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hantui

Web3: DeFi & Tradingv0.2.0

Live Price Ticker

A marquee of pairs with rolling digits and tick flashes.

Installation

CLI

npx shadcn@latest add https://hantui-theta.vercel.app/r/price-ticker.json

Manual

  1. Install the dependencies

    npm install clsx lucide-react motion tailwind-merge viem

  2. Add the shared helpers

    Components use cn() from lib/utils.ts and the motion tokens below. See Installation if you have not set them up yet.

    lib/color.ts
    export type Vec3 = [r: number, g: number, b: number];

/**
 * Parses #rgb, #rrggbb or #rrggbbaa (alpha is ignored) into 0–255 channels.
 * Anything else falls back to black, so a typo never crashes a shader.
 */
export function hexToRgb(hex: string): Vec3 {
  let value = hex.trim().replace(/^#/, "");
  if (value.length === 3 || value.length === 4) value = [...value.slice(0, 3)].map((c) => c + c).join("");
  if (!/^[\da-f]{6}([\da-f]{2})?$/i.test(value)) return [0, 0, 0];
  const n = Number.parseInt(value.slice(0, 6), 16);
  return [(n >> 16) & 255, (n >> 8) & 255, n & 255];
}

/** Hex color as a normalized vec3 (each channel 0–1) for shader uniforms. */
export function hexToVec3(hex: string): Vec3 {
  const [r, g, b] = hexToRgb(hex);
  return [r / 255, g / 255, b / 255];
}

/**
 * Any CSS color the browser understands (hex, rgb(), oklch(), color-mix() or a variable such as
 * `var(--primary)`) as 0–255 channels, computed in the context of `element` so theme variables
 * resolve. Hex takes a fast path; everything else is computed once per call, so cache the result
 * instead of calling this every frame. Browser only; unreadable values fall back to black.
 */
export function cssColorToRgb(color: string, element: Element): Vec3 {
  const value = color.trim();
  if (/^#[\da-f]{3,8}$/i.test(value)) return hexToRgb(value);
  // Children of a canvas still get computed styles, but a regular parent is the safer host.
  const host = element instanceof HTMLCanvasElement ? (element.parentElement ?? document.body) : element;
  const probe = document.createElement("span");
  probe.style.cssText = "position:absolute;width:0;height:0;overflow:hidden;visibility:hidden";
  probe.style.color = value;
  host.appendChild(probe);
  const computed = getComputedStyle(probe).color;
  probe.remove();
  // A 1×1 canvas turns any computed color space (oklch, color(srgb …)) into sRGB bytes.
  const ctx = document.createElement("canvas").getContext("2d", { willReadFrequently: true });
  if (!ctx) return [0, 0, 0];
  ctx.fillStyle = "#000";
  ctx.fillStyle = computed;
  ctx.fillRect(0, 0, 1, 1);
  const [r, g, b] = ctx.getImageData(0, 0, 1, 1).data;
  return [r, g, b];
}

/**
 * Calls `onChange` when the page theme may have changed: a class or data-theme change on <html> or
 * <body> (shadcn's `.dark`, next-themes, a data-theme switch) or a change of the OS color scheme.
 * Resolved colors are cached, so re-resolve them here. Browser only; returns the unsubscribe.
 */
export function observeTheme(onChange: () => void): () => void {
  const observer = new MutationObserver(onChange);
  const options = { attributes: true, attributeFilter: ["class", "data-theme"] };
  observer.observe(document.documentElement, options);
  if (document.body) observer.observe(document.body, options);
  const scheme = window.matchMedia("(prefers-color-scheme: dark)");
  scheme.addEventListener("change", onChange);
  return () => {
    observer.disconnect();
    scheme.removeEventListener("change", onChange);
  };
}

/** `cssColorToRgb` as a normalized vec3 (each channel 0–1) for shader uniforms. */
export function cssColorToVec3(color: string, element: Element): Vec3 {
  const [r, g, b] = cssColorToRgb(color, element);
  return [r / 255, g / 255, b / 255];
}

const toLinear = (c: number) => (c <= 0.04045 ? c / 12.92 : ((c + 0.055) / 1.055) ** 2.4);
const toGamma = (c: number) => (c <= 0.0031308 ? 12.92 * c : 1.055 * c ** (1 / 2.4) - 0.055);

