Timeline pagination

assets/css/clacks.scss

@@ -84,6 +84,10 @@ ul.status-list {
 	}
 }
 
+.pagination-link {
+	text-align: center;
+}
+
 .status {
 	padding: 0.5rem;
 	border: 1px solid #ddd;

lib/clacks_web/templates/frontend/_timeline.html.eex

@@ -1,3 +1,10 @@
+<% newer = prev_page_path(@conn, @statuses_with_authors) %>
+<%= if newer do %>
+  <p class="pagination-link">
+    <a href="<%= newer %>">Newer</a>
+  </p>
+<% end %>
+
 <ul class="status-list">
   <%= for {status, author} <- @statuses_with_authors do %>
     <li>
@@ -5,3 +12,11 @@
     </li>
   <% end %>
 </ul>
+
+<% older = next_page_path(@conn, @statuses_with_authors) %>
+<%= if older do %>
+  <p class="pagination-link">
+    <a href="<%= older %>">Older</a>
+  </p>
+<% end %>
+

lib/clacks_web/views/frontend_view.ex

@@ -1,6 +1,6 @@
 defmodule ClacksWeb.FrontendView do
   use ClacksWeb, :view
-  alias Clacks.Actor
+  alias Clacks.{Actor, Activity}
 
   @spec display_username(actor :: Actor.t()) :: String.t()
 
@@ -13,8 +13,6 @@ defmodule ClacksWeb.FrontendView do
     "@" <> name <> "@" <> host
   end
 
-  @absolute_timestamp_threshold 24 * 60 * 60
-
   def display_timestamp(str) when is_binary(str) do
     display_timestamp(Timex.parse!(str, "{ISO:Extended}"))
   end
@@ -43,4 +41,27 @@ defmodule ClacksWeb.FrontendView do
         Timex.format!(datetime, "%FT%T%:z", :strftime)
     end
   end
+
+  def prev_page_path(conn, activities) do
+    if Map.has_key?(conn.query_params, "max_id") do
+      Phoenix.Controller.current_path(conn, %{
+        since_id: activities |> List.first() |> activity_id()
+      })
+    else
+      nil
+    end
+  end
+
+  def next_page_path(conn, activities) do
+    if length(activities) < 20 do
+      nil
+    else
+      Phoenix.Controller.current_path(conn, %{
+        max_id: activities |> List.last() |> activity_id()
+      })
+    end
+  end
+
+  defp activity_id(%Activity{id: id}), do: id
+  defp activity_id({%Activity{id: id}, _}), do: id
 end