Buchlaunch

'use client';

import { useEffect, useId, useRef, useState } from 'react';
import { cn, prefersReducedMotion, round, useInView, useLocale, useTexts, type Locale } from '@/lib/kit';
import { Button } from '@/components/ui/button';
import { Icon, type IconName } from '@/components/ui/icon';
import { Magnetic, Parallax, Stagger, useScrollProgress } from '@/components/ui/motion';
import { Reveal } from '@/components/ui/reveal';
import { Section, SectionHeader } from '@/components/ui/section';

/*
 * Sections for a book: the launch, a reading sample, the chapters, the
 * pre-order with bonuses and what readers and the press say. The cover is a
 * picture slot, the kit draws nothing in it.
 *
 *   hero      cover that tilts toward the pointer and drifts on scroll, release date, formats and one quote
 *   excerpt   the first pages as a page, a progress line while reading, the rest by email
 *   chapters  the contents with page numbers, each chapter opens with its summary, free ones marked
 *   preorder  format cards, a signed copy, bonuses that stack up and the days until release
 *   reviews   one large quote at a time, reader ratings as bars and short press lines
 */

export type BookLaunchVariant = 'hero' | 'excerpt' | 'chapters' | 'preorder' | 'reviews';

export interface BookFormat {
  id: string;
  label: string;
  /** e.g. "Hardcover, 288 pages" */
  detail?: string;
  price: number;
  icon?: IconName;
  href?: string;
}

export interface BookChapter {
  id: string;
  title: string;
  page: number;
  summary?: string;
  /** Part of the free sample */
  free?: boolean;
}

export interface BookQuote {
  quote: string;
  name: string;
  /** e.g. "Author of ..." or a newspaper */
  role?: string;
  rating?: number;
}

export interface BookLaunchProps {
  variant?: BookLaunchVariant;
  eyebrow?: React.ReactNode;
  title?: React.ReactNode;
  description?: React.ReactNode;
  book: {
    title: string;
    subtitle?: string;
    author: string;
    /** YYYY-MM-DD */
    release?: string;
    pages?: number;
    cover?: React.ReactNode;
  };
  formats?: BookFormat[];
  chapters?: BookChapter[];
  /** excerpt: paragraphs of the sample, the first gets a drop cap */
  excerpt?: { chapter: string; paragraphs: string[] };
  quotes?: BookQuote[];
  /** reviews: count of ratings per star, five first */
  ratings?: number[];
  /** preorder: bonuses for ordering before the release */
  bonuses?: { label: string; value?: string; icon?: IconName }[];
  /** preorder: price of a signed copy on top */
  signedExtra?: number;
  currency?: string;
  onSubmit?: (data: Record<string, string>) => void;
  /** Where the jumps go, sections of the same page by default: #excerpt */
  links?: { excerpt?: string };
  labels?: Partial<Texts>;
  className?: string;
}



const TEXTS = {
  en: {
    out: 'Out on {date}',
    outNow: 'Out now',
    days: '{n} days to go',
    day: '1 day to go',
    order: 'Pre-order now',
    buy: 'Buy now',
    sample: 'Read a sample',
    by: 'by {name}',
    pages: '{n} pages',
    keepReading: 'Read the whole first chapter',
    keepText: 'The full chapter as a PDF, straight to your inbox.',
    email: 'Email',
    emailPh: 'you@example.com',
    send: 'Send me chapter 1',
    sent: 'Chapter 1 is on its way to {e}.',
    invalid: 'Please enter an email address like name@example.com.',
    contents: 'Contents',
    free: 'Free sample',
    page: 'p. {n}',
    format: 'Format',
    signed: 'Signed copy with dedication',
    dedication: 'Name for the dedication',
    dedicationPh: 'For Sam',
    bonuses: 'Included with every pre-order',
    total: 'Total',
    worth: 'worth {v}',
    readers: 'Reader ratings',
    ratingOf: '{r} of 5',
    based: 'from {n} ratings',
    prev: 'Previous quote',
    next: 'Next quote',
    quote: 'Quote {n} of {total}',
    press: 'In the press',
    stars: '{n} stars',
  },
  de: {
    out: 'Erscheint am {date}',
    outNow: 'Jetzt erhältlich',
    days: 'Noch {n} Tage',
    day: 'Noch 1 Tag',
    order: 'Jetzt vorbestellen',
    buy: 'Jetzt kaufen',
    sample: 'Leseprobe lesen',
    by: 'von {name}',
    pages: '{n} Seiten',
    keepReading: 'Das ganze erste Kapitel lesen',
    keepText: 'Das vollständige Kapitel als PDF, direkt in dein Postfach.',
    email: 'E-Mail',
    emailPh: 'du@beispiel.de',
    send: 'Kapitel 1 schicken',
    sent: 'Kapitel 1 ist unterwegs an {e}.',
    invalid: 'Bitte gib eine E-Mail-Adresse wie name@beispiel.de ein.',
    contents: 'Inhalt',
    free: 'Leseprobe',
    page: 'S. {n}',
    format: 'Ausgabe',
    signed: 'Signiert mit Widmung',
    dedication: 'Name für die Widmung',
    dedicationPh: 'Für Sam',
    bonuses: 'Bei jeder Vorbestellung dabei',
    total: 'Gesamt',
    worth: 'Wert {v}',
    readers: 'Bewertungen',
    ratingOf: '{r} von 5',
    based: 'aus {n} Bewertungen',
    prev: 'Vorheriges Zitat',
    next: 'Nächstes Zitat',
    quote: 'Zitat {n} von {total}',
    press: 'In der Presse',
    stars: '{n} Sterne',
  },
};
type Texts = typeof TEXTS.en;