/** 0–255 sRGB to OKLCH: lightness 0–1, chroma, hue in radians. */
export function rgbToOklch([r, g, b]: Vec3): Vec3 {
  const [lr, lg, lb] = [r, g, b].map((v) => toLinear(v / 255));
  const l = Math.cbrt(0.4122214708 * lr + 0.5363325363 * lg + 0.0514459929 * lb);
  const m = Math.cbrt(0.2119034982 * lr + 0.6806995451 * lg + 0.1073969566 * lb);
  const s = Math.cbrt(0.0883024619 * lr + 0.2817188376 * lg + 0.6299787005 * lb);
  const L = 0.2104542553 * l + 0.793617785 * m - 0.0040720468 * s;
  const A = 1.9779984951 * l - 2.428592205 * m + 0.4505937099 * s;
  const B = 0.0259040371 * l + 0.7827717662 * m - 0.808675766 * s;
  return [L, Math.hypot(A, B), Math.atan2(B, A)];
}

/** OKLCH back to 0–255 sRGB, clamped into gamut. */
export function oklchToRgb([L, C, h]: Vec3): Vec3 {
  const A = C * Math.cos(h);
  const B = C * Math.sin(h);
  const l = (L + 0.3963377774 * A + 0.2158037573 * B) ** 3;
  const m = (L - 0.1055613458 * A - 0.0638541728 * B) ** 3;
  const s = (L - 0.0894841775 * A - 1.291485548 * B) ** 3;
  const rgb = [4.0767416621 * l - 3.3077115913 * m + 0.2309699292 * s, -1.2684380046 * l + 2.6097574011 * m - 0.3413193965 * s, -0.0041960863 * l - 0.7034186147 * m + 1.707614701 * s];
  return rgb.map((v) => Math.round(Math.min(1, Math.max(0, toGamma(Math.min(1, Math.max(0, v))))) * 255)) as Vec3;
}

/**
 * Mixes two 0–255 colors in OKLCH, taking the short way around the hue circle, so midpoints keep
 * their chroma instead of turning muddy the way an RGB mix does.
 */
export function mixOklch(a: Vec3, b: Vec3, t: number): Vec3 {
  const [L1, C1, h1] = rgbToOklch(a);
  const [L2, C2, h2] = rgbToOklch(b);
  // A near-gray end has no meaningful hue: borrow the other end's.
  const ha = C1 < 0.02 ? h2 : h1;
  const hb = C2 < 0.02 ? h1 : h2;
  let dh = hb - ha;
  if (dh > Math.PI) dh -= Math.PI * 2;
  if (dh < -Math.PI) dh += Math.PI * 2;
  return oklchToRgb([L1 + (L2 - L1) * t, C1 + (C2 - C1) * t, ha + dh * t]);
}
    lib/web3/format.ts
    import { formatUnits, getAddress, isAddress, parseUnits } from "viem";

/**
 * Formatting for on-chain values. Amounts are always `bigint` plus `decimals`: nothing here
 * converts a balance to a float, so large or precise values never lose digits.
 */

/** Decimals used for USD values and prices across the web3 components (like Chainlink feeds). */
export const USD_DECIMALS = 8;

const COMPACT_UNITS = [
  { suffix: "T", exponent: 12 },
  { suffix: "B", exponent: 9 },
  { suffix: "M", exponent: 6 },
  { suffix: "K", exponent: 3 },
] as const;

function groupThousands(integer: string) {
  return integer.replace(/\B(?=(\d{3})+(?!\d))/g, ",");
}

function compact(value: bigint, decimals: number): string | null {
  const base = BigInt(10) ** BigInt(decimals);
  for (const { suffix, exponent } of COMPACT_UNITS) {
    const unit = base * BigInt(10) ** BigInt(exponent);
    if (value < unit) continue;
    const tenths = (value * BigInt(10)) / unit;
    const whole = tenths / BigInt(10);
    const fraction = tenths % BigInt(10);
    return `${groupThousands(whole.toString())}${fraction && whole < BigInt(100) ? `.${fraction}` : ""}${suffix}`;
  }
  return null;
}

export interface FormatAmountOptions {
  /** Most fraction digits shown; extra digits are cut, never rounded up. @default 4 */
  maxFractionDigits?: number;
  /** Fraction digits always shown (padded with zeros). @default 0 */
  minFractionDigits?: number;
  /** Abbreviate values of 1,000 and up: 1.2K, 3.4M, 5B. @default false */
  compact?: boolean;
  /** Prefix positive values with "+". @default false */
  signed?: boolean;
}

