From 2d245ea8e46c19ddd7dfdbf52987bb346c8f8a4a Mon Sep 17 00:00:00 2001
From: Manav Rathi <manav@mnvr.in>
Date: Mon, 24 Mar 2025 15:36:30 +0530
Subject: [PATCH] URL

---
 web/packages/gallery/services/file-data.ts | 55 +++++++++++++++++++++-
 web/packages/gallery/services/video.ts     | 32 ++++---------
 2 files changed, 64 insertions(+), 23 deletions(-)

diff --git a/web/packages/gallery/services/file-data.ts b/web/packages/gallery/services/file-data.ts
index 724db99a73..d9444474fe 100644
--- a/web/packages/gallery/services/file-data.ts
+++ b/web/packages/gallery/services/file-data.ts
@@ -82,7 +82,9 @@ export const fetchFilesData = async (
  *
  * Unlike {@link fetchFilesData}, this uses a HTTP GET request.
  *
- * Returns `undefined` if no video preview has been generated for this file yet.
+ * Returns `undefined` if no file data of the given type has been uploaded for
+ * this file yet (e.g. if type was "vid_preview", this would indicate that a
+ * video preview has been generated for this file yet).
  */
 export const fetchFileData = async (
     type: FileDataType,
@@ -134,3 +136,54 @@ export const putFileData = async (
     });
     ensureOk(res);
 };
+
+/**
+ * Fetch the preview file data the given file.
+ *
+ * @param type The {@link FileDataType} which we want.
+ *
+ * @param fileIDs The id of the files for which we want the file preview data.
+ *
+ * @returns the (presigned) URL to the preview data, or undefined if there is
+ * not preview data of the given type for the given file yet.
+ *
+ * [Note: File data vs file preview data]
+ *
+ * In museum's ontology, there is a distinction between two concepts:
+ *
+ * S3 metadata (museum term, the APIs call it "file data") is data that museum
+ * uploads on behalf of the client. e.g.,
+ *
+ * - ML data.
+ *
+ * - Preview video playlist.
+ *
+ * S3 file data (museum term, the APIs call it "file preview data") is data that
+ * a client itself uploads. e.g.,
+ *
+ * - The preview video itself.
+ *
+ * - Additional preview images.
+ *
+ * [Note: Video playlist and preview]
+ *
+ * For a streaming video, both these concepts are needed:
+ *
+ * - The encrypted HLS playlist is stored as "file data" of type "vid_preview",
+ *
+ * - The encrypted video chunks that the playlist refers to are stored as "file
+ *   preview data" of type "vid_preview".
+ */
+export const fetchFilePreviewData = async (
+    type: FileDataType,
+    fileID: number,
+): Promise<string | undefined> => {
+    const params = new URLSearchParams({ type, fileID: fileID.toString() });
+    const url = await apiURL("/files/data/preview");
+    const res = await fetch(`${url}?${params.toString()}`, {
+        headers: await authenticatedRequestHeaders(),
+    });
+    if (res.status == 404) return undefined;
+    ensureOk(res);
+    return z.object({ url: z.string() }).parse(await res.json()).url;
+};
diff --git a/web/packages/gallery/services/video.ts b/web/packages/gallery/services/video.ts
index a20538345e..a0be8b45ed 100644
--- a/web/packages/gallery/services/video.ts
+++ b/web/packages/gallery/services/video.ts
@@ -6,7 +6,7 @@ import { FileType } from "@/media/file-type";
 import { gunzip } from "@/new/photos/utils/gzip";
 import { ensurePrecondition } from "@/utils/ensure";
 import { z } from "zod";
-import { fetchFileData } from "./file-data";
+import { fetchFileData, fetchFilePreviewData } from "./file-data";
 
 /**
  * Return a HLS playlist that can be used to stream playback of thne given video
@@ -17,26 +17,7 @@ import { fetchFileData } from "./file-data";
  * @returns The HLS playlist as a string, or `undefined` if there is no video
  * preview associated with the given file.
  *
- * [Note: Video playlist and preview]
- *
- * In museum's ontology, there is a distinction between two concepts:
- *
- * S3 metadata is the data that museum uploads (on behalf of the client):
- * - ML data.
- * - Preview video playlist.
- *
- * S3 file data is the data that client uploads:
- * - Preview video itself.
- * - Additional preview images.
- *
- * Because of this separation, there are separate code paths dealing with the
- * two parts we need to play streaming video:
- *
- * - The encrypted HLS playlist (which is stored as file data of type
- *   "vid_preview"),
- *
- * - And the encrypted video chunks that it (the playlist) refers to (which are
- *   stored as file preview data of type "vid_preview").
+ * See: [Note: Video playlist and preview]
  */
 export const hlsPlaylistForFile = async (file: EnteFile) => {
     ensurePrecondition(file.metadata.fileType == FileType.video);
@@ -44,11 +25,17 @@ export const hlsPlaylistForFile = async (file: EnteFile) => {
     const playlistFileData = await fetchFileData("vid_preview", file.id);
     if (!playlistFileData) return undefined;
 
+    const videoURL = await fetchFilePreviewData("vid_preview", file.id);
+    if (!videoURL) return undefined;
+
     // See: [Note: strict mode migration]
     //
     // eslint-disable-next-line @typescript-eslint/ban-ts-comment
     // @ts-ignore
-    const { playlist } = await decryptPlaylistJSON(playlistFileData, file);
+    const { playlist: playlistTemplate } = await decryptPlaylistJSON(
+        playlistFileData,
+        file,
+    );
 
     // [Note: HLS playlist format]
     //
@@ -102,6 +89,7 @@ export const hlsPlaylistForFile = async (file: EnteFile) => {
     //   (AES-128 for us), URI and IV attributes. The URI attribute value is a
     //   quoted string containing a URI that specfies how to obtain the key.
 
+    const playlist = playlistTemplate.replaceAll("output.ts", videoURL);
     log.debug(() => ["hlsPlaylistForFile", playlist]);
     return file.id;
 };