/* ------------------------------------------------------------------ */
/* Helpers                                                             */
/* ------------------------------------------------------------------ */

const TAG: Record<Locale, string> = { en: 'en-US', de: 'de-DE' };
const fill = (s: string, v: Record<string, string | number>) => s.replace(/\{(\w+)\}/g, (_, k) => String(v[k] ?? ''));
const focusRing = 'focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 focus-visible:ring-offset-background';
const fit = '[&>*]:size-full [&_img]:object-cover';
function money(value: number, currency: string, locale: Locale) {
  const whole = Number.isInteger(value);
  return new Intl.NumberFormat(TAG[locale], { style: 'currency', currency, minimumFractionDigits: whole ? 0 : 2, maximumFractionDigits: whole ? 0 : 2 }).format(value);
}
function dateText(iso: string, locale: Locale) {
  const [y, m, d] = iso.split('-').map(Number);
  return new Intl.DateTimeFormat(TAG[locale], { day: 'numeric', month: 'long', year: 'numeric', timeZone: 'UTC' }).format(new Date(Date.UTC(y, m - 1, d)));
}
/** Days until the release, only in the browser. On the server null, the date shows alone. */
function useDaysLeft(iso?: string) {
  const [n, setN] = useState<number | null>(null);
  useEffect(() => {
    if (!iso) return;
    const [y, m, d] = iso.split('-').map(Number);
    const now = new Date();
    const today = Date.UTC(now.getFullYear(), now.getMonth(), now.getDate());
    setN(Math.round((Date.UTC(y, m - 1, d) - today) / 864e5));
  }, [iso]);
  return n;
}

const MOTION_CSS = `
@keyframes kitbook-in{from{opacity:0;transform:translateY(8px)}}
@keyframes kitbook-swap{from{opacity:0;filter:blur(4px);transform:translateY(6px)}}
@keyframes kitbook-quote{from{opacity:0;transform:translateY(14px)}}
@keyframes kitbook-grow{from{transform:scaleX(0)}}
@keyframes kitbook-pop{0%{transform:scale(.5);opacity:0}60%{transform:scale(1.12);opacity:1}100%{transform:scale(1)}}
@media (prefers-reduced-motion:reduce){[class*="kitbook-"],.kitbook-anim{animation:none!important;transition:none!important}}`;

function BookMotion() {
  return (
    <style href="kitbook-motion" precedence="default">
      {MOTION_CSS}
    </style>
  );
}

function Stars({ value, size = 16, className, label }: { value: number; size?: number; className?: string; label?: string }) {
  return (
    <span role="img" aria-label={label} className={cn('inline-flex gap-0.5', className)}>
      {[1, 2, 3, 4, 5].map((i) => (
        <svg key={i} width={size} height={size} viewBox="0 0 24 24" aria-hidden className={i <= Math.round(value) ? 'text-[color-mix(in_oklab,var(--warning)_85%,var(--foreground))]' : 'text-border-strong'}>
          <path fill="currentColor" d="M12 2.8l2.7 5.6 6.1.8-4.5 4.2 1.1 6.1L12 16.6l-5.4 2.9 1.1-6.1-4.5-4.2 6.1-.8z" />
        </svg>
      ))}
    </span>
  );
}

