Refactor subprojects in nix flake to be attributes.

Also wrote and by wrote I mean stole from other projects helper
functions for bypassing the nodownload restriction of the nix sandbox.

This uses the wrap files in the repo ecxept for the download part which
has to be an input for reproducibility sake.

The Nix Code is ugly and I am gonna vomit.

flake.nix

@@ -20,6 +20,7 @@
       flake = false;
     };
 
+    # patches only get applied if they follow <subproject_to_patch>-patch naming
     miniaudio-patch = {
       url = "https://wrapdb.mesonbuild.com/v2/miniaudio_0.11.22-2/get_patch";
       flake = false;
@@ -37,16 +38,51 @@
   };
 
   outputs =
-    {
-      self,
-      nixpkgs,
-      flake-utils,
-      ...
-    }@inputs:
+    { self, nixpkgs, flake-utils, ... }@inputs:
     flake-utils.lib.eachDefaultSystem (
       system:
       let
         pkgs = import nixpkgs { inherit system; };
+        lib = pkgs.lib;
+
+        subprojectNames = [
+          "shiggy"
+          "4jlibs"
+          "stb"
+          "simdutf"
+          "miniaudio"
+        ];
+
+        # helper: copy all subproject sources
+        copySubprojects = ''
+          mkdir -p $sourceRoot/subprojects
+          ${lib.concatMapStringsSep "\n" (name: "cp -r ${inputs.${name}} $sourceRoot/subprojects/${name}") subprojectNames}
+          chmod -R u+w $sourceRoot/subprojects
+        '';
+
+        # helper: copy packagefiles
+        copyPackagefiles = ''
+          for proj in ${builtins.toString subprojectNames}; do
+            if [ -d "subprojects/packagefiles/$proj" ]; then
+              cp -r subprojects/packagefiles/$proj/* subprojects/$proj/
+            fi
+          done
+        '';
+
+        # helper: apply patches from '-patch' inputs
+        applyPatches = lib.concatMapStringsSep "\n" (name: ''
+          patch_input="${inputs.${name + "-patch"} or ""}"
+          if [ -n "$patch_input" ]; then
+            unzip "$patch_input" -d ${name}-patch-tmp
+            if [ $(ls -1 ${name}-patch-tmp | wc -l) -eq 1 ] && [ -d ${name}-patch-tmp/* ]; then
+              cp -r ${name}-patch-tmp/*/* subprojects/${name}/
+            else
+              cp -r ${name}-patch-tmp/* subprojects/${name}/
+            fi
+            rm -rf ${name}-patch-tmp
+          fi
+        '') subprojectNames;
+
       in
       {
         packages.default = pkgs.clangStdenv.mkDerivation {
@@ -57,34 +93,21 @@
           dontFixup = true;
           dontUseCmakeConfigure = true;
 
-          # 4jcraft - Meson expects this subprojects structure
+          # Disable fortify to prevent buffer overflow detection
+          hardeningDisable = [ "fortify3" "fortify" ];
+
           postUnpack = ''
-            mkdir -p $sourceRoot/subprojects
-
-            cp -r ${inputs.shiggy} $sourceRoot/subprojects/shiggy
-            cp -r ${inputs."4jlibs"} $sourceRoot/subprojects/4jlibs
-            cp -r ${inputs.stb} $sourceRoot/subprojects/stb
-            cp -r ${inputs.simdutf} $sourceRoot/subprojects/simdutf
-            cp -r ${inputs.miniaudio} $sourceRoot/subprojects/miniaudio
-
-            chmod -R u+w $sourceRoot/subprojects
+            ${copySubprojects}
           '';
 
-          # 4jcraft - `stb` and `simdutf` patches
           postPatch = ''
-            cp subprojects/packagefiles/stb/meson.build subprojects/stb/meson.build
-            cp subprojects/packagefiles/simdutf/meson.build subprojects/simdutf/meson.build
-            cp subprojects/packagefiles/simdutf/meson.options subprojects/simdutf/meson.options
+            # Remove wrap files so Meson doesn't try to download them
+            for proj in ${builtins.toString subprojectNames}; do
+              rm -f subprojects/$proj.wrap
+            done
 
-            unzip ${inputs.miniaudio-patch} -d miniaudio-patch-tmp
-            cp -r miniaudio-patch-tmp/*/. subprojects/miniaudio/
-
-            cat > subprojects/miniaudio.wrap <<EOF
-            [wrap-file]
-            directory = miniaudio
-            [provide]
-            dependency_names = miniaudio
-            EOF
+            ${copyPackagefiles}
+            ${applyPatches}
           '';
 
           nativeBuildInputs = with pkgs; [
@@ -117,7 +140,7 @@
 
           meta = {
             description = "4JCraft";
-            platforms = pkgs.lib.platforms.unix;
+            platforms = lib.platforms.unix;
           };
         };