/**
 * Formats a token amount: `formatAmount(parseUnits("1.23456789", 18), 18)` → "1.2345".
 * Digits past `maxFractionDigits` are truncated so a balance is never overstated, and a tiny
 * non-zero amount shows as "<0.0001" instead of "0".
 */
export function formatAmount(value: bigint, decimals: number, options: FormatAmountOptions = {}) {
  const { maxFractionDigits = 4, minFractionDigits = 0, compact: useCompact = false, signed = false } = options;
  const negative = value < BigInt(0);
  const abs = negative ? -value : value;
  const sign = negative ? "-" : signed && abs > BigInt(0) ? "+" : "";

  const short = useCompact ? compact(abs, decimals) : null;
  if (short) return sign + short;

  const [integer, fraction = ""] = formatUnits(abs, decimals).split(".");
  let digits = fraction.slice(0, maxFractionDigits).replace(/0+$/, "");
  if (digits.length < minFractionDigits) digits = digits.padEnd(minFractionDigits, "0");

  if (abs > BigInt(0) && integer === "0" && !/[1-9]/.test(digits)) {
    return `${sign}<0.${"0".repeat(Math.max(0, maxFractionDigits - 1))}1`;
  }
  return `${sign}${groupThousands(integer)}${digits ? `.${digits}` : ""}`;
}

/** USD value of a token amount, as a bigint with `USD_DECIMALS` decimals. `price` uses the same decimals. */
export function toUsd(amount: bigint, tokenDecimals: number, price: bigint) {
  return (amount * price) / BigInt(10) ** BigInt(tokenDecimals);
}

/** Formats a USD bigint (default `USD_DECIMALS`): "$1,234.56", or "$1.2M" with `compact`. */
export function formatUsd(value: bigint, decimals = USD_DECIMALS, options: Omit<FormatAmountOptions, "maxFractionDigits"> = {}) {
  const { compact: useCompact = false, signed = false } = options;
  const negative = value < BigInt(0);
  const abs = negative ? -value : value;
  const sign = negative ? "-" : signed && abs > BigInt(0) ? "+" : "";
  // Under a cent, keep up to 6 significant fraction digits so token prices like $0.000042 stay readable.
  const tiny = abs > BigInt(0) && abs < BigInt(10) ** BigInt(Math.max(0, decimals - 2));
  const body = formatAmount(abs, decimals, {
    compact: useCompact,
    maxFractionDigits: tiny ? Math.min(decimals, 8) : 2,
    minFractionDigits: tiny ? 0 : 2,
  });
  return `${sign}$${body}`;
}

/** Formats a ratio as a percentage: `formatPercent(0.0123)` → "1.23%". */
export function formatPercent(ratio: number, options: { fractionDigits?: number; signed?: boolean } = {}) {
  const { fractionDigits = 2, signed = false } = options;
  if (!Number.isFinite(ratio)) return "—";
  const text = `${(Math.abs(ratio) * 100).toFixed(fractionDigits)}%`;
  if (ratio < 0) return `-${text}`;
  return signed && ratio > 0 ? `+${text}` : text;
}

/** Formats basis points (1 bp = 0.01%): `formatBps(BigInt(50))` → "0.5%". */
export function formatBps(bps: bigint | number) {
  const value = BigInt(bps);
  const abs = value < BigInt(0) ? -value : value;
  const fraction = abs % BigInt(100);
  return `${value < BigInt(0) ? "-" : ""}${abs / BigInt(100)}${fraction ? `.${fraction.toString().padStart(2, "0").replace(/0$/, "")}` : ""}%`;
}