/** The cover in a book shape: spine shade on the left, pages on the right edge, tilts toward a mouse */
function Cover({ cover, title, tilt = true, className }: { cover?: React.ReactNode; title: string; tilt?: boolean; className?: string }) {
  const ref = useRef<HTMLDivElement>(null);
  const move = (e: React.PointerEvent<HTMLDivElement>) => {
    const el = ref.current;
    if (!tilt || !el || e.pointerType !== 'mouse' || prefersReducedMotion()) return;
    const r = el.getBoundingClientRect();
    const x = (e.clientX - r.left) / r.width - 0.5;
    const y = (e.clientY - r.top) / r.height - 0.5;
    el.style.transform = `perspective(1200px) rotateY(${(x * 14).toFixed(2)}deg) rotateX(${(-y * 10).toFixed(2)}deg)`;
    el.style.setProperty('--gx', `${((x + 0.5) * 100).toFixed(1)}%`);
    el.style.setProperty('--gy', `${((y + 0.5) * 100).toFixed(1)}%`);
  };
  const leave = () => {
    if (ref.current) ref.current.style.transform = '';
  };
  return (
    <div onPointerMove={move} onPointerLeave={leave} className={cn('relative', className)}>
      <div ref={ref} className="relative aspect-[2/3] transition-transform duration-500 ease-[var(--ease-kit)] [transform-style:preserve-3d] motion-reduce:transition-none">
        {/* pages behind the cover */}
        <span aria-hidden className="absolute inset-y-[1.2%] -right-[3%] left-[4%] rounded-r-[6px] bg-[repeating-linear-gradient(to_bottom,#f4efe6_0,#f4efe6_2px,#e2dccf_2px,#e2dccf_3px)] shadow-[var(--shadow-md)]" />
        <div className="relative size-full overflow-hidden rounded-[3px_8px_8px_3px] bg-muted shadow-[0_30px_60px_-20px_rgb(0_0_0/0.45),var(--shadow-md)]" data-clip-ok>
          <div className={cn('size-full', fit)} role="img" aria-label={title}>
            {cover}
          </div>
          <span aria-hidden className="absolute inset-y-0 left-0 w-[7%] bg-[linear-gradient(to_right,rgb(0_0_0/0.35),rgb(255_255_255/0.12)_45%,rgb(0_0_0/0.08))]" />
          <span aria-hidden className="pointer-events-none absolute inset-0 bg-[radial-gradient(circle_at_var(--gx,30%)_var(--gy,20%),rgb(255_255_255/0.22),transparent_55%)] mix-blend-soft-light" />
        </div>
      </div>
    </div>
  );
}

function ReleaseChip({ release, t }: { release?: string; t: Texts }) {
  const locale = useLocale();
  const left = useDaysLeft(release);
  if (!release) return null;
  const out = left !== null && left <= 0;
  return (
    <span className="inline-flex min-h-8 flex-wrap items-center gap-x-2 gap-y-0.5 rounded-full border max-sm:rounded-xl border-border bg-card/70 px-3 py-1 text-[13px] text-foreground backdrop-blur">
      <span className="relative flex size-2">
        <span aria-hidden className="absolute inset-0 animate-ping rounded-full bg-primary opacity-60 motion-reduce:animate-none" />
        <span className="relative size-2 rounded-full bg-primary" />
      </span>
      <span className="font-medium">{out ? t.outNow : fill(t.out, { date: dateText(release, locale) })}</span>
      {left !== null && left > 0 && <span className="whitespace-nowrap text-muted-foreground [animation:kitbook-in_.4s_var(--ease-kit)] max-sm:basis-full max-sm:pl-4"><span aria-hidden className="max-sm:hidden">· </span>{left === 1 ? t.day : fill(t.days, { n: left })}</span>}
    </span>
  );
}

/* ------------------------------------------------------------------ */
/* hero                                                                */
/* ------------------------------------------------------------------ */

function Hero({ book, formats = [], quotes = [], links, t }: BookLaunchProps & { t: Texts }) {
  const locale = useLocale();
  const left = useDaysLeft(book.release);
  const preorder = left === null ? !!book.release : left > 0;
  const q = quotes[0];
  return (
    <div className="grid grid-cols-1 items-center gap-12 md:grid-cols-[minmax(0,1fr)_minmax(0,1.1fr)] lg:gap-20">
      <div className="relative mx-auto w-full max-w-[220px] sm:max-w-[280px] md:order-2 md:max-w-[380px]">
        <span aria-hidden data-clip-ok className="absolute inset-x-[-20%] top-[10%] h-[80%] rounded-full bg-[radial-gradient(closest-side,color-mix(in_oklab,var(--primary)_28%,transparent),transparent)] blur-2xl" />
        <Parallax speed={50}>
          <div className="kit-rise [--kit-delay:120ms]">
            <Cover cover={book.cover} title={book.title} />
          </div>
        </Parallax>
      </div>
      <div className="md:order-1">
        <div className="kit-rise">
          <ReleaseChip release={book.release} t={t} />
        </div>
        <h2 className="kit-rise mt-6 text-balance text-h1 font-semibold text-foreground [--kit-delay:60ms]">{book.title}</h2>
        {book.subtitle && <p className="kit-rise mt-4 max-w-[34rem] text-pretty text-lead text-muted-foreground [--kit-delay:120ms]">{book.subtitle}</p>}
        <p className="kit-rise mt-5 text-[15px] text-foreground [--kit-delay:160ms]">
          {fill(t.by, { name: book.author })}
          {book.pages && <span className="text-muted-foreground"> · {fill(t.pages, { n: book.pages })}</span>}
        </p>
        <div className="kit-rise mt-8 flex flex-wrap items-center gap-3 [--kit-delay:220ms] max-sm:flex-col max-sm:items-stretch">
          <Magnetic className="max-sm:flex max-sm:w-full">
            <Button href={formats[0]?.href ?? '#'} icon="arrow-right" className="max-sm:w-full">
              {preorder ? t.order : t.buy}
            </Button>
          </Magnetic>
          <Button href={links?.excerpt ?? '#excerpt'} variant="outline" iconLeft="book-open" className="max-sm:w-full">
            {t.sample}
          </Button>
        </div>
        {formats.length > 0 && (
          <ul className="kit-rise mt-6 flex flex-wrap gap-x-5 gap-y-2 text-[13.5px] text-muted-foreground [--kit-delay:260ms]">
            {formats.map((f) => (
              <li key={f.id} className="inline-flex items-center gap-1.5">
                <Icon name={f.icon ?? 'book-open'} size={15} />
                {f.label}
              </li>
            ))}
          </ul>
        )}
        {q && (
          <Reveal delay={300} className="mt-10 border-l-2 border-primary pl-5">
            <p className="text-pretty text-[17px] italic leading-relaxed text-foreground">{locale === 'de' ? '„' : '“'}{q.quote}{locale === 'de' ? '“' : '”'}</p>
            <p className="mt-2 text-[13.5px] text-muted-foreground">
              {q.name}
              {q.role && `, ${q.role}`}
            </p>
          </Reveal>
        )}
      </div>
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* excerpt                                                             */
/* ------------------------------------------------------------------ */

