defmodule Rclex do
  @on_load :load_nifs
  @compile {:autoload, false}

  require Logger

  @moduledoc """
  T.B.A
  """

  def load_nifs do
    nif = Application.app_dir(:rclex, "priv/rclex")

    :erlang.load_nif(to_charlist(nif), 0)
  end

  # -----------------------init_nif.c--------------------------

  def rcl_get_zero_initialized_init_options do
    raise "NIF rcl_get_zero_initialized_init_options/0 not implemented"
  end

  def rcl_init_options_init(_a) do
    raise "NIF rcl_init_options_init/1 is not implemented"
  end

  def rcl_init_options_fini(_a) do
    raise "NIF rcl_init_options_fini/1 is not implemented"
  end

  def rcl_get_zero_initialized_context do
    raise "NIF rcl_get_zero_initialized_context/0 not implemented"
  end

  @doc """
      return {:ok,rcl_ret_t}
      arguments...(
          int argc,
          char const * const * argv,
          const rcl_init_options_t * options,
          rcl_context_t * context)
        argc,argvに0,NULLを直接入れる関数
  """
  def rcl_init_with_null(_a, _b) do
    raise "NIF rcl_init_with_null/2 not implemented"
  end

  @doc """
      return {:ok,rcl_ret_t}
      arguments...(
          rcl_context_t)
  """
  def shutdown(_a) do
    raise "NIF rcl_shutdown/1 not implemented"
  end

  # -----------------------node_nif.c--------------------------
  # return {:ok,rcl_node_t}
  def rcl_get_zero_initialized_node do
    raise "NIF rcl_get_zero_initialized_node/0 not implemented"
  end

  # return {:ok,rcl_node_options_t}
  def rcl_node_get_default_options do
    raise "NIF rcl_node_get_default_options/0 not implemented"
  end

  @doc """
      return {:ok,rcl_ret_t}
      argument...(
      rcl_node_t * node,
      const char * name,
      const char * namespace_,
      rcl_context_t * context,
      const rcl_node_options_t * options)
  """
  def rcl_node_init(_a, _b, _c, _d, _e) do
    raise "NIF rcl_node_init/5 not implemented"
  end

  def rcl_node_init_without_namespace(_a, _b, _c, _d) do
    raise "NIF rcl_node_init_without_namespace/4 is not implemented"
  end

  @doc """
      return rcl_ret_t
      argument...rcl_node_t
  """
  def rcl_node_fini(_a) do
    raise "NIF rcl_node_fini/1 not implemented"
  end

  def read_guard_condition(_a) do
    raise "haha"
  end

  @doc """
      return char
  """

  def rcl_node_get_name(_a) do
    raise "NIF rcl_node_get_name/1 not implemented"
  end

  # ------------------------------publisher_nif.c--------------------------
  @doc """
      return rcl_publisher_t
      argument...void
  """
  def rcl_get_zero_initialized_publisher do
    raise "NIF get_zero_initialized_publisher/0 not implemented"
  end

  @doc """
      return rcl_publisher_options_t
      argument...void
  """
  def rcl_publisher_get_default_options do
    raise "rcl_get_zero_initialized_publisher/0 not implemented"
  end

  @doc """
      return const char*
      argument...rcl_publisher_t*
  """
  def rcl_publisher_get_topic_name(_a) do
    raise "rcl_get_zero_initialized_publisher/0 not implemented"
  end

  @doc """
      return rcl_ret_t
      argument...rcl_publisher_t*,rcl_node_t*
  """
  def rcl_publisher_fini(_a, _b) do
    raise "rcl_get_zero_initialized_publisher/0 not implemented"
  end

  @doc """
      return rcl_ret_t
      argument...rcl_publisher_t * publisher,
                  const rcl_node_t * node,
                  const rosidl_message_type_support_t * type_support,
                  const char * topic_name,
                  const rcl_publisher_options_t * options
  """
  def rcl_publisher_init(_a, _b, _c, _d) do
    raise "rcl_publisher_init/4 not implemented"
  end

  @doc """
      return bool
      argument...rcl_publisher_t*
  """
  def rcl_publisher_is_valid(_a) do
    raise "rcl_publisher_is_valid/1 not implemented"
  end

  @doc """
    rcl_ret_t
    rcl_publish(
      const rcl_publisher_t * publisher,
      const void * ros_message,
      rmw_publisher_allocation_t * allocation
    );
  """
  def rcl_publish(_a, _b, _c) do
    raise "rcl_publish/3 is not implemented"
  end

  def create_pub_alloc do
    raise "NIF create_pub_alloc/0 is not implemented"
  end

  # ---------------------------subscription_nif.c--------------------------
  def rcl_subscription_get_default_options do
    raise "NIF rcl_subscription_get_default_options is not implemented"
  end

  def rcl_get_zero_initialized_subscription do
    raise "NIF rcl_subscription_get_default_options is not implemented"
  end

  def create_sub_alloc do
    raise "NIF create_suballoc/0 is not implemented"
  end