/** Compact display for plain counts and non-token numbers: 1200 → "1.2K". */
export function compactNumber(value: number | bigint) {
  return new Intl.NumberFormat("en-US", { notation: "compact", maximumFractionDigits: 1 }).format(value);
}

/** EIP-55 checksummed address, or the input unchanged when it isn't a valid address. */
export function checksumAddress(address: string) {
  return isAddress(address, { strict: false }) ? getAddress(address) : address;
}

/** "0x1234…abcd": checksummed, with `start` characters (including 0x) and `end` characters kept. */
export function truncateAddress(address: string, { start = 6, end = 4 }: { start?: number; end?: number } = {}) {
  const value = checksumAddress(address);
  if (value.length <= start + end + 1) return value;
  return `${value.slice(0, start)}…${value.slice(-end)}`;
}

/**
 * Parses user input into a bigint amount. Accepts digits with one "." (commas are ignored),
 * cuts fraction digits past `decimals`, and returns null for anything that isn't a number.
 */
export function parseAmount(input: string, decimals: number): bigint | null {
  const text = input.replace(/,/g, "").trim();
  if (!/^\d*\.?\d*$/.test(text) || text === "" || text === ".") return null;
  const [integer, fraction = ""] = text.split(".");
  return parseUnits(`${integer || "0"}.${fraction.slice(0, decimals) || "0"}`, decimals);
}

/** A percentage of an amount, in whole percent: `percentOf(balance, 25)`. Rounds down. */
export function percentOf(amount: bigint, percent: number) {
  return (amount * BigInt(Math.round(percent * 100))) / BigInt(10_000);
}
    lib/web3/icons.tsx
    "use client";

import { useId, type ComponentProps } from "react";
import { hexToRgb } from "@/lib/color";
import { cn } from "@/lib/utils";

/**
 * Generated avatars for tokens, chains and accounts. No third-party logos are bundled:
 * pass `iconUrl` (tokens, chains) or `src` (accounts) to show your own artwork.
 */

const PALETTE = ["#6366F1", "#2563EB", "#0EA5E9", "#14B8A6", "#16A34A", "#F59E0B", "#EF4444", "#EC4899", "#8B5CF6", "#64748B"];

function hashString(value: string) {
  let hash = 0x811c9dc5;
  for (const char of value) hash = Math.imul(hash ^ char.charCodeAt(0), 0x01000193);
  return hash >>> 0;
}

/** Text color with enough contrast on a fill (relative luminance threshold). */
function inkFor(fill: string) {
  const [r, g, b] = hexToRgb(fill).map((c) => {
    const s = c / 255;
    return s <= 0.03928 ? s / 12.92 : ((s + 0.055) / 1.055) ** 2.4;
  });
  return 0.2126 * r + 0.7152 * g + 0.0722 * b > 0.45 ? "#09090B" : "#FFFFFF";
}

function Monogram({ text, fill, size, shape, className }: { text: string; fill: string; size: number; shape: "circle" | "squircle"; className?: string }) {
  const letters = text.slice(0, 4);
  const fontSize = letters.length <= 2 ? 13 : letters.length === 3 ? 10 : 8.5;
  return (
    <svg width={size} height={size} viewBox="0 0 32 32" aria-hidden="true" className={cn("shrink-0", className)}>
      {shape === "circle" ? <circle cx="16" cy="16" r="16" fill={fill} /> : <rect width="32" height="32" rx="9" fill={fill} />}
      <text
        x="16"
        y="16"
        dy="0.35em"
        textAnchor="middle"
        fontSize={fontSize}
        fontWeight={700}
        fill={inkFor(fill)}
        style={{ fontFamily: "inherit", letterSpacing: letters.length > 2 ? "-0.02em" : undefined }}
      >
        {letters}
      </text>
    </svg>
  );
}

function ImageIcon({ src, size, rounded, className }: { src: string; size: number; rounded: string; className?: string }) {
  // eslint-disable-next-line @next/next/no-img-element -- consumers pass arbitrary logo URLs
  return <img src={src} alt="" width={size} height={size} className={cn("shrink-0 object-cover", rounded, className)} />;
}

export interface TokenIconProps {
  token: { symbol: string; iconUrl?: string; color?: string };
  /** Pixel size. @default 24 */
  size?: number;
  className?: string;
}

