Bewerbungsformular

'use client';

import { useId, useRef, useState } from 'react';
import { cn, useLocale, useTexts } from '@/lib/kit';
import { Button } from '@/components/ui/button';
import { Icon, type IconName } from '@/components/ui/icon';
import { Input } from '@/components/ui/input';
import { Textarea } from '@/components/ui/textarea';
import { Checkbox } from '@/components/ui/checkbox';
import { FileUpload, type UploadItem } from '@/components/ui/file-upload';
import { DateInput } from '@/components/ui/date-input';
import { Reveal } from '@/components/ui/reveal';
import { Section } from '@/components/ui/section';
import { Stagger } from '@/components/ui/motion';
import { ChipGroup, DonePanel, ErrorSummary, FlowHead, isEmail, isPhone, Unfold, useFocusFirstError, type DoneStep, summaryOf, useFormState } from '@/components/ui/form-flow';

/*
 * Applying for a job, a shift or a programme. Files are checked on the way
 * in, the privacy note says how long data is kept, and every send names what
 * is missing and focuses it. Sends everything to `onSubmit`, files as File
 * objects in `files`.
 *
 *   job            a full application beside the role, CV and letter as files or written
 *   quick-apply    a minute on the phone, days and shifts as chips, CV optional
 *   guided-letter  three short prompts become a letter, the preview builds beside them
 *   eligibility    three yes or no questions first, the form opens when they fit
 */

export type ApplicationFormVariant = 'job' | 'quick-apply' | 'guided-letter' | 'eligibility';

export interface ApplicationRole {
  title: string;
  team?: string;
  location?: string;
  type?: string;
  salary?: string;
  /** Short lines under the title, e.g. what the role does */
  points?: string[];
}

export interface ApplicationPrompt {
  id: string;
  title: string;
  hint?: string;
  /** Most words for this part */
  words?: number;
}

export interface EligibilityQuestion {
  id: string;
  title: string;
  hint?: string;
  /** The answer that fits, default yes */
  fits?: 'yes' | 'no';
  /** What to show when the answer does not fit */
  explain?: string;
}

export interface ApplicationFormProps {
  variant?: ApplicationFormVariant;
  eyebrow?: React.ReactNode;
  title?: React.ReactNode;
  description?: React.ReactNode;
  role?: ApplicationRole;
  /** quick-apply: days and shifts to pick */
  days?: string[];
  shifts?: string[];
  /** guided-letter: the prompts */
  prompts?: ApplicationPrompt[];
  /** eligibility: the questions before the form */
  checks?: EligibilityQuestion[];
  /** How long applications are kept, shown in the privacy note, e.g. "six months" */
  retention?: string;
  /** Link to the privacy policy */
  privacyHref?: string;
  today?: string;
  steps?: DoneStep[];
  submitLabel?: string;
  done?: { title: string; text?: string };
  onSubmit?: (data: Record<string, unknown> & { files?: File[] }) => void;
  labels?: Partial<Texts>;
  className?: string;
}

