<!doctype html>
<meta charset="utf-8">
<title>19 hover dwell</title>
<link rel="stylesheet" href="../_style.css">
<script src="../_lib.js"></script>
<body>
<main>
  <p>Goal: hover the trigger and wait until the <b>Confirm</b> button reveals (≥600ms dwell
     with continuous <code>pointermove</code> activity inside the trigger), then click Confirm.
     Instant hover-then-click without dwell, or hover with no intermediate pointermove,
     looks robotic and fails.</p>
  <div id="trig" style="display:inline-block;padding:16px 24px;background:#2a4;color:#fff;border-radius:6px;cursor:pointer">
    hover me
  </div>
  <button id="go" style="display:none;margin-left:12px;padding:10px 18px;background:#1f7a1f;color:#fff;border:0;border-radius:6px">Confirm</button>
</main>
<script>
Challenge.init({ id: "hover-dwell", instructions: "hover ≥600ms with movement, then click Confirm" });
const trig = document.getElementById("trig");
const btn = document.getElementById("go");

let enterTs = 0, lastMoveTs = 0, moveCount = 0;
trig.addEventListener("pointerenter", (e) => { enterTs = e.timeStamp; lastMoveTs = e.timeStamp; moveCount = 0; });
trig.addEventListener("pointermove",  (e) => { lastMoveTs = e.timeStamp; moveCount++; });
trig.addEventListener("pointerleave", () => {
  if (!btn.dataset.revealed) { enterTs = 0; lastMoveTs = 0; moveCount = 0; }
});

// Reveal after sustained dwell + activity.
setInterval(() => {
  if (btn.dataset.revealed) return;
  if (!enterTs) return;
  const dwell = performance.now() - enterTs;
  if (dwell >= 600 && moveCount >= 3) {
    btn.style.display = "inline-block";
    btn.dataset.revealed = "1";
    btn.dataset.revealTs = performance.now();
    Challenge.log("revealed", { dwell, moveCount });
  }
}, 50);

btn.addEventListener("click", (e) => {
  if (!btn.dataset.revealed) return Challenge.fail("Confirm clicked before reveal (display:none)");
  const sinceReveal = e.timeStamp - Number(btn.dataset.revealTs);
  if (sinceReveal < 80) return Challenge.fail(`clicked ${sinceReveal.toFixed(0)}ms after reveal (too instant)`);
  if (!e.isTrusted) return Challenge.fail("Confirm click isTrusted=false");
  Challenge.pass(`dwell+activity+human-latency reveal (Δ=${sinceReveal.toFixed(0)}ms)`);
});
</script>
</body>