"use client";
import { useEffect, useEffectEvent, useId, useLayoutEffect, useRef, useState, type CSSProperties, type KeyboardEvent, type PointerEvent } from "react";
import { focusQuietly } from "@/design-system";
import { hostTransport, play } from "@/lib/sound";
/*
* Notifications on a dot-matrix strip, after a recorder's status line: a
* long LCD behind a black bezel, a tone light, and a white chip that counts
* the queue.
*
* Text is set in the page's own typeface (read with getComputedStyle), drawn
* into a small offscreen canvas a dot per pixel, at the matrix's height, and
* thresholded into dots, so any characters work. The dots are drawn round on
* a canvas sized for the screen's pixel ratio: lit ones in the LCD's ink with
* a faint glow, unlit ones as ghosts. Colours come from the CSS variables and
* follow the theme.
*
* The dots keep their pitch in em, so a wider strip shows more columns; a
* strip as narrow as a phone's sets them a little finer, so it still holds
* a short line. A message that fits types on, column by column, and dwells.
* One that's wider than the display scrolls at a constant speed in px/s, holding at its
* start and its end. Hovering or focusing the strip pauses it; arrows step
* through the queue. The canvas only redraws when a column changes, and its
* loop stops while it's idle, paused or off-screen. Under reduced motion
* nothing scrolls: a long message pages through, a screenful at a time.
*
* Screen readers hear each message once, from a polite status region; the
* canvas is hidden from them.
*/
export type Tone = "info" | "warn" | "alert";
export type TickerMessage = { id: number; text: string; tone: Tone };
type Queue = { messages: TickerMessage[]; index: number; waiting: boolean };
/**
* The queue behind a Ticker: `push` adds a message (shown at once if the
* display is idle, queued if it's busy), and the display advances through
* the queue by itself as each message finishes.
*/
export function useTicker({ limit = 9 }: { limit?: number } = {}) {
const [queue, setQueue] = useState<Queue>({ messages: [], index: -1, waiting: false });
const nextId = useRef(0);
function push(text: string, { tone = "info" }: { tone?: Tone } = {}) {
nextId.current += 1;
const message = { id: nextId.current, text, tone };
setQueue((q) => {
const all = [...q.messages, message];
const drop = Math.max(0, all.length - limit);
const messages = all.slice(drop);
// Idle, or the last message has had its turn: show this one now.
if (q.index === -1 || q.waiting) return { messages, index: messages.length - 1, waiting: false };
return { messages, index: Math.max(0, q.index - drop), waiting: false };
});
return message.id;
}
/** The display is done with message `id`: on to the next, or wait for one. */
function finished(id: number) {
setQueue((q) => {
if (q.messages[q.index]?.id !== id) return q;
return q.index < q.messages.length - 1 ? { ...q, index: q.index + 1 } : { ...q, waiting: true };
});
}
function go(index: number) {
setQueue((q) => (q.messages.length ? { ...q, index: Math.min(q.messages.length - 1, Math.max(0, index)), waiting: false } : q));
}
function clear() {
setQueue({ messages: [], index: -1, waiting: false });
}
return {
messages: queue.messages,
index: queue.index,
current: queue.messages[queue.index] ?? null,
/** The last message has finished and nothing is queued. */
waiting: queue.waiting,
push,
finished,
go,
clear,
};
}
export type TickerController = ReturnType<typeof useTicker>;
/* --- The matrix ------------------------------------------------------------ */
const ROWS = 12;
const CAP = 7.5; // rows a capital stands
const BASELINE = 9; // rows from the top to the baseline: room above for accents, three below for descenders
const PITCH = 0.22; // em from one dot to the next
const FINE_PITCH = 0.2; // on a strip narrower than 19.5rem
const THRESHOLD = 0.5; // coverage that lights a dot
const TYPE_RATE = 150; // columns a second while typing on
const DWELL = 2000; // ms a message that fits stays, plus a little per character
const HOLD = 1000; // ms a scrolling message holds at its start and its end
const PAGE = 2400; // ms per screenful under reduced motion
const SPACE = 3; // dark columns a space adds to the one between glyphs
type Bitmap = {
cols: number;
/** Column-major: bits[col * ROWS + row]. */
bits: Uint8Array;
/** Each word's columns, for paging. */
words: [number, number][];
};
/** Graphemes, so an accent or an emoji stays one glyph. */
function graphemes(text: string) {
if (typeof Intl.Segmenter === "function") return [...new Intl.Segmenter(undefined, { granularity: "grapheme" }).segment(text)].map((s) => s.segment);
return Array.from(text);
}
type Glyph = { cols: number; bits: Uint8Array };
/** Glyphs already set, by font and grapheme. Cleared once the page's fonts have loaded. */
const glyphs = new Map<string, Glyph | null>();
let pen: CanvasRenderingContext2D | null = null;
/**
* One grapheme in `font`, a dot per pixel, trimmed to the columns it lights.