const TEXTS = {
  en: {
    you: 'About you',
    firstName: 'First name',
    lastName: 'Last name',
    name: 'Name',
    nameNeeded: 'Please tell us your name so we know who applies.',
    email: 'Email',
    emailNeeded: 'This address looks incomplete. Please use a form like name@example.com so our answer reaches you.',
    phone: 'Phone',
    phoneNeeded: 'Please add a number with area code, we call back within two days.',
    documents: 'Documents',
    cv: 'CV',
    cvHint: 'PDF up to 10 MB',
    cvNeeded: 'Please add your CV as a PDF, it is the one document we need.',
    letter: 'Cover letter',
    letterUpload: 'Upload a file',
    letterWrite: 'Write it here',
    letterPlaceholder: 'A few lines on why this role and why you',
    optional: 'optional',
    more: 'A few more things',
    start: 'Earliest start',
    salary: 'Salary expectation per year',
    links: 'Portfolio or profile',
    linksHint: 'A link to your work, if you have one',
    privacy: 'I agree that my application is stored and read for this role.',
    privacyHint: 'We keep it for {r} and delete it after that, unless you allow more.',
    privacyLink: 'Privacy policy',
    retention: 'six months',
    privacyNeeded: 'Please agree so we are allowed to read your application.',
    pool: 'Keep me in mind for other roles for one year',
    send: 'Send application',
    role: 'The role',
    days: 'Which days suit you?',
    daysNeeded: 'Please choose at least one day, so we can plan you in.',
    shifts: 'Which shifts?',
    shiftsNeeded: 'Please choose at least one shift.',
    cvOptional: 'CV, if you have one',
    quickNote: 'Takes about a minute. We call you back within two days.',
    words: '{n} of {max} words',
    tooLong: '{n} words over, please shorten it a little.',
    promptNeeded: 'Please write a few words here, it is part of the letter.',
    preview: 'Your letter',
    previewEmpty: 'Your answers become a letter here as you write.',
    greeting: 'Dear hiring team,',
    closing: 'Kind regards',
    check: 'Before you start',
    checkText: 'Three questions to see if this programme fits you.',
    yes: 'Yes',
    no: 'No',
    fitsTitle: 'You fit, welcome to apply',
    fitsText: 'The application opens below.',
    notYetTitle: 'This round is not the right one yet',
    notYetText: 'Change an answer if you chose by mistake.',
    motivation: 'Why do you want to take part?',
    motivationNeeded: 'Please tell us in a few sentences why, it is what the jury reads first.',
    doneTitle: 'Thank you, your application has arrived',
    doneText: 'You get a confirmation by email. We answer every application within two weeks.',
    again: 'Back to the start',
  },
  de: {
    you: 'Zu dir',
    firstName: 'Vorname',
    lastName: 'Nachname',
    name: 'Name',
    nameNeeded: 'Bitte nenne uns deinen Namen, damit wir wissen, wer sich bewirbt.',
    email: 'E-Mail',
    emailNeeded: 'Diese Adresse sieht unvollständig aus. Bitte nutze die Form name@beispiel.de, damit unsere Antwort dich erreicht.',
    phone: 'Telefon',
    phoneNeeded: 'Bitte gib eine Nummer mit Vorwahl an, wir rufen innerhalb von zwei Tagen zurück.',
    documents: 'Unterlagen',
    cv: 'Lebenslauf',
    cvHint: 'PDF bis 10 MB',
    cvNeeded: 'Bitte füge deinen Lebenslauf als PDF hinzu, nur diese Unterlage brauchen wir.',
    letter: 'Anschreiben',
    letterUpload: 'Datei hochladen',
    letterWrite: 'Hier schreiben',
    letterPlaceholder: 'Ein paar Zeilen, warum diese Stelle und warum du',
    optional: 'optional',
    more: 'Noch ein paar Dinge',
    start: 'Frühester Start',
    salary: 'Gehaltswunsch pro Jahr',
    links: 'Portfolio oder Profil',
    linksHint: 'Ein Link zu deiner Arbeit, falls vorhanden',
    privacy: 'Ich bin einverstanden, dass meine Bewerbung für diese Stelle gespeichert und gelesen wird.',
    privacyHint: 'Wir bewahren sie {r} auf und löschen sie danach, außer du erlaubst mehr.',
    privacyLink: 'Datenschutzerklärung',
    retention: 'sechs Monate',
    privacyNeeded: 'Bitte stimme zu, damit wir deine Bewerbung lesen dürfen.',
    pool: 'Für andere Stellen ein Jahr lang an mich denken',
    send: 'Bewerbung senden',
    role: 'Die Stelle',
    days: 'Welche Tage passen dir?',
    daysNeeded: 'Bitte wähle mindestens einen Tag, damit wir dich einplanen können.',
    shifts: 'Welche Schichten?',
    shiftsNeeded: 'Bitte wähle mindestens eine Schicht.',
    cvOptional: 'Lebenslauf, falls vorhanden',
    quickNote: 'Dauert etwa eine Minute. Wir rufen innerhalb von zwei Tagen zurück.',
    words: '{n} von {max} Wörtern',
    tooLong: '{n} Wörter zu viel, bitte kürze ein wenig.',
    promptNeeded: 'Bitte schreib hier ein paar Worte, sie gehören zum Anschreiben.',
    preview: 'Dein Anschreiben',
    previewEmpty: 'Aus deinen Antworten entsteht hier beim Schreiben ein Anschreiben.',
    greeting: 'Liebes Team,',
    closing: 'Viele Grüße',
    check: 'Bevor du startest',
    checkText: 'Drei Fragen, ob das Programm zu dir passt.',
    yes: 'Ja',
    no: 'Nein',
    fitsTitle: 'Du passt, bewirb dich gern',
    fitsText: 'Die Bewerbung öffnet sich darunter.',
    notYetTitle: 'Diese Runde passt noch nicht',
    notYetText: 'Ändere eine Antwort, falls du dich verklickt hast.',
    motivation: 'Warum möchtest du teilnehmen?',
    motivationNeeded: 'Bitte schreib in ein paar Sätzen, warum, das liest die Jury zuerst.',
    doneTitle: 'Danke, deine Bewerbung ist angekommen',
    doneText: 'Du bekommst eine Bestätigung per E-Mail. Wir antworten auf jede Bewerbung innerhalb von zwei Wochen.',
    again: 'Zurück zum Anfang',
  },
};

type Texts = (typeof TEXTS)['en'];

