// Tweaks panel — floating settings drawer with persisted form controls.
// Adapted from the Claude design bundle's tweaks-panel.jsx; the host-iframe
// protocol is replaced with localStorage persistence, and open/close is
// driven by an explicit prop instead of postMessage.

const __TWEAKS_STYLE = `
  .twk-panel{position:fixed;right:16px;bottom:16px;z-index:2147483646;width:280px;
    max-height:calc(100vh - 32px);display:flex;flex-direction:column;
    background:rgba(250,249,247,.92);color:#29261b;
    -webkit-backdrop-filter:blur(24px) saturate(160%);backdrop-filter:blur(24px) saturate(160%);
    border:.5px solid rgba(255,255,255,.6);border-radius:14px;
    box-shadow:0 1px 0 rgba(255,255,255,.5) inset,0 12px 40px rgba(0,0,0,.18);
    font:11.5px/1.4 ui-sans-serif,system-ui,-apple-system,sans-serif;overflow:hidden}
  .twk-hd{display:flex;align-items:center;justify-content:space-between;
    padding:10px 8px 10px 14px;cursor:move;user-select:none}
  .twk-hd b{font-size:12px;font-weight:600;letter-spacing:.01em}
  .twk-x{appearance:none;border:0;background:transparent;color:rgba(41,38,27,.55);
    width:22px;height:22px;border-radius:6px;cursor:pointer;font-size:13px;line-height:1}
  .twk-x:hover{background:rgba(0,0,0,.06);color:#29261b}
  .twk-body{padding:2px 14px 14px;display:flex;flex-direction:column;gap:10px;
    overflow-y:auto;overflow-x:hidden;min-height:0;
    scrollbar-width:thin;scrollbar-color:rgba(0,0,0,.15) transparent}
  .twk-body::-webkit-scrollbar{width:8px}
  .twk-body::-webkit-scrollbar-track{background:transparent;margin:2px}
  .twk-body::-webkit-scrollbar-thumb{background:rgba(0,0,0,.15);border-radius:4px;
    border:2px solid transparent;background-clip:content-box}
  .twk-body::-webkit-scrollbar-thumb:hover{background:rgba(0,0,0,.25);
    border:2px solid transparent;background-clip:content-box}
  .twk-row{display:flex;flex-direction:column;gap:5px}
  .twk-row-h{flex-direction:row;align-items:center;justify-content:space-between;gap:10px}
  .twk-lbl{display:flex;justify-content:space-between;align-items:baseline;
    color:rgba(41,38,27,.72)}
  .twk-lbl>span:first-child{font-weight:500}
  .twk-val{color:rgba(41,38,27,.5);font-variant-numeric:tabular-nums}

  .twk-sect{font-size:10px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;
    color:rgba(41,38,27,.45);padding:10px 0 0}
  .twk-sect:first-child{padding-top:0}

  .twk-field{appearance:none;width:100%;height:26px;padding:0 8px;
    border:.5px solid rgba(0,0,0,.1);border-radius:7px;
    background:rgba(255,255,255,.6);color:inherit;font:inherit;outline:none}
  .twk-field:focus{border-color:rgba(0,0,0,.25);background:rgba(255,255,255,.85)}
  select.twk-field{padding-right:22px;
    background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6'><path fill='rgba(0,0,0,.5)' d='M0 0h10L5 6z'/></svg>");
    background-repeat:no-repeat;background-position:right 8px center}

  .twk-slider{appearance:none;-webkit-appearance:none;width:100%;height:4px;margin:6px 0;
    border-radius:999px;background:rgba(0,0,0,.12);outline:none}
  .twk-slider::-webkit-slider-thumb{-webkit-appearance:none;appearance:none;
    width:14px;height:14px;border-radius:50%;background:#fff;
    border:.5px solid rgba(0,0,0,.12);box-shadow:0 1px 3px rgba(0,0,0,.2);cursor:pointer}
  .twk-slider::-moz-range-thumb{width:14px;height:14px;border-radius:50%;
    background:#fff;border:.5px solid rgba(0,0,0,.12);box-shadow:0 1px 3px rgba(0,0,0,.2);cursor:pointer}

  .twk-seg{position:relative;display:flex;padding:2px;border-radius:8px;
    background:rgba(0,0,0,.06);user-select:none}
  .twk-seg-thumb{position:absolute;top:2px;bottom:2px;border-radius:6px;
    background:rgba(255,255,255,.9);box-shadow:0 1px 2px rgba(0,0,0,.12);
    transition:left .15s cubic-bezier(.3,.7,.4,1),width .15s}
  .twk-seg.dragging .twk-seg-thumb{transition:none}
  .twk-seg button{appearance:none;position:relative;z-index:1;flex:1;border:0;
    background:transparent;color:inherit;font:inherit;font-weight:500;min-height:22px;
    border-radius:6px;cursor:pointer;padding:4px 6px;line-height:1.2;
    overflow-wrap:anywhere}

