Files
siftlode/frontend/src/components/VirtualFeed.tsx
T
peter 540822d2b0 perf(ui): a next-page fetch joins the one in flight instead of sending the cursor again
react-query's fetchNextPage cancels a next page still loading and sends it again by default.
Our requests ignore the abort signal, so the server ran both: the feed's read-ahead effect
re-runs on scroll frames before isFetchingNextPage reaches it, and on prod every feed page
went out 2-3 times (a 0.8 s title sort queued to 2.3 s). Every call now passes NEXT_PAGE
({cancelRefetch: false}), lint-enforced, with a contract test.
2026-10-02 20:46:30 +02:00

93 lines
3.7 KiB
TypeScript

import type { Video, VideoStatus } from "../lib/api";
import { FEED_VIEW_SPEC, type FeedView } from "../lib/feedView";
import type { NEXT_PAGE } from "../lib/nextPage";
import VideoCard from "./VideoCard";
import { VideoMenu } from "./VideoMenu";
import { useContextMenu } from "./ui/useContextMenu";
import VirtualGrid from "./ui/VirtualGrid";
// Estimated row heights before measurement; real heights are measured per-row so these only affect
// the very first paint and the scrollbar's initial guess. Taken from measuring each mode in the
// browser rather than guessed — a bad estimate makes the scrollbar jump as you scroll in.
// RE-MEASURE these when a mode's layout changes: they have gone stale twice already, most recently
// when the E28 C1 action row moved onto the card's picture (cards 340 -> 262, small 257 -> 226).
// The card figures are the roughest of the set by nature — a card's height follows its column width
// (262 measured at 4 columns in a 1268px window), so no single constant is right for every window.
const ROW_EST: Record<FeedView, number> = {
cards: 262,
cardsSmall: 226,
rows: 117,
rowsCompact: 46,
tiles: 138,
};
export interface VirtualFeedProps {
items: Video[];
view: FeedView;
onState: (id: string, status: VideoStatus) => void;
onToggleSave: (id: string, saved: boolean) => void;
onResetState: (id: string) => void;
onOpen: (v: Video, startAt?: number | null) => void;
hasNextPage: boolean;
isFetchingNextPage: boolean;
fetchNextPage: (options: typeof NEXT_PAGE) => unknown;
}
// The feed's videos on the shared VirtualGrid engine — this wrapper only maps a FeedView to the
// grid's layout spec and renders a VideoCard per item. All the virtualization mechanics (measure,
// chunk, place, infinite-scroll) live in VirtualGrid.
export default function VirtualFeed({
items,
view,
onState,
onToggleSave,
onResetState,
onOpen,
hasNextPage,
isFetchingNextPage,
fetchNextPage,
}: VirtualFeedProps) {
const { minCol, colMaxWidth, maxCols, thumb } = FEED_VIEW_SPEC[view];
// The card menu (the video's whole action list, E28 C1) lives HERE rather than in each of the
// feed's callers: this is the list, and `useContextMenu`'s contract is one menu per list. Mounting
// it at this level is also what gives the channel page the menu for free — it renders
// `<Feed channelScoped>`, so it is the same component all the way down.
const menu = useContextMenu<Video>();
const openId = menu.open ? menu.target?.id : undefined;
return (
<>
<VirtualGrid
items={items}
getKey={(v) => v.id}
minCol={minCol}
colMaxWidth={colMaxWidth}
maxCols={maxCols}
rowEst={ROW_EST[view]}
hasNextPage={hasNextPage}
isFetchingNextPage={isFetchingNextPage}
fetchNextPage={fetchNextPage}
keyboardNav
renderItem={(v, itemWidth, index) => (
<VideoCard
video={v}
view={view}
navIndex={index}
// Only the one-line row (thumb:false) reads its own width — it stands columns down as it
// narrows. Everything else takes a stable 0, so a resize (which changes itemWidth every
// frame) doesn't blow past VideoCard's memo for views that wouldn't do anything with it.
width={thumb ? 0 : itemWidth}
onState={onState}
onToggleSave={onToggleSave}
onOpen={onOpen}
menuProps={menu.triggerProps}
menuButtonProps={menu.buttonProps}
// A boolean per card, not the open id: only the two cards whose answer changes re-render.
menuOpen={openId === v.id}
/>
)}
/>
<VideoMenu menu={menu} handlers={{ onState, onToggleSave, onResetState, onOpen }} />
</>
);
}