/** A token's logo, or a colored circle with its symbol. Decorative: pair it with visible text. */
export function TokenIcon({ token, size = 24, className }: TokenIconProps) {
  if (token.iconUrl) return <ImageIcon src={token.iconUrl} size={size} rounded="rounded-full" className={className} />;
  const fill = token.color ?? PALETTE[hashString(token.symbol) % PALETTE.length];
  return <Monogram text={token.symbol} fill={fill} size={size} shape="circle" className={className} />;
}

export interface ChainIconProps {
  chain: { name: string; shortName?: string; iconUrl?: string; color?: string };
  /** Pixel size. @default 20 */
  size?: number;
  className?: string;
}

/** A chain's logo, or a rounded square with its initial. Decorative: pair it with visible text. */
export function ChainIcon({ chain, size = 20, className }: ChainIconProps) {
  if (chain.iconUrl) return <ImageIcon src={chain.iconUrl} size={size} rounded="rounded-[28%]" className={className} />;
  const fill = chain.color ?? PALETTE[hashString(chain.name) % PALETTE.length];
  return <Monogram text={(chain.shortName ?? chain.name).charAt(0)} fill={fill} size={size} shape="squircle" className={className} />;
}

export interface WalletIconProps {
  wallet: { name: string; iconUrl?: string; color?: string };
  /** Pixel size. @default 32 */
  size?: number;
  className?: string;
}

/** A wallet's logo, or a rounded square with its initial. Decorative: pair it with visible text. */
export function WalletIcon({ wallet, size = 32, className }: WalletIconProps) {
  if (wallet.iconUrl) return <ImageIcon src={wallet.iconUrl} size={size} rounded="rounded-[28%]" className={className} />;
  const fill = wallet.color ?? PALETTE[hashString(wallet.name) % PALETTE.length];
  return <Monogram text={wallet.name.charAt(0)} fill={fill} size={size} shape="squircle" className={className} />;
}

export interface AddressAvatarProps extends Omit<ComponentProps<"svg">, "children"> {
  address: string;
  /** Pixel size. @default 24 */
  size?: number;
}

/** A deterministic gradient avatar for an address: same address, same avatar, on every device. */
export function AddressAvatar({ address, size = 24, className, ...props }: AddressAvatarProps) {
  const id = useId();
  const hex = address.toLowerCase().replace(/^0x/, "").padEnd(40, "0");
  const byte = (i: number) => Number.parseInt(hex.slice(i * 2, i * 2 + 2), 16) || 0;
  const hue = Math.round((byte(0) / 255) * 360);
  const hue2 = (hue + 40 + Math.round((byte(1) / 255) * 120)) % 360;
  const angle = Math.round((byte(2) / 255) * 360);
  return (
    <svg width={size} height={size} viewBox="0 0 32 32" aria-hidden="true" className={cn("shrink-0 rounded-full", className)} {...props}>
      <defs>
        <linearGradient id={`${id}g`} gradientTransform={`rotate(${angle} 0.5 0.5)`}>
          <stop offset="0" stopColor={`hsl(${hue} 85% 64%)`} />
          <stop offset="1" stopColor={`hsl(${hue2} 80% 52%)`} />
        </linearGradient>
        <clipPath id={`${id}c`}>
          <circle cx="16" cy="16" r="16" />
        </clipPath>
      </defs>
      <g clipPath={`url(#${id}c)`}>
        <rect width="32" height="32" fill={`url(#${id}g)`} />
        <circle cx={6 + (byte(3) % 20)} cy={6 + (byte(4) % 20)} r={6 + (byte(5) % 6)} fill="#fff" opacity="0.32" />
        <circle cx={6 + (byte(6) % 20)} cy={6 + (byte(7) % 20)} r={3 + (byte(8) % 5)} fill="#fff" opacity="0.22" />
      </g>
    </svg>
  );
}
    lib/web3/rolling-value.tsx
    "use client";

import { useEffect, useState } from "react";
import { AnimatePresence, motion, useReducedMotion } from "motion/react";
import { cn } from "@/lib/utils";