function Excerpt({ book, excerpt, onSubmit, t }: BookLaunchProps & { t: Texts }) {
  const page = useScrollProgress<HTMLDivElement>({ start: 0.15, end: 0.85 });
  const [email, setEmail] = useState('');
  const [state, setState] = useState<'idle' | 'error' | 'done'>('idle');
  const id = useId();
  const submit = (e: React.FormEvent) => {
    e.preventDefault();
    if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) return setState('error');
    onSubmit?.({ email });
    setState('done');
  };
  if (!excerpt) return null;
  const [first, ...rest] = excerpt.paragraphs;
  return (
    <div id="excerpt" className="grid grid-cols-1 gap-10 lg:grid-cols-[minmax(0,220px)_minmax(0,1fr)] lg:gap-16">
      <aside className="lg:sticky lg:top-8 lg:self-start">
        <div className="flex items-center gap-4 lg:block">
          <div className="w-16 shrink-0 lg:w-36">
            <Cover cover={book.cover} title={book.title} tilt={false} />
          </div>
          <div className="lg:mt-6">
            <p className="text-[15px] font-semibold text-foreground">{book.title}</p>
            <p className="mt-0.5 text-[13.5px] text-muted-foreground">{fill(t.by, { name: book.author })}</p>
            {book.pages && <p className="mt-2 text-[13px] text-muted-foreground">{fill(t.pages, { n: book.pages })}</p>}
          </div>
        </div>
      </aside>
      <div ref={page} className="relative w-full max-w-[720px]">
        <div aria-hidden className="sticky top-0 z-[1] -mx-1 mb-6 h-1 overflow-hidden rounded-full bg-[color-mix(in_oklab,var(--foreground)_12%,transparent)]">
          <div className="kitbook-anim h-full origin-left rounded-full bg-primary" style={{ transform: 'scaleX(var(--kit-progress, 1))' }} />
        </div>
        <article className="rounded-md bg-[color-mix(in_oklab,var(--card)_95%,var(--warning))] px-6 py-10 shadow-[var(--highlight),var(--shadow-md)] ring-1 ring-border sm:px-12 sm:py-14">
          <p className="text-center text-[12px] font-semibold uppercase tracking-[0.14em] text-muted-foreground">{excerpt.chapter}</p>
          <div className="mt-8 space-y-5 text-pretty text-[17px] leading-[1.75] text-foreground sm:text-[18px]">
            <p className="first-letter:float-left first-letter:mr-1.5 first-letter:mt-1 first-letter:text-[3.6em] first-letter:font-semibold first-letter:leading-[0.8] first-letter:text-primary">{first}</p>
            {rest.map((p, i) => (
              <p key={i} className={cn(i === rest.length - 1 && 'relative')}>
                {p}
              </p>
            ))}
          </div>
          <div aria-hidden className="pointer-events-none relative -mt-24 h-24 bg-[linear-gradient(to_bottom,transparent,color-mix(in_oklab,var(--card)_95%,var(--warning)))]" />
          <div className="mt-2 border-t border-border pt-8 text-center">
            <p className="text-[18px] font-semibold text-foreground">{t.keepReading}</p>
            <p className="mt-1.5 text-[14.5px] text-muted-foreground">{t.keepText}</p>
            {state === 'done' ? (
              <p role="status" className="mx-auto mt-6 inline-flex items-center gap-2 rounded-full bg-[color-mix(in_oklab,var(--success)_14%,transparent)] px-4 py-2 text-[14px] font-medium text-success-foreground [animation:kitbook-swap_.45s_var(--ease-kit)]">
                <Icon name="check" size={16} />
                {fill(t.sent, { e: email })}
              </p>
            ) : (
              <form onSubmit={submit} noValidate className="mx-auto mt-6 max-w-[440px] text-left">
                <label htmlFor={id} className="sr-only">
                  {t.email}
                </label>
                <div className="flex flex-col gap-2 sm:flex-row">
                  <input id={id} type="email" value={email} onChange={(e) => { setEmail(e.target.value); if (state === 'error') setState('idle'); }} placeholder={t.emailPh} aria-invalid={state === 'error'} aria-describedby={state === 'error' ? `${id}-e` : undefined} className={cn('h-11 w-full min-w-0 rounded-lg border bg-background px-3 text-[15px] text-foreground placeholder:text-subtle-foreground sm:w-0 sm:flex-1', focusRing, state === 'error' ? 'border-destructive' : 'border-border-strong')} />
                  <Button type="submit" icon="arrow-right">
                    {t.send}
                  </Button>
                </div>
                {state === 'error' && (
                  <p id={`${id}-e`} className="mt-2 text-[13px] text-destructive">
                    {t.invalid}
                  </p>
                )}
              </form>
            )}
          </div>
        </article>
      </div>
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* chapters                                                            */
/* ------------------------------------------------------------------ */

