"use client";
import { useEffect, useState, type ComponentType, type CSSProperties, type ReactNode } from "react";
/*
* Abstract shapes for the ways an agent works. Each is a small metaphor: a
* spark while it thinks, a graph while it searches, a cube arranging itself
* while it organizes, orbits while it weighs options, a form finding its shape
* while it plans, a cube building itself while it builds, tiles folding in
* turn while tools run, one continuous thread while it writes.
*
* AgentShape takes the current phase and crossfades between them. Every shape
* is SVG, plain elements or CSS 3D driven by the design system's keyframes
* (stretch, trace, morph, assemble, twist, build, wave), drawn in currentColor
* with a single accent.
* Under prefers-reduced-motion each holds a deliberate still frame, and each
* carries a label for screen readers.
*/
type ShapeProps = { label?: string; size?: number; className?: string };
function Frame({ label, size, className, children }: { label: string; size: number; className: string; children: ReactNode }) {
return (
<span role="status" aria-label={label} className={`relative inline-block shrink-0 ${className}`} style={{ width: size, height: size }}>
{children}
</span>
);
}
/** A negative delay that puts a looping animation `fraction` of the way through, so nothing starts at rest. */
const offset = (fraction: number, duration: number) => `${-(((fraction % 1) + 1) % 1) * duration}ms`;
/* --- Spark: thinking ---------------------------------------------------- */
const RAYS = 8;
const STRETCH = 1600;
/** Rays reaching out from a point, a wave running round the ring. */
export function Spark({ label = "Thinking", size = 32, className = "" }: ShapeProps) {
return (
<Frame label={label} size={size} className={className}>
<span aria-hidden className="absolute inset-0 animate-spin [animation-duration:9s] motion-reduce:animate-none">
{Array.from({ length: RAYS }, (_, i) => (
<span key={i} className="absolute inset-0" style={{ transform: `rotate(${(i * 360) / RAYS}deg)` }}>
<span
className={`absolute bottom-[64%] left-1/2 h-[34%] w-[9%] -translate-x-1/2 origin-bottom animate-stretch rounded-full bg-current motion-reduce:animate-none ${i % 2 ? "motion-reduce:scale-y-50" : ""}`}
style={{ animationDelay: offset(1 - i / RAYS, STRETCH) }}
/>
</span>
))}
</span>
<span aria-hidden className="absolute top-1/2 left-1/2 size-[18%] -translate-1/2 rounded-full bg-accent-strong" />
</Frame>
);
}
/* --- Orbit: reasoning --------------------------------------------------- */
const ELLIPSE = "M3 16a13 5 0 1 0 26 0a13 5 0 1 0 -26 0";
const ORBITS = [
{ angle: 0, duration: 1800 },
{ angle: 60, duration: 2400 },
{ angle: 120, duration: 3000 },
];
/** Three ideas in motion at once: comets on tilted orbits around a breathing core. */
export function Orbit({ label = "Reasoning", size = 32, className = "" }: ShapeProps) {
return (
<Frame label={label} size={size} className={className}>
<svg aria-hidden viewBox="0 0 32 32" fill="none" className="size-full overflow-visible">
{ORBITS.map(({ angle, duration }, i) => (
<g key={angle} transform={`rotate(${angle} 16 16)`}>
<path d={ELLIPSE} className="stroke-line-strong" strokeWidth={1} />
<path
d={ELLIPSE}
pathLength={1}
strokeDasharray="0.12 0.88"
strokeWidth={1.75}
strokeLinecap="round"
className={`animate-trace motion-reduce:animate-none ${i === 0 ? "stroke-accent-strong" : "stroke-current"}`}
style={{ animationDuration: `${duration}ms`, animationDelay: offset(i / 3, duration) }}
/>
</g>
))}
<circle
cx={16}
cy={16}
r={3}
fill="currentColor"
className="origin-center animate-wave [transform-box:fill-box] motion-reduce:animate-none"
/>
</svg>
</Frame>
);
}
/* --- Graph: searching --------------------------------------------------- */
const NODES: [number, number][] = [
[6, 7],
[18, 4],
[28, 12],
[23, 26],
[9, 27],
[4, 17],
];
const CHORDS: [number, number][] = [
[1, 4],
[2, 5],
];
const TRACE = 2400;
const SIGNAL = 0.16;
// The signal runs a closed loop through every node. Each node's distance
// along that loop decides when it lights up.
