defmodule Localiser.Web.Channels.ParticlesChannel do
  use Phoenix.Channel

  @impl true
  def join("particles:" <> tag_id, _params, socket) do
    Phoenix.PubSub.subscribe(Localiser.PubSub, "particles:#{tag_id}")
    {:ok, assign(socket, :tag_id, tag_id)}
  end

  @impl true
  def handle_info({:particles_updated, payload}, socket) do
    push(socket, "particles_updated", %{
      tag_id:    payload.tag_id,
      estimate:  payload.estimate,
      particles: payload.particles
    })
    {:noreply, socket}
  end

  def handle_info(_msg, socket), do: {:noreply, socket}
end