Telescope

import { useState } from 'react';

const css = `
  .slider-telescope { display: grid; gap: 12px; width: 240px; }
  .slider-telescope__row { display: flex; align-items: center; gap: 14px; }
  .slider-telescope__scope { position: relative; width: 122px; height: 100px; }
  .slider-telescope__arm { position: absolute; left: 6px; top: 38px; width: 120px; height: 22px; transform: rotate(-18deg); transform-origin: 20px 50%; }
  .slider-telescope__tube { position: absolute; top: 50%; border-radius: 3px; box-shadow: inset 0 1px 0 light-dark(#5f626a, #a7abb2); transition: transform 0.45s cubic-bezier(0.3, 1.3, 0.5, 1); }
  .slider-telescope__tube--3 { left: 46px; width: 40px; height: 10px; margin-top: -5px; background: light-dark(#6d7179, #7d8087); transform: translateX(calc(var(--slider-telescope-v) * 34px)); }
  .slider-telescope__tube--2 { left: 30px; width: 44px; height: 14px; margin-top: -7px; background: light-dark(#5f626a, #a7abb2); transform: translateX(calc(var(--slider-telescope-v) * 18px)); }
  .slider-telescope__tube--1 { left: 8px; width: 46px; height: 20px; margin-top: -10px; background: light-dark(#50535b, #c6c8cd); }
  .slider-telescope__eye { position: absolute; left: 0; top: 50%; width: 10px; height: 8px; margin-top: -4px; border-radius: 2px; background: light-dark(#cbced3, #393c41); }
  .slider-telescope__leg { position: absolute; top: 52px; left: 26px; width: 3px; height: 46px; border-radius: 2px; background: light-dark(#cbced3, #393c41); transform-origin: 50% 0; }
  .slider-telescope__view { position: relative; flex: none; width: 104px; height: 104px; overflow: hidden; border-radius: 50%; background: light-dark(#fbfcfd, #121417); box-shadow: inset 0 0 0 3px light-dark(#dbdde1, #2e3035), inset 0 0 18px 6px light-dark(rgba(0, 0, 0, 0.18), rgba(0, 0, 0, 0.6)); }
  .slider-telescope__moon {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 34px;
    height: 34px;
    margin: -17px;
    border-radius: 50%;
    background:
      radial-gradient(circle at 30% 35%, light-dark(#5f626a, #a7abb2) 0 3px, transparent 3.5px),
      radial-gradient(circle at 62% 60%, light-dark(#5f626a, #a7abb2) 0 4.5px, transparent 5px),
      radial-gradient(circle at 70% 28%, light-dark(#5f626a, #a7abb2) 0 2px, transparent 2.5px),
      radial-gradient(circle at 38% 72%, light-dark(#5f626a, #a7abb2) 0 2.5px, transparent 3px),
      radial-gradient(circle at 35% 30%, light-dark(#373a40, #f1f2f3), light-dark(#50535b, #c6c8cd));
    box-shadow: 0 0 14px color-mix(in oklab, light-dark(#373a40, #f1f2f3) 35%, transparent);
    transform: scale(calc(1 + var(--slider-telescope-v) * 2.6));
    transition: transform 0.45s cubic-bezier(0.3, 1.3, 0.5, 1);
  }
  .slider-telescope__cross { position: absolute; inset: 0; background: linear-gradient(light-dark(#6d7179, #7d8087), light-dark(#6d7179, #7d8087)) 50% 50% / 1px 100% no-repeat, linear-gradient(light-dark(#6d7179, #7d8087), light-dark(#6d7179, #7d8087)) 50% 50% / 100% 1px no-repeat; opacity: 0.45; }
  .slider-telescope__mag { position: absolute; right: 50%; bottom: 10px; transform: translateX(50%); color: light-dark(#42454c, #e5e6e9); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 9px; }
  .slider-telescope__track { position: relative; height: 24px; }
  .slider-telescope__rail { position: absolute; left: 0; right: 0; top: 10px; height: 4px; border-radius: 2px; background: light-dark(#ebedf0, #232529); }
  .slider-telescope__fill { position: absolute; left: 0; top: 10px; height: 4px; border-radius: 2px; width: calc(9px + var(--slider-telescope-v) * (100% - 18px)); background: light-dark(#50535b, #c6c8cd); }
  .slider-telescope__thumb { position: absolute; top: 3px; left: calc(var(--slider-telescope-v) * (100% - 18px)); width: 18px; height: 18px; border-radius: 50%; background: light-dark(#373a40, #f1f2f3); box-shadow: inset 0 0 0 4px light-dark(#50535b, #c6c8cd), 0 2px 6px light-dark(rgba(0, 0, 0, 0.12), rgba(0, 0, 0, 0.4)); }
  .slider-telescope:has(.slider-telescope__input:focus-visible) .slider-telescope__thumb { outline: 2px solid light-dark(#50535b, #c6c8cd); outline-offset: 3px; }
  .slider-telescope__input { position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: pointer; -webkit-appearance: none; appearance: none; background: none; }
  .slider-telescope__input::-webkit-slider-thumb { -webkit-appearance: none; width: 18px; height: 18px; }
  .slider-telescope__input::-moz-range-thumb { width: 18px; height: 18px; border: 0; }
  @media (prefers-reduced-motion: reduce) {
    .slider-telescope * { transition-duration: 0.01s !important; }
  }
`;

export function TelescopeSlider() {
  const [v, setV] = useState(30);
  const mag = Math.round(10 + (v / 100) * 140);
  return (
    <>
      <style>
        {css}
      </style>
      <div className="slider-telescope" style={{ '--slider-telescope-v': v / 100 } as React.CSSProperties}>
        <div className="slider-telescope__row" aria-hidden="true">
          <span className="slider-telescope__scope">
            <span className="slider-telescope__leg" style={{ transform: 'rotate(22deg)' }} />
            <span className="slider-telescope__leg" style={{ transform: 'rotate(-14deg)' }} />
            <span className="slider-telescope__leg" style={{ transform: 'rotate(4deg)' }} />
            <span className="slider-telescope__arm">
              <span className="slider-telescope__tube slider-telescope__tube--3" />
              <span className="slider-telescope__tube slider-telescope__tube--2" />
              <span className="slider-telescope__tube slider-telescope__tube--1" />
              <span className="slider-telescope__eye" />
            </span>
          </span>
          <span className="slider-telescope__view">
            <span className="slider-telescope__moon" />
            <span className="slider-telescope__cross" />
            <span className="slider-telescope__mag">{mag}×</span>
          </span>
        </div>
        <div className="slider-telescope__track">
          <span className="slider-telescope__rail" />
          <span className="slider-telescope__fill" />
          <span className="slider-telescope__thumb" />
          <input className="slider-telescope__input" type="range" min={0} max={100} value={v} onChange={(e) => setV(+e.target.value)} aria-label="Zoom" aria-valuetext={`${mag} times`} />
        </div>
      </div>
    </>
  );
}