{ lib
, stdenv
, fetchFromGitHub
, cmake
, darwin # Accelerate
, llvmPackages # openmp
, withMkl ? false, mkl
, withCUDA ? false
, withCuDNN ? false
, cudaPackages
# Enabling both withOneDNN and withOpenblas is broken
# https://github.com/OpenNMT/CTranslate2/issues/1294
, withOneDNN ? false, oneDNN
, withOpenblas ? true, openblas
, withRuy ? true

# passthru tests
, libretranslate
, wyoming-faster-whisper
}:

let
  cmakeBool = b: if b then "ON" else "OFF";
in
stdenv.mkDerivation rec {
  pname = "ctranslate2";
  version = "4.2.1";

  src = fetchFromGitHub {
    owner = "OpenNMT";
    repo = "CTranslate2";
    rev = "v${version}";
    hash = "sha256-Bg25HL7BDM+SHtM0m7mJ3mAdpFe4kefdiDx5Ek1pQBs=";
    fetchSubmodules = true;
  };

  nativeBuildInputs = [
    cmake
  ] ++ lib.optionals withCUDA [
    cudaPackages.cuda_nvcc
  ];

  cmakeFlags = [
    # https://opennmt.net/CTranslate2/installation.html#build-options
    # https://github.com/OpenNMT/CTranslate2/blob/54810350e662ebdb01ecbf8e4a746f02aeff1dd7/python/tools/prepare_build_environment_linux.sh#L53
    # https://github.com/OpenNMT/CTranslate2/blob/59d223abcc7e636c1c2956e62482bc3299cc7766/python/tools/prepare_build_environment_macos.sh#L12
    "-DOPENMP_RUNTIME=COMP"
    "-DWITH_CUDA=${cmakeBool withCUDA}"
    "-DWITH_CUDNN=${cmakeBool withCuDNN}"
    "-DWITH_DNNL=${cmakeBool withOneDNN}"
    "-DWITH_OPENBLAS=${cmakeBool withOpenblas}"
    "-DWITH_RUY=${cmakeBool withRuy}"
    "-DWITH_MKL=${cmakeBool withMkl}"
  ]
  ++ lib.optional stdenv.isDarwin "-DWITH_ACCELERATE=ON";

  buildInputs = lib.optionals withMkl [
    mkl
  ] ++ lib.optionals withCUDA [
    cudaPackages.cuda_cccl # <nv/target> required by the fp16 headers in cudart
    cudaPackages.cuda_cudart
    cudaPackages.libcublas
    cudaPackages.libcurand
  ] ++ lib.optionals (withCUDA && withCuDNN) [
    cudaPackages.cudnn
  ] ++ lib.optionals withOneDNN [
    oneDNN
  ] ++ lib.optionals withOpenblas [
    openblas
  ] ++ lib.optionals stdenv.isDarwin [
    llvmPackages.openmp
    darwin.apple_sdk.frameworks.Accelerate
  ] ++ lib.optionals (stdenv.isDarwin && stdenv.isx86_64) [
    darwin.apple_sdk.frameworks.CoreGraphics
    darwin.apple_sdk.frameworks.CoreVideo
  ];

  passthru.tests = {
    inherit
      libretranslate
      wyoming-faster-whisper
    ;
  };

  meta = with lib; {
    description = "Fast inference engine for Transformer models";
    mainProgram = "ct2-translator";
    homepage = "https://github.com/OpenNMT/CTranslate2";
    changelog = "https://github.com/OpenNMT/CTranslate2/blob/${src.rev}/CHANGELOG.md";
    license = licenses.mit;
    maintainers = with maintainers; [ hexa misuzu ];
    broken =
      (lib.versionOlder cudaPackages.cudaVersion "11.4")
      || !(withCuDNN -> withCUDA);
  };
}