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diff --git a/lib/pleroma/web/metadata/providers/twitter_card.ex b/lib/pleroma/web/metadata/providers/twitter_card.ex
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+# Pleroma: A lightweight social networking server
+
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.Metadata.Providers.TwitterCard do
+  alias Pleroma.User
+  alias Pleroma.Web.Metadata
+  alias Pleroma.Web.Metadata.Providers.Provider
+  alias Pleroma.Web.Metadata.Utils
+
+  @behaviour Provider
+  @media_types ["image", "audio", "video"]
+
+  @impl Provider
+  def build_tags(%{activity_id: id, object: object, user: user}) do
+    attachments = build_attachments(id, object)
+    scrubbed_content = Utils.scrub_html_and_truncate(object)
+    # Zero width space
+    content =
+      if scrubbed_content != "" and scrubbed_content != "\u200B" do
+        "“" <> scrubbed_content <> "”"
+      else
+        ""
+      end
+
+    [
+      title_tag(user),
+      {:meta, [property: "twitter:description", content: content], []}
+    ] ++
+      if attachments == [] or Metadata.activity_nsfw?(object) do
+        [
+          image_tag(user),
+          {:meta, [property: "twitter:card", content: "summary"], []}
+        ]
+      else
+        attachments
+      end
+  end
+
+  @impl Provider
+  def build_tags(%{user: user}) do
+    with truncated_bio = Utils.scrub_html_and_truncate(user.bio) do
+      [
+        title_tag(user),
+        {:meta, [property: "twitter:description", content: truncated_bio], []},
+        image_tag(user),
+        {:meta, [property: "twitter:card", content: "summary"], []}
+      ]
+    end
+  end
+
+  defp title_tag(user) do
+    {:meta, [property: "twitter:title", content: Utils.user_name_string(user)], []}
+  end
+
+  def image_tag(user) do
+    {:meta, [property: "twitter:image", content: Utils.attachment_url(User.avatar_url(user))], []}
+  end
+
+  defp build_attachments(id, %{data: %{"attachment" => attachments}}) do
+    Enum.reduce(attachments, [], fn attachment, acc ->
+      rendered_tags =
+        Enum.reduce(attachment["url"], [], fn url, acc ->
+          # TODO: Add additional properties to objects when we have the data available.
+          case Utils.fetch_media_type(@media_types, url["mediaType"]) do
+            "audio" ->
+              [
+                {:meta, [property: "twitter:card", content: "player"], []},
+                {:meta, [property: "twitter:player:width", content: "480"], []},
+                {:meta, [property: "twitter:player:height", content: "80"], []},
+                {:meta, [property: "twitter:player", content: player_url(id)], []}
+                | acc
+              ]
+
+            "image" ->
+              [
+                {:meta, [property: "twitter:card", content: "summary_large_image"], []},
+                {:meta,
+                 [
+                   property: "twitter:player",
+                   content: Utils.attachment_url(url["href"])
+                 ], []}
+                | acc
+              ]
+
+            # TODO: Need the true width and height values here or Twitter renders an iFrame with
+            # a bad aspect ratio
+            "video" ->
+              [
+                {:meta, [property: "twitter:card", content: "player"], []},
+                {:meta, [property: "twitter:player", content: player_url(id)], []},
+                {:meta, [property: "twitter:player:width", content: "480"], []},
+                {:meta, [property: "twitter:player:height", content: "480"], []}
+                | acc
+              ]
+
+            _ ->
+              acc
+          end
+        end)
+
+      acc ++ rendered_tags
+    end)
+  end
+
+  defp build_attachments(_id, _object), do: []
+
+  defp player_url(id) do
+    Pleroma.Web.Router.Helpers.o_status_url(Pleroma.Web.Endpoint, :notice_player, id)
+  end
+end