const LOOP = `M${NODES.map(([x, y]) => `${x} ${y}`).join("L")}Z`;
const NODE_AT = (() => {
const edges = NODES.map(([x, y], i) => {
const [nx, ny] = NODES[(i + 1) % NODES.length];
return Math.hypot(nx - x, ny - y);
});
const total = edges.reduce((sum, d) => sum + d, 0);
return NODES.map((_, i) => edges.slice(0, i).reduce((sum, d) => sum + d, 0) / total);
})();
/** A signal hopping between sources; each lights up as it arrives. */
export function Graph({ label = "Searching", size = 32, className = "" }: ShapeProps) {
return (
<Frame label={label} size={size} className={className}>
<svg aria-hidden viewBox="0 0 32 32" fill="none" className="size-full overflow-visible">
<path d={LOOP} className="stroke-line-strong" strokeWidth={1} strokeLinejoin="round" />
{CHORDS.map(([a, b]) => (
<line
key={`${a}-${b}`}
x1={NODES[a][0]}
y1={NODES[a][1]}
x2={NODES[b][0]}
y2={NODES[b][1]}
className="stroke-line-strong"
strokeWidth={1}
/>
))}
<path
d={LOOP}
pathLength={1}
strokeDasharray={`${SIGNAL} ${1 - SIGNAL}`}
strokeWidth={1.75}
strokeLinecap="round"
strokeLinejoin="round"
className="animate-trace stroke-accent-strong motion-reduce:animate-none"
style={{ animationDuration: `${TRACE}ms` }}
/>
{NODES.map(([x, y], i) => (
<circle
key={i}
cx={x}
cy={y}
r={2.4}
fill="currentColor"
className="origin-center animate-wave [transform-box:fill-box] motion-reduce:animate-none"
// Peak (the keyframe's 50%) when the head of the signal reaches the node.
style={{ animationDuration: `${TRACE}ms`, animationDelay: offset(0.5 - NODE_AT[i] + SIGNAL, TRACE) }}
/>
))}
</svg>
</Frame>
);
}
/* --- Morph: planning ---------------------------------------------------- */
const MORPH = 3200;
/** An idea finding its shape: circle, squircle, diamond, leaf, and round again. */
export function Morph({ label = "Planning", size = 32, className = "" }: ShapeProps) {
return (
<Frame label={label} size={size} className={className}>
{/* A ghost outline trails the form by a beat. */}
<span
aria-hidden
className="absolute inset-[14%] animate-morph rounded-full border-[1.5px] border-accent-strong opacity-70 motion-reduce:animate-none"
style={{ animationDelay: offset(-0.1, MORPH) }}
/>
<span aria-hidden className="absolute inset-[24%] animate-morph rounded-full bg-current motion-reduce:animate-none" />
</Frame>
);
}
/* --- Thread: writing ---------------------------------------------------- */
// A 3:2 Lissajous figure, sampled once.
const CURVE = (() => {
const steps = 120;
const points = Array.from({ length: steps }, (_, i) => {
const t = (i / steps) * Math.PI * 2;
return `${(16 + 12.5 * Math.cos(3 * t)).toFixed(2)} ${(16 + 10 * Math.sin(2 * t)).toFixed(2)}`;
});
return `M${points.join("L")}Z`;
})();
const THREAD = 3200;
// Tail first, head last: longer, fainter dashes whose heads line up.
const STRANDS = [
{ length: 0.26, opacity: 0.2 },
{ length: 0.14, opacity: 0.5 },
{ length: 0.05, opacity: 1 },
];
/** A train of thought: one continuous line with a bright head and a fading tail. */
export function Thread({ label = "Writing", size = 32, className = "" }: ShapeProps) {
const longest = STRANDS[0].length;
return (
<Frame label={label} size={size} className={className}>
<svg aria-hidden viewBox="0 0 32 32" fill="none" className="size-full overflow-visible">
<path d={CURVE} className="stroke-line-strong" strokeWidth={1} />
{STRANDS.map(({ length, opacity }, i) => (
<path
key={length}
d={CURVE}
pathLength={1}
strokeDasharray={`${length} ${1 - length}`}
strokeWidth={1.75}
strokeLinecap="round"
opacity={opacity}
className={`animate-trace motion-reduce:animate-none ${i === STRANDS.length - 1 ? "stroke-accent-strong" : "stroke-current"}`}
// Shorter strands run slightly ahead so every head sits at the same point.
