From 7c547f2d805c72ee36d46059a8b900850d2138c3 Mon Sep 17 00:00:00 2001
From: Claudio Ortolina <cloud8421@gmail.com>
Date: Mon, 5 May 2025 19:19:12 +0100
Subject: [PATCH] Redirect to Last.fm and receive a token (unused)

---
 config/runtime.exs                                         | 4 ++++
 lib/last_fm.ex                                             | 5 +++++
 lib/last_fm/config.ex                                      | 6 ++++++
 lib/music_library_web/controllers/last_fm_controller.ex    | 7 +++++++
 .../controllers/session_html/new.html.heex                 | 3 +++
 lib/music_library_web/router.ex                            | 2 ++
 6 files changed, 27 insertions(+)
 create mode 100644 lib/music_library_web/controllers/last_fm_controller.ex

diff --git a/config/runtime.exs b/config/runtime.exs
index 71c3d955..c3a193e3 100644
--- a/config/runtime.exs
+++ b/config/runtime.exs
@@ -24,6 +24,10 @@ if api_key = System.get_env("LAST_FM_API_KEY") do
   config :music_library, LastFm, api_key: api_key
 end
 
+if shared_secret = System.get_env("LAST_FM_SHARED_SECRET") do
+  config :music_library, LastFm, shared_secret: shared_secret
+end
+
 if user = System.get_env("LAST_FM_USER") do
   config :music_library, LastFm, user: user
 end
diff --git a/lib/last_fm.ex b/lib/last_fm.ex
index a1b64e4a..f9f4f4af 100644
--- a/lib/last_fm.ex
+++ b/lib/last_fm.ex
@@ -41,5 +41,10 @@ defmodule LastFm do
     end
   end
 
+  def auth_url do
+    last_fm_config = last_fm_config()
+    "https://www.last.fm/api/auth/?api_key=" <> last_fm_config.api_key
+  end
+
   defp last_fm_config, do: LastFm.Config.resolve(:music_library)
 end
diff --git a/lib/last_fm/config.ex b/lib/last_fm/config.ex
index 570bf5f1..a7822477 100644
--- a/lib/last_fm/config.ex
+++ b/lib/last_fm/config.ex
@@ -1,6 +1,7 @@
 defmodule LastFm.Config do
   @type t :: %__MODULE__{
           api_key: String.t(),
+          shared_secret: String.t(),
           user: String.t(),
           auto_refresh: boolean(),
           refresh_interval: pos_integer(),
@@ -10,6 +11,7 @@ defmodule LastFm.Config do
 
   @enforce_keys [:api_key, :user]
   defstruct api_key: "",
+            shared_secret: "",
             user: "",
             auto_refresh: true,
             refresh_interval: 60_000,
@@ -21,6 +23,10 @@ defmodule LastFm.Config do
               type: :string,
               required: true
             ],
+            shared_secret: [
+              type: :string,
+              required: true
+            ],
             user: [
               type: :string,
               required: true
diff --git a/lib/music_library_web/controllers/last_fm_controller.ex b/lib/music_library_web/controllers/last_fm_controller.ex
new file mode 100644
index 00000000..3c59aa5f
--- /dev/null
+++ b/lib/music_library_web/controllers/last_fm_controller.ex
@@ -0,0 +1,7 @@
+defmodule MusicLibraryWeb.LastFmController do
+  use MusicLibraryWeb, :controller
+
+  def callback(conn, %{"token" => _token}) do
+    conn |> redirect(to: ~p"/")
+  end
+end
diff --git a/lib/music_library_web/controllers/session_html/new.html.heex b/lib/music_library_web/controllers/session_html/new.html.heex
index d539ae68..6e8ba6e8 100644
--- a/lib/music_library_web/controllers/session_html/new.html.heex
+++ b/lib/music_library_web/controllers/session_html/new.html.heex
@@ -35,5 +35,8 @@
         </button>
       </div>
     </.form>
+    <a href={LastFm.auth_url()} class="flex items-center justify-center">
+      Connect to Last.fm
+    </a>
   </div>
 </div>
diff --git a/lib/music_library_web/router.ex b/lib/music_library_web/router.ex
index 4cfa3e82..3784d993 100644
--- a/lib/music_library_web/router.ex
+++ b/lib/music_library_web/router.ex
@@ -29,6 +29,8 @@ defmodule MusicLibraryWeb.Router do
     get "/login", SessionController, :new
     post "/sessions/create", SessionController, :create
 
+    get "/auth/last_fm/callback", LastFmController, :callback
+
     scope "/" do
       pipe_through :logged_in