defmodule HahaYes.Utility do
  @moduledoc """
  Various utilities to be reused in commands
  """

  @doc """
  Download utility with the format at 480p by default.

  ## Example

    ```
    iex> HahaYes.Utility.download("https://x.com/i/status/1844841048603783249", "#{System.tmp_dir}/test")

    {:ok, /tmp}/test.mp4
    ```

    ```
    iex> HahaYes.Utility.download("invalid", "#{System.tmp_dir}/test")

    {:error, "[generic] Extracting URL: invalid\\nERROR: [generic] 'invalid' is not a valid URL. Set --default-search "ytsearch" (or run  yt-dlp "ytsearch:invalid" ) to search YouTube"}
    ```
  """

  def download(url, output, format \\ "bestvideo[height<=?480]+bestaudio/best") do
    opt = ["-f", format, url, "-o", "#{output}.%(ext)s", "--force-overwrites", "--playlist-reverse", "--no-playlist", "--remux-video=mp4/webm/mov", "--no-warnings"];

    {error_output, status} = System.cmd("yt-dlp", opt, [stderr_to_stdout: true])
    if status !== 0 do
      {:error, error_output}
    else
      {:ok, Enum.at(Path.wildcard("#{output}.*"), 0)}
    end
  end
end