clacks/lib/clacks_web/views/frontend_view.ex

defmodule ClacksWeb.FrontendView do
  use ClacksWeb, :view
  alias Clacks.Actor

  @spec display_username(actor :: Actor.t()) :: String.t()

  def display_username(%Actor{local: true, data: %{"name" => name}}) do
    "@" <> name
  end

  def display_username(%Actor{local: false, ap_id: ap_id, data: %{"name" => name}}) do
    %URI{host: host} = URI.parse(ap_id)
    "@" <> name <> "@" <> host
  end

  @absolute_timestamp_threshold 24 * 60 * 60

  def display_timestamp(str) when is_binary(str) do
    display_timestamp(Timex.parse!(str, "{ISO:Extended}"))
  end

  def display_timestamp(datetime) do
    diff = Timex.diff(Timex.now(), datetime, :seconds)

    cond do
      diff < 60 ->
        # less than a minute, seconds
        "#{diff}sec"

      diff < 60 * 60 ->
        # less than an hour, minutes
        "#{Integer.floor_div(diff, 60)}min"

      diff < 60 * 60 * 24 ->
        # less than a day, hours
        "#{Integer.floor_div(diff, 60 * 60)}hr"

      diff < 60 * 60 * 24 * 7 ->
        # less than a week, days
        "#{Integer.floor_div(diff, 60 * 60 * 24)}d"

      true ->
        Timex.format!(datetime, "%FT%T%:z", :strftime)
    end
  end
end