Add ability to stop the morse.

morse/lib/morse/server.ex

@@ -5,8 +5,8 @@ defmodule Morse.Server do
     GenServer.start_link(__MODULE__, {nil, 0}, name: __MODULE__)
   end
 
-  def start_morse do
+  def toggle_morse do
-    GenServer.call(__MODULE__, :start)
+    GenServer.call(__MODULE__, :toggle)
   end
 
   def update_progress(progress) do
@@ -27,9 +27,11 @@ defmodule Morse.Server do
   end
 
   @impl true
-  def handle_call(:start, _from, {pid, _progress} = state) do
+  def handle_call(:toggle, _from, {pid, _progress}) do
     if worker_alive?(pid) do
-      {:reply, {:error, :already_started}, state}
+      Morse.Worker.kill(pid)
+      apply(pubsub(), :broadcast, [Ui.PubSub, "morse_progress", 0])
+      {:reply, :ok, {nil, 0}}
     else
       pid = spawn(&Morse.Worker.signal/0)
       {:reply, :ok, {pid, 0}}

morse/lib/morse/worker.ex

@@ -32,6 +32,11 @@ defmodule Morse.Worker do
     update_progress(100, 100)
   end
 
+  def kill(pid) do
+    Process.exit(pid, :kill)
+    toggle_lamp(@off)
+  end
+
   defp signal_symbol({?., _index}, _length) do
     toggle_lamp(@on)
     Process.sleep(@sleep_short)

ui/assets/css/ruby.css

@@ -35,8 +35,8 @@ p {
   height: 100px;
 }
 
-.button[disabled=disabled] {
+.button.stop {
-  background-color: gray;
+  background-color: red;
 }
 
 #hintbutton {

ui/lib/ui_web/live/morse_live.ex

@@ -12,10 +12,11 @@ defmodule UiWeb.MorseLive do
     {:ok, assign(socket, default_assigns(ip))}
   end
 
-  def handle_event("start_morse", _value, %{assigns: %{ip: ip}} = socket) do
+  def handle_event("toggle_morse", _value, %{assigns: %{ip: ip}} = socket) do
-    if :ok == Morse.Server.start_morse() do
+    if Morse.Server.in_progress?() do
       spawn fn -> Ui.TelegramBot.message("#{ip} pressed the button!") end
     end
+    Morse.Server.toggle_morse()
 
     {:noreply, socket}
   end

ui/lib/ui_web/templates/page/morse.html.leex

@@ -4,9 +4,9 @@
 
 <div id="buttonwrap">
   <%= if @in_progress? do %>
-  <button phx-click="start_morse" class="button" <%= if @in_progress?, do: ~s(disabled=disabled) %>>In progress...</button>
+    <button phx-click="toggle_morse" class="button stop">Stop</button>
   <% else %>
-    <button phx-click="start_morse" class="button">Start</button>
+    <button phx-click="toggle_morse" class="button">Start</button>
   <% end %>
   <div id="response-block">
     <h2>Progress:</h2>