defmodule Mastomation do
  @moduledoc """
  CLI helpers to fetch and remove Mastodon statuses.
  """

  alias Mastomation.Delete
  alias Mastomation.Parser
  alias Mastomation.Threads

  @doc """
  Parses delete-related CLI options from raw arguments.
  """
  @spec parse([String.t()]) :: map()
  def parse(args \\ []) do
    Delete.parse_options(args)
  end

  @doc """
  Executes the CLI command router.
  """
  @spec run([String.t()]) :: :ok | :error
  def run(args \\ []) do
    parse_args = if args == [], do: ["--help"], else: args
    dispatch(Parser.parse(parse_args), parse_args)
  end

  @spec dispatch(term(), [String.t()]) :: :ok | :error
  defp dispatch({:ok, [:thread, :see], result}, _parse_args), do: Threads.run_thread_see(result)

  defp dispatch({:ok, [:thread, :export], result}, _parse_args),
    do: Threads.run_thread_export(result)

  defp dispatch({:ok, [:thread], result}, _parse_args), do: Threads.run_thread_see(result)
  defp dispatch({:ok, [:delete, :all], result}, _parse_args), do: Delete.run_delete_all(result)

  defp dispatch({:ok, [:delete, :thread], result}, _parse_args),
    do: Delete.run_delete_thread(result)

  defp dispatch({:ok, [:delete], result}, _parse_args), do: Delete.run_delete(result)

  defp dispatch(:help, parse_args), do: print_parser_help(parse_args, :ok)
  defp dispatch({:help, _subcommand_path}, parse_args), do: print_parser_help(parse_args, :ok)
  defp dispatch(:version, parse_args), do: print_parser_help(parse_args, :ok)
  defp dispatch({:error, _errors}, parse_args), do: print_parser_help(parse_args, :error)
  defp dispatch(_other, _parse_args), do: :ok

  @spec print_parser_help([String.t()], :ok | :error) :: :ok | :error
  defp print_parser_help(parse_args, status) do
    _ = Parser.print_and_parse!(parse_args)
    status
  end

  @doc """
  Decodes HTTP response bodies into maps/lists when needed.
  """
  @spec decode!(binary() | map() | list()) :: map() | list()
  def decode!(result) do
    case result do
      binary when is_binary(binary) ->
        JSON.decode!(binary)

      %{} = map ->
        map

      list when is_list(list) ->
        list

      other ->
        raise "Unexpected body type: #{inspect(other)}"
    end
  end

  @doc """
  Builds authorization/content headers for Mastodon API requests.
  """
  @spec build_header(String.t()) :: keyword(String.t())
  def build_header(token) do
    [
      authorization: "Bearer #{token}",
      "content-type": "application/json"
    ]
  end
end