feat(nix): refactor Flake and Migrate Android Support (#1280)

flake.nix

@@ -10,47 +10,101 @@
     };
   };
 
-  outputs = { self, nixpkgs, flake-utils, rust-overlay, ... }:
-    flake-utils.lib.eachDefaultSystem (system:
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+      rust-overlay,
+      ...
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
       let
         overlays = [ (import rust-overlay) ];
         pkgs = import nixpkgs {
           inherit system overlays;
+          config = {
+            licenseAccepted = true;
+            allowUnfree = true;
+          };
         };
         rustVersion = "1.89.0";
-        rust = pkgs.rust-bin.stable.${rustVersion}.default.override{
-          extensions = [ "rust-src" "rust-analyzer" ];
+        makeRust =
+          features:
+          pkgs.rust-bin.stable.${rustVersion}.default.override {
+            extensions = [
+              "rust-src"
+              "rust-analyzer"
+            ]
+            ++ (if builtins.elem "android" features then android.rust.extensions else [ ]);
+
+            targets = if builtins.elem "android" features then android.rust.targets else [ ];
+          };
+
+        android = import ./android.nix {
+          inherit pkgs system nixpkgs;
         };
+
+        makeShell =
+          features:
+          let
+            hasFeature = feature: builtins.elem feature features;
+            withFeature = feature: pkgList: if hasFeature feature then pkgList else [ ];
+            flattenPaths = xs: builtins.concatLists (map (p: if builtins.isList p then p else [ p ]) xs);
+            rust = makeRust features;
+          in
+          pkgs.mkShell (rec {
+            nativeBuildInputs =
+              with pkgs;
+              (
+                [
+                  rust
+                  protobuf
+                  clang
+                  pkg-config
+                  bridge-utils # for three node test
+                ]
+                ++ (withFeature "web" [
+                  nodejs_22
+                  pnpm
+                ])
+                ++ (withFeature "android" android.packages)
+              );
+
+            buildInputs = with pkgs; ([
+              zstd
+              openssl
+              libclang
+              llvmPackages.libclang
+              libsoup_3
+              webkitgtk_4_1
+            ]);
+
+            RUST_SRC_PATH = "${rust}/lib/rustlib/src/rust/library";
+            LIBCLANG_PATH = "${pkgs.libclang.lib}/lib";
+            BINDGEN_EXTRA_CLANG_ARGS = "-I${pkgs.clang}/resource-root/include";
+            LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath (flattenPaths (buildInputs ++ nativeBuildInputs));
+            ZSTD_SYS_USE_PKG_CONFIG = true;
+            KCP_SYS_EXTRA_HEADER_PATH = "${pkgs.libclang.lib}/lib/clang/19/include:${pkgs.glibc.dev}/include";
+          }
+          // (if hasFeature "android" then android.envVars else { }));
       in
       {
-        devShells.default = pkgs.mkShell rec {
-          nativeBuildInputs = with pkgs; [
-            rust
-            protobuf
-            clang
-            pkg-config
-
-            # web
-            nodejs_22
-            pnpm
+        devShells = {
+          default = makeShell [ ];
+          core = makeShell [ ];
+          web = makeShell [ "web" ];
+          gui = makeShell [ "gui" ];
+          android = makeShell [
+            "android"
+            "web"
           ];
-          buildInputs = with pkgs; [
-            zstd
-            openssl
-            libclang
-            llvmPackages.libclang
-
-            # gui
-            webkitgtk_4_1
-            libsoup_3
+          full = makeShell [
+            "web"
+            "gui"
+            "android"
           ];
-
-          RUST_SRC_PATH = "${rust}/lib/rustlib/src/rust/library";
-          LIBCLANG_PATH = "${pkgs.libclang.lib}/lib";
-          BINDGEN_EXTRA_CLANG_ARGS = "-I${pkgs.clang}/resource-root/include";
-          LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath (buildInputs ++ nativeBuildInputs);
-          ZSTD_SYS_USE_PKG_CONFIG = true;
-          KCP_SYS_EXTRA_HEADER_PATH = "${pkgs.libclang.lib}/lib/clang/19/include:${pkgs.glibc.dev}/include";
         };
       }
     );