  .twk-toggle{position:relative;width:32px;height:18px;border:0;border-radius:999px;
    background:rgba(0,0,0,.15);transition:background .15s;cursor:pointer;padding:0}
  .twk-toggle[data-on="1"]{background:#34c759}
  .twk-toggle i{position:absolute;top:2px;left:2px;width:14px;height:14px;border-radius:50%;
    background:#fff;box-shadow:0 1px 2px rgba(0,0,0,.25);transition:transform .15s}
  .twk-toggle[data-on="1"] i{transform:translateX(14px)}

  .twk-chips{display:flex;gap:6px}
  .twk-chip{position:relative;appearance:none;flex:1;min-width:0;height:46px;
    padding:0;border:0;border-radius:6px;overflow:hidden;cursor:pointer;
    box-shadow:0 0 0 .5px rgba(0,0,0,.12),0 1px 2px rgba(0,0,0,.06);
    transition:transform .12s cubic-bezier(.3,.7,.4,1),box-shadow .12s}
  .twk-chip:hover{transform:translateY(-1px);
    box-shadow:0 0 0 .5px rgba(0,0,0,.18),0 4px 10px rgba(0,0,0,.12)}
  .twk-chip[data-on="1"]{box-shadow:0 0 0 1.5px rgba(0,0,0,.85),
    0 2px 6px rgba(0,0,0,.15)}
  .twk-chip svg{position:absolute;top:6px;left:6px;width:13px;height:13px;
    filter:drop-shadow(0 1px 1px rgba(0,0,0,.3))}
`;

// localStorage-backed tweak state. Defaults seed initial values; any persisted
// keys override them so existing tweaks survive a reload.
function useTweaks(defaults, storageKey = 'russianslovo.tweaks') {
  const [values, setValues] = React.useState(() => {
    try {
      const stored = localStorage.getItem(storageKey);
      if (stored) return { ...defaults, ...JSON.parse(stored) };
    } catch (e) { /* localStorage unavailable */ }
    return defaults;
  });
  const setTweak = React.useCallback((keyOrEdits, val) => {
    const edits = typeof keyOrEdits === 'object' && keyOrEdits !== null
      ? keyOrEdits : { [keyOrEdits]: val };
    setValues((prev) => {
      const next = { ...prev, ...edits };
      try { localStorage.setItem(storageKey, JSON.stringify(next)); } catch (e) { /* ignore */ }
      return next;
    });
  }, [storageKey]);
  return [values, setTweak];
}

function TweaksPanel({ open, onClose, title = 'Tweaks', children }) {
  const dragRef = React.useRef(null);
  const offsetRef = React.useRef({ x: 16, y: 16 });
  const PAD = 16;

  const clampToViewport = React.useCallback(() => {
    const panel = dragRef.current;
    if (!panel) return;
    const w = panel.offsetWidth, h = panel.offsetHeight;
    const maxRight = Math.max(PAD, window.innerWidth - w - PAD);
    const maxBottom = Math.max(PAD, window.innerHeight - h - PAD);
    offsetRef.current = {
      x: Math.min(maxRight, Math.max(PAD, offsetRef.current.x)),
      y: Math.min(maxBottom, Math.max(PAD, offsetRef.current.y)),
    };
    panel.style.right = offsetRef.current.x + 'px';
    panel.style.bottom = offsetRef.current.y + 'px';
  }, []);

  React.useEffect(() => {
    if (!open) return;
    clampToViewport();
    if (typeof ResizeObserver === 'undefined') {
      window.addEventListener('resize', clampToViewport);
      return () => window.removeEventListener('resize', clampToViewport);
    }
    const ro = new ResizeObserver(clampToViewport);
    ro.observe(document.documentElement);
    return () => ro.disconnect();
  }, [open, clampToViewport]);

  const onDragStart = (e) => {
    const panel = dragRef.current;
    if (!panel) return;
    const r = panel.getBoundingClientRect();
    const sx = e.clientX, sy = e.clientY;
    const startRight = window.innerWidth - r.right;
    const startBottom = window.innerHeight - r.bottom;
    const move = (ev) => {
      offsetRef.current = {
        x: startRight - (ev.clientX - sx),
        y: startBottom - (ev.clientY - sy),
      };
      clampToViewport();
    };
    const up = () => {
      window.removeEventListener('mousemove', move);
      window.removeEventListener('mouseup', up);
    };
    window.addEventListener('mousemove', move);
    window.addEventListener('mouseup', up);
  };

