Redirect properly to correct endpoint depending on content-type

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/mobilizon_web/controllers/page_controller.ex

@@ -3,6 +3,11 @@ defmodule MobilizonWeb.PageController do
   Controller to load our webapp
   """
   use MobilizonWeb, :controller
+  alias Mobilizon.Service.Metadata
+  alias Mobilizon.Actors
+  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Events
+  alias Mobilizon.Events.{Event, Comment}
 
   plug(:put_layout, false)
 
@@ -11,4 +16,71 @@ defmodule MobilizonWeb.PageController do
     |> put_resp_content_type("text/html")
     |> send_file(200, "priv/static/index.html")
   end
+
+  def actor(conn, %{"name" => name}) do
+    case get_format(conn) do
+      "html" ->
+        with {status, %Actor{} = actor} when status in [:ok, :commit] <-
+               Actors.get_cached_local_actor_by_name(name) do
+          render_with_meta(conn, actor)
+        end
+
+      "activity+json" ->
+        MobilizonWeb.ActivityPubController.call(conn, :actor)
+
+      _ ->
+        {:error, :not_found}
+    end
+  end
+
+  def event(conn, %{"uuid" => uuid}) do
+    case get_format(conn) do
+      "html" ->
+        with {status, %Event{} = event} when status in [:ok, :commit] <-
+               Events.get_cached_event_full_by_uuid(uuid),
+             true <- event.visibility in [:public, :unlisted] do
+          render_with_meta(conn, event)
+        end
+
+      "activity+json" ->
+        MobilizonWeb.ActivityPubController.call(conn, :event)
+
+      _ ->
+        {:error, :not_found}
+    end
+  end
+
+  def comment(conn, %{"uuid" => uuid}) do
+    case get_format(conn) do
+      "html" ->
+        with {status, %Comment{} = comment} when status in [:ok, :commit] <-
+               Events.get_cached_comment_full_by_uuid(uuid) do
+          # Comments are always public for now
+          # TODO : Make comments maybe restricted
+          # true <- comment.public do
+          render_with_meta(conn, comment)
+        end
+
+      "activity+json" ->
+        MobilizonWeb.ActivityPubController.call(conn, :comment)
+
+      _ ->
+        {:error, :not_found}
+    end
+  end
+
+  # Inject OpenGraph information
+  defp render_with_meta(conn, object) do
+    {:ok, index_content} = File.read(index_file_path())
+    tags = Metadata.build_tags(object)
+    response = String.replace(index_content, "<!--server-generated-meta-->", tags)
+
+    conn
+    |> put_resp_content_type("text/html")
+    |> send_resp(200, response)
+  end
+
+  defp index_file_path() do
+    Path.join(Application.app_dir(:mobilizon, "priv/static/"), "index.html")
+  end
 end