const DIGITS = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"];
const REEL = { type: "spring", stiffness: 160, damping: 22, mass: 0.9 } as const;
const MASK = "linear-gradient(to bottom, transparent, #000 22%, #000 78%, transparent)";

function Reel({ digit, reduceMotion }: { digit: number; reduceMotion: boolean }) {
  return (
    <span className="relative inline-block [clip-path:inset(0)]" style={{ maskImage: MASK, WebkitMaskImage: MASK }}>
      <span className="invisible">0</span>
      <motion.span
        className="absolute inset-x-0 top-0 flex flex-col items-center"
        initial={false}
        animate={{ y: `${-digit * 10}%` }}
        transition={reduceMotion ? { duration: 0 } : REEL}
      >
        {DIGITS.map((n) => (
          <span key={n}>{n}</span>
        ))}
      </motion.span>
    </span>
  );
}

export interface RollingValueProps {
  /** Pre-formatted text, e.g. "$1,234.56" or "2.4815". Digits roll; everything else stays put. */
  value: string;
  /**
   * The raw value behind the text (a bigint amount or a number). When it changes, the text
   * flashes green for an increase and red for a decrease.
   */
  trend?: bigint | number;
  /** Flash on increases and decreases. @default true */
  flash?: boolean;
  className?: string;
}

type Flash = { direction: "up" | "down"; key: number };

/**
 * Rolling digits for pre-formatted strings, so bigint amounts animate without ever becoming
 * floats. Uses tabular figures; screen readers get the plain text.
 */
export function RollingValue({ value, trend, flash = true, className }: RollingValueProps) {
  const reduceMotion = useReducedMotion() ?? false;
  const [previous, setPrevious] = useState(trend);
  const [pulse, setPulse] = useState<Flash | null>(null);

  if (trend !== previous) {
    setPrevious(trend);
    if (flash && trend !== undefined && previous !== undefined) {
      setPulse({ direction: trend > previous ? "up" : "down", key: (pulse?.key ?? 0) + 1 });
    }
  }

  useEffect(() => {
    if (!pulse) return;
    const timer = window.setTimeout(() => setPulse(null), 900);
    return () => window.clearTimeout(timer);
  }, [pulse]);

  // Key characters by their distance from the end, so a given place value keeps its reel.
  const chars = [...value];
  return (
    <span
      className={cn(
        "relative inline-flex tabular-nums transition-colors duration-300",
        pulse?.direction === "up" && "text-[color-mix(in_oklab,var(--success)_75%,var(--foreground))]",
        pulse?.direction === "down" && "text-[color-mix(in_oklab,var(--destructive)_80%,var(--foreground))]",
        className,
      )}
    >
      <span className="sr-only">{value}</span>
      <AnimatePresence>
        {pulse && !reduceMotion ? (
          <motion.span
            key={pulse.key}
            aria-hidden="true"
            className={cn(
              "pointer-events-none absolute -inset-x-1 inset-y-0 rounded-[4px]",
              pulse.direction === "up" ? "bg-success/12" : "bg-destructive/12",
            )}
            initial={{ opacity: 1 }}
            animate={{ opacity: 0 }}
            exit={{ opacity: 0 }}
            transition={{ duration: 0.9, ease: "easeOut" }}
          />
        ) : null}
      </AnimatePresence>
      <span aria-hidden="true" className="relative inline-flex select-none">
        {chars.map((char, index) => {
          const key = chars.length - index;
          return /\d/.test(char) ? <Reel key={key} digit={Number(char)} reduceMotion={reduceMotion} /> : <span key={`${key}${char}`}>{char}</span>;
        })}
      </span>
    </span>
  );
}
    lib/web3/types.ts
    /** Shapes the web3 components accept. Your own token and chain objects only need these fields. */

export interface Token {
  symbol: string;
  name?: string;
  /** Token decimals: 18 for ETH, 6 for USDC. Amounts are bigint in these units. */
  decimals: number;
  address?: string;
  /** Logo URL. Without one, a generated avatar (colored circle and symbol) is shown. */
  iconUrl?: string;
  /** Avatar color for the generated icon. Picked from the symbol when omitted. */
  color?: string;
  /** USD price as a bigint with USD_DECIMALS (8) decimals. */
  price?: bigint;
}