  if (!open) return null;
  return (
    <>
      <style>{__TWEAKS_STYLE}</style>
      <div ref={dragRef} className="twk-panel"
           style={{ right: offsetRef.current.x, bottom: offsetRef.current.y }}>
        <div className="twk-hd" onMouseDown={onDragStart}>
          <b>{title}</b>
          <button className="twk-x" aria-label="Close tweaks"
                  onMouseDown={(e) => e.stopPropagation()}
                  onClick={onClose}>✕</button>
        </div>
        <div className="twk-body">
          {children}
        </div>
      </div>
    </>
  );
}

function TweakSection({ label, children }) {
  return (
    <>
      <div className="twk-sect">{label}</div>
      {children}
    </>
  );
}

function TweakRow({ label, value, children, inline = false }) {
  return (
    <div className={inline ? 'twk-row twk-row-h' : 'twk-row'}>
      <div className="twk-lbl">
        <span>{label}</span>
        {value != null && <span className="twk-val">{value}</span>}
      </div>
      {children}
    </div>
  );
}

function TweakSlider({ label, value, min = 0, max = 100, step = 1, unit = '', onChange }) {
  return (
    <TweakRow label={label} value={`${value}${unit}`}>
      <input type="range" className="twk-slider" min={min} max={max} step={step}
             value={value} onChange={(e) => onChange(Number(e.target.value))} />
    </TweakRow>
  );
}

function TweakToggle({ label, value, onChange }) {
  return (
    <div className="twk-row twk-row-h">
      <div className="twk-lbl"><span>{label}</span></div>
      <button type="button" className="twk-toggle" data-on={value ? '1' : '0'}
              role="switch" aria-checked={!!value}
              onClick={() => onChange(!value)}><i /></button>
    </div>
  );
}

function TweakSelect({ label, value, options, onChange }) {
  return (
    <TweakRow label={label}>
      <select className="twk-field" value={value} onChange={(e) => onChange(e.target.value)}>
        {options.map((o) => {
          const v = typeof o === 'object' ? o.value : o;
          const l = typeof o === 'object' ? o.label : o;
          return <option key={v} value={v}>{l}</option>;
        })}
      </select>
    </TweakRow>
  );
}

// Lightness check — accepts hex (#abc / #aabbcc) or oklch(L ...). Returns true
// if the color is light enough to need a dark checkmark drawn on top.
function __twkIsLight(color) {
  const s = String(color);
  const oklch = s.match(/oklch\(\s*([\d.]+)/);
  if (oklch) return parseFloat(oklch[1]) > 0.7;
  const h = s.replace('#', '');
  if (!/^[0-9a-f]{3,8}$/i.test(h)) return true;
  const x = h.length === 3 ? h.replace(/./g, (c) => c + c) : h.padEnd(6, '0');
  const n = parseInt(x.slice(0, 6), 16);
  if (Number.isNaN(n)) return true;
  const r = (n >> 16) & 255, g = (n >> 8) & 255, b = n & 255;
  return r * 299 + g * 587 + b * 114 > 148000;
}

const __TwkCheck = ({ light }) => (
  <svg viewBox="0 0 14 14" aria-hidden="true">
    <path d="M3 7.2 5.8 10 11 4.2" fill="none" strokeWidth="2.2"
          strokeLinecap="round" strokeLinejoin="round"
          stroke={light ? 'rgba(0,0,0,.78)' : '#fff'} />
  </svg>
);

function TweakColor({ label, value, options, onChange }) {
  const cur = String(value).toLowerCase();
  return (
    <TweakRow label={label}>
      <div className="twk-chips" role="radiogroup">
        {options.map((o, i) => {
          const on = String(o).toLowerCase() === cur;
          return (
            <button key={i} type="button" className="twk-chip" role="radio"
                    aria-checked={on} data-on={on ? '1' : '0'}
                    aria-label={String(o)} title={String(o)}
                    style={{ background: o }}
                    onClick={() => onChange(o)}>
              {on && <__TwkCheck light={__twkIsLight(o)} />}
            </button>
          );
        })}
      </div>
    </TweakRow>
  );
}

Object.assign(window, {
  useTweaks, TweaksPanel, TweakSection, TweakRow,
  TweakSlider, TweakToggle, TweakSelect, TweakColor,
});