File size: 4,298 Bytes
d02c2a6 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | 'use client';
import { useEffect, useRef, useState } from 'react';
import { apiClient } from '@/utils/api';
// Module-level batcher: many cards mount at once when the virtualized grid scrolls;
// instead of N HTTP requests, queue paths and flush them as a single batch.
type Resolver = { resolve: (caption: string) => void; reject: (err: unknown) => void };
const pending = new Map<string, Resolver[]>();
const cache = new Map<string, string>();
let flushTimer: ReturnType<typeof setTimeout> | null = null;
const FLUSH_DELAY_MS = 30;
const MAX_BATCH = 200;
function scheduleFlush() {
if (flushTimer) return;
flushTimer = setTimeout(flush, FLUSH_DELAY_MS);
}
async function flush() {
flushTimer = null;
if (pending.size === 0) return;
// Drain up to MAX_BATCH paths; if more arrived, reschedule.
const paths: string[] = [];
for (const path of pending.keys()) {
paths.push(path);
if (paths.length >= MAX_BATCH) break;
}
const batchResolvers = paths.map(p => ({ path: p, resolvers: pending.get(p)! }));
for (const p of paths) pending.delete(p);
try {
const res = await apiClient.post('/api/caption/getBatch', { imgPaths: paths });
const captions: Record<string, string> = res.data?.captions ?? {};
for (const { path, resolvers } of batchResolvers) {
const value = captions[path] ?? '';
cache.set(path, value);
for (const r of resolvers) r.resolve(value);
}
} catch (err) {
for (const { resolvers } of batchResolvers) {
for (const r of resolvers) r.reject(err);
}
}
if (pending.size > 0) scheduleFlush();
}
function requestCaption(path: string, signal?: AbortSignal): Promise<string> {
return new Promise((resolve, reject) => {
if (signal?.aborted) {
reject(new DOMException('Aborted', 'AbortError'));
return;
}
const resolver: Resolver = { resolve, reject };
const list = pending.get(path);
if (list) {
list.push(resolver);
} else {
pending.set(path, [resolver]);
}
if (signal) {
const onAbort = () => {
// Remove this resolver from the pending batch. If no other card is
// still waiting on the same path, drop the path entirely so the next
// batch doesn't include it.
const arr = pending.get(path);
if (arr) {
const idx = arr.indexOf(resolver);
if (idx >= 0) arr.splice(idx, 1);
if (arr.length === 0) pending.delete(path);
}
reject(new DOMException('Aborted', 'AbortError'));
};
signal.addEventListener('abort', onAbort, { once: true });
}
scheduleFlush();
});
}
export function invalidateCaption(path: string) {
cache.delete(path);
}
export function setCachedCaption(path: string, caption: string) {
cache.set(path, caption);
}
// Fetches caption for a path, using the module-level batcher + cache.
// `refreshKey` busts the cache (e.g. after external edits or auto-captioning poll).
export default function useCaptionBatch(imgPath: string | null, refreshKey: number = 0) {
const [caption, setCaption] = useState<string>(() => (imgPath ? (cache.get(imgPath) ?? '') : ''));
const [isLoaded, setIsLoaded] = useState<boolean>(() => Boolean(imgPath && cache.has(imgPath)));
const lastPathRef = useRef<string | null>(null);
useEffect(() => {
if (!imgPath) {
setCaption('');
setIsLoaded(false);
return;
}
if (refreshKey > 0) invalidateCaption(imgPath);
const cached = cache.get(imgPath);
if (cached !== undefined) {
setCaption(cached);
setIsLoaded(true);
lastPathRef.current = imgPath;
return;
}
let cancelled = false;
const controller = new AbortController();
lastPathRef.current = imgPath;
setIsLoaded(false);
requestCaption(imgPath, controller.signal)
.then(value => {
if (cancelled || lastPathRef.current !== imgPath) return;
setCaption(value);
setIsLoaded(true);
})
.catch(err => {
if (err?.name === 'AbortError' || cancelled) return;
console.error('Error fetching caption:', err);
setIsLoaded(true);
});
return () => {
cancelled = true;
controller.abort();
};
}, [imgPath, refreshKey]);
return { caption, isLoaded, setCaption };
}
|