perf: play animation previews on hover instead of autoplay

[Coder-soft]

Problem

Every resource card in the Animations category mounted an autoplaying <video> as soon as it scrolled into view. With many cards visible at once, the browser streamed and decoded all of them simultaneously, causing heavy CPU/network lag while scrolling. The community Showcase grid had the same behavior.

Change

• Add HoverVideo, which renders the video's first frame as a thumbnail using preload="metadata" plus a #t=0.1 media fragment. It only calls play() while the pointer is over the card, and pauses + resets on leave (and when the tab is hidden).
• Use HoverVideo for animation cards in ResourceCard (behind the existing placeholder icon).
• Use HoverVideo for videos in the Showcase grid; the lightbox still autoplays on demand.

Notes

Animations currently have no stored thumbnail_url/image_url (public/resources/animations.json), so the thumbnail is the video's own first frame rather than a separate image. This removes the per-card full-video decode in favor of a metadata-only fetch per in-view card.

Verification

• tsc --noEmit reports no errors in the changed files.
• eslint clean on the changed files.

Summary by CodeRabbit

• New Features
  • Video previews in resource and showcase cards now display a thumbnail, play on hover, and pause when the page is hidden.

[Coder-soft]

/oc review

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Review configuration:

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: CHILL
• Plan: Advanced
• Run ID: 8965acc8-7c67-436f-bc14-3f444d1f2157

📥 Commits

Reviewing files that changed from the base of the PR and between c2eaa72 and e06a964.

📒 Files selected for processing (3)

• src/components/HoverVideo.tsx
• src/components/resources/ResourceCard.tsx
• src/pages/Showcase.tsx

📝 Walkthrough

Walkthrough

A shared HoverVideo component displays a video thumbnail and plays the video on hover. Resource cards and showcase cards use it for their video previews.

Changes

Hover Video Previews

Layer / File(s)	Summary
Thumbnail and hover playback src/components/HoverVideo.tsx	HoverVideo seeks to a configurable thumbnail time and displays after video data loads or seeking completes. It plays on hover, pauses on mouse leave or when the document is hidden, and renders nothing after playback or media errors.
Resource and showcase previews src/components/resources/ResourceCard.tsx, src/pages/Showcase.tsx	Both preview surfaces use HoverVideo instead of inline autoplaying video. ResourceCard retains its placeholder, and the showcase overlay ignores pointer events.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix

Sequence Diagram(s)

sequenceDiagram
  participant Pointer
  participant HoverVideo
  participant HTMLVideoElement
  participant Document
  HTMLVideoElement->>HoverVideo: video data loads
  HoverVideo->>HTMLVideoElement: seek to thumbnail time
  Pointer->>HoverVideo: pointer enters
  HoverVideo->>HTMLVideoElement: play video
  Pointer->>HoverVideo: pointer leaves
  HoverVideo->>HTMLVideoElement: pause and seek to thumbnail time
  Document->>HoverVideo: document becomes hidden
  HoverVideo->>HTMLVideoElement: pause video

Loading

Merge Risk: 🔵 Low · up to c2eaa

A quick hover and pointer leave can make a video preview disappear until the card remounts. The impact is localized, but playback interruptions should be handled before merge if preview reliability is required.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: animation previews now play on hover instead of autoplaying.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 3…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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_{A rabbit found a screen that gleamed
A thumbnail waited, softly beamed
A hover brought the frames to play
A hidden tab would pause the day
The rabbit hopped through previews bright}

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[creatorcluster]

/oc review

[opencode-agent]

Code Review — PR #95: Hover-play animation previews

Solid direction: replacing per-card autoplay with on-demand playback is the right fix, and the pointer-events-none addition on the Showcase overlay (src/pages/Showcase.tsx:64) is a necessary catch — without it the overlay would swallow mouseenter and the preview would never start. A few issues though.