/** A label with the required star in the kit colour */
function Req({ children }: { children: React.ReactNode }) {
  return (
    <>
      {children}
      <span aria-hidden className="ms-0.5 text-[color-mix(in_oklab,var(--destructive)_85%,var(--foreground))]">
        *
      </span>
    </>
  );
}

const asItems = (files: File[], prefix: string): UploadItem[] => files.map((f, i) => ({ id: `${prefix}-${i}-${f.name}`, name: f.name, size: f.size, status: 'done' }));

function Done({ p, t, onAgain, className }: { p: ApplicationFormProps; t: Texts; onAgain: () => void; className?: string }) {
  return (
    <div className={cn('kit-card mx-auto p-6 sm:p-10', className)}>
      <DonePanel
        title={p.done?.title ?? t.doneTitle}
        text={p.done?.text ?? t.doneText}
        steps={p.steps}
        actions={
          <Button variant="outline" iconLeft="rotate-ccw" onClick={onAgain}>
            {t.again}
          </Button>
        }
      />
    </div>
  );
}

function Privacy({ id, p, t, f, value, set }: { id: string; p: ApplicationFormProps; t: Texts; f: ReturnType<typeof useFormState>; value: boolean; set: (v: boolean) => void }) {
  return (
    <div>
      <Checkbox
        id={`${id}-privacy`}
        label={t.privacy}
        description={
          <>
            {t.privacyHint.replace('{r}', p.retention ?? t.retention)}{' '}
            {p.privacyHref && (
              <a href={p.privacyHref} className="font-medium text-foreground underline underline-offset-4 hover:text-[color-mix(in_oklab,var(--primary)_80%,var(--foreground))]">
                {t.privacyLink}
              </a>
            )}
          </>
        }
        checked={value}
        onChange={(e) => (set(e.target.checked), f.clear('privacy'))}
        error={f.errors.privacy}
      />
    </div>
  );
}

function RoleCard({ role, t }: { role: ApplicationRole; t: Texts }) {
  const facts: [IconName, string | undefined][] = [
    ['map-pin', role.location],
    ['clock', role.type],
    ['users', role.team],
    ['coins', role.salary],
  ];
  return (
    <div className="kit-card overflow-hidden">
      <div className="border-b border-border bg-surface px-6 py-5">
        <p className="text-[12.5px] font-medium text-muted-foreground">{t.role}</p>
        <p className="mt-1 text-[19px] font-semibold leading-snug tracking-[-0.02em] text-foreground">{role.title}</p>
      </div>
      <ul className="grid gap-3 px-6 py-5">
        {facts
          .filter(([, v]) => v)
          .map(([icon, v]) => (
            <li key={icon} className="flex items-center gap-3 text-[14px] text-foreground">
              <Icon name={icon} size={16} className="shrink-0 text-muted-foreground" />
              {v}
            </li>
          ))}
      </ul>
      {role.points && role.points.length > 0 && (
        <Stagger step={80} as="ul" className="grid gap-2.5 border-t border-border px-6 py-5">
          {role.points.map((x) => (
            <li key={x} className="flex items-start gap-2.5 text-[13.5px] leading-snug text-muted-foreground">
              <Icon name="check" size={14} className="mt-0.5 shrink-0 text-success" />
              {x}
            </li>
          ))}
        </Stagger>
      )}
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* job                                                                 */
/* ------------------------------------------------------------------ */