style={{ animationDuration: `${THREAD}ms`, animationDelay: offset(longest - length, THREAD) }}
/>
))}
</svg>
</Frame>
);
}
/* --- Fold: running ------------------------------------------------------ */
const ASSEMBLE = 2000;
// Grid order is top-left, top-right, bottom-left, bottom-right; each folds out
// along its own diagonal, in clockwise turn.
const TILES = [
{ fx: "-45%", fy: "-45%", turn: 0 },
{ fx: "45%", fy: "-45%", turn: 1 },
{ fx: "-45%", fy: "45%", turn: 3 },
{ fx: "45%", fy: "45%", turn: 2 },
];
/** Steps running in turn: four tiles fold out and settle back, one after another. */
export function Fold({ label = "Running", size = 32, className = "" }: ShapeProps) {
return (
<Frame label={label} size={size} className={className}>
<span aria-hidden className="absolute inset-[20%] grid grid-cols-2 grid-rows-2 gap-[12%]">
{TILES.map(({ fx, fy, turn }, i) => (
<span
key={i}
className={`animate-assemble rounded-[2px] motion-reduce:animate-none ${i === 3 ? "bg-accent-strong" : "bg-current"}`}
style={{ "--fx": fx, "--fy": fy, animationDelay: offset(-turn / 4, ASSEMBLE) } as CSSProperties}
/>
))}
</span>
</Frame>
);
}
/* --- Cubes: shared parts ------------------------------------------------- */
// Real CSS 3D, viewed isometrically with no perspective, so the browser sorts
// the faces as blocks move. Faces are shaded by how much ink they carry,
// mixed against the surface so they stay opaque (opacity would flatten 3D).
const ISOMETRIC = "rotateX(-35.26deg) rotateY(45deg)";
const FACES = [
{ turn: "rotateX(90deg)", ink: 100 }, // top
{ turn: "rotateY(0deg)", ink: 62 },
{ turn: "rotateY(180deg)", ink: 62 },
{ turn: "rotateY(90deg)", ink: 38 },
{ turn: "rotateY(-90deg)", ink: 38 },
]; // the bottom never faces the viewer
/** Edge of one block, and the distance from the cube's centre to a block's centre. */
const cubeMetrics = (size: number) => {
const edge = size * 0.26;
return { edge, half: (edge + size * 0.03) / 2 };
};
/** The eight block centres of a 2×2×2 cube, bottom layer first, back to front. */
const BLOCKS = (half: number): [number, number, number][] =>
[1, -1].flatMap((y) =>
[
[-1, -1],
[1, -1],
[-1, 1],
[1, 1],
].map(([x, z]): [number, number, number] => [x * half, y * half, z * half]),
);
function Cubelet({
at,
edge,
accent = false,
className = "",
style,
faceStyle,
}: {
at: [number, number, number];
edge: number;
accent?: boolean;
className?: string;
style?: CSSProperties;
/** Applied to every face; opacity belongs here, since on a 3D parent it would flatten it. */
faceStyle?: CSSProperties;
}) {
const color = accent ? "var(--accent-strong)" : "currentColor";
return (
<span className="absolute top-0 left-0 [transform-style:preserve-3d]" style={{ transform: `translate3d(${at[0]}px, ${at[1]}px, ${at[2]}px)` }}>
<span className={`absolute top-0 left-0 [transform-style:preserve-3d] ${className}`} style={style}>
{FACES.map(({ turn, ink }) => (
<span
key={turn}
className="absolute"
style={{
width: edge,
height: edge,
left: -edge / 2,
top: -edge / 2,
transform: `${turn} translateZ(${edge / 2}px)`,
background: `color-mix(in oklab, ${color} ${ink}%, var(--surface))`,
...faceStyle,
}}
/>
))}
</span>
</span>
);
}
/** Centres a zero-size 3D origin in the frame and turns it isometric. */
function Scene({ children, className = "" }: { children: ReactNode; className?: string }) {
return (
<span aria-hidden className="absolute inset-0 grid place-items-center">
<span className={`relative [transform-style:preserve-3d] ${className}`} style={{ transform: ISOMETRIC }}>
{children}
</span>
</span>
);
}
/* --- Cube: organizing --------------------------------------------------- */
