From d8024ac6f452ddd5091f7170b554799975923962 Mon Sep 17 00:00:00 2001
From: "Daniel J. Summers" <daniel@bitbadger.solutions>
Date: Mon, 25 Mar 2024 22:00:04 -0400
Subject: [PATCH] Add chapter ref to feed (#6)

---
 src/MyWebLog/Handlers/Feed.fs    | 25 ++++++++++++++++---------
 src/MyWebLog/Handlers/Helpers.fs |  3 +++
 src/MyWebLog/Handlers/Post.fs    |  2 +-
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/src/MyWebLog/Handlers/Feed.fs b/src/MyWebLog/Handlers/Feed.fs
index 8c55dbd..25f055f 100644
--- a/src/MyWebLog/Handlers/Feed.fs
+++ b/src/MyWebLog/Handlers/Feed.fs
@@ -163,17 +163,24 @@ let private addEpisode (webLog: WebLog) (podcast: PodcastOptions) (episode: Epis
     episode.Subtitle |> Option.iter (fun it -> item.ElementExtensions.Add("subtitle", Namespace.iTunes, it))
     episode.FormatDuration() |> Option.iter (fun it -> item.ElementExtensions.Add("duration", Namespace.iTunes, it))
     
-    match episode.ChapterFile with
-    | Some chapters ->
-        let url = toAbsolute webLog chapters
-        let typ =
-            match episode.ChapterType with
-            | Some mime -> Some mime
-            | None when chapters.EndsWith ".json" -> Some "application/json+chapters"
-            | None -> None
+    let chapterUrl, chapterMimeType =
+        match episode.Chapters, episode.ChapterFile with
+        | Some _, _ ->
+            Some $"{webLog.AbsoluteUrl post.Permalink}?chapters", Some JSON_CHAPTERS
+        | None, Some chapters ->
+            let typ =
+                match episode.ChapterType with
+                | Some mime -> Some mime
+                | None when chapters.EndsWith ".json" -> Some JSON_CHAPTERS
+                | None -> None
+            Some (toAbsolute webLog chapters), typ
+        | None, None -> None, None
+    
+    match chapterUrl with
+    | Some url ->
         let elt = xmlDoc.CreateElement("podcast", "chapters", Namespace.podcast)
         elt.SetAttribute("url", url)
-        typ |> Option.iter (fun it -> elt.SetAttribute("type", it))
+        chapterMimeType |> Option.iter (fun it -> elt.SetAttribute("type", it))
         item.ElementExtensions.Add elt
     | None -> ()
     
diff --git a/src/MyWebLog/Handlers/Helpers.fs b/src/MyWebLog/Handlers/Helpers.fs
index 13a0501..1a26bea 100644
--- a/src/MyWebLog/Handlers/Helpers.fs
+++ b/src/MyWebLog/Handlers/Helpers.fs
@@ -268,6 +268,9 @@ let redirectToGet url : HttpHandler = fun _ ctx -> task {
     return! redirectTo false (ctx.WebLog.RelativeUrl(Permalink url)) earlyReturn ctx
 }
 
+/// The MIME type for podcast episode JSON chapters
+let JSON_CHAPTERS = "application/json+chapters"
+
 
 /// Handlers for error conditions
 module Error =
diff --git a/src/MyWebLog/Handlers/Post.fs b/src/MyWebLog/Handlers/Post.fs
index 79bd624..b1ae54a 100644
--- a/src/MyWebLog/Handlers/Post.fs
+++ b/src/MyWebLog/Handlers/Post.fs
@@ -238,7 +238,7 @@ let chapters (post: Post) : HttpHandler = fun next ctx ->
             jsonFile["fileName"] <- absoluteUrl ep.Media ctx
             if defaultArg ep.ChapterWaypoints false then jsonFile["waypoints"] <- true
             jsonFile["chapters"] <- chapterData
-            json jsonFile next ctx
+            (setContentType JSON_CHAPTERS >=> json jsonFile) next ctx
         | None ->
             match ep.ChapterFile with
             | Some file -> redirectTo true file next ctx