function Job({ p, t }: { p: ApplicationFormProps; t: Texts }) {
  const id = useId();
  const f = useFormState();
  const [v, setV] = useState({ first: '', last: '', email: '', phone: '', salary: '', link: '', letter: '' });
  const [start, setStart] = useState<string | null>(null);
  const [cv, setCv] = useState<File[]>([]);
  const [letterFile, setLetterFile] = useState<File[]>([]);
  const [letterMode, setLetterMode] = useState<'upload' | 'write'>('write');
  const [privacy, setPrivacy] = useState(false);
  const [pool, setPool] = useState(false);
  const formRef = useRef<HTMLFormElement>(null);
  const summaryRef = useRef<HTMLDivElement>(null);
  useFocusFirstError(formRef, f.attempt, summaryRef);
  const set = (k: keyof typeof v) => (e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>) => (setV((x) => ({ ...x, [k]: e.target.value })), f.clear(k));
  const summary = summaryOf(f.errors, [
    ['first', `${id}-first`, t.firstName],
    ['email', `${id}-email`, t.email],
    ['cv', `${id}-cv`, t.cv],
    ['privacy', `${id}-privacy`, t.privacyLink],
  ]);
  if (f.done) return <Done p={p} t={t} onAgain={() => (setCv([]), setPrivacy(false), f.setDone(false))} className="max-w-[48rem]" />;
  return (
    <div className="grid grid-cols-1 gap-8 lg:grid-cols-[19rem_minmax(0,1fr)] lg:gap-10">
      {p.role && (
        <Reveal effect="rise" className="lg:sticky lg:top-24 lg:self-start">
          <RoleCard role={p.role} t={t} />
        </Reveal>
      )}
      <Reveal effect="rise" delay={80} className="min-w-0">
        <form
          ref={formRef}
          noValidate
          className="kit-card grid gap-8 p-6 sm:p-8"
          onSubmit={(e) => {
            e.preventDefault();
            const found: Record<string, string> = {};
            if (!v.first.trim()) found.first = t.nameNeeded;
            if (!isEmail(v.email)) found.email = t.emailNeeded;
            if (!cv.length) found.cv = t.cvNeeded;
            if (!privacy) found.privacy = t.privacyNeeded;
            if (f.fail(found)) return;
            p.onSubmit?.({ ...v, start, pool, files: [...cv, ...letterFile] });
            f.setDone(true);
          }}
        >
          <ErrorSummary ref={summaryRef} errors={summary} />
          <fieldset className="grid min-w-0 grid-cols-1 gap-5 sm:grid-cols-2">
            <legend className="mb-4 text-[15px] font-semibold text-foreground">{t.you}</legend>
            <Input id={`${id}-first`} label={t.firstName} required autoComplete="given-name" value={v.first} onChange={set('first')} error={f.errors.first} />
            <Input label={t.lastName} autoComplete="family-name" value={v.last} onChange={set('last')} />
            <Input id={`${id}-email`} type="email" label={t.email} required autoComplete="email" value={v.email} onChange={set('email')} error={f.errors.email} />
            <Input type="tel" inputMode="tel" label={t.phone} optional autoComplete="tel" value={v.phone} onChange={set('phone')} />
          </fieldset>
          <div className="border-t border-border pt-7"><fieldset className="grid min-w-0 gap-5">
            <legend className="mb-4 text-[15px] font-semibold text-foreground">{t.documents}</legend>
            <div id={`${id}-cv`}>
              <FileUpload label={<Req>{t.cv}</Req>} hint={t.cvHint} accept=".pdf" maxSize={10e6} maxFiles={1} multiple={false} items={asItems(cv, 'cv')} onFiles={(x) => (setCv(x.slice(0, 1)), f.clear('cv'))} onRemove={() => setCv([])} error={f.errors.cv} />
            </div>
            <div>
              <div className="flex flex-wrap items-center justify-between gap-3">
                <p className="text-sm font-medium text-foreground">
                  {t.letter} <span className="text-xs font-normal text-subtle-foreground">{t.optional}</span>
                </p>
                {/* Upload or write, a small switch with a sliding tile */}
                <div role="radiogroup" aria-label={t.letter} className="relative grid grid-cols-2 rounded-lg bg-[color-mix(in_oklab,var(--foreground)_6%,transparent)] p-0.5">
                  <span aria-hidden className={cn('absolute inset-y-0.5 start-0.5 w-[calc(50%-0.125rem)] rounded-md bg-card shadow-[var(--shadow-sm)] transition-[translate] duration-[420ms] ease-[cubic-bezier(0.3,1.25,0.5,1)] motion-reduce:transition-none', letterMode === 'upload' && 'translate-x-full rtl:-translate-x-full')} />
                  {(['write', 'upload'] as const).map((m) => (
                    <label key={m} className="relative z-10 flex min-h-11 cursor-pointer items-center justify-center rounded-md px-3 text-[13px] font-medium text-muted-foreground transition-colors has-[:checked]:text-foreground has-[:focus-visible]:shadow-[0_0_0_2px_color-mix(in_oklab,var(--primary)_45%,transparent)] sm:min-h-9">
                      <input type="radio" name={`${id}-lm`} checked={letterMode === m} onChange={() => setLetterMode(m)} className="sr-only" />
                      {m === 'write' ? t.letterWrite : t.letterUpload}
                    </label>
                  ))}
                </div>
              </div>
              <div key={letterMode} className="kit-rise mt-3">
                {letterMode === 'write' ? (
                  <Textarea aria-label={t.letter} placeholder={t.letterPlaceholder} value={v.letter} onChange={set('letter')} minRows={5} maxLength={3000} />
                ) : (
                  <FileUpload variant="compact" accept=".pdf,.doc,.docx" maxSize={10e6} maxFiles={1} multiple={false} items={asItems(letterFile, 'letter')} onFiles={(x) => setLetterFile(x.slice(0, 1))} onRemove={() => setLetterFile([])} />
                )}
              </div>
            </div>
          </fieldset></div>
          <div className="border-t border-border pt-7"><fieldset className="grid min-w-0 grid-cols-1 gap-5 sm:grid-cols-2">
            <legend className="mb-4 text-[15px] font-semibold text-foreground">{t.more}</legend>
            <DateInput label={t.start} optional today={p.today} min={p.today} value={start} onValueChange={setStart} />
            <Input label={t.salary} optional inputMode="numeric" value={v.salary} onChange={set('salary')} />
            <Input type="url" label={t.links} optional hint={t.linksHint} placeholder="https://" value={v.link} onChange={set('link')} className="sm:col-span-2" />
          </fieldset></div>
          <div className="grid gap-4 border-t border-border pt-7">
            <Privacy id={id} p={p} t={t} f={f} value={privacy} set={setPrivacy} />
            <Checkbox label={t.pool} checked={pool} onChange={(e) => setPool(e.target.checked)} />
          </div>
          <div className="flex justify-end">
            <Button type="submit" icon="send" magnetic className="max-sm:w-full">
              {p.submitLabel ?? t.send}
            </Button>
          </div>
        </form>
      </Reveal>
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* quick-apply                                                         */
/* ------------------------------------------------------------------ */

