Features 7

"use client";

import { useCallback, useEffect, useState } from "react";
import { motion, useInView, useReducedMotion } from "motion/react";
import { defaultSpring, motionViewport } from "@/lib/motion-tokens";
import { cn } from "@/lib/utils";
import { SectionShell, ContentRail } from "@/components/layout-contract";

const capabilities = [
	{ id: "motion", label: "Motion docs", stat: "40", unit: "live patterns" },
	{ id: "cli", label: "Registry CLI", stat: "1", unit: "shadcn-native path" },
	{ id: "pro", label: "Pro catalog", stat: "∞", unit: "lifetime updates" },
	{ id: "prompt", label: "Copy prompt", stat: "✓", unit: "per block page" },
	{ id: "preview", label: "Preview live", stat: "0", unit: "install risk" },
];

const CYCLE_MS = 3600;

function WitnessCapabilityRow({
	item,
	isActive,
	reduceMotion,
	onSelect,
}: {
	item: (typeof capabilities)[number];
	isActive: boolean;
	reduceMotion: boolean;
	onSelect: () => void;
}) {
	return (
		<motion.button
			animate={
				reduceMotion
					? undefined
					: {
							opacity: isActive ? 1 : 0.42,
							filter: isActive ? "blur(0px)" : "blur(1px)",
						}
			}
			aria-label={item.label}
			aria-pressed={isActive}
			className={cn(
				"relative flex w-full min-h-12 items-center gap-3 border-l-2 py-2.5 text-left transition-[border-color,transform] active:scale-[0.98]",
				"after:absolute after:top-1/2 after:left-8 after:size-10 after:-translate-y-1/2",
				isActive ? "border-primary pl-4 md:pl-5" : "border-transparent pl-[calc(1rem+2px)] md:pl-[calc(1.25rem+2px)]",
			)}
			onClick={onSelect}
			transition={{ type: "spring", duration: 0.32, bounce: 0 }}
			type="button"
		>
			<span
				className={cn(
					"shrink-0 font-medium text-lg tabular-nums tracking-tight md:text-xl",
					isActive ? "text-primary" : "text-muted-foreground",
				)}
			>
				{item.stat}
			</span>

			<motion.div
				animate={
					isActive
						? { opacity: 1, width: "auto", filter: "blur(0px)" }
						: { opacity: 0.65, width: "auto", filter: "blur(0px)" }
				}
				className="min-w-0"
				initial={false}
				transition={{ type: "spring", duration: 0.32, bounce: 0 }}
			>
				<p className={cn("font-medium text-sm", isActive && "text-foreground")}>
					{item.label}
				</p>
				<motion.p
					animate={
						isActive
							? { opacity: 1, height: "auto" }
							: { opacity: 0, height: 0 }
					}
					className="overflow-hidden text-muted-foreground text-xs"
					initial={false}
					transition={{ type: "spring", duration: 0.3, bounce: 0 }}
				>
					{item.unit}
				</motion.p>
			</motion.div>
		</motion.button>
	);
}

export function FeaturesWitnessStackSection() {
	const reduceMotion = useReducedMotion();
	const [rootNode, setRootNode] = useState<HTMLElement | null>(null);
	const isInView = useInView({ current: rootNode }, { ...motionViewport, amount: 0.35 });
	const [active, setActive] = useState(0);
	const [cycleActive, setCycleActive] = useState(false);

	useEffect(() => {
		if (!isInView || reduceMotion) return;
		setCycleActive(true);
	}, [isInView, reduceMotion]);

	useEffect(() => {
		if (!cycleActive || reduceMotion) return;
		const timer = setInterval(() => {
			setActive((current) => (current + 1) % capabilities.length);
		}, CYCLE_MS);
		return () => clearInterval(timer);
	}, [cycleActive, reduceMotion]);

	const selectItem = useCallback((index: number) => {
		setActive(index);
		setCycleActive(false);
		setTimeout(() => setCycleActive(true), CYCLE_MS);
	}, []);

	return (
		<SectionShell spacingMode="section" className="bg-background" ref={setRootNode}>
			<ContentRail maxWidth="max-w-5xl" className="grid gap-8 md:grid-cols-[minmax(0,1fr)_minmax(0,18rem)] md:items-start md:gap-12 lg:gap-16">
				<motion.div
					className="max-w-md space-y-2 md:pt-2"
					initial={reduceMotion ? false : { opacity: 0, y: 8, filter: "blur(4px)" }}
					transition={defaultSpring}
					viewport={motionViewport}
					whileInView={reduceMotion ? undefined : { opacity: 1, y: 0, filter: "blur(0px)" }}
				>
					<p className="font-medium text-primary text-xs uppercase tracking-[0.22em]">
						Proof
					</p>
					<h2 className="text-balance font-medium text-2xl tracking-tight md:text-4xl">
						Built for install workflows
					</h2>
					<p className="text-pretty text-muted-foreground text-sm leading-relaxed md:text-base">
						Witness list with accent bar — same language as logo-cloud-15, applied to
						registry capabilities instead of brand marks.
					</p>
				</motion.div>

				<motion.ul
					aria-label="Registry capabilities"
					className="flex flex-col gap-1"
					initial={reduceMotion ? false : { opacity: 0, y: 10 }}
					transition={{ ...defaultSpring, delay: 0.06 }}
					viewport={motionViewport}
					whileInView={reduceMotion ? undefined : { opacity: 1, y: 0 }}
				>
					{capabilities.map((item, index) => (
						<li key={item.id}>
							<WitnessCapabilityRow
								isActive={active === index}
								item={item}
								onSelect={() => selectItem(index)}
								reduceMotion={!!reduceMotion}
							/>
						</li>
					))}
				</motion.ul>
			</ContentRail>
		</SectionShell>
	);
}