* A pixel lights when the glyph covers most of it. Null for blank glyphs.
*/
function glyph(g: string, font: string): Glyph | null {
const key = `${font}\u0000${g}`;
const hit = glyphs.get(key);
if (hit !== undefined) return hit;
pen ??= document.createElement("canvas").getContext("2d", { willReadFrequently: true })!;
const canvas = pen.canvas;
pen.font = font;
const m = pen.measureText(g);
const width = Math.max(4, Math.ceil(m.actualBoundingBoxLeft + m.actualBoundingBoxRight) + 4);
canvas.width = width;
canvas.height = ROWS;
pen.font = font;
pen.fillStyle = "#fff";
pen.textBaseline = "alphabetic";
pen.fillText(g, 2 + m.actualBoundingBoxLeft, BASELINE);
const { data } = pen.getImageData(0, 0, width, ROWS);
let first = width;
let last = -1;
const lit = (c: number, r: number) => data[(r * width + c) * 4 + 3] > THRESHOLD * 255;
for (let c = 0; c < width; c++)
for (let r = 0; r < ROWS; r++)
if (lit(c, r)) {
first = Math.min(first, c);
last = Math.max(last, c);
}
let out: Glyph | null = null;
if (last >= 0) {
const cols = last - first + 1;
const bits = new Uint8Array(cols * ROWS);
for (let c = 0; c < cols; c++) for (let r = 0; r < ROWS; r++) bits[c * ROWS + r] = lit(first + c, r) ? 1 : 0;
out = { cols, bits };
}
glyphs.set(key, out);
return out;
}
/**
* Sets text in the page's typeface, CAP dots to a capital: each glyph
* trimmed to its lit columns and set one dark column after the last, as a
* matrix display spaces its characters.
*/
function rasterize(text: string, family: string, weight: string): Bitmap {
pen ??= document.createElement("canvas").getContext("2d", { willReadFrequently: true })!;
pen.font = `${weight} 100px ${family}`;
const cap = pen.measureText("H").actualBoundingBoxAscent / 100 || 0.7;
const font = `${weight} ${(CAP / cap).toFixed(3)}px ${family}`;
const parts: (Glyph | number)[] = []; // glyphs, and the blank columns between words
const words: [number, number][] = [];
let x = 0;
let word = -1;
for (const g of graphemes(text)) {
const set = /\s/.test(g) ? null : glyph(g, font);
if (!set) {
if (word >= 0) words.push([word, x - 2]);
word = -1;
parts.push(SPACE);
x += SPACE;
continue;
}
if (word < 0) word = x;
parts.push(set);
x += set.cols + 1;
}
if (word >= 0) words.push([word, x - 2]);
const cols = Math.max(1, x - 1);
const bits = new Uint8Array(cols * ROWS);
let at = 0;
for (const part of parts) {
if (typeof part === "number") {
at += part;
continue;
}
bits.set(part.bits, at * ROWS);
at += part.cols + 1;
}
return { cols, bits, words };
}
/** Screenfuls of whole words, for reduced motion; a word too long for one is cut. */
function paginate({ cols, words }: Bitmap, width: number): [number, number][] {
const pages: [number, number][] = [];
let start = -1;
let end = 0;
for (const [a, b] of words) {
if (start >= 0 && b - start + 1 <= width) {
end = b + 1;
continue;
}
if (start >= 0) pages.push([start, end]);
start = a;
while (b - start + 1 > width) {
pages.push([start, start + width]);
start += width;
}
end = b + 1;
}
if (start >= 0) pages.push([start, end]);
return pages.length ? pages : [[0, cols]];
}
const cx = (...parts: (string | false | undefined)[]) => parts.filter(Boolean).join(" ");
const reducedMotion = () => matchMedia("(prefers-reduced-motion: reduce)").matches;
const TONES: Record<Tone, { name: string; light: string; said: string }> = {
// Drawn, a lit light is filled ink (orange is the picked layer's, so warn goes to ink too) and an alert stays red; idle is a hairline ring.
