib";