defmodule Pleroma.Web.ActivityPub.MRF.StealEmojiPolicy do
  require Logger
  @moduledoc "Detect new emoji and steal them"
  @behaviour Pleroma.Web.ActivityPub.MRF

  defp has_emojo(installed_emoji, str) do
    result = for emojo <- installed_emoji, elem(emojo, 0) == str, do: true
    length(result) == 1
  end

  @impl true
  def filter(%{"object" => %{"emoji" => foreign_emoji}} = object) do
    num_foreign_emoji = Kernel.map_size(foreign_emoji)

    if num_foreign_emoji > 0 do
      Logger.debug("#{num_foreign_emoji} EMOJI TO PROCESS")
      installed_emoji = Pleroma.Emoji.get_all()

      new_files =
        for {emojo_shortcode, emojo_url} <- foreign_emoji,
            !has_emojo(installed_emoji, emojo_shortcode) do
          Logger.debug("HANDLING EMOJO")
          
          remote_emojo = HTTPoison.get!(emojo_url)
          with {:ok, current_dir} <- File.cwd() do
            new_file = current_dir <> "/priv/static/emoji/stolen/" <> emojo_shortcode <> Path.extname(emojo_url)

            {:ok, file} = File.open(new_file, [:write])
            IO.binwrite(file, remote_emojo.body)
            File.close(file)
            Logger.debug("SAVED EMOJO")
            new_file
          end
        end

      Logger.debug("EMOJI FILES: #{inspect(new_files)}")

      if length(new_files) > 0 do
        Logger.debug("RELOADING EMOJI")
        Pleroma.Emoji.reload()
      else
        Logger.debug("NO EMOJI TO LOAD")
      end
    end

    {:ok, object}
  end

  @impl true
  def filter(object) do
    {:ok, object}
  end

  @impl true
  def describe, do: {:ok, %{}}
end