export interface Chain {
  id: number;
  name: string;
  shortName?: string;
  iconUrl?: string;
  color?: string;
  /** Block explorer base URL without a trailing slash, e.g. https://etherscan.io */
  explorerUrl?: string;
  nativeSymbol?: string;
}

export interface WalletOption {
  id: string;
  name: string;
  /** Logo URL. Without one, a generated squircle with the wallet's initial is shown. */
  iconUrl?: string;
  color?: string;
  /** Shows a "Recent" badge. */
  recent?: boolean;
  /** The wallet is detected in this browser. */
  installed?: boolean;
  /** Connects by scanning a QR code with a phone instead of a browser extension. */
  qr?: boolean;
  /** Short helper line under the name. */
  description?: string;
}

/** Lifecycle of anything the user signs: every state gets its own visual. */
export type TxStatus = "idle" | "awaiting-signature" | "pending" | "confirmed" | "failed";

/** Explorer URL for an address or transaction, or undefined without an explorer. */
export function explorerLink(explorerUrl: string | undefined, kind: "address" | "tx", value: string) {
  return explorerUrl ? `${explorerUrl.replace(/\/$/, "")}/${kind}/${value}` : undefined;
}

  3. Add the theme tokens

    This component uses --success, which shadcn does not define by default. Add it to your global CSS:

    app/globals.css
    :root {
  --success: #15803d;
}

.dark {
  --success: #4ade80;
}

@theme inline {
  --color-success: var(--success);
}

  4. Copy the source

    components/ui/price-ticker/price-ticker.tsx
    "use client";

import { useEffect, useRef, useState, type ComponentProps } from "react";
import { motion, useAnimationFrame, useInView, useMotionValue, useReducedMotion } from "motion/react";
import { TrendingDown, TrendingUp } from "lucide-react";
import { cn } from "@/lib/utils";
import { formatPercent, formatUsd, USD_DECIMALS } from "@/lib/web3/format";
import { TokenIcon } from "@/lib/web3/icons";
import { RollingValue } from "@/lib/web3/rolling-value";
import type { Token } from "@/lib/web3/types";

export interface TickerItem {
  /** Pair label, e.g. "ETH/USD". */
  label: string;
  /** Token for the icon. */
  token?: Pick<Token, "symbol" | "iconUrl" | "color">;
  /** Price as a bigint with `priceDecimals` decimals. */
  price: bigint;
  /** Decimals of `price`. @default 8 */
  priceDecimals?: number;
  /** 24h change as a ratio: 0.0214 is +2.14%. */
  change24h?: number;
}

export interface PriceTickerProps
  extends Omit<ComponentProps<"div">, "children" | "onAnimationStart" | "onDrag" | "onDragStart" | "onDragEnd"> {
  /** Pairs to show, in order. */
  items: TickerItem[];
  /** Scroll speed in pixels per second. @default 40 */
  speed?: number;
  /** Scroll direction. @default "left" */
  direction?: "left" | "right";
  /** Pause while hovered or focused. @default true */
  pauseOnHover?: boolean;
  /** Accessible name of the ticker. @default "Live prices" */
  label?: string;
}

function Item({ item }: { item: TickerItem }) {
  const change = item.change24h ?? 0;
  const up = change > 0;
  const down = change < 0;
  return (
    <span className="flex shrink-0 items-center gap-2 px-5 text-sm whitespace-nowrap">
      {item.token ? <TokenIcon token={item.token} size={20} /> : null}
      <span className="font-medium text-foreground">{item.label}</span>
      <span className="font-mono text-foreground">
        <RollingValue value={formatUsd(item.price, item.priceDecimals ?? USD_DECIMALS)} trend={item.price} />
      </span>
      {item.change24h !== undefined ? (
        <span
          className={cn(
            "inline-flex items-center gap-0.5 font-mono text-xs tabular-nums",
            up && "text-[color-mix(in_oklab,var(--success)_75%,var(--foreground))]",
            down && "text-[color-mix(in_oklab,var(--destructive)_80%,var(--foreground))]",
            !up && !down && "text-muted-foreground",
          )}
        >
          {up ? <TrendingUp className="size-3" aria-hidden="true" /> : down ? <TrendingDown className="size-3" aria-hidden="true" /> : null}
          {formatPercent(change, { signed: true })}
        </span>
      ) : null}
    </span>
  );
}

