import "dart:io";
import "package:hooks/hooks.dart";
import "package:code_assets/code_assets.dart";

Future<void> main(List<String> args) => build(args, (input, output) async {
  final buildDir = input.packageRoot.resolve("src/");
  if (await File(buildDir.resolve("lock").toFilePath()).exists()) return;

  final codeConfig = input.config.code;
  final targetOS = codeConfig.targetOS;
  final targetArch = codeConfig.targetArchitecture;

  String libFileName;
  Map<String, String> env = {};
  switch (targetOS) {
    case OS.linux:
      libFileName = "libgomuks.so";
      break;
    case OS.macOS:
      libFileName = "libgomuks.dylib";
      break;
    case OS.windows:
      libFileName = "libgomuks.dll";
      break;
    case OS.android:
      libFileName = "libgomuks.so";

      final targetNdkApi = codeConfig.android.targetNdkApi;

      final ndkHome = Platform.environment["ANDROID_NDK_HOME"]
          ?? Platform.environment["ANDROID_NDK_ROOT"]
          ?? Platform.environment["NDK_HOME"]
          ?? await _findNdkFromSdk();
      if (ndkHome == null) {
        throw Exception(
          "Could not find Android NDK. Set ANDROID_NDK_HOME or install via sdkmanager.",
        );
      }

      final hostTag = _ndkHostTag();
      final (goArch, ccTriple) = _androidArch(targetArch);
      final cc = "$ndkHome/toolchains/llvm/prebuilt/$hostTag/bin/$ccTriple$targetNdkApi-clang";

      env = {
        "CGO_ENABLED": "1",
        "GOOS": "android",
        "GOARCH": goArch,
        "CC": cc,
      };
      break;
    default:
      throw UnsupportedError("Unsupported OS: $targetOS");
  }

  final gomuksBuildDir = buildDir.resolve("gomuks/");
  final libFile = gomuksBuildDir.resolve("${targetArch.name}/$libFileName");

  // goheif/dav1d supported on Android would need to fix upstream
  final tags = targetOS == OS.android ? "goolm,noheic" : "goolm";

  print("Building Gomuks shared library $libFileName (${targetOS.name}/${targetArch.name}) from source...");
  final result = await Process.run("go", [
    "build",
    "-tags", tags,
    "-o",
    libFile.path,
    "-buildmode=c-shared",
  ], workingDirectory: gomuksBuildDir.resolve("source/pkg/ffi/").toFilePath(),
     environment: env.isNotEmpty ? env : null);

  if (result.exitCode != 0) {
    throw Exception("Failed to build Gomuks shared library\n${result.stderr}");
  }

  final generatedFile = "src/third_party/gomuks.g.dart";
  print("Adding $libFileName as asset...");
  output
    ..assets.code.add(
      CodeAsset(
        package: "nexus",
        name: generatedFile,
        linkMode: DynamicLoadingBundled(),
        file: libFile,
      ),
    )
    ..dependencies.add(libFile)
    ..dependencies.add(gomuksBuildDir);
  print("Done!");
});

Future<String?> _findNdkFromSdk() async {
  // pretty sure this wont be needed with nix, i'll get this removed
  final androidHome = Platform.environment["ANDROID_HOME"]
      ?? Platform.environment["ANDROID_SDK_ROOT"];
  if (androidHome == null) return null;
  final ndkDir = Directory("$androidHome/ndk");
  if (!await ndkDir.exists()) return null;
  final versions = await ndkDir.list().toList();
  if (versions.isEmpty) return null;
  versions.sort((a, b) => a.path.compareTo(b.path));
  return versions.last.path;
}

String _ndkHostTag() {
  if (Platform.isMacOS) {
    return "darwin-x86_64";
  } else if (Platform.isLinux) {
    return "linux-x86_64";
  } else if (Platform.isWindows) {
    return "windows-x86_64";
  }
  throw UnsupportedError("Unsupported host platform for Android NDK");
}

(String goArch, String ccTriple) _androidArch(Architecture arch) {
  switch (arch) {
    case Architecture.arm64:
      return ("arm64", "aarch64-linux-android");
    case Architecture.arm:
      return ("arm", "armv7a-linux-androideabi");
    case Architecture.x64:
      return ("amd64", "x86_64-linux-android");
    case Architecture.ia32:
      return ("386", "i686-linux-android");
    default:
      throw UnsupportedError("Unsupported Android architecture: $arch");
  }
}