info: { name: "Info", light: "bg-(--device-lcd-ink) shadow-[0_0_0.5em_rgb(255_255_255/0.7)] drawn:bg-(--device-draw-ink)!", said: "" },
warn: { name: "Warn", light: "bg-(--device-hold) shadow-[0_0_0.5em_var(--device-hold)] drawn:bg-(--device-draw-ink)!", said: "Warning: " },
alert: { name: "Alert", light: "animate-pulse bg-(--device-rec) shadow-[0_0_0.5em_var(--device-rec)] motion-reduce:animate-none drawn:bg-(--device-rec)!", said: "Alert: " },
};
type TickerProps = {
controller: TickerController;
label?: string;
/** Scrolling speed, in CSS px per second. */
speed?: number;
className?: string;
};
type Engine = { show: (m: TickerMessage | null) => void; hold: (reason: string, on: boolean) => void };
export function Ticker({ controller, label = "Notifications", speed = 72, className = "" }: TickerProps) {
const ids = useId();
const stripRef = useRef<HTMLDivElement>(null);
const canvasRef = useRef<HTMLCanvasElement>(null);
const engine = useRef<Engine | null>(null);
const speedRef = useRef(speed);
const [hand, setHand] = useState({ hover: false, focus: false });
const { messages, index, current } = controller;
useLayoutEffect(() => {
speedRef.current = speed;
}, [speed]);
// Each message is announced once, when it first reaches the display, whichever order that happens in.
const [heard, setHeard] = useState<{ ids: number[]; message: TickerMessage | null }>({ ids: [], message: null });
if (current && !heard.ids.includes(current.id)) setHeard({ ids: [...heard.ids.slice(-63), current.id], message: current });
const finished = useEffectEvent((id: number) => controller.finished(id));
// The display: one loop draws the strip, and only while a column is changing.
useLayoutEffect(() => {
const strip = stripRef.current!;
const canvas = canvasRef.current!;
const ctx = canvas.getContext("2d")!;
const ghosts = document.createElement("canvas");
let w = 0;
let h = 0;
let dpr = 1;
let pitch = 1;
let cols = 0;
let ink = "#f5f5f5";
let family = "sans-serif";
let weight = "500";
let message: TickerMessage | null = null;
let bmp: Bitmap | null = null;
let phase: "idle" | "type" | "dwell" | "start" | "scroll" | "end" | "rest" | "page" = "idle";
let offset = -1; // the bitmap column under the first screen column; -1 leaves a margin
let limit = Infinity; // bitmap columns from here on stay dark (the next page's)
let reveal = Infinity; // screen columns typed on so far
let pages: [number, number][] = [];
let page = 0;
let acc = 0;
const holds = new Set<string>();
let raf = 0;
let last = 0;
let timer = 0;
let timerFn: (() => void) | null = null;
let timerLeft = 0;
let timerAt = 0;
/* Timers that stop while the display is held. */
const arm = () => {
timerAt = performance.now();
timer = window.setTimeout(() => {
const fn = timerFn;
timerFn = null;
fn?.();
}, timerLeft);
};
const wait = (ms: number, fn: () => void) => {
clearTimeout(timer);
timerFn = fn;
timerLeft = ms;
if (!holds.size) arm();
};
const fits = () => !!bmp && bmp.cols + 2 <= cols;
function measure() {
const box = strip.getBoundingClientRect();
dpr = Math.min(3, window.devicePixelRatio || 1);
w = box.width;
h = box.height;
pitch = h / ROWS;
cols = Math.max(1, Math.floor(w / pitch));
canvas.width = ghosts.width = Math.round(w * dpr);
canvas.height = ghosts.height = Math.round(h * dpr);
if (bmp && phase === "page") pages = paginate(bmp, cols - 2);