export function PriceTicker({
  items,
  speed = 40,
  direction = "left",
  pauseOnHover = true,
  label = "Live prices",
  className,
  ...props
}: PriceTickerProps) {
  const reduceMotion = useReducedMotion() ?? false;
  const x = useMotionValue(0);
  const track = useRef<HTMLDivElement>(null);
  const [width, setWidth] = useState(0);
  const paused = useRef(false);
  const velocity = useRef(1);

  // One copy's width sets the loop length; re-measured when items or fonts change size.
  useEffect(() => {
    const el = track.current;
    if (!el) return;
    const observer = new ResizeObserver(() => setWidth(el.scrollWidth));
    observer.observe(el);
    return () => observer.disconnect();
  }, []);

  // Offscreen, the loop does no work (it resumes just before the track scrolls back into view).
  const inView = useInView(track, { margin: "200px" });

  useAnimationFrame((_, delta) => {
    if (!inView || reduceMotion || width === 0) return;
    // Ease the speed toward 0 (paused) or 1, so hovering slows rather than snaps.
    const target = paused.current ? 0 : 1;
    velocity.current += (target - velocity.current) * Math.min(1, delta / 180);
    if (Math.abs(target - velocity.current) < 0.005) velocity.current = target;
    if (velocity.current === 0) return;
    const sign = direction === "left" ? -1 : 1;
    let next = x.get() + sign * speed * velocity.current * (delta / 1000);
    if (next <= -width) next += width;
    if (next > 0) next -= width;
    x.set(next);
  });

  const pause = (value: boolean) => {
    if (pauseOnHover) paused.current = value;
  };

  return (
    <div
      role="region"
      aria-label={label}
      onPointerEnter={() => pause(true)}
      onPointerLeave={() => pause(false)}
      onFocus={() => pause(true)}
      onBlur={() => pause(false)}
      className={cn(
        "relative w-full overflow-hidden border-y border-border bg-background py-3",
        "[mask-image:linear-gradient(to_right,transparent,black_8%,black_92%,transparent)] motion-reduce:overflow-x-auto",
        className,
      )}
      {...props}
    >
      <motion.div className="flex w-max" style={{ x }}>
        <div ref={track} className="flex">
          {items.map((item) => (
            <Item key={item.label} item={item} />
          ))}
        </div>
        {/* A second copy makes the loop seamless; it's hidden from assistive tech (and entirely under reduced motion). */}
        <div className="flex motion-reduce:hidden" aria-hidden="true" inert>
          {items.map((item) => (
            <Item key={item.label} item={item} />
          ))}
        </div>
      </motion.div>
    </div>
  );
}

Usage

import { PriceTicker } from "@/components/ui/price-ticker/price-ticker";

<PriceTicker
  items={[{ label: "ETH/USD", token: { symbol: "ETH" }, price: ethPrice, change24h: 0.021 }]}
  speed={40}
/>

API reference

PropTypeDefaultDescription
items*TickerItem[]–Pairs to show, in order.
speednumber40Scroll speed in pixels per second.
direction"left" | "right""left"Scroll direction.
pauseOnHoverbooleantruePause while hovered or focused.
labelstring"Live prices"Accessible name of the ticker.

Also accepts every native <div> attribute, including ref and className.

  • Prices are bigint values with 8 decimals, formatted before display. Each tick rolls the changed digits and flashes green or red.
  • The loop length is measured with a ResizeObserver, so it stays seamless when fonts load or items change.

Accessibility

  • A labelled region; only the first copy of the pairs is exposed to screen readers, and the loop copy is aria-hidden and inert.
  • Hovering or focusing the ticker eases it to a stop so prices can be read.
  • Changes carry an arrow and a sign, not just color, and prices are read as plain text instead of rolling reels.
  • With reduced motion the ticker doesn't move: it becomes a horizontally scrollable row and price updates are color-only.