function Chapters({ book, chapters = [], t }: BookLaunchProps & { t: Texts }) {
  const [open, setOpen] = useState<string | null>(chapters.find((c) => c.free)?.id ?? null);
  const base = useId();
  const total = book.pages ?? chapters[chapters.length - 1]?.page ?? 1;
  return (
    <div className="grid grid-cols-1 gap-10 lg:grid-cols-[minmax(0,1fr)_minmax(0,2fr)] lg:gap-16">
      <div className="hidden lg:block">
        <div className="sticky top-8 mx-auto max-w-[260px]">
          <Cover cover={book.cover} title={book.title} />
          <p className="mt-6 text-center text-[13.5px] text-muted-foreground">{fill(t.pages, { n: total })}</p>
        </div>
      </div>
      <div>
        <p className="mb-3 text-[13px] font-medium text-muted-foreground">{t.contents}</p>
        <Stagger as="ol" step={50} className="border-t border-border">
          {chapters.map((c, i) => {
            const on = open === c.id;
            const next = chapters[i + 1]?.page ?? total;
            const share = round(((next - c.page) / total) * 100, 2);
            return (
              <li key={c.id} className="border-b border-border">
                <h3>
                  <button type="button" aria-expanded={on} aria-controls={`${base}-${c.id}`} onClick={() => setOpen(on ? null : c.id)} disabled={!c.summary} className={cn('group grid w-full grid-cols-[2.25rem_minmax(0,1fr)_auto] items-baseline gap-x-3 py-4 text-left sm:grid-cols-[3rem_minmax(0,1fr)_auto]', focusRing, 'focus-visible:ring-inset focus-visible:ring-offset-0')}>
                    <span className="text-[14px] tabular-nums text-muted-foreground">{String(i + 1).padStart(2, '0')}</span>
                    <span className="flex min-w-0 items-baseline gap-3">
                      <span className={cn('text-[16.5px] font-medium leading-snug transition-colors', on ? 'text-foreground' : 'text-foreground/85 group-hover:text-foreground')}>{c.title}</span>
                      {c.free && <span className="shrink-0 rounded-full bg-[color-mix(in_oklab,var(--primary)_14%,transparent)] px-2 py-0.5 text-[11.5px] font-semibold text-foreground">{t.free}</span>}
                      <span aria-hidden className="hidden h-px min-w-6 flex-1 translate-y-[-4px] border-b border-dotted border-border-strong sm:block" />
                    </span>
                    <span className="flex items-center gap-3 text-[13.5px] tabular-nums text-muted-foreground">
                      {fill(t.page, { n: c.page })}
                      {c.summary && <Icon name="chevron-down" size={16} className={cn('transition-transform duration-300', on && 'rotate-180')} />}
                    </span>
                  </button>
                </h3>
                <div id={`${base}-${c.id}`} hidden={!on} className="pb-5 pl-[3rem] sm:pl-[3.75rem]">
                  {on && (
                    <div className="[animation:kitbook-swap_.45s_var(--ease-kit)]">
                      <p className="max-w-[40rem] text-pretty text-[15px] leading-relaxed text-muted-foreground">{c.summary}</p>
                      <div className="mt-4 flex items-center gap-3">
                        <div aria-hidden className="h-1 w-full max-w-[200px] overflow-hidden rounded-full bg-[color-mix(in_oklab,var(--foreground)_12%,transparent)]">
                          <div className="h-full origin-left rounded-full bg-primary [animation:kitbook-grow_.8s_var(--ease-kit)]" style={{ width: `${Math.min(100, Math.max(4, share * 4))}%` }} />
                        </div>
                        <span className="text-[12.5px] tabular-nums text-muted-foreground">{fill(t.pages, { n: next - c.page })}</span>
                      </div>
                    </div>
                  )}
                </div>
              </li>
            );
          })}
        </Stagger>
      </div>
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* preorder                                                            */
/* ------------------------------------------------------------------ */