High — play() rejection permanently kills the preview

src/components/HoverVideo.tsx:34

void video.play().catch(() => setHasError(true));

play() rejects with AbortError whenever a pending play is interrupted by a pause(). That is exactly what happens on a quick hover-in/hover-out: the mouseleave effect calls video.pause() (:36) while play() is still pending, the promise rejects, hasError becomes true, and if (hasError) return null (:55) unmounts the video — so the thumbnail disappears instead of showing the first frame. Rapidly sweeping the mouse across a grid will reliably blank previews. Filter the error:

void video.play().catch((err: DOMException) => {
  if (err.name !== "AbortError") setHasError(true);
});

Medium — touch/keyboard users get no preview at all

onMouseEnter/onMouseLeave (:83-84) don't fire on touch. On mobile, animation cards and Showcase videos now render only a static first frame (previously they autoplayed), and tapping a Showcase video opens the lightbox instead. Animation videos are the one category where a still frame is a poor substitute. Consider onPointerEnter/onPointerLeave (pen + touch) plus playing on onFocus for keyboard, or a tap-to-play affordance.

Medium — "metadata-only" is not quite accurate

Setting video.currentTime = thumbnailTime (:38, :78) forces a seek, which issues a media range request per in-view card, not just a metadata fetch. It's still much cheaper than full autoplay, but on a long Animations grid this is still N concurrent range requests. Mounting only on pointer enter (rather than only isInView) or using a rootMargin gate would reduce the steady-state load further.

Low

• src/components/HoverVideo.tsx:26: isReady/hasError are not reset when src changes. React.memo means a changed src reuses state, so a new source can briefly render at opacity-100 before load. Reset via an effect keyed on src (or key the element).
• src/components/HoverVideo.tsx:74-82: the onLoadedMetadata seek duplicates the effect's currentTime assignment; one path is enough.
• src/pages/Showcase.tsx:25: VideoPlayer is imported but never used. Pre-existing, but this file is touched and @typescript-eslint/no-unused-vars is disabled so lint won't catch it.
• poster prop is unused by both callers; if resource.image_url is ever populated for animations, wiring it in would avoid the seek-to-first-frame entirely.

Note

I couldn't execute the claimed verification — node_modules isn't installed in this checkout, so tsc --noEmit and eslint were not re-run here. Based on the config, eslint should pass (unused-vars is off).

No blocking correctness issue beyond the AbortError handling, which I'd fix before merge.

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Actionable comments posted: 1

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Inline comments:
Review comments at @src/components/HoverVideo.tsx:
- Line 34: Update the play() rejection handler in HoverVideo to ignore
AbortError from interrupted playback requests while continuing to set hasError
for all other playback failures.

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ℹ️ Review info

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• Configuration used: Organization UI
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📥 Commits

Reviewing files that changed from the base of the PR and between 85fb3ca and c2eaa72.

📒 Files selected for processing (3)

• src/components/HoverVideo.tsx
• src/components/resources/ResourceCard.tsx
• src/pages/Showcase.tsx

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[Coder-soft]

Thanks — addressed in e06a964:

High — play() AbortError: filtered. play() rejections now only set hasError when err.name !== "AbortError", so a quick hover in/out no longer unmounts the preview (src/components/HoverVideo.tsx:52).

Medium — touch/keyboard: HoverVideo now uses onPointerEnter/onPointerLeave (mouse + pen), onFocus/onBlur for keyboard via a focusable prop, and an opt-in tapToPlay prop for touch. Animation cards pass focusable + tapToPlay; Showcase keeps tap → lightbox (which autoplays).

Medium — request volume: preview mount is now debounced 150ms after entering the viewport and unmounts when out of view, so fast scrolling no longer fires a burst of range requests (ResourceCard.tsx:52-63). The first-frame seek still issues one range request per in-view card, which is the cost of showing a real thumbnail (animations have no stored thumbnail).

Low:

• isReady/hasError/isActive reset on src change.
• Seek de-duplicated into a single seekToThumbnail callback used by both the effect and onLoadedMetadata.
• Removed the unused VideoPlayer import from Showcase.tsx.
• Wired the poster prop to resource.image_url so a real poster will skip the seek once animations have one.

tsc --noEmit and eslint are clean on the three changed files.