From 2ea05acb5b014b165a852ff4cca73d0a3d89e3fa Mon Sep 17 00:00:00 2001
From: Ajay <dev@ajay.app>
Date: Mon, 8 Jan 2024 11:30:45 -0500
Subject: [PATCH] Fallback to autogenerated for random thumbnails instead of
 local render

Should prevent playback issues on unpopular videos

Also fix falling back on certain errors
---
 src/dataFetching.ts                 | 15 ++++++++----
 src/thumbnails/thumbnailData.ts     |  3 +++
 src/thumbnails/thumbnailRenderer.ts | 36 +++++++++++++++++++++++------
 3 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/src/dataFetching.ts b/src/dataFetching.ts
index c5fc5a8..ec8ebec 100644
--- a/src/dataFetching.ts
+++ b/src/dataFetching.ts
@@ -1,5 +1,5 @@
 import { VideoID, getVideoID } from "../maze-utils/src/video";
-import { ThumbnailResult, ThumbnailSubmission, fetchVideoMetadata } from "./thumbnails/thumbnailData";
+import { ThumbnailSubmission, ThumbnailWithRandomTimeResult, fetchVideoMetadata } from "./thumbnails/thumbnailData";
 import { TitleResult, TitleSubmission } from "./titles/titleData";
 import { FetchResponse, sendRealRequestToCustomServer } from "../maze-utils/src/background-request-proxy";
 import { BrandingLocation, BrandingResult, updateBrandingForVideo } from "./videoBranding/videoBranding";
@@ -36,14 +36,15 @@ const activeRequests: Record<VideoID, Promise<Record<VideoID, BrandingResult> |
 const activeThumbnailCacheRequests: Record<VideoID, ActiveThumbnailCacheRequestInfo> = {};
 
 export async function getVideoThumbnailIncludingUnsubmitted(videoID: VideoID, brandingLocation?: BrandingLocation,
-        returnRandomTime = true): Promise<ThumbnailResult | null> {
+        returnRandomTime = true): Promise<ThumbnailWithRandomTimeResult | null> {
     const unsubmitted = Config.local!.unsubmitted[videoID]?.thumbnails?.find(t => t.selected);
     if (unsubmitted) {
         return {
             ...unsubmitted,
             votes: 0,
             locked: false,
-            UUID: generateUserID() as BrandingUUID
+            UUID: generateUserID() as BrandingUUID,
+            isRandomTime: false
         };
     }
 
@@ -59,7 +60,8 @@ export async function getVideoThumbnailIncludingUnsubmitted(videoID: VideoID, br
                     votes: 0,
                     locked: false,
                     timestamp: timestamp,
-                    original: false
+                    original: false,
+                    isRandomTime: true
                 };
             } else {
                 return null;
@@ -68,7 +70,10 @@ export async function getVideoThumbnailIncludingUnsubmitted(videoID: VideoID, br
             return null;
         }
     } else {
-        return result;
+        return {
+            ...result,
+            isRandomTime: false
+        };
     }
 }
 
diff --git a/src/thumbnails/thumbnailData.ts b/src/thumbnails/thumbnailData.ts
index 9010d61..294f7df 100644
--- a/src/thumbnails/thumbnailData.ts
+++ b/src/thumbnails/thumbnailData.ts
@@ -23,6 +23,9 @@ export type OriginalThumbnailSubmission = {
 export type OriginalThumbnailResult = PartialThumbnailResult & OriginalThumbnailSubmission;
 
 export type ThumbnailResult = CustomThumbnailResult | OriginalThumbnailResult;
+export type ThumbnailWithRandomTimeResult = ThumbnailResult & {
+    isRandomTime: boolean;
+};
 export type ThumbnailSubmission = CustomThumbnailSubmission | OriginalThumbnailSubmission;
 
 export interface Format {
diff --git a/src/thumbnails/thumbnailRenderer.ts b/src/thumbnails/thumbnailRenderer.ts
index c21c91a..94ae43b 100644
--- a/src/thumbnails/thumbnailRenderer.ts
+++ b/src/thumbnails/thumbnailRenderer.ts
@@ -57,15 +57,29 @@ function addStopRenderingCallback(videoID: VideoID, callback: (error?: string) =
     thumbnailRendererControls[videoID].push(callback);
 }
 
+export class ThumbnailNotInCacheError extends Error {
+    constructor(videoID: VideoID) {
+        super(`Thumbnail not found in cache for ${videoID}`);
+    }
+}
+
 export async function renderThumbnail(videoID: VideoID, width: number,
-    height: number, saveVideo: boolean, timestamp: number): Promise<RenderedThumbnailVideo | null> {
+    height: number, saveVideo: boolean, timestamp: number, onlyFromThumbnailCache = false): Promise<RenderedThumbnailVideo | null> {
 
     const startTime = performance.now();
 
+    if (onlyFromThumbnailCache) {
+        await waitForThumbnailCache(videoID);
+    }
+
     let bestVideoData = await findBestVideo(videoID, width, height, timestamp);
     if (bestVideoData.renderedThumbnail) {
         return bestVideoData.renderedThumbnail;
     }
+
+    if (onlyFromThumbnailCache) {
+        throw new ThumbnailNotInCacheError(videoID);
+    }
     
     await Promise.race([
         waitForSpotInRenderQueue(videoID),
@@ -344,6 +358,7 @@ export async function createThumbnailImageElement(existingElement: HTMLImageElem
     image.style.display = "none";
 
     let timestamp = forcedTimestamp as number;
+    let isRandomTime = false;
     if (timestamp === null) {
         try {
             const thumbnailPromise = getVideoThumbnailIncludingUnsubmitted(videoID, brandingLocation);
@@ -362,6 +377,7 @@ export async function createThumbnailImageElement(existingElement: HTMLImageElem
             const thumbnail = await thumbnailPromise;
             if (thumbnail && !thumbnail.original) {
                 timestamp = thumbnail.timestamp;
+                isRandomTime = thumbnail.isRandomTime;
             } else if (await getThumbnailFallbackOption(videoID) === ThumbnailFallbackOption.AutoGenerated) {
                 return image;
             } else {
@@ -424,14 +440,20 @@ export async function createThumbnailImageElement(existingElement: HTMLImageElem
         ready(image, url, timestamp);
     }
 
-    const activeRender = activeRenders[videoID] ?? renderThumbnail(videoID, width, height, saveVideo, timestamp);
+    const activeRender = activeRenders[videoID] ?? renderThumbnail(videoID, width, height, saveVideo, timestamp, isRandomTime);
     activeRenders[videoID] = activeRender;
     
-    activeRender.then(result).catch(() => {
-        // Try again with lower resolution
-        renderThumbnail(videoID, 0, 0, saveVideo, timestamp).then(result).catch(() => {
-            logError(`Failed to render thumbnail for ${videoID}`);
-        });
+    activeRender.then(result).catch((e) => {
+        if (e instanceof ThumbnailNotInCacheError) {
+            failure();
+        } else {
+            // Try again with lower resolution
+            renderThumbnail(videoID, 0, 0, saveVideo, timestamp, isRandomTime).then(result).catch((e) => {
+                log(`Failed to render thumbnail for ${videoID} due to ${e}`);
+    
+                failure();
+            });
+        }
     });
 
     return image;