messenger_bot

defmodule MessengerBot.Service.MessengerProfile do
  @moduledoc """
  Facebook Messenger 'Message' API
  """

  alias MessengerBot.Client
  alias MessengerBot.Config
  alias MessengerBot.Payload.{MessengerProfileSetRequest,
    MessengerProfileSetResponse, MessengerProfileReadResponse}

  @path "/messenger_profile"

  @doc """
  Setup get_started_button
  """
  @spec setup_get_started_button(String.t, MessengerProfileSetRequest.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  def setup_get_started_button(page_id,
    %MessengerProfileSetRequest{get_started: get_started} = request)
    when not is_nil(get_started) do
    save(page_id, request)
  end

  @doc """
  Read get_started_button
  """
  @spec read_get_started_button(String.t) ::
    MessengerProfileReadResponse.t | {:error, Map.t}
  def read_get_started_button(page_id) do
    read(page_id, "get_started")
  end

  @doc """
  Delete get_started_button
  """
  @spec delete_get_started_button(String.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  def delete_get_started_button(page_id) do
    request = %{fields: ["get_started"]}
    delete(page_id, request)
  end

  @doc """
  Setup persistent menu
  """
  @spec setup_persistent_menu(String.t, MessengerProfileSetRequest.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  def setup_persistent_menu(page_id,
    %MessengerProfileSetRequest{persistent_menu: persistent_menu} = request)
    when not is_nil(persistent_menu) do
    save(page_id, request)
  end

  @doc """
  Read persistent menu
  """
  @spec read_persistent_menu(String.t) ::
    MessengerProfileReadResponse.t | {:error, Map.t}
  def read_persistent_menu(page_id) do
    read(page_id, "persistent_menu")
  end

  @doc """
  Delete persistent menu
  """
  @spec delete_persistent_menu(String.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  def delete_persistent_menu(page_id) do
    request = %{fields: ["persistent_menu"]}
    delete(page_id, request)
  end

  @doc """
  Setup white listed domains
  """
  @spec setup_whitelisted_domains(String.t, MessengerProfileSetRequest.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  def setup_whitelisted_domains(page_id, %MessengerProfileSetRequest{
    whitelisted_domains: whitelisted_domains} = request)
    when not is_nil(whitelisted_domains) do
    save(page_id, request)
  end

  @doc """
  White listed domains
  """
  @spec whitelisted_domains(String.t) ::
    MessengerProfileReadResponse.t | {:error, Map.t}
  def whitelisted_domains(page_id) do
    read(page_id, "whitelisted_domains")
  end

  @spec save(String.t, MessengerProfileSetRequest.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  defp save(page_id, %MessengerProfileSetRequest{} = request) do
    page_token = Config.page_token(page_id)
    case Client.post(Client.url(@path, page_token), request) do
      %HTTPoison.Response{} = response ->
        attrs = :jiffy.decode(response.body, [:return_maps])
        %MessengerProfileSetResponse{result: attrs["result"]}
      {:error, err} ->
        {:error, %{details: err}}
    end
  end

  @spec read(String.t, String.t) ::
    MessengerProfileReadResponse.t | {:error, Map.t}
  defp read(page_id, fields) do
    page_token = Config.page_token(page_id)
    url = Client.url(@path, page_token) <> "&fields=#{fields}"
    case Client.get(url) do
      %HTTPoison.Response{} = response ->
        attrs = :jiffy.decode(response.body, [:return_maps])
        %MessengerProfileReadResponse{data: attrs["data"]}
      {:error, err} ->
        {:error, %{details: err}}
    end
  end

  @spec delete(String.t, Map.t) ::
    MessengerProfileSetResponse.t | {:error, Map.t}
  defp delete(page_id, request) do
    page_token = Config.page_token(page_id)
    case Client.delete(Client.url(@path, page_token), request) do
      %HTTPoison.Response{} = response ->
        attrs = :jiffy.decode(response.body, [:return_maps])
        %MessengerProfileSetResponse{result: attrs["result"]}
      {:error, err} ->
        {:error, %{details: err}}
    end
  end
end