function Preorder({ book, formats = [], bonuses = [], signedExtra, currency = 'EUR', t }: BookLaunchProps & { t: Texts }) {
  const locale = useLocale();
  const [fmt, setFmt] = useState(formats[0]?.id ?? '');
  const [signed, setSigned] = useState(false);
  const [name, setName] = useState('');
  const base = useId();
  const f = formats.find((x) => x.id === fmt) ?? formats[0];
  const physical = f?.icon === 'book-open' || f?.id === 'hardcover' || f?.id === 'paperback';
  const total = (f?.price ?? 0) + (signed && physical && signedExtra ? signedExtra : 0);
  const [ref, inView] = useInView<HTMLUListElement>();
  const left = useDaysLeft(book.release);
  return (
    <div className="grid grid-cols-1 gap-8 lg:grid-cols-[minmax(0,1.2fr)_minmax(0,1fr)] lg:gap-12">
      <div className="kit-card p-6 sm:p-8">
        <div className="flex flex-col items-start gap-3 sm:flex-row sm:items-center sm:justify-between">
          <p className="text-[15px] font-semibold text-foreground">{t.format}</p>
          <ReleaseChip release={book.release} t={t} />
        </div>
        <div role="radiogroup" aria-label={t.format} className="mt-5 grid grid-cols-1 gap-3 sm:grid-cols-3">
          {formats.map((x) => {
            const on = x.id === f?.id;
            return (
              <label key={x.id} className={cn('relative flex cursor-pointer flex-col rounded-xl border p-4 transition-[border-color,background-color,transform] duration-300 has-[:focus-visible]:ring-2 has-[:focus-visible]:ring-ring max-sm:flex-row max-sm:items-center max-sm:gap-3', on ? 'border-primary bg-[color-mix(in_oklab,var(--primary)_8%,var(--card))]' : 'border-border hover:-translate-y-0.5 hover:border-border-strong')}>
                <input type="radio" name={`${base}-f`} checked={on} onChange={() => setFmt(x.id)} className="sr-only" />
                <Icon name={x.icon ?? 'book-open'} size={20} className={on ? 'text-primary' : 'text-muted-foreground'} />
                <span className="mt-3 block min-w-0 flex-1 max-sm:mt-0">
                  <span className="block text-[15px] font-semibold text-foreground">{x.label}</span>
                  {x.detail && <span className="block text-[12.5px] text-muted-foreground">{x.detail}</span>}
                </span>
                <span className="mt-3 text-[16px] font-semibold tabular-nums text-foreground max-sm:mt-0">{money(x.price, currency, locale)}</span>
              </label>
            );
          })}
        </div>
        {signedExtra !== undefined && (
          <div className={cn('mt-5 rounded-xl border border-border p-4 transition-opacity', !physical && 'opacity-50')}>
            <label className="flex cursor-pointer items-center justify-between gap-4">
              <span className="flex items-center gap-3">
                <Icon name="edit" size={18} className="text-muted-foreground" />
                <span className="text-[14.5px] font-medium text-foreground">{t.signed}</span>
              </span>
              <span className="flex items-center gap-3">
                <span className="whitespace-nowrap text-[14px] tabular-nums text-muted-foreground">+{money(signedExtra, currency, locale)}</span>
                <input type="checkbox" role="switch" checked={signed && physical} disabled={!physical} onChange={(e) => setSigned(e.target.checked)} className="peer sr-only" />
                <span aria-hidden className={cn('relative h-6 w-10 rounded-full transition-colors peer-focus-visible:ring-2 peer-focus-visible:ring-ring', signed && physical ? 'bg-primary' : 'bg-border-strong')}>
                  <span className={cn('absolute left-0.5 top-0.5 size-5 rounded-full bg-white shadow transition-transform duration-300 ease-[var(--ease-kit)]', signed && physical && 'translate-x-4')} />
                </span>
              </span>
            </label>
            {signed && physical && (
              <div className="mt-4 [animation:kitbook-swap_.4s_var(--ease-kit)]">
                <label htmlFor={`${base}-d`} className="mb-2 block text-[13.5px] font-medium text-foreground">
                  {t.dedication}
                </label>
                <input id={`${base}-d`} value={name} onChange={(e) => setName(e.target.value)} placeholder={t.dedicationPh} className={cn('h-11 w-full rounded-lg border border-border-strong bg-background px-3 text-[15px] text-foreground placeholder:text-subtle-foreground', focusRing)} />
              </div>
            )}
          </div>
        )}
        <div className="mt-6 flex flex-col gap-4 border-t border-border pt-6 sm:flex-row sm:items-center sm:justify-between">
          <div>
            <p className="text-[13px] text-muted-foreground">{t.total}</p>
            <p key={total} className="text-[30px] font-semibold leading-none tracking-[-0.02em] tabular-nums text-foreground [animation:kitbook-swap_.4s_var(--ease-kit)]">
              {money(total, currency, locale)}
            </p>
          </div>
          <Button href={f?.href ?? '#'} icon="arrow-right" size="lg" className="max-sm:w-full">
            {left !== null && left <= 0 ? t.buy : t.order}
          </Button>
        </div>
      </div>
      {bonuses.length > 0 && (
        <div className="relative overflow-hidden rounded-xl border border-border bg-surface p-6 sm:p-8">
          <p className="text-[15px] font-semibold text-foreground">{t.bonuses}</p>
          <ul ref={ref} className="relative z-[1] mt-5 grid gap-3">
            {bonuses.map((b, i) => (
              <li key={b.label} className="flex items-center gap-4 rounded-xl border border-border bg-card p-4 transition-[transform,opacity] duration-700 ease-[var(--ease-kit)] motion-reduce:transition-none" style={{ transform: inView ? 'none' : `translateY(${16 + i * 10}px) scale(0.97)`, opacity: inView ? 1 : 0, transitionDelay: inView ? `${i * 120}ms` : '0ms' }}>
                <span className="flex size-10 shrink-0 items-center justify-center rounded-lg bg-[color-mix(in_oklab,var(--primary)_14%,transparent)] text-primary">
                  <Icon name={b.icon ?? 'gift'} size={19} />
                </span>
                <span className="min-w-0 flex-1">
                  <span className="block text-[14.5px] font-medium text-foreground">{b.label}</span>
                  {b.value && <span className="mt-0.5 block text-[13px] text-muted-foreground sm:hidden">{fill(t.worth, { v: b.value })}</span>}
                </span>
                {b.value && <span className="shrink-0 text-[13px] text-muted-foreground max-sm:hidden">{fill(t.worth, { v: b.value })}</span>}
              </li>
            ))}
          </ul>
          <div aria-hidden data-clip-ok className="pointer-events-none absolute -bottom-24 -right-12 w-36 rotate-12 opacity-80 max-lg:hidden">
            <Cover cover={book.cover} title={book.title} tilt={false} />
          </div>
        </div>
      )}
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* reviews                                                             */
/* ------------------------------------------------------------------ */