function QuickApply({ p, t }: { p: ApplicationFormProps; t: Texts }) {
  const id = useId();
  const f = useFormState();
  const [v, setV] = useState({ name: '', phone: '' });
  const [days, setDays] = useState<string[]>([]);
  const [shifts, setShifts] = useState<string[]>([]);
  const [cv, setCv] = useState<File[]>([]);
  const [privacy, setPrivacy] = useState(false);
  const formRef = useRef<HTMLFormElement>(null);
  const summaryRef = useRef<HTMLDivElement>(null);
  useFocusFirstError(formRef, f.attempt, summaryRef);
  const summary = summaryOf(f.errors, [
    ['name', `${id}-name`, t.name],
    ['phone', `${id}-phone`, t.phone],
    ['days', `${id}-days`, t.days],
    ['shifts', `${id}-shifts`, t.shifts],
    ['privacy', `${id}-privacy`, t.privacyLink],
  ]);
  if (f.done) return <Done p={p} t={t} onAgain={() => (setDays([]), setShifts([]), setPrivacy(false), f.setDone(false))} className="max-w-[40rem]" />;
  return (
    <Reveal effect="scale" className="mx-auto max-w-[40rem]">
      <form
        ref={formRef}
        noValidate
        className="kit-card overflow-hidden"
        onSubmit={(e) => {
          e.preventDefault();
          const found: Record<string, string> = {};
          if (!v.name.trim()) found.name = t.nameNeeded;
          if (!isPhone(v.phone)) found.phone = t.phoneNeeded;
          if (!days.length) found.days = t.daysNeeded;
          if (!shifts.length) found.shifts = t.shiftsNeeded;
          if (!privacy) found.privacy = t.privacyNeeded;
          if (f.fail(found)) return;
          p.onSubmit?.({ ...v, days, shifts, files: cv });
          f.setDone(true);
        }}
      >
        {p.role && (
          <div className="flex items-center gap-4 border-b border-border bg-surface px-6 py-4 sm:px-8">
            <span className="grid size-11 shrink-0 place-items-center rounded-xl bg-[color-mix(in_oklab,var(--primary)_14%,var(--card))] text-[color-mix(in_oklab,var(--primary)_85%,var(--foreground))]">
              <Icon name="briefcase" size={20} />
            </span>
            <span className="min-w-0">
              <span className="block truncate text-[16px] font-semibold text-foreground">{p.role.title}</span>
              <span className="block text-[13px] leading-snug text-muted-foreground">{[p.role.location, p.role.type, p.role.salary].filter(Boolean).join(' · ')}</span>
            </span>
          </div>
        )}
        <div className="grid gap-6 p-6 sm:p-8">
          <ErrorSummary ref={summaryRef} errors={summary} />
          <div className="grid grid-cols-1 gap-5 sm:grid-cols-2">
            <Input id={`${id}-name`} label={t.name} required autoComplete="name" size="lg" value={v.name} onChange={(e) => (setV((x) => ({ ...x, name: e.target.value })), f.clear('name'))} error={f.errors.name} />
            <Input id={`${id}-phone`} type="tel" inputMode="tel" label={t.phone} required autoComplete="tel" size="lg" value={v.phone} onChange={(e) => (setV((x) => ({ ...x, phone: e.target.value })), f.clear('phone'))} error={f.errors.phone} />
          </div>
          <ChipGroup id={`${id}-days`} legend={t.days} required multiple options={(p.days ?? []).map((d) => ({ value: d, label: d }))} value={days} onChange={(x) => (setDays(x), f.clear('days'))} error={f.errors.days} layout={(p.days?.length ?? 0) === 7 ? 7 : 'wrap'} />
          <ChipGroup id={`${id}-shifts`} legend={t.shifts} required multiple options={(p.shifts ?? []).map((s) => ({ value: s, label: s, icon: 'clock' as IconName }))} value={shifts} onChange={(x) => (setShifts(x), f.clear('shifts'))} error={f.errors.shifts} layout={(p.shifts?.length ?? 0) === 3 ? 3 : 'wrap'} />
          <FileUpload variant="compact" label={t.cvOptional} hint={t.cvHint} accept=".pdf,image/*" maxSize={10e6} maxFiles={1} multiple={false} items={asItems(cv, 'cv')} onFiles={(x) => setCv(x.slice(0, 1))} onRemove={() => setCv([])} />
          <Privacy id={id} p={p} t={t} f={f} value={privacy} set={setPrivacy} />
          <Button type="submit" size="lg" icon="send" className="w-full">
            {p.submitLabel ?? t.send}
          </Button>
          <p className="-mt-2 text-center text-[13px] text-muted-foreground">{t.quickNote}</p>
        </div>
      </form>
    </Reveal>
  );
}

