[Enhancement] Add sorting, pagination, and new attributes to sources index table (#510)

* WIP - started improving handling of sorting for sources index table

* WIP - Added UI to table to indicate sort column and direction

* Refactored toggle liveview into a livecomponent

* Added sorting for all table attrs

* Added pagination to the sources table

* Added tests for updated liveviews and live components

* Add tests for new helper methods

* Added fancy new CSS to my sources table

* Added size to sources table

* Adds relative div to ensure that sorting arrow doesn't run away

* Fixed da tests

lib/pinchflat_web/helpers/pagination_helpers.ex

@@ -0,0 +1,45 @@
+defmodule PinchflatWeb.Helpers.PaginationHelpers do
+  @moduledoc """
+  Methods for working with pagination, usually in the context of LiveViews or LiveComponents.
+
+  These methods are fairly simple, but they're commonly repeated across different Live entities
+  """
+
+  alias Pinchflat.Repo
+  alias Pinchflat.Utils.NumberUtils
+
+  @doc """
+  Given a query, a page number, and a number of records per page, returns a map of pagination attributes.
+
+  Returns map()
+  """
+  def get_pagination_attributes(query, page, records_per_page) do
+    total_record_count = Repo.aggregate(query, :count, :id)
+    total_pages = max(ceil(total_record_count / records_per_page), 1)
+    clamped_page = NumberUtils.clamp(page, 1, total_pages)
+
+    %{
+      page: clamped_page,
+      total_pages: total_pages,
+      total_record_count: total_record_count,
+      limit: records_per_page,
+      offset: (clamped_page - 1) * records_per_page
+    }
+  end
+
+  @doc """
+  Given a current page number, a direction to move in, and the total number of pages, returns the updated page number.
+  The updated page number is clamped to the range [1, total_pages].
+
+  Returns integer()
+  """
+  def update_page_number(current_page, direction, total_pages) do
+    updated_page =
+      case to_string(direction) do
+        "inc" -> current_page + 1
+        "dec" -> current_page - 1
+      end
+
+    NumberUtils.clamp(updated_page, 1, total_pages)
+  end
+end