/** Arranging itself: the top and bottom layers take turns twisting a quarter, like a puzzle cube. */
export function Cube({ label = "Organizing", size = 32, className = "" }: ShapeProps) {
const { edge, half } = cubeMetrics(size);
const blocks = BLOCKS(half);
return (
<Frame label={label} size={size} className={className}>
<Scene>
{/* Bottom layer first. Playing the same turn in reverse puts its moves in the top layer's pauses. */}
{[blocks.slice(0, 4), blocks.slice(4)].map((layer, i) => (
<span
key={i}
className={`absolute top-0 left-0 animate-twist [transform-style:preserve-3d] motion-reduce:animate-none ${i === 0 ? "[animation-direction:reverse]" : ""}`}
>
{layer.map((at, j) => (
<Cubelet key={j} at={at} edge={edge} accent={i === 1 && j === 3} />
))}
</span>
))}
</Scene>
</Frame>
);
}
/* --- Stack: building ---------------------------------------------------- */
const DROP_WINDOW = 2 / 9;
/**
* Building itself: blocks drop into place bottom-up, the cube holds, then they
* lift away top-down. One shared --build value drives every block, so the
* order reverses on the way out without separate keyframes.
*/
export function Stack({ label = "Building", size = 32, className = "" }: ShapeProps) {
const { edge, half } = cubeMetrics(size);
const lift = edge * 2.2;
return (
<Frame label={label} size={size} className={className}>
<Scene className="animate-build motion-reduce:animate-none">
{BLOCKS(half).map((at, i) => {
// Block i falls while --build runs from i/9 to (i+2)/9: 1 while waiting above, 0 once placed.
const away = `clamp(0, (${(i + 2) / 9} - var(--build)) / ${DROP_WINDOW}, 1)`;
return (
<Cubelet
key={i}
at={at}
edge={edge}
accent={i === 7}
style={{ transform: `translateY(calc(${away} * ${-lift}px))` }}
faceStyle={{ opacity: `calc(1 - ${away})` }}
/>
);
})}
</Scene>
</Frame>
);
}
/* --- AgentShape: one glyph that follows the agent's phase --------------- */
export type AgentPhase =
| "thinking"
| "searching"
| "organizing"
| "reasoning"
| "planning"
| "building"
| "running"
| "writing";
export const phases: Record<AgentPhase, { name: string; label: string; Shape: ComponentType<ShapeProps> }> = {
thinking: { name: "Spark", label: "Thinking", Shape: Spark },
searching: { name: "Graph", label: "Searching", Shape: Graph },
organizing: { name: "Cube", label: "Organizing", Shape: Cube },
reasoning: { name: "Orbit", label: "Reasoning", Shape: Orbit },
planning: { name: "Morph", label: "Planning", Shape: Morph },
building: { name: "Stack", label: "Building", Shape: Stack },
running: { name: "Fold", label: "Running", Shape: Fold },
writing: { name: "Thread", label: "Writing", Shape: Thread },
};
/**
* Pass the agent's current phase; the glyph crossfades to the matching shape.
* Screen readers hear the label (or the phase name) when it changes.
*/
export function AgentShape({ phase, label, size = 32, className = "" }: ShapeProps & { phase: AgentPhase }) {
const [shown, setShown] = useState(phase);
const [leaving, setLeaving] = useState<AgentPhase | null>(null);
// Swap during render rather than in an effect, so the new shape never lags a frame.
if (phase !== shown) {
setLeaving(shown);
setShown(phase);
}
useEffect(() => {
if (!leaving) return;
const id = setTimeout(() => setLeaving(null), 150);
return () => clearTimeout(id);
}, [leaving]);
const { Shape } = phases[shown];
const Leaving = leaving ? phases[leaving].Shape : null;
return (
<span role="status" className={`inline-grid shrink-0 ${className}`} style={{ width: size, height: size }}>
<span className="sr-only">{label ?? phases[shown].label}</span>
{Leaving && (
<span
key={`out-${leaving}`}
aria-hidden
className="col-start-1 row-start-1 flex"
// The entrance keyframe played backwards, at exit speed.
