siren

defmodule Siren.Utils do
  alias Siren.Utils

  def action_name(action, class) do
    "#{action}-#{Enum.join(class, "-")}"
  end

  def action_method(action) do
    cond do
      action == :create -> "POST"
      action == :edit -> "PATCH"
      action == :replace -> "PUT"
      action == :delete -> "DELETE"
      true -> "GET"
    end
  end

  def remove_empty(map) do
    Enum.reduce(map, %{}, fn {key, value}, acc ->
      if value == nil || value == [] || value == %{} do
        acc
      else
        Map.put(acc, key, value)
      end
    end)
  end

  def get_query(uri) do
    if uri.query do
      URI.decode_query(uri.query)
    else
      %{}
    end
  end

  if Code.ensure_loaded?(Plug.Conn) do
    alias Plug.Conn

    def get_int_param(query, key, default) do
      value = Map.get(query, key, default)

      if is_integer(value) do
        value
      else
        value
        |> Integer.parse()
        |> elem(0)
      end
    end

    def get_page_items(query, opts) do
      query
      |> Utils.get_int_param(:page_items, Keyword.get(opts, :page_items, 20))
    end

    def opts_from_conn(conn, opts) do
      url = Conn.request_url(conn)
      query = url |> URI.parse() |> Utils.get_query()

      opts
      |> Keyword.put(:base_url, url)
      |> Keyword.put(:page, Utils.get_int_param(query, :page, 1))
      |> Keyword.put(:page_items, Utils.get_page_items(query, opts))
    end
  end
end