function Reviews({ quotes = [], ratings = [], t }: BookLaunchProps & { t: Texts }) {
  const locale = useLocale();
  const big = quotes.filter((q) => q.rating === undefined || q.quote.length > 90);
  const small = quotes.filter((q) => !big.includes(q));
  const [i, setI] = useState(0);
  const [paused, setPaused] = useState(false);
  const count = ratings.reduce((a, b) => a + b, 0);
  const avg = count ? ratings.reduce((a, n, k) => a + n * (5 - k), 0) / count : 0;
  const [ref, inView] = useInView<HTMLDivElement>();
  useEffect(() => {
    if (paused || big.length < 2 || prefersReducedMotion()) return;
    const id = window.setInterval(() => setI((v) => (v + 1) % big.length), 7000);
    return () => window.clearInterval(id);
  }, [paused, big.length]);
  const q = big[i % Math.max(1, big.length)];
  const nf = new Intl.NumberFormat(TAG[locale], { maximumFractionDigits: 1, minimumFractionDigits: 1 });
  return (
    <div className="grid grid-cols-1 gap-6 lg:grid-cols-[minmax(0,1.6fr)_minmax(0,1fr)] lg:gap-8">
      {q && (
        <figure onPointerEnter={() => setPaused(true)} onPointerLeave={() => setPaused(false)} onFocus={() => setPaused(true)} onBlur={() => setPaused(false)} className="kit-card relative flex min-h-[300px] flex-col justify-between overflow-hidden p-8 sm:p-10">
          <Icon name="quote" size={56} className="absolute right-8 top-8 text-[color-mix(in_oklab,var(--primary)_22%,transparent)]" />
          <blockquote key={i} aria-live="polite" className="relative max-w-[40rem] text-balance pr-12 text-[22px] font-medium leading-[1.4] tracking-[-0.01em] text-foreground [animation:kitbook-quote_.6s_var(--ease-kit)] sm:text-[26px]">
            {q.quote}
          </blockquote>
          <figcaption key={`c${i}`} className="relative mt-8 flex flex-wrap items-end justify-between gap-4 [animation:kitbook-in_.5s_var(--ease-kit)_both] [animation-delay:120ms]">
            <span>
              <span className="block text-[15px] font-semibold text-foreground">{q.name}</span>
              {q.role && <span className="block text-[13.5px] text-muted-foreground">{q.role}</span>}
            </span>
            {big.length > 1 && (
              <span className="flex items-center gap-3">
                <span className="text-[13px] tabular-nums text-muted-foreground">{fill(t.quote, { n: i + 1, total: big.length })}</span>
                <button type="button" aria-label={t.prev} onClick={() => setI((v) => (v - 1 + big.length) % big.length)} className={cn('flex size-11 items-center justify-center rounded-full border border-border text-foreground transition-colors hover:bg-accent', focusRing)}>
                  <Icon name="arrow-left" size={18} />
                </button>
                <button type="button" aria-label={t.next} onClick={() => setI((v) => (v + 1) % big.length)} className={cn('flex size-11 items-center justify-center rounded-full border border-border text-foreground transition-colors hover:bg-accent', focusRing)}>
                  <Icon name="arrow-right" size={18} />
                </button>
              </span>
            )}
          </figcaption>
          {big.length > 1 && !paused && (
            <span aria-hidden key={`p${i}`} className="absolute inset-x-0 bottom-0 h-0.5 origin-left bg-primary animate-kit-progress [--kit-duration:7s] motion-reduce:hidden" />
          )}
        </figure>
      )}
      {count > 0 && (
          <div ref={ref} className="kit-card p-6">
            <p className="text-[13px] font-medium text-muted-foreground">{t.readers}</p>
            <div className="mt-2 flex items-end gap-3">
              <span className="text-[44px] font-semibold leading-none tracking-[-0.03em] tabular-nums text-foreground">{nf.format(avg)}</span>
