Linkify chapters in Zulip new episode messages

lib/changelog/zulip/messages.ex

@@ -8,16 +8,20 @@ defmodule Changelog.Zulip.Messages do
 
   def new_episode(episode) do
     [
-      "#{episode.summary} 🔗 #{EpisodeView.share_url(episode)}",
-      chapters(episode.audio_chapters)
+      summary(episode),
+      chapters(episode)
     ]
     |> ListKit.compact_join("\n\n")
   end
 
-  def chapters(nil), do: nil
-  def chapters([]), do: nil
+  def summary(episode) do
+    "#{episode.summary} 🔗 #{episode_url(episode)}"
+  end
+
+  def chapters(%{audio_chapters: nil}), do: nil
+  def chapters(%{audio_chapters: []}), do: nil
 
-  def chapters(chapters, padding \\ 2) do
+  def chapters(episode = %{audio_chapters: chapters}, padding \\ 2) do
     numbers =
       chapters
       |> Enum.with_index(1)
@@ -60,8 +64,16 @@ defmodule Changelog.Zulip.Messages do
       |> Enum.map(fn {chapter, index} ->
         [
           pad(Enum.at(numbers, index), numbers_length),
-          pad(Enum.at(starts, index), starts_length),
-          linkify(pad(Enum.at(titles, index), titles_length), chapter.title, chapter.link_url),
+          linkify(
+            pad(Enum.at(starts, index), starts_length),
+            Enum.at(starts, index),
+            episode_url(episode, chapter.starts_at)
+          ),
+          linkify(
+            pad(Enum.at(titles, index), titles_length),
+            chapter.title,
+            chapter.link_url
+          ),
           pad(Enum.at(runs, index), runs_length)
         ]
         |> Enum.join("|")
@@ -73,6 +85,14 @@ defmodule Changelog.Zulip.Messages do
     |> Enum.join("\n")
   end
 
+  defp episode_url(episode, starts_at \\ nil) do
+    if starts_at do
+      EpisodeView.share_url(episode) <> "#t=#{round(starts_at)}"
+    else
+      EpisodeView.share_url(episode)
+    end
+  end
+
   defp linkify(string, _title, nil), do: string
 
   defp linkify(string, title, link) do

test/changelog/zulip/messages_test.exs

@@ -1,25 +1,34 @@
 defmodule Changelog.Zulip.MessagesTest do
   use ExUnit.Case
 
+  import Mock
   import Changelog.Factory
 
   alias Changelog.Zulip.Messages
 
   describe "chapters/1" do
+    setup_with_mocks([
+      {ChangelogWeb.EpisodeView, [], [share_url: fn _ -> "https://cpu.fm/1" end]}
+    ]) do
+      :ok
+    end
+
     test "is nil when there are no chapters" do
-      assert Messages.chapters([]) == nil
+      episode = build(:episode, audio_chapters: [])
+      assert Messages.chapters(episode) == nil
     end
 
     test "is a markdown table when one chapter exists" do
       ch1 = build(:episode_chapter, title: "Chapter 1", starts_at: 0, ends_at: 0)
+      episode = build(:episode, audio_chapters: [ch1])
 
       table = """
       | Ch | Start | Title     | Runs  |
       | -- | ----- | --------- | ----- |
-      | 01 | 00:00 | Chapter 1 | 00:00 |
+      | 01 | [00:00](https://cpu.fm/1#t=0) | Chapter 1 | 00:00 |
       """
 
-      assert Messages.chapters([ch1]) == String.trim_trailing(table, "\n")
+      assert Messages.chapters(episode) == String.trim_trailing(table, "\n")
     end
 
     test "is a markdown table when multiple chapter exists" do
@@ -28,14 +37,16 @@ defmodule Changelog.Zulip.MessagesTest do
 
       ch2 = build(:episode_chapter, title: "Go shorty", starts_at: 37, ends_at: 247)
 
+      episode = build(:episode, audio_chapters: [ch1, ch2])
+
       table = """
       | Ch | Start | Title                         | Runs  |
       | -- | ----- | ----------------------------- | ----- |
-      | 01 | 00:00 | Yo that's a rather long title | 00:36 |
-      | 02 | 00:37 | Go shorty                     | 03:30 |
+      | 01 | [00:00](https://cpu.fm/1#t=0) | Yo that's a rather long title | 00:36 |
+      | 02 | [00:37](https://cpu.fm/1#t=37) | Go shorty                     | 03:30 |
       """
 
-      assert Messages.chapters([ch1, ch2]) == String.trim_trailing(table, "\n")
+      assert Messages.chapters(episode) == String.trim_trailing(table, "\n")
     end
 
     test "it includes markdown links when chapter has one" do
@@ -44,19 +55,21 @@ defmodule Changelog.Zulip.MessagesTest do
           title: "Link me up! This is the longest",
           link_url: "https://link.zelda",
           starts_at: 0,
-          ends_at: 36
+          ends_at: 136
         )
 
-      ch2 = build(:episode_chapter, title: "No link here...", starts_at: 37, ends_at: 247)
+      ch2 = build(:episode_chapter, title: "No link here...", starts_at: 137, ends_at: 247)
+
+      episode = build(:episode, audio_chapters: [ch1, ch2])
 
       table = """
       | Ch | Start | Title                           | Runs  |
       | -- | ----- | ------------------------------- | ----- |
-      | 01 | 00:00 | [Link me up! This is the longest](https://link.zelda) | 00:36 |
-      | 02 | 00:37 | No link here...                 | 03:30 |
+      | 01 | [00:00](https://cpu.fm/1#t=0) | [Link me up! This is the longest](https://link.zelda) | 02:16 |
+      | 02 | [02:17](https://cpu.fm/1#t=137) | No link here...                 | 01:50 |
       """
 
-      assert Messages.chapters([ch1, ch2]) == String.trim_trailing(table, "\n")
+      assert Messages.chapters(episode) == String.trim_trailing(table, "\n")
     end
   end
 end