3 files changed, 115 insertions, 6 deletions

diff --git a/lib/pleroma/web/ostatus/metadata.ex b/lib/pleroma/web/ostatus/metadata.ex
new file mode 100644
index 000000000..9935726fc
--- /dev/null
+++ b/lib/pleroma/web/ostatus/metadata.ex
@@ -0,0 +1,82 @@
+defmodule Pleroma.Web.Metadata do
+  alias Phoenix.HTML
+  alias Pleroma.{Formatter, User}
+  alias Pleroma.Web.MediaProxy
+
+  def build_tags(params) do
+    if(meta_enabled?(:opengraph), do: opengraph_tags(params), else: [])
+    |> Enum.map(&to_tag/1)
+    |> Enum.map(&HTML.safe_to_string/1)
+    |> Enum.join("\n")
+  end
+
+  def meta_enabled?(type) do
+    Pleroma.Config.get([:metadata, type], false)
+  end
+
+  # opengraph for single status
+  defp opengraph_tags(%{activity: activity, user: user}) do
+    with truncated_content = scrub_html_and_truncate(activity.data["object"]["content"]) do
+      [
+        {:meta,
+         [
+           property: "og:title",
+           content: "#{user.name} (@#{user.nickname}@#{pleroma_domain()}) post ##{activity.id}"
+         ], []},
+        {:meta, [property: "og:url", content: activity.data["id"]], []},
+        {:meta, [property: "og:description", content: truncated_content], []},
+        {:meta, [property: "og:image", content: user_avatar_url(user)], []},
+        {:meta, [property: "og:image:width", content: 120], []},
+        {:meta, [property: "og:image:height", content: 120], []},
+        {:meta, [property: "twitter:card", content: "summary"], []}
+      ]
+    end
+  end
+
+  # opengraph for user card
+  defp opengraph_tags(%{user: user}) do
+    with truncated_bio = scrub_html_and_truncate(user.bio) do
+      [
+        {:meta,
+         [
+           property: "og:title",
+           content: "#{user.name} (@#{user.nickname}@#{pleroma_domain()}) profile"
+         ], []},
+        {:meta, [property: "og:url", content: User.profile_url(user)], []},
+        {:meta, [property: "og:description", content: truncated_bio], []},
+        {:meta, [property: "og:image", content: user_avatar_url(user)], []},
+        {:meta, [property: "og:image:width", content: 120], []},
+        {:meta, [property: "og:image:height", content: 120], []},
+        {:meta, [property: "twitter:card", content: "summary"], []}
+      ]
+    end
+  end
+
+  def to_tag(data) do
+    with {name, attrs, _content = []} <- data do
+      HTML.Tag.tag(name, attrs)
+    else
+      {name, attrs, content} ->
+        HTML.Tag.content_tag(name, content, attrs)
+
+      _ ->
+        raise ArgumentError, message: "make_tag invalid args"
+    end
+  end
+
+  defp scrub_html_and_truncate(content) do
+    content
+    # html content comes from DB already encoded, decode first and scrub after
+    |> HtmlEntities.decode()
+    |> Pleroma.HTML.strip_tags()
+    |> Formatter.truncate()
+  end
+
+  defp user_avatar_url(user) do
+    User.avatar_url(user) |> MediaProxy.url()
+  end
+
+  def pleroma_domain do
+    Pleroma.Web.Endpoint.host()
+  end
+end
diff --git a/lib/pleroma/web/ostatus/ostatus_controller.ex b/lib/pleroma/web/ostatus/ostatus_controller.ex
index 332cbef0e..be648a6ee 100644
--- a/lib/pleroma/web/ostatus/ostatus_controller.ex
+++ b/lib/pleroma/web/ostatus/ostatus_controller.ex
@@ -20,7 +20,11 @@ defmodule Pleroma.Web.OStatus.OStatusController do
   def feed_redirect(conn, %{"nickname" => nickname}) do
     case get_format(conn) do
       "html" ->
-        Fallback.RedirectController.redirector(conn, nil)
+        with %User{} = user <- User.get_cached_by_nickname_or_id(nickname) do
+          Fallback.RedirectController.redirector_with_meta(conn, %{user: user})
+        else
+          nil -> {:error, :not_found}
+        end
 
       "activity+json" ->
         ActivityPubController.call(conn, :user)
@@ -142,9 +146,7 @@ defmodule Pleroma.Web.OStatus.OStatusController do
          %User{} = user <- User.get_cached_by_ap_id(activity.data["actor"]) do
       case format = get_format(conn) do
         "html" ->
-          conn
-          |> put_resp_content_type("text/html")
-          |> send_file(200, Pleroma.Plugs.InstanceStatic.file_path("index.html"))
+          Fallback.RedirectController.redirector_with_meta(conn, %{activity: activity, user: user})
 
         _ ->
           represent_activity(conn, format, activity, user)
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index a5f4d8126..5ef99bec5 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -391,7 +391,11 @@ defmodule Pleroma.Web.Router do
   end
 
   pipeline :ostatus do
-    plug(:accepts, ["xml", "atom", "html", "activity+json"])
+    plug(:accepts, ["html", "xml", "atom", "activity+json"])
+  end
+
+  pipeline :oembed do
+    plug(:accepts, ["json", "xml"])
   end
 
   scope "/", Pleroma.Web do
@@ -409,6 +413,12 @@ defmodule Pleroma.Web.Router do
     post("/push/subscriptions/:id", Websub.WebsubController, :websub_incoming)
   end
 
+  scope "/", Pleroma.Web do
+    pipe_through(:oembed)
+
+    get("/oembed", OEmbed.OEmbedController, :url)
+  end
+
   pipeline :activitypub do
     plug(:accepts, ["activity+json"])
     plug(Pleroma.Web.Plugs.HTTPSignaturePlug)
@@ -503,11 +513,26 @@ end
 
 defmodule Fallback.RedirectController do
   use Pleroma.Web, :controller
+  alias Pleroma.Web.Metadata
 
   def redirector(conn, _params) do
     conn
     |> put_resp_content_type("text/html")
-    |> send_file(200, Pleroma.Plugs.InstanceStatic.file_path("index.html"))
+    |> send_file(200, index_file_path())
+  end
+
+  def redirector_with_meta(conn, params) do
+    {:ok, index_content} = File.read(index_file_path())
+    tags = Metadata.build_tags(params)
+    response = String.replace(index_content, "<!--server-generated-meta-->", tags)
+
+    conn
+    |> put_resp_content_type("text/html")
+    |> send_resp(200, response)
+  end
+
+  def index_file_path do
+    Pleroma.Plugs.InstanceStatic.file_path("index.html")
   end
 
   def registration_page(conn, params) do