/* ------------------------------------------------------------------ */
/* guided-letter                                                       */
/* ------------------------------------------------------------------ */

const countWords = (s: string) => (s.trim() ? s.trim().split(/\s+/).length : 0);

function GuidedLetter({ p, t }: { p: ApplicationFormProps; t: Texts }) {
  const id = useId();
  const locale = useLocale();
  const f = useFormState();
  const prompts = p.prompts ?? [];
  const [answers, setAnswers] = useState<Record<string, string>>({});
  const [who, setWho] = useState({ name: '', email: '' });
  const [cv, setCv] = useState<File[]>([]);
  const [privacy, setPrivacy] = useState(false);
  const formRef = useRef<HTMLFormElement>(null);
  const summaryRef = useRef<HTMLDivElement>(null);
  useFocusFirstError(formRef, f.attempt, summaryRef);
  const parts = prompts.map((q) => answers[q.id]?.trim()).filter(Boolean) as string[];
  const summary = summaryOf(f.errors, [
    ...prompts.map((q) => [q.id, `${id}-${q.id}`, q.title] as [string, string, string]),
    ['name', `${id}-name`, t.name],
    ['email', `${id}-email`, t.email],
    ['cv', `${id}-cv`, t.cv],
    ['privacy', `${id}-privacy`, t.privacyLink],
  ]);
  if (f.done) return <Done p={p} t={t} onAgain={() => (setAnswers({}), setPrivacy(false), f.setDone(false))} className="max-w-[48rem]" />;
  return (
    <form
      ref={formRef}
      noValidate
      className="grid grid-cols-1 gap-8 lg:grid-cols-[minmax(0,1fr)_minmax(0,0.9fr)] lg:gap-10"
      onSubmit={(e) => {
        e.preventDefault();
        const found: Record<string, string> = {};
        for (const q of prompts) {
          const n = countWords(answers[q.id] ?? '');
          if (!n) found[q.id] = t.promptNeeded;
          else if (q.words && n > q.words) found[q.id] = t.tooLong.replace('{n}', String(n - q.words));
        }
        if (!who.name.trim()) found.name = t.nameNeeded;
        if (!isEmail(who.email)) found.email = t.emailNeeded;
        if (!cv.length) found.cv = t.cvNeeded;
        if (!privacy) found.privacy = t.privacyNeeded;
        if (f.fail(found)) return;
        p.onSubmit?.({ answers, ...who, files: cv });
        f.setDone(true);
      }}
    >
      <div className="grid min-w-0 gap-5">
        <ErrorSummary ref={summaryRef} errors={summary} />
        <Stagger step={100} as="ol" className="grid gap-4">
          {prompts.map((q, i) => {
            const n = countWords(answers[q.id] ?? '');
            const over = q.words !== undefined && n > q.words;
            return (
              <li key={q.id} className="kit-card p-5 sm:p-6">
                <div className="flex items-baseline gap-3">
                  <span aria-hidden className="text-[13px] font-semibold tabular-nums text-[color-mix(in_oklab,var(--primary)_80%,var(--foreground))]">
                    {i + 1}
                  </span>
                  <div className="min-w-0 flex-1">
                    <Textarea
                      id={`${id}-${q.id}`}
                      label={q.title}
                      required
                      hint={f.errors[q.id] ? undefined : q.hint}
                      error={f.errors[q.id]}
                      value={answers[q.id] ?? ''}
                      onChange={(e) => (setAnswers((a) => ({ ...a, [q.id]: e.target.value })), f.clear(q.id))}
                      minRows={3}
                      invalid={over}
                      footer={
                        q.words ? (
                          <span className={cn('text-xs tabular-nums transition-colors', over ? 'font-medium text-destructive' : n > q.words * 0.85 ? 'text-foreground' : 'text-subtle-foreground')}>
                            {t.words.replace('{n}', n.toLocaleString(locale === 'de' ? 'de-DE' : 'en-US')).replace('{max}', String(q.words))}
                          </span>
                        ) : undefined
                      }
                    />
                  </div>
                </div>
              </li>
            );
          })}
        </Stagger>
        <div className="kit-card grid grid-cols-1 gap-5 p-5 sm:grid-cols-2 sm:p-6">
          <Input id={`${id}-name`} label={t.name} required autoComplete="name" value={who.name} onChange={(e) => (setWho((w) => ({ ...w, name: e.target.value })), f.clear('name'))} error={f.errors.name} />
          <Input id={`${id}-email`} type="email" label={t.email} required autoComplete="email" value={who.email} onChange={(e) => (setWho((w) => ({ ...w, email: e.target.value })), f.clear('email'))} error={f.errors.email} />
          <div id={`${id}-cv`} className="sm:col-span-2">
            <FileUpload variant="compact" label={<Req>{t.cv}</Req>} hint={t.cvHint} accept=".pdf" maxSize={10e6} maxFiles={1} multiple={false} items={asItems(cv, 'cv')} onFiles={(x) => (setCv(x.slice(0, 1)), f.clear('cv'))} onRemove={() => setCv([])} error={f.errors.cv} />
          </div>
          <div className="sm:col-span-2">
            <Privacy id={id} p={p} t={t} f={f} value={privacy} set={setPrivacy} />
          </div>
        </div>
      </div>
      {/* The letter builds itself from the answers, paper-like and calm */}
      <div className="min-w-0 lg:sticky lg:top-24 lg:self-start">
        <Reveal effect="rise" delay={120}>
          <div className="rounded-2xl border border-border bg-card p-6 shadow-[var(--highlight),var(--shadow-md)] sm:p-8">
            <p className="flex items-center gap-2 text-[13px] font-medium text-muted-foreground">
              <Icon name="file" size={15} />
              {t.preview}
            </p>
            <div className="mt-5 min-h-[9rem] text-pretty lg:min-h-[14rem] text-[14.5px] leading-[1.7] text-foreground">
              {parts.length ? (
                <>
                  <p>{t.greeting}</p>
                  {parts.map((x, i) => (
                    <p key={i} className="kit-rise mt-3 whitespace-pre-line">
                      {x}
                    </p>
                  ))}
                  <p className="mt-5">{t.closing}</p>
                  <p className="font-medium">{who.name || '…'}</p>
                </>
              ) : (
                <div className="grid gap-2.5">
                  <p className="text-muted-foreground">{t.previewEmpty}</p>
                  {[92, 100, 84, 96, 60].map((w, i) => (
                    <span key={i} aria-hidden className="h-2.5 rounded-full bg-[color-mix(in_oklab,var(--foreground)_7%,transparent)]" style={{ width: `${w}%` }} />
                  ))}
                </div>
              )}
            </div>
            <Button type="submit" icon="send" className="mt-7 w-full">
              {p.submitLabel ?? t.send}
            </Button>
          </div>
        </Reveal>
      </div>
    </form>
  );
}