if (bmp && (phase === "scroll" || phase === "end")) offset = Math.min(offset, Math.max(-1, bmp.cols + 1 - cols));
}
function colours() {
const style = getComputedStyle(strip);
ink = style.getPropertyValue("--device-lcd-ink").trim() || "#f5f5f5";
family = style.fontFamily;
weight = style.fontWeight;
}
const x0 = () => (w - cols * pitch) / 2 + pitch / 2;
function paintGhosts() {
const g = ghosts.getContext("2d")!;
g.setTransform(dpr, 0, 0, dpr, 0, 0);
g.clearRect(0, 0, w, h);
g.globalAlpha = 0.08;
g.fillStyle = ink;
g.beginPath();
const r = pitch * 0.36;
for (let c = 0; c < cols; c++)
for (let row = 0; row < ROWS; row++) {
const x = x0() + c * pitch;
const y = pitch / 2 + row * pitch;
g.moveTo(x + r, y);
g.arc(x, y, r, 0, Math.PI * 2);
}
g.fill();
}
function draw() {
ctx.setTransform(1, 0, 0, 1, 0, 0);
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.drawImage(ghosts, 0, 0);
if (!bmp) return;
ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
const r = pitch * 0.36;
const lit = new Path2D();
const end = Math.min(bmp.cols, limit);
for (let c = 0; c < cols && c < reveal; c++) {
const col = offset + c;
if (col < 0 || col >= end) continue;
const x = x0() + c * pitch;
for (let row = 0; row < ROWS; row++) {
if (!bmp.bits[col * ROWS + row]) continue;
const y = pitch / 2 + row * pitch;
lit.moveTo(x + r, y);
lit.arc(x, y, r, 0, Math.PI * 2);
}
}
ctx.fillStyle = ink;
// The glow, then the dots themselves on top of it.
ctx.globalAlpha = 0.55;
ctx.shadowColor = ink;
ctx.shadowBlur = pitch * dpr * 1.6;
ctx.fill(lit);
ctx.shadowBlur = 0;
ctx.globalAlpha = 1;
ctx.fill(lit);
// The write head: the column being typed on, faintly lit.
if (phase === "type" && reveal < cols) {
const x = x0() + Math.floor(reveal) * pitch;
ctx.globalAlpha = 0.3;
ctx.beginPath();
for (let row = 0; row < ROWS; row++) {
const y = pitch / 2 + row * pitch;
ctx.moveTo(x + r, y);
ctx.arc(x, y, r, 0, Math.PI * 2);
}
ctx.fill();
ctx.globalAlpha = 1;
}
}
function frame(now: number) {
const dt = Math.min(0.1, (now - last) / 1000);
last = now;
raf = 0;
if (!bmp) return;
if (phase === "type") {
const before = Math.floor(reveal);
const span = Math.min(cols, bmp.cols + 2);
reveal = Math.min(span, reveal + TYPE_RATE * dt);
if (Math.floor(reveal) !== before) draw();
if (reveal >= span) {
reveal = Infinity;
draw();
typed();
return;
}
} else if (phase === "scroll") {
const end = bmp.cols + 1 - cols;
acc += (speedRef.current * dt) / pitch;
let moved = false;
while (acc >= 1 && offset < end) {
offset++;
acc -= 1;
moved = true;
}
if (moved) draw();
if (offset >= end) {
phase = "end";
wait(HOLD, done);
return;
}
} else return;
run();
}
function run() {
if (raf || holds.size) return;
last = performance.now();
raf = requestAnimationFrame(frame);
}
function typed() {
if (fits()) {
phase = "dwell";
wait(DWELL + (message?.text.length ?? 0) * 40, done);
} else {
phase = "start";
wait(HOLD, () => {
phase = "scroll";
acc = 0;
run();
});
}
}
function done() {
const id = message?.id;
const scrolled = !fits();
phase = "rest";
if (id !== undefined) finished(id);
// Nothing after it: a long message comes back to its start and rests there.
if (scrolled) {
wait(HOLD, () => {
offset = -1;
draw();
});
}
}
function showPage() {
const [a, b] = pages[page];
offset = a - 1;
limit = b;
draw();
wait(PAGE, () => {
if (page < pages.length - 1) {
page++;
showPage();
} else {
phase = "rest";
if (message) finished(message.id);
// Back to the first screenful.
