"use client"; import { useEffect, useRef, useState, useSyncExternalStore } from "react"; import type { HTMLAttributes, ReactNode } from "react"; export type StatStripItem = { label: string; value: number; format?: Intl.NumberFormatOptions; unit?: string; delta?: number; goodDirection?: "up" | "down"; }; export type StatStripProps = Omit, "children" | "title"> & { stats: StatStripItem[]; title?: ReactNode; period: string; comparisonLabel?: string; locale?: string; countUp?: boolean; duration?: number; reducedMotion?: boolean; }; const motionQuery = "(prefers-reduced-motion: reduce)"; function subscribeMotion(callback: () => void) { const media = window.matchMedia(motionQuery); media.addEventListener?.("change", callback); return () => media.removeEventListener?.("change", callback); } function usePrefersReducedMotion(force?: boolean) { const preferred = useSyncExternalStore(subscribeMotion, () => window.matchMedia(motionQuery).matches, () => false); return force ?? preferred; } function formatValue(value: number, locale: string, stat: StatStripItem) { return new Intl.NumberFormat(locale, stat.format).format(value) + (stat.unit ?? ""); } function formatDelta(delta: number, locale: string) { return new Intl.NumberFormat(locale, { style: "percent", maximumFractionDigits: 1, minimumFractionDigits: 1 }).format(Math.abs(delta)); } export function StatStrip({ stats, title, period, comparisonLabel = "vs previous period", locale = "en-US", countUp = false, duration = 900, reducedMotion, className = "", ...props }: StatStripProps) { const reduce = usePrefersReducedMotion(reducedMotion); const root = useRef(null); const [progress, setProgress] = useState(countUp ? 0 : 1); const played = useRef(false); useEffect(() => { const element = root.current; if (played.current) return; if (!countUp || reduce || !element || typeof IntersectionObserver === "undefined") { setProgress(1); return; } let frame = 0; const observer = new IntersectionObserver( (entries) => { if (!entries.some((entry) => entry.isIntersecting) || played.current) return; played.current = true; observer.disconnect(); const start = performance.now(); const tick = (now: number) => { const t = Math.min(1, (now - start) / duration); setProgress(1 - Math.pow(1 - t, 3)); if (t < 1) frame = window.requestAnimationFrame(tick); }; setProgress(0); frame = window.requestAnimationFrame(tick); }, { threshold: 0.4 }, ); observer.observe(element); return () => { observer.disconnect(); window.cancelAnimationFrame(frame); if (played.current) setProgress(1); }; }, [countUp, duration, reduce]); return (

{title ? (

{title}

{period}

) : null}

{stat.label}: {finalText}; {direction !== "flat" ? ( ) : null} {(direction === "flat" ? "No change " : (direction === "up" ? "Up " : "Down ") + formatDelta(delta, locale) + " ") + comparisonLabel}

{!title ?

{period}

: null}

); }

API usage

API usage