/* ------------------------------------------------------------------ */
/* eligibility                                                         */
/* ------------------------------------------------------------------ */

function Eligibility({ p, t }: { p: ApplicationFormProps; t: Texts }) {
  const id = useId();
  const f = useFormState();
  const checks = p.checks ?? [];
  const [answers, setAnswers] = useState<Record<string, 'yes' | 'no'>>({});
  const [v, setV] = useState({ name: '', email: '', motivation: '' });
  const [files, setFiles] = useState<File[]>([]);
  const [privacy, setPrivacy] = useState(false);
  const formRef = useRef<HTMLFormElement>(null);
  const summaryRef = useRef<HTMLDivElement>(null);
  useFocusFirstError(formRef, f.attempt, summaryRef);
  const allAnswered = checks.every((c) => answers[c.id]);
  const misses = checks.filter((c) => answers[c.id] && answers[c.id] !== (c.fits ?? 'yes'));
  const fits = allAnswered && misses.length === 0;
  const summary = summaryOf(f.errors, [
    ['name', `${id}-name`, t.name],
    ['email', `${id}-email`, t.email],
    ['motivation', `${id}-motivation`, t.motivation],
    ['privacy', `${id}-privacy`, t.privacyLink],
  ]);
  if (f.done) return <Done p={p} t={t} onAgain={() => (setAnswers({}), setPrivacy(false), f.setDone(false))} className="max-w-[46rem]" />;
  return (
    <div className="mx-auto max-w-[46rem]">
      <Reveal effect="rise" className="kit-card p-6 sm:p-8">
        <p className="text-[17px] font-semibold text-foreground">{t.check}</p>
        <p className="mt-1 text-[14px] text-muted-foreground">{t.checkText}</p>
        <Stagger step={90} as="ol" className="mt-6 grid gap-0 border-t border-border">
          {checks.map((c, i) => {
            const a = answers[c.id];
            const miss = a && a !== (c.fits ?? 'yes');
            return (
              <li key={c.id} className="border-b border-border py-4">
                <fieldset className="flex min-w-0 flex-col gap-3 sm:flex-row sm:items-center sm:justify-between">
                  <legend className="sr-only">{c.title}</legend>
                  <div aria-hidden className="min-w-0">
                    <p className="text-[15px] font-medium leading-snug text-foreground">
                      <span className="me-2 tabular-nums text-subtle-foreground">{i + 1}</span>
                      {c.title}
                    </p>
                    {c.hint && <p className="mt-0.5 text-[13px] text-muted-foreground">{c.hint}</p>}
                  </div>
                  <div className="flex shrink-0 gap-2">
                    {(['yes', 'no'] as const).map((x) => (
                      <label key={x} className={cn('flex min-h-11 min-w-[5.5rem] flex-1 cursor-pointer items-center justify-center gap-1.5 rounded-lg border px-4 text-[14px] font-medium transition-[background-color,border-color,color] duration-200 has-[:focus-visible]:shadow-[0_0_0_3px_color-mix(in_oklab,var(--primary)_28%,transparent)] sm:flex-none', a === x ? 'border-primary bg-[color-mix(in_oklab,var(--primary)_12%,var(--card))] text-foreground' : 'border-border bg-card text-foreground hover:border-border-strong')}>
                        <input type="radio" name={`${id}-${c.id}`} checked={a === x} onChange={() => setAnswers((s) => ({ ...s, [c.id]: x }))} className="sr-only" />
                        {a === x && <Icon name="check" size={15} strokeWidth={2.2} className="text-[color-mix(in_oklab,var(--primary)_85%,var(--foreground))]" />}
                        {x === 'yes' ? t.yes : t.no}
                      </label>
                    ))}
                  </div>
                </fieldset>
                {miss && c.explain && <p className="kit-rise mt-3 rounded-lg bg-[color-mix(in_oklab,var(--warning)_16%,var(--card))] px-3.5 py-2.5 text-[13.5px] leading-snug text-warning-foreground">{c.explain}</p>}
              </li>
            );
          })}
        </Stagger>
        {allAnswered && (
