one/dist/cjs/link/prefetchIntent.cjs

One is a new React Framework that makes Vite serve both native and web.

var __defProp = Object.defineProperty;
var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
var __getOwnPropNames = Object.getOwnPropertyNames;
var __hasOwnProp = Object.prototype.hasOwnProperty;
var __export = (target, all) => {
    for (var name in all) __defProp(target, name, {
      get: all[name],
      enumerable: !0
    });
  },
  __copyProps = (to, from, except, desc) => {
    if (from && typeof from == "object" || typeof from == "function") for (let key of __getOwnPropNames(from)) !__hasOwnProp.call(to, key) && key !== except && __defProp(to, key, {
      get: () => from[key],
      enumerable: !(desc = __getOwnPropDesc(from, key)) || desc.enumerable
    });
    return to;
  };
var __toCommonJS = mod => __copyProps(__defProp({}, "__esModule", {
  value: !0
}), mod);
var prefetchIntent_exports = {};
__export(prefetchIntent_exports, {
  createPrefetchIntent: () => createPrefetchIntent,
  observePrefetchIntent: () => observePrefetchIntent,
  startPrefetchIntent: () => startPrefetchIntent
});
module.exports = __toCommonJS(prefetchIntent_exports);
function createPrefetchIntent(options) {
  const {
      onPrefetch,
      maxReach = 500,
      perpWeight = 5,
      minSpeed = 8
    } = options,
    done = /* @__PURE__ */new Set();
  let rects = [],
    px = 0,
    py = 0,
    vx = 0,
    vy = 0,
    moveCount = 0,
    lastPrefetchMove = 0;
  function setRects(newRects) {
    rects = newRects.filter(r => !done.has(r.h));
  }
  function move(x, y, dx, dy) {
    moveCount++;
    const smooth = moveCount < 3 ? 0.3 : 0.6;
    vx = vx * smooth + dx * (1 - smooth), vy = vy * smooth + dy * (1 - smooth), px = x, py = y;
    const speed = Math.sqrt(vx * vx + vy * vy);
    if (speed < minSpeed) return;
    const ux = vx / speed,
      uy = vy / speed;
    let best = 1 / 0,
      href = "";
    for (const {
      r,
      h
    } of rects) {
      const cx = (r.left + r.right) / 2 - px,
        cy = (r.top + r.bottom) / 2 - py,
        dist = Math.sqrt(cx * cx + cy * cy),
        along = cx * ux + cy * uy;
      if (along < 0) continue;
      const perpX = cx - along * ux,
        perpY = cy - along * uy,
        perp = Math.sqrt(perpX * perpX + perpY * perpY),
        baseRadius = Math.max(r.width, r.height) / 2 + 30,
        distanceFactor = Math.max(0.2, 1 - dist / 1e3),
        radius = baseRadius * distanceFactor + 20;
      if (perp > radius) continue;
      const score = along + perp * perpWeight;
      score < best && (best = score, href = h);
    }
    href && best < maxReach && moveCount - lastPrefetchMove > 1 && (done.add(href), rects = rects.filter(r => r.h !== href), lastPrefetchMove = moveCount, onPrefetch(href));
  }
  const nodes = /* @__PURE__ */new Map();
  function observe(el, href) {
    return nodes.set(el, href), () => {
      nodes.delete(el), done.delete(href);
    };
  }
  return {
    setRects,
    move,
    observe,
    nodes,
    done
  };
}
let instance = null,
  started = !1;
function startPrefetchIntent(onPrefetch) {
  if (started) return instance;
  started = !0, instance = createPrefetchIntent({
    onPrefetch
  });
  let frame = 0,
    px = 0,
    py = 0;
  function measure() {
    if (!instance.nodes.size) return setTimeout(measure, 300);
    const io = new IntersectionObserver(entries => {
      io.disconnect(), instance.setRects(entries.filter(e => e.isIntersecting).map(e => ({
        r: e.boundingClientRect,
        h: instance.nodes.get(e.target)
      })).filter(x => x.h)), setTimeout(measure, 300);
    });
    instance.nodes.forEach((_, el) => io.observe(el));
  }
  return measure(), document.addEventListener("mousemove", e => {
    if (++frame % 4) return;
    const dx = e.clientX - px,
      dy = e.clientY - py;
    px = e.clientX, py = e.clientY, instance.move(px, py, dx, dy);
  }, {
    passive: !0
  }), instance;
}
function observePrefetchIntent(el, href) {
  return instance ? instance.observe(el, href) : () => {};
}