if (pages.length > 1)
wait(PAGE, () => {
page = 0;
showPage();
});
}
});
}
function show(m: TickerMessage | null) {
clearTimeout(timer);
timerFn = null;
cancelAnimationFrame(raf);
raf = 0;
message = m;
bmp = m ? rasterize(m.text, family, weight) : null;
offset = -1;
limit = Infinity;
reveal = Infinity;
acc = 0;
if (!bmp) {
phase = "idle";
draw();
} else if (reducedMotion()) {
phase = "page";
pages = paginate(bmp, cols - 2);
page = 0;
showPage();
} else {
phase = "type";
reveal = 0;
draw();
run();
}
}
function hold(reason: string, on: boolean) {
const was = holds.size > 0;
if (on) holds.add(reason);
else holds.delete(reason);
const now = holds.size > 0;
if (now === was) return;
if (now) {
cancelAnimationFrame(raf);
raf = 0;
if (timerFn) {
clearTimeout(timer);
timerLeft = Math.max(0, timerLeft - (performance.now() - timerAt));
}
} else {
if (timerFn) arm();
run();
}
}
engine.current = { show, hold };
colours();
measure();
paintGhosts();
draw();
// Size: the pitch follows the strip's height (set in em), so a wider strip shows more columns.
const resize = new ResizeObserver(() => {
measure();
paintGhosts();
draw();
});
resize.observe(strip);
// Off-screen, nothing moves.
const seen = new IntersectionObserver(([entry]) => hold("offscreen", !entry.isIntersecting));
seen.observe(strip);
// Theme: read the colours again and redraw.
const retheme = () => {
colours();
paintGhosts();
draw();
};
const theme = new MutationObserver(retheme);
theme.observe(document.documentElement, { attributes: true, attributeFilter: ["class", "data-theme", "style"] });
const scheme = matchMedia("(prefers-color-scheme: dark)");
scheme.addEventListener("change", retheme);
// Once the typeface has loaded, set the message again in it.
let live = true;
document.fonts?.ready.then(() => {
if (!live) return;
glyphs.clear();
if (!message) return;
colours();
const fresh = rasterize(message.text, family, weight);
if (bmp && fresh.cols === bmp.cols && fresh.bits.every((b, i) => b === bmp!.bits[i])) return;
bmp = fresh;
draw();
});
return () => {
live = false;
cancelAnimationFrame(raf);
clearTimeout(timer);
resize.disconnect();
seen.disconnect();
theme.disconnect();
scheme.removeEventListener("change", retheme);
engine.current = null;
};
}, []);
// A different message on the display.
const shown = current?.id;
const showCurrent = useEffectEvent(() => engine.current?.show(current));
useEffect(() => {
showCurrent();
}, [shown]);
// A hand on the strip holds it.
useEffect(() => {
engine.current?.hold("hand", hand.hover || hand.focus);
}, [hand]);
function onKeyDown(e: KeyboardEvent<HTMLDivElement>) {
const to = { ArrowLeft: index - 1, ArrowRight: index + 1, Home: 0, End: messages.length - 1 }[e.key];
if (to === undefined) return;
e.preventDefault();
if (!messages.length || to < 0 || to >= messages.length || to === index) return play("bump", { gain: 0.6 });
play("tick", { gain: 0.6 });
controller.go(to);
}
const tone = current ? TONES[current.tone] : null;
const held = hand.hover || hand.focus;
return (
<div data-part="bezel" className={cx("@container/ticker rounded-[0.9em] bg-(--device-rim) p-[0.3em] shadow-[0_1px_0_rgb(255_255_255/0.7),inset_0_1px_2px_rgb(0_0_0/0.6)] dark:shadow-[0_1px_0_rgb(255_255_255/0.06),inset_0_1px_2px_rgb(0_0_0/0.6)]", className)}>
<div data-part="lcd" className="relative overflow-hidden rounded-[0.65em] px-[0.6em] pb-[0.6em] pt-[0.55em] text-(--device-lcd-ink) [background:var(--device-lcd)] shadow-(--device-lcd-edge)">
<div aria-hidden className="flex items-center gap-[0.45em]">
<span data-part="light" className={cx("size-[0.5em] shrink-0 rounded-full transition-[background-color,box-shadow] duration-(--duration-exit)", tone ? tone.light : "bg-white/15")} />
<span key={current?.id} className="animate-enter text-[0.58em] font-semibold uppercase leading-none tracking-[0.14em] text-(--device-lcd-dim) drawn:opacity-60">
{tone ? tone.name : "Idle"}
</span>
{held && current && (