          <p role="status" className={cn('kit-rise mt-5 flex items-start gap-3 rounded-xl border p-4', fits ? 'border-[color-mix(in_oklab,var(--success)_35%,var(--border))] bg-[color-mix(in_oklab,var(--success)_8%,var(--card))]' : 'border-border bg-surface')}>
            <Icon name={fits ? 'check-circle' : 'info'} size={20} className={cn('mt-0.5 shrink-0', fits ? 'text-success' : 'text-muted-foreground')} />
            <span>
              <span className="block text-[15px] font-semibold text-foreground">{fits ? t.fitsTitle : t.notYetTitle}</span>
              <span className="mt-0.5 block text-[13.5px] text-muted-foreground">{fits ? t.fitsText : t.notYetText}</span>
            </span>
          </p>
        )}
      </Reveal>
      {/* The application opens with a soft height once every answer fits */}
      <Unfold open={fits}>
        <form
          ref={formRef}
          noValidate
          className="kit-card mt-5 grid gap-6 p-6 sm:p-8"
          onSubmit={(e) => {
            e.preventDefault();
            const found: Record<string, string> = {};
            if (!v.name.trim()) found.name = t.nameNeeded;
            if (!isEmail(v.email)) found.email = t.emailNeeded;
            if (!v.motivation.trim()) found.motivation = t.motivationNeeded;
            if (!privacy) found.privacy = t.privacyNeeded;
            if (f.fail(found)) return;
            p.onSubmit?.({ answers, ...v, files });
            f.setDone(true);
          }}
        >
          <ErrorSummary ref={summaryRef} errors={summary} />
          <div className="grid grid-cols-1 gap-5 sm:grid-cols-2">
            <Input id={`${id}-name`} label={t.name} required autoComplete="name" value={v.name} onChange={(e) => (setV((x) => ({ ...x, name: e.target.value })), f.clear('name'))} error={f.errors.name} />
            <Input id={`${id}-email`} type="email" label={t.email} required autoComplete="email" value={v.email} onChange={(e) => (setV((x) => ({ ...x, email: e.target.value })), f.clear('email'))} error={f.errors.email} />
          </div>
          <Textarea id={`${id}-motivation`} label={t.motivation} required value={v.motivation} onChange={(e) => (setV((x) => ({ ...x, motivation: e.target.value })), f.clear('motivation'))} error={f.errors.motivation} minRows={5} maxLength={2000} />
          <FileUpload label={t.documents} hint={t.cvHint} accept=".pdf" maxSize={10e6} maxFiles={3} items={asItems(files, 'doc')} onFiles={(x) => setFiles((y) => [...y, ...x].slice(0, 3))} onRemove={(fid) => setFiles((y) => y.filter((_, i) => `doc-${i}-${y[i].name}` !== fid))} />
          <Privacy id={id} p={p} t={t} f={f} value={privacy} set={setPrivacy} />
          <div className="flex justify-end">
            <Button type="submit" icon="send" className="max-sm:w-full">
              {p.submitLabel ?? t.send}
            </Button>
          </div>
        </form>
      </Unfold>
    </div>
  );
}

/* ------------------------------------------------------------------ */
/* Section                                                             */
/* ------------------------------------------------------------------ */

/**
 * Applications for roles, shifts and programmes.
 *   <ApplicationForm variant="job" role={{ title, location, type, points }} retention="six months" privacyHref="/privacy" />
 */
export function ApplicationForm(props: ApplicationFormProps) {
  const { variant = 'job', eyebrow, title, description, labels, className } = props;
  const t = useTexts(TEXTS, labels);
  const center = variant !== 'job';
  return (
    <Section className={className}>
      <FlowHead eyebrow={eyebrow} title={title} description={description} align={center ? 'center' : 'left'} className="mb-10 sm:mb-14" />
      {variant === 'job' && <Job p={props} t={t} />}
      {variant === 'quick-apply' && <QuickApply p={props} t={t} />}
      {variant === 'guided-letter' && <GuidedLetter p={props} t={t} />}
      {variant === 'eligibility' && <Eligibility p={props} t={t} />}
    </Section>
  );
}