  @doc """
    rcl_ret_t
    rcl_subscription_init(
      rcl_subscription_t * subscription,
      const rcl_node_t * node,
      const rosidl_message_type_support_t * type_support,
      const char * topic_name,
      const rcl_subscription_options_t * options
  );
  """
  def rcl_subscription_init(_a, _b, _c, _d) do
    raise "NIF rcl_subscription_init is not implemented"
  end

  @doc """
      return rcl_ret_t
      argument...rcl_subscription_t*,rcl_node_t*
  """
  def rcl_subscription_fini(_a, _b) do
    raise "NIF rcl_subscription_fini is not implemented"
  end

  def rcl_subscription_get_topic_name(_a) do
    raise "NIF rcl_subscription_get_topic_name/1 is not implemented"
  end

  @doc """
    rcl_ret_t
    rcl_take(
      const rcl_subscription_t * subscription,
      void * ros_message,
      rmw_message_info_t * message_info,
      rmw_subscription_allocation_t * allocation
    );
  """
  def rcl_take(_a, _b, _c, _d) do
    raise "NIF rcl_take is not implemented"
  end

  # -----------------------------graph_nif.c------------------------------
  @doc """
    rcl_ret_t
    rcl_get_topic_names_and_types(
      const rcl_node_t * node,
      rcl_allocator_t * allocator,
      bool no_demangle,
      rcl_names_and_types_t * topic_names_and_types);
  """
  def rcl_get_topic_names_and_types(_a, _b, _c) do
    raise "NIF rcl_get_topic_names_and_types is not implemented"
  end

  # -----------------------------msg_int16.c------------------------------
  def create_empty_int16 do
    raise "NIF create_empty_int16/0 is not implemented"
  end

  def create_msginfo do
    raise "NIF create_msginfo/0 is not implemented"
  end

  def int16_init(_a) do
    raise "NIF std_msgs__msg__Int16__init/0 not implemented"
  end

  def int16_destroy(_a) do
    raise "NIF std_msgs__msg__Int16__destroy/1 not implemented"
  end

  def get_message_type_from_std_msgs_msg_int16 do
    raise "NIF get_message_type_from_std_msgs_msg_Int16/0 not implemented"
  end

  def readdata_int16(_a) do
    raise "NIF readdata_int16/1 is not implemented"
  end

  def setdata_int16(_a, _b) do
    raise "NIF setdata_int16/2 is not implemented"
  end

  # -----------------------msg_string_nif.c-----------------------------

  def create_empty_string do
    raise "NIF create_empty_string/0 is not implemented"
  end

  def string_init(_a) do
    raise "NIF string_init/1 is not implemented"
  end

  # arg..(initialized msg,string)
  def setdata_string(_a, _b, _c) do
    raise "NIF setdata_string/3 is not implemented"
  end

  # -----------------------------wait_nif.c------------------------------
  def rcl_get_default_allocator do
    raise "NIF rcl_get_default_allocator/0 is not implemented"
  end

  def rcl_get_zero_initialized_wait_set do
    raise "NIF rcl_get_zero_initialized_wait_set/0 is not implemented"
  end

  def rcl_wait_set_init(_a, _b, _c, _d, _e, _f, _g, _h, _i) do
    raise "NIF rcl_wait_set_init/9 is not implemented"
  end

  def rcl_wait_set_fini(_a) do
    raise "NIF rcl_wait_set_fini/1 is not implemented"
  end

  def rcl_wait_set_clear(_a) do
    raise "NIF rcl_wait_set_clear/1 is not implemented"
  end

  def rcl_wait_set_add_subscription(_a, _b) do
    raise "NIF rcl_wait_set_add_subscription/2 is not implemented"
  end

  def rcl_wait(_a, _b) do
    raise "NIF rcl_wait/0 is not implemented"
  end

  def check_subscription(_a) do
    raise "NIF check_subscription/1 is not implemented"
  end

  def check_waitset(_a, _b) do
    raise "NIF check_waitset/2 is not implemented"
  end

  def get_sublist_from_waitset(_a) do
    raise "NIF get_sublist_from_waitset/1 is not implemented"
  end

  # ------------------------ユーザAPI群-------------------
  @doc """
    Rclex初期化
    RCLのコンテキストを有効化
  """
  def rclexinit do
    init_op = rcl_get_zero_initialized_init_options()
    context = rcl_get_zero_initialized_context()
    rcl_init_options_init(init_op)
    rcl_init_with_null(init_op, context)
    rcl_init_options_fini(init_op)
    context
  end

  @doc """
    ノードをひとつだけ作成
    名前空間の有無を設定可能
  """
  def create_singlenode(context, node_name, node_namespace) do
    node = rcl_get_zero_initialized_node()
    node_op = rcl_node_get_default_options()
    rcl_node_init(node, node_name, node_namespace, context, node_op)
    node
  end

  def create_singlenode(context, node_name) do
    node = rcl_get_zero_initialized_node()
    node_op = rcl_node_get_default_options()
    rcl_node_init_without_namespace(node, node_name, context, node_op)
    node
  end