              <span className="pb-1">
                <Stars value={avg} label={fill(t.ratingOf, { r: nf.format(avg) })} />
                <span className="block text-[12.5px] text-muted-foreground">{fill(t.based, { n: new Intl.NumberFormat(TAG[locale]).format(count) })}</span>
              </span>
            </div>
            <ul className="mt-5 grid gap-2">
              {ratings.map((n, k) => (
                <li key={k} className="grid grid-cols-[2.5rem_minmax(0,1fr)_2.75rem] items-center gap-3 text-[13px] tabular-nums text-muted-foreground">
                  <span aria-label={fill(t.stars, { n: 5 - k })}>{5 - k} ★</span>
                  <span className="h-2 overflow-hidden rounded-full bg-[color-mix(in_oklab,var(--foreground)_12%,transparent)]">
                    <span className="block h-full origin-left rounded-full bg-[color-mix(in_oklab,var(--warning)_85%,var(--foreground))] transition-transform duration-1000 ease-[var(--ease-kit)] motion-reduce:transition-none" style={{ transform: `scaleX(${inView ? round(n / Math.max(...ratings), 3) : 0})`, transitionDelay: inView ? `${k * 90}ms` : '0ms' }} />
                  </span>
                  <span className="text-right">{Math.round((n / count) * 100)}{locale === 'de' ? ' %' : '%'}</span>
                </li>
              ))}
            </ul>
          </div>
        )}
        {small.length > 0 && (
          <div className="lg:col-span-2">
            <p className="mb-3 text-[13px] font-medium text-muted-foreground">{t.press}</p>
            <Stagger as="ul" step={80} className="grid grid-cols-1 gap-3 md:grid-cols-3">
              {small.map((s) => (
                <li key={s.name} className="rounded-xl border border-border p-4">
                  {s.rating !== undefined && <Stars value={s.rating} size={14} label={fill(t.ratingOf, { r: s.rating })} />}
                  <p className="mt-2 text-pretty text-[14.5px] leading-relaxed text-foreground">{s.quote}</p>
                  <p className="mt-2 text-[13px] font-medium text-muted-foreground">{s.name}</p>
                </li>
              ))}
            </Stagger>
          </div>
        )}
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* BookLaunch                                                          */
/* ------------------------------------------------------------------ */

/**
 * Sections for a book launch.
 *   hero      tilting cover, release date with days to go, formats and one quote
 *   excerpt   the first pages with a reading line, the rest by email
 *   chapters  the contents, chapters open with their summary
 *   preorder  formats, signed copy, bonuses and the total
 *   reviews   rotating quotes, reader ratings and press lines
 */
export function BookLaunch(props: BookLaunchProps) {
  const { variant = 'hero', eyebrow, title, description, labels, className } = props;
  const t = useTexts(TEXTS, labels);
  const body = (() => {
    switch (variant) {
      case 'excerpt':
        return <Excerpt {...props} t={t} />;
      case 'chapters':
        return <Chapters {...props} t={t} />;
      case 'preorder':
        return <Preorder {...props} t={t} />;
      case 'reviews':
        return <Reviews {...props} t={t} />;
      default:
        return <Hero {...props} t={t} />;
    }
  })();
  return (
    <Section className={cn('overflow-clip', className)} background={variant === 'hero' ? 'glow' : variant === 'excerpt' ? 'surface' : 'default'}>
      <BookMotion />
      {title && variant !== 'hero' ? <SectionHeader eyebrow={eyebrow} title={title} description={description} /> : null}
      {body}
    </Section>
  );
}