01電話番号の自動ハイフン

<main class="stage">
  <div class="field is-demo" id="field">
    <label class="field__label" for="phone-input">電話番号</label>
    <input class="field__input" id="phone-input" type="tel" inputmode="numeric" autocomplete="tel-national" placeholder="010-0000-0000" aria-describedby="phone-hint" maxlength="13">
    <p class="field__hint" id="phone-hint">数字だけ入力してもハイフンが自動的に入ります</p>
  </div>
</main>

@use "../../../../site/static/demo-tokens" as *;

// ── 변수 3개 ──────────────────────────────────────────
$duration: $dur-quick;      // 포커스 링 전환 시간
$easing: $ease-out;         // 포커스 링 전환 이징
$color: $subject-blue;      // 포커스 링 색

// ── 데모 무대 ──────────────────────────────────────────
@include stage($stage-ink);

.field {
  box-sizing: border-box;
  width: min(260px, 84vw);
  background: $subject-cream;
  border-radius: $r-card;
  padding: $sp-5 $sp-5 $sp-4;
  box-shadow: $shadow-raised;

  &__label {
    display: block;
    margin: 0 0 $sp-2;
    font-weight: 700;
    font-size: 13px;
    line-height: 1;
    font-family: inherit;
    color: $stage-ink;
  }

  &__input {
    box-sizing: border-box;
    width: 100%;
    border: 2px solid transparent;
    border-radius: $r-control;
    padding: $sp-3 $sp-4;
    font-weight: 600;
    font-size: clamp(15px, 4.4vw, 18px);
    letter-spacing: .02em;
    font-family: inherit;
    color: $stage-ink;
    background: #fff;
    transition: border-color $duration $easing, box-shadow $duration $easing;

    &:focus {
      outline: none;
      border-color: $color;
      box-shadow: 0 0 0 3px rgba(47, 109, 246, .18);
    }
  }

  &__hint {
    margin: $sp-2 0 0;
    font-size: 12px;
    line-height: 1.4;
    font-family: inherit;
    color: rgba(23, 20, 26, .6);
  }
}

// ── 접근성: 모션 축소 시 포커스 링 전환을 즉시 처리 ────────────
@media (prefers-reduced-motion: reduce) {
  .field__input { transition: none; }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.field {
  box-sizing: border-box;
  width: min(260px, 84vw);
  background: #fff7e6;
  border-radius: 16px;
  padding: 20px 20px 16px;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
}
.field__label {
  display: block;
  margin: 0 0 8px;
  font-weight: 700;
  font-size: 13px;
  line-height: 1;
  font-family: inherit;
  color: #17141a;
}
.field__input {
  box-sizing: border-box;
  width: 100%;
  border: 2px solid transparent;
  border-radius: 12px;
  padding: 12px 16px;
  font-weight: 600;
  font-size: clamp(15px, 4.4vw, 18px);
  letter-spacing: 0.02em;
  font-family: inherit;
  color: #17141a;
  background: #fff;
  transition: border-color 220ms ease-out, box-shadow 220ms ease-out;
}
.field__input:focus {
  outline: none;
  border-color: #2f6df6;
  box-shadow: 0 0 0 3px rgba(47, 109, 246, 0.18);
}
.field__hint {
  margin: 8px 0 0;
  font-size: 12px;
  line-height: 1.4;
  font-family: inherit;
  color: rgba(23, 20, 26, 0.6);
}

@media (prefers-reduced-motion: reduce) {
  .field__input {
    transition: none;
  }
}

(function () {
  var field = document.getElementById('field');
  var input = document.getElementById('phone-input');

  function format(digits) {
    digits = digits.replace(/\D/g, '').slice(0, 11);
    if (digits.length < 4) return digits;
    if (digits.length < 8) return digits.slice(0, 3) + '-' + digits.slice(3);
    return digits.slice(0, 3) + '-' + digits.slice(3, 7) + '-' + digits.slice(7);
  }

  input.addEventListener('input', function () {
    input.value = format(input.value);
  });

  function stopDemo() {
    if (!field.classList.contains('is-demo')) return;
    field.classList.remove('is-demo');
    clearInterval(timer);
    input.value = '';
  }
  input.addEventListener('pointerdown', stopDemo);
  input.addEventListener('keydown', stopDemo);

  var digits = '01012345678';
  var i = 0;
  var timer = setInterval(function () {
    if (i > digits.length) { i = 0; input.value = ''; return; }
    input.value = format(digits.slice(0, i));
    i++;
  }, 160);
})();

import { useRef, useState } from "react";
import styles from "./PhoneFormat.module.scss";

export type PhoneFormatProps = {
  label?: string;
  hint?: string;
  color?: string;
};

function format(raw: string): string {
  const d = raw.replace(/\D/g, "").slice(0, 11);
  if (d.length < 4) return d;
  if (d.length < 8) return `${d.slice(0, 3)}-${d.slice(3)}`;
  return `${d.slice(0, 3)}-${d.slice(3, 7)}-${d.slice(7)}`;
}

export default function PhoneFormat({
  label = "전화번호",
  hint = "숫자만 입력해도 하이픈이 자동으로 들어갑니다",
  color = "#2f6df6",
}: PhoneFormatProps) {
  const [value, setValue] = useState("");
  const id = useRef("phone-input-" + Math.random().toString(36).slice(2)).current;

  return (
    <div className={styles.field} style={{ ["--color" as string]: color }}>
      <label className={styles.label} htmlFor={id}>{label}</label>
      <input
        className={styles.input}
        id={id}
        type="tel"
        inputMode="numeric"
        autoComplete="tel-national"
        placeholder="010-0000-0000"
        maxLength={13}
        value={value}
        aria-describedby={id + "-hint"}
        onChange={(e: any) => setValue(format(e.target.value))}
      />
      <p className={styles.hint} id={id + "-hint"}>{hint}</p>
    </div>
  );
}