<svg viewBox="0 0 8 8" className="size-[0.5em] fill-(--device-lcd-dim) drawn:fill-(--device-draw-ink)! drawn:opacity-60">
<path d="M1.2 1h1.9v6H1.2zM4.9 1h1.9v6H4.9z" />
</svg>
)}
<span data-part="chip" className="ml-auto inline-flex items-center rounded-[0.4em] bg-white px-[0.42em] py-[0.24em] text-black">
<span className="text-[0.58em] font-semibold uppercase leading-none tabular-nums tracking-[0.02em]">
Msg {messages.length ? `${index + 1}/${messages.length}` : "—"}
</span>
</span>
</div>
{/* The matrix. */}
<div
ref={stripRef}
role="group"
tabIndex={0}
aria-label={label}
aria-describedby={`${ids}-now ${ids}-hint`}
onKeyDown={onKeyDown}
onPointerEnter={(e: PointerEvent) => e.pointerType === "mouse" && setHand((h) => ({ ...h, hover: true }))}
onPointerLeave={() => setHand((h) => ({ ...h, hover: false }))}
onFocus={() => setHand((h) => ({ ...h, focus: true }))}
onBlur={() => setHand((h) => ({ ...h, focus: false }))}
onPointerDown={(e) => e.button === 0 && focusQuietly(e.currentTarget)}
data-part="matrix"
className="relative mt-[0.45em] h-(--fine) rounded-[0.2em] font-semibold outline-offset-4 @[19.5rem]/ticker:h-(--pitch)"
style={{ "--pitch": `${ROWS * PITCH}em`, "--fine": `${ROWS * FINE_PITCH}em` } as CSSProperties}
>
{/* Drawn, the dots are the matrix's content: the LCD's light ink inverted to dark on the light canvas, as it is on the dark one. */}
<canvas ref={canvasRef} aria-hidden className="absolute inset-0 size-full drawn:[--draw-invert:1] drawn:dark:[--draw-invert:0] drawn:[filter:grayscale(1)_invert(var(--draw-invert))]! drawn:opacity-80!" />
</div>
{/* Glass. */}
<div aria-hidden data-part="glass" className="pointer-events-none absolute inset-0 [background:var(--screen-glass)]" />
</div>
<p id={`${ids}-now`} className="sr-only">
{current ? `Message ${index + 1} of ${messages.length}: ${current.text}` : "No messages"}
</p>
<p id={`${ids}-hint`} className="sr-only">
Hover or focus to pause. Left and right arrows step through the messages.
</p>
<div role="status" aria-live="polite" className="sr-only">
{heard.message && (
<p key={heard.message.id}>
{TONES[heard.message.tone].said}
{heard.message.text}
</p>
)}
</div>
</div>
);
}
/* --- Demo: a recorder's status line ---------------------------------------- */
/** Every message types on, even on a phone's strip, but the card alert: it's meant to scroll. */
const ARRIVALS: { text: string; tone: Tone }[] = [
{ text: "SAVED take_04", tone: "info" },
{ text: "SYNCED 3 TAKES", tone: "info" },
{ text: "BATTERY 12%", tone: "warn" },
{ text: "CARD FULL — FREE 2.1 GB TO KEEP RECORDING", tone: "alert" },
];
/** What Notify sends, in turn. */
const SAMPLES: { text: string; tone: Tone }[] = [
{ text: "TAKE 05 ARMED", tone: "info" },
{ text: "Zoë left 2 notes", tone: "info" },
{ text: "MIC 2 CLIPPING", tone: "alert" },
{ text: "BACKUP DONE", tone: "info" },
{ text: "48V ON INPUT 2", tone: "warn" },
...ARRIVALS,
];
const GAP = 2600; // ms between arrivals while untouched
type KeyId = "prev" | "next" | "notify" | "clear";
const KEYS: { id: KeyId; name: string; label?: string; glyph?: string }[] = [
{ id: "prev", name: "Previous message", glyph: "M9.5 3.5 5 8l4.5 4.5" },
{ id: "next", name: "Next message", glyph: "M6.5 3.5 11 8l-4.5 4.5" },
{ id: "notify", name: "Notify", label: "Notify" },
{ id: "clear", name: "Clear", label: "Clear" },
];
export default function Demo() {
const ticker = useTicker();
const rootRef = useRef<HTMLDivElement>(null);
const auto = useRef(true); // messages arrive by themselves until a hand arrives
const sample = useRef(0);
function arrive(m: { text: string; tone: Tone }, byItself: boolean) {
ticker.push(m.text, { tone: m.tone });
if (!byItself || hostTransport(rootRef.current) === "play") play("open", { gain: 0.45, pitch: m.tone === "alert" ? 1.12 : m.tone === "warn" ? 1.05 : 1 });
}
// Untouched, the recorder reports in: four messages, a moment apart; once they've all shown, it starts over.
