defmodule Beaver.MixProject do
  use Mix.Project

  def project do
    [
      app: :beaver,
      version: "0.2.13",
      elixir: "~> 1.13",
      start_permanent: Mix.env() == :prod,
      elixirc_paths: elixirc_paths(Mix.env()),
      deps: deps(),
      description: description(),
      docs: docs(),
      package: package(),
      compilers: [:cmake] ++ Mix.compilers(),
      aliases: aliases()
    ]
  end

  defp description() do
    "Beaver, a MLIR Toolkit in Elixir"
  end

  defp docs() do
    [
      main: "Beaver",
      extras: [
        "guides/introducing-beaver.md",
        "guides/your-first-beaver-compiler.livemd"
      ],
      filter_modules: fn m, _meta ->
        name = Atom.to_string(m)

        not (String.contains?(name, "Beaver.MLIR.Dialect.") ||
               String.contains?(name, "Beaver.MLIR.CAPI."))
      end,
      api_reference: false,
      groups_for_modules: [
        DSL: [
          Beaver,
          ~r"Beaver.DSL.*",
          ~r"Beaver.Walker.*"
        ],
        MLIR: [
          ~r"Beaver.MLIR.*"
        ],
        Native: [
          ~r"Beaver.Native.*"
        ]
      ]
    ]
  end

  defp package() do
    [
      licenses: ["Apache-2.0", "MIT"],
      links: %{"GitHub" => "https://github.com/beaver-project/beaver"},
      files: ~w{
        lib .formatter.exs mix.exs README*
        native/mlir-zig/src/*.zig
        native/mlir-zig/prod/build.zig
        native/mlir-zig/dev/build.zig
        native/mlir-zig/test/build.zig
        native/**/CMakeLists.txt
        native/**/*.cmake
        native/**/*.h
        native/**/*.td
        native/**/*.cpp
        checksum-*.exs
      }
    ]
  end

  def application do
    [
      mod: {Beaver.Application, []},
      start_phases: [load_dialect_modules: []],
      extra_applications: [:logger]
    ]
  end

  defp elixirc_paths(:test), do: ["lib", "test/support"]
  defp elixirc_paths(_), do: ["lib"]

  defp deps do
    [
      {:kinda, "~> 0.2.2"},
      {:ex_doc, ">= 0.0.0", only: :dev, runtime: false}
    ]
  end

  defp aliases do
    ["compile.cmake": &cmake/1]
  end

  defmodule LLVM.Config do
    defp llvm_config_from_sys_env() do
      System.get_env("LLVM_CONFIG_PATH")
    end

    defp run_llvm_config(sub_cmd) do
      llvm_config = llvm_config_from_sys_env()

      if llvm_config do
        with {path, 0} <- System.cmd(llvm_config, [sub_cmd]) do
          {:ok, String.trim(path)}
        else
          _ ->
            {:error, "failed to run llvm-config"}
        end
      else
        {:error, "LLVM_CONFIG_PATH is not set"}
      end
    end

    def include_dir() do
      run_llvm_config("--includedir")
    end

    def lib_dir() do
      run_llvm_config("--libdir")
    end
  end

  require Logger

  defp do_cmake() do
    cmake_project = "native/mlir-c"
    build = Path.join(Mix.Project.app_path(), "mlir-c-build")
    install = Path.join(Mix.Project.app_path(), "native-install")

    Logger.debug("[CMake] configuring...")

    {:ok, llvm_lib_dir} = LLVM.Config.lib_dir()

    llvm_cmake_dir = Path.join(llvm_lib_dir, "cmake/llvm")
    mlir_cmake_dir = Path.join(llvm_lib_dir, "cmake/mlir")

    {_, 0} =
      System.cmd(
        "cmake",
        [
          "-S",
          cmake_project,
          "-B",
          build,
          "-G",
          "Ninja",
          "-DLLVM_DIR=#{llvm_cmake_dir}",
          "-DMLIR_DIR=#{mlir_cmake_dir}",
          "-DCMAKE_INSTALL_PREFIX=#{install}"
        ],
        stderr_to_stdout: true
      )

    Logger.debug("[CMake] building...")

    with {_, 0} <- System.cmd("cmake", ["--build", build, "--target", "install"]) do
      Logger.debug("[CMake] installed to #{install}")
      :ok
    else
      {error, _} ->
        Logger.error(error)
        {:error, [error]}
    end
  end

  @build_cmake Application.compile_env(:beaver, :build_cmake, false)
  defp cmake(args) do
    if @build_cmake or "--force" in args do
      do_cmake()
    else
      :noop
    end
  end
end