  @doc """
    複数ノード生成
    create_nodes/4ではcreate_nodes/3に加えて名前空間の指定が可能
  """
  def create_nodes(context, node_name, namespace, num_node) do
    node_list =
      Enum.map(0..(num_node - 1), fn n ->
        rcl_node_init(
          rcl_get_zero_initialized_node(),
          node_name ++ Integer.to_charlist(n),
          namespace,
          context,
          rcl_node_get_default_options()
        )
      end)

    node_list
  end

  def create_nodes(context, node_name, num_node) do
    node_list =
      Enum.map(1..num_node, fn n ->
        rcl_node_init_without_namespace(
          rcl_get_zero_initialized_node(),
          node_name ++ Integer.to_charlist(n),
          context,
          rcl_node_get_default_options()
        )
      end)

    node_list
  end

  @doc """
    パブリッシャおよびサブスクライバをひとつだけ生成
  """
  def single_create_publisher(pub_node, topic_name) do
    publisher = rcl_get_zero_initialized_publisher()
    pub_op = rcl_publisher_get_default_options()
    rcl_publisher_init(publisher, pub_node, topic_name, pub_op)
    publisher
  end

  def single_create_subscriber(sub_node, topic_name) do
    subscriber = rcl_get_zero_initialized_subscription()
    sub_op = rcl_subscription_get_default_options()
    rcl_subscription_init(subscriber, sub_node, topic_name, sub_op)
    subscriber
  end

  @doc """
    パブリッシャおよびサブスクライバを複数生成
    :singleもしくは:multiを指定する．
    :single...一つのトピックに複数の出版者または購読者
    :multi...1つのトピックに出版者または購読者1つのペアを複数
  """
  def create_publishers(node_list, topic_name, :single) do
    Enum.map(node_list, fn node ->
      rcl_publisher_init(
        rcl_get_zero_initialized_publisher(),
        node,
        topic_name,
        rcl_publisher_get_default_options()
      )
    end)
  end

  def create_publishers(node_list, topic_name, :multi) do
    Enum.map(0..(length(node_list) - 1), fn index ->
      Rclex.single_create_publisher(
        Enum.at(node_list, index),
        topic_name ++ Integer.to_charlist(index)
      )
    end)
  end

  def create_subscribers(node_list, topic_name, :single) do
    Enum.map(node_list, fn node ->
      rcl_subscription_init(
        rcl_get_zero_initialized_subscription(),
        node,
        topic_name,
        rcl_subscription_get_default_options()
      )
    end)
  end

  def create_subscribers(node_list, topic_name, :multi) do
    Enum.map(0..(length(node_list) - 1), fn index ->
      Rclex.single_create_subscriber(
        Enum.at(node_list, index),
        topic_name ++ Integer.to_charlist(index)
      )
    end)
  end

  @doc """
    ノード間通信に用いるメッセージの初期化
    :int16
  """
  def initialize_msg do
    create_empty_string()
    |> string_init()
  end

  @doc """
    ノード間通信に用いるメッセージの初期化
    :stringであればstring型が使えるようにする(現在使用可能な型)
  """
  def initialize_msgs(msg_count, :string) do
    Enum.map(1..msg_count, fn _ ->
      initialize_msg()
    end)
  end

  # TODO: :int16であればInt16型が使えるようにする(目標)
  def initialize_msgs(msg_count, :int16) do
    Enum.map(1..msg_count, fn _ ->
      create_empty_int16()
    end)
  end

  @doc """
    メッセージにデータをセットする
    現在はstring型のみのサポートになっている
  """
  def setdata(msg, data, :string) do
    data_size = String.length(data)
    setdata_string(msg, String.to_charlist(data), data_size + 1)
  end

  @doc """
    メッセージからstringデータを取得する
  """
  def readdata_string(_a) do
    raise "NIF readdata_string/1 is not implemented"
  end

  @doc """
    ユーザのタスク終了入力を受け付けるAPI.
    0を入力するとchildに渡されたPIDのタスクを終了する
  """
  def waiting_input(sv, child) do
    num =
      IO.gets("")
      |> String.replace("\n", "")
      |> String.to_integer()

    case num do
      0 -> Rclex.Timer.terminate_timer(sv, child)
      _ -> waiting_input(sv, child)
    end
  end

  @doc """
    パブリッシャの終了
  """
  def publisher_finish(pub_list, node_list) do
    Logger.debug("publishers finish")
    n = length(pub_list)

    Enum.map(0..(n - 1), fn index ->
      Rclex.rcl_publisher_fini(Enum.at(pub_list, index), Enum.at(node_list, index))
    end)
  end

  @doc """
    サブスクライバの終了
  """
  def subscriber_finish(sub_list, node_list) do
    Logger.debug("subscribers finish")
    n = length(sub_list)

    Enum.map(0..(n - 1), fn index ->
      Rclex.rcl_subscription_fini(Enum.at(sub_list, index), Enum.at(node_list, index))
    end)
  end

  @doc """
    ノードの終了
    ノード関連のメモリを解放する
  """
  def node_finish(node_list) do
    Logger.debug("node finish")

    Enum.map(node_list, fn node ->
      Rclex.rcl_node_fini(node)
    end)
  end
end