const arriveNext = useEffectEvent((i: number) => arrive(ARRIVALS[i], true));
const allShown = useEffectEvent(() => ticker.waiting);
const restart = useEffectEvent(() => ticker.clear());
useEffect(() => {
const root = rootRef.current;
if (hostTransport(root) === "stop") return;
if (reducedMotion()) {
const id = setTimeout(() => ARRIVALS.forEach((_, i) => arriveNext(i)), 300);
return () => clearTimeout(id);
}
let i = 0;
let id = 0;
const step = () => {
if (!auto.current) return;
if (i < ARRIVALS.length) {
arriveNext(i++);
id = window.setTimeout(step, GAP);
} else if (!allShown()) id = window.setTimeout(step, 400);
else
id = window.setTimeout(() => {
if (!auto.current) return;
restart();
i = 0;
id = window.setTimeout(step, 900);
}, 2600);
};
id = window.setTimeout(step, 300);
return () => clearTimeout(id);
}, []);
function notify() {
const m = SAMPLES[sample.current % SAMPLES.length];
sample.current += 1;
arrive(m, false);
}
function clear() {
if (!ticker.messages.length) return play("bump", { gain: 0.6 });
ticker.clear();
play("close", { gain: 0.5 });
}
function step(delta: number) {
const to = ticker.index + delta;
if (to < 0 || to >= ticker.messages.length) return play("bump", { gain: 0.6 });
ticker.go(to);
}
function onKey(id: KeyId) {
if (id === "prev") step(-1);
else if (id === "next") step(1);
else if (id === "notify") notify();
else clear();
}
return (
<div
ref={rootRef}
onPointerDownCapture={() => (auto.current = false)}
onKeyDownCapture={() => (auto.current = false)}
className="@container w-full max-w-[440px] select-none"
>
<div data-part="plate" className="relative isolate animate-enter overflow-hidden rounded-[1.25em] p-[0.9em] text-[clamp(11px,4.4cqw,14px)] [background:var(--device-body)] shadow-[var(--device-body-edge),0_1px_2px_rgb(0_0_0/0.06),0_16px_32px_-18px_rgb(0_0_0/0.3)]">
<div aria-hidden className="device-grain pointer-events-none absolute inset-0 -z-10 rounded-[inherit]" />
<Ticker controller={ticker} />
{/* The keys: two pairs on a narrow plate, so it stands taller in a phone's box; one row from 20rem. */}
<div className="mt-[0.8em] grid grid-cols-2 gap-[0.45em] @[20rem]:flex @[20rem]:items-center">
{KEYS.map((k) => (
<button
key={k.id}
type="button"
data-sound="key"
aria-label={k.label ? undefined : k.name}
onPointerDown={(e) => e.button === 0 && focusQuietly(e.currentTarget)}
onClick={() => onKey(k.id)}
data-part="key"
className={cx("group/key rounded-[0.7em] outline-offset-2", k.label ? "@[20rem]:flex-1" : "@[20rem]:w-[2.6em] @[20rem]:shrink-0")}
>
<span className="grid h-[2.75em] place-items-center rounded-[0.7em] text-(--device-key-ink) @[20rem]:h-[2.5em] [background:var(--device-key-face)] shadow-(--device-key-shadow) transition-[transform,box-shadow] duration-(--duration-exit) ease-out group-active/key:translate-y-[2px] group-active/key:shadow-(--device-key-shadow-pressed) group-active/key:duration-75">
{k.glyph ? (
<svg aria-hidden data-part="lettering" viewBox="0 0 16 16" className="size-[1.1em] fill-none stroke-current [filter:var(--device-engrave-glyph)] drawn:[filter:none]!" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round">
<path d={k.glyph} />
</svg>
) : (
<span data-part="lettering" className="text-[0.8em] font-medium uppercase leading-none tracking-[0.03em] [text-shadow:var(--device-engrave)]">{k.label}</span>
)}
</span>
</button>
))}
</div>
</div>
</div>
);
}