style={{ animation: "enter var(--duration-exit) var(--ease-out) reverse both" }}
>
<Leaving size={size} />
</span>
)}
<span key={shown} aria-hidden className="col-start-1 row-start-1 flex animate-enter">
<Shape size={size} />
</span>
</span>
);
}
/* --- Demo --------------------------------------------------------------- */
const SCRIPT: { phase: AgentPhase; line: string }[] = [
{ phase: "thinking", line: "Thinking it through" },
{ phase: "searching", line: "Searching 12 sources" },
{ phase: "organizing", line: "Organizing the results" },
{ phase: "reasoning", line: "Weighing 3 approaches" },
{ phase: "planning", line: "Planning the changes" },
{ phase: "building", line: "Building the project" },
{ phase: "running", line: "Running the tests" },
{ phase: "writing", line: "Drafting the answer" },
];
function Shimmer({ children }: { children: ReactNode }) {
return (
<span
className="animate-shimmer bg-clip-text text-transparent motion-reduce:animate-none motion-reduce:text-muted"
style={{
backgroundImage:
"linear-gradient(90deg, var(--muted) 0%, var(--muted) 40%, var(--ink) 50%, var(--muted) 60%, var(--muted) 100%)",
backgroundSize: "200% 100%",
}}
>
{children}
</span>
);
}
// The demo sizes itself to its container ("demo"), not the viewport: narrow
// stages (gallery cards, phones) get a compact grid, wide ones get captioned
// tiles. Each tile is a container too ("tile"), so name both in queries.
function Tile({ name, phase, children, index }: { name: string; phase: string; children: ReactNode; index: number }) {
return (
<figure
className="@container/tile flex animate-enter flex-col overflow-hidden rounded-xl bg-surface shadow-md"
style={{ animationDelay: `calc(${index} * var(--stagger))` }}
>
<div className="flex items-center justify-center pt-2.5 text-ink @md/demo:h-15 @md/demo:pt-0">
{/* zoom, unlike scale, shrinks the layout box too. */}
<span className="flex [zoom:0.78] @md/demo:[zoom:1]">{children}</span>
</div>
{/* The phase joins the name only when the tile is wide enough to hold both. */}
<figcaption className="flex items-baseline justify-center gap-1.5 px-2 pt-1 pb-2 font-mono text-[11px] leading-none @md/demo:border-t @md/demo:border-line @md/demo:px-2.5 @md/demo:py-2 @md/demo:text-meta @md/demo:leading-normal @[8rem]/tile:justify-between">
<span className="text-ink">{name}</span>
<span className="hidden truncate text-muted @[8rem]/tile:inline">{phase}</span>
</figcaption>
</figure>
);
}
export default function Demo() {
const [step, setStep] = useState(0);
const { phase, line } = SCRIPT[step];
useEffect(() => {
const id = setInterval(() => setStep((s) => (s + 1) % SCRIPT.length), 2400);
return () => clearInterval(id);
}, []);
return (
<div className="@container/demo w-full max-w-xl">
<div className="grid grid-cols-4 gap-2 @md/demo:gap-3">
<div className="col-span-full flex animate-enter items-center gap-2.5 rounded-xl bg-surface px-3 py-2 shadow-md @md/demo:gap-3 @md/demo:px-4 @md/demo:py-3">
<AgentShape phase={phase} label={line} size={28} className="text-ink" />
<span aria-hidden key={step} className="min-w-0 flex-1 animate-enter truncate text-body font-medium">
<Shimmer>{line}</Shimmer>
</span>
<span aria-hidden className="font-mono text-meta tabular-nums text-muted">
{String(step + 1).padStart(2, "0")} / {String(SCRIPT.length).padStart(2, "0")}
</span>
</div>
{SCRIPT.map((entry, i) => {
const { name, label, Shape } = phases[entry.phase];
return (
<Tile key={entry.phase} name={name} phase={label.toLowerCase()} index={i + 1}>
<Shape size={36} />
</Tile>
);
})}
</div>
</div>
);
}
