I don't know if i like this.

.gitignore

@@ -33,6 +33,8 @@ Makefile.bac
 
 /images
 /_nerves-tmp
+nerves_system_*
+NERVES_SYSTEM_*
 Makefile
 release-*
 dump.rdb

lib/farmbot/bootstrap/configurator.ex

@@ -41,6 +41,7 @@ defmodule  Farmbot.Bootstrap.Configurator do
       _ ->
         Logger.info "Building new config."
         import Supervisor.Spec
+        :ets.new(:session, [:named_table, :public, read_concurrency: true])
         children = [
           Plug.Adapters.Cowboy.child_spec(:http, Farmbot.Bootstrap.Configurator.Router, [], [port: 4001])
         ]

lib/farmbot/bootstrap/configurator/router.ex

@@ -3,17 +3,59 @@ defmodule Farmbot.Bootstrap.Configurator.Router do
 
   use Plug.Router
 
-  plug Plug.Static, from: {:farmbot, "priv/static"}, at: "/static"
+  plug Plug.Static, from: {:farmbot, "priv/static"}, at: "/"
+  plug Plug.Session, store: :ets, key: "session", table: :session
   plug :match
   plug :dispatch
 
   import Farmbot.Bootstrap.Configurator.HTML
 
   get "/" do
-    conn |> send_resp(200, render("index"))
+    conn = conn |> fetch_session()
+    # session = conn |> get_session("session")
+    conn
+    |> put_session("session", 0)
+    |> send_resp(200, render("page0"))
   end
 
-  match _ do
-    send_resp(conn, 404, "oops")
+  get "/previous" do
+    conn = conn |> fetch_session()
+    session = conn |> get_session("session")
+    cond do
+      is_nil(session) ->
+        conn
+        |> put_session("session", 0)
+        |> send_resp(200, render("page0"))
+      is_number(session) ->
+        conn |> handle_step(session - 1)
+    end
   end
+
+  get "/next" do
+    conn = conn |> fetch_session()
+    session = conn |> get_session("session")
+    cond do
+      is_nil(session) ->
+        conn
+        |> put_session("session", 0)
+        |> send_resp(200, render("page0"))
+      is_number(session) ->
+        conn |> handle_step(session + 1)
+    end
+  end
+
+  defp handle_step(conn, num) do
+    try do
+      conn
+      |> put_session("session", num)
+      |> send_resp(200, render("page#{num}"))
+    rescue
+      _ ->
+        conn
+        |> put_session("session", 0)
+        |> send_resp(200, render("page0"))
+    end
+  end
+
+  match _, do: send_resp(conn, 404, "Page not found.")
 end

lib/farmbot/bootstrap/configurator/store.ex

@@ -0,0 +1,78 @@
+defmodule Plug.Session.ETS do
+  @moduledoc """
+  Stores the session in an in-memory ETS table.
+  This store does not create the ETS table; it expects that an
+  existing named table with public properties is passed as an
+  argument.
+  We don't recommend using this store in production as every
+  session will be stored in ETS and never cleaned until you
+  create a task responsible for cleaning up old entries.
+  Also, since the store is in-memory, it means sessions are
+  not shared between servers. If you deploy to more than one
+  machine, using this store is again not recommended.
+  This store, however, can be used as an example for creating
+  custom storages, based on Redis, Memcached, or a database
+  itself.
+  ## Options
+    * `:table` - ETS table name (required)
+  For more information on ETS tables, visit the Erlang documentation at
+  http://www.erlang.org/doc/man/ets.html.
+  ## Storage
+  The data is stored in ETS in the following format:
+      {sid :: String.t, data :: map, timestamp :: :erlang.timestamp}
+  The timestamp is updated whenever there is a read or write to the
+  table and it may be used to detect if a session is still active.
+  ## Examples
+      # Create an ETS table when the application starts
+      :ets.new(:session, [:named_table, :public, read_concurrency: true])
+      # Use the session plug with the table name
+      plug Plug.Session, store: :ets, key: "sid", table: :session
+  """
+
+  @behaviour Plug.Session.Store
+
+  @max_tries 100
+
+  def init(opts) do
+    Keyword.fetch!(opts, :table)
+  end
+
+  def get(_conn, sid, table) do
+    case :ets.lookup(table, sid) do
+      [{^sid, data, _timestamp}] ->
+        :ets.update_element(table, sid, {3, now()})
+        {sid, data}
+      [] ->
+        {nil, %{}}
+    end
+  end
+
+  def put(_conn, nil, data, table) do
+    put_new(data, table)
+  end
+
+  def put(_conn, sid, data, table) do
+    :ets.insert(table, {sid, data, now()})
+    sid
+  end
+
+  def delete(_conn, sid, table) do
+    :ets.delete(table, sid)
+    :ok
+  end
+
+  defp put_new(data, table, counter \\ 0)
+      when counter < @max_tries do
+    sid = Base.encode64(:crypto.strong_rand_bytes(96))
+
+    if :ets.insert_new(table, {sid, data, now()}) do
+      sid
+    else
+      put_new(data, table, counter + 1)
+    end
+  end
+
+  defp now() do
+    :os.timestamp()
+  end
+end

priv/templates/page.html.eex

@@ -4,7 +4,13 @@
       Configure your Farmbot! - <%= page %>
     </title>
   </head>
-  <div id=<%= page %>>
-  <%= render.() %>
-  </div>
+
+  <body>
+    <div id="content">
+      <div id=<%= page %>>
+        <%= render.() %>
+      </div>
+    </div>
+  </body>
+
 </html>

priv/templates/page/index.html.eex

@@ -1 +0,0 @@
-whoops

priv/templates/page/page0.html.eex

@@ -0,0 +1,5 @@
+Get ready to configure your Farmbot!
+
+<form action="next">
+  <button> Go! </button>
+</form>

priv/templates/page/page1.html.eex

@@ -0,0 +1,5 @@
+Lets configure Network!
+<form action="network" method="post">
+  <input> SSID </input>
+  <input> PSK </input>
+</form>

priv/templates/page/page2.html.eex

@@ -0,0 +1 @@
+2