// What the refresh spinner shows: on at once, off only after a minimum time.
import assert from "node:assert/strict";
import { test } from "node:test";
import { createBusyHold } from "../src/ui/polled/busy-hold.ts";

// A clock and a timer the test moves by hand.
function rig() {
  let t = 0;
  const timers = [];
  const shown = [];
  const hold = createBusyHold({
    show: (s) => shown.push(s),
    minMs: 400,
    now: () => t,
    after: (fn, ms) => {
      const timer = { fn, at: t + ms, live: true };
      timers.push(timer);
      return timer;
    },
    cancel: (timer) => {
      timer.live = false;
    },
  });
  const advance = (ms) => {
    t += ms;
    for (const timer of timers) {
      if (timer.live && timer.at <= t) {
        timer.live = false;
        timer.fn();
      }
    }
  };
  return { hold, shown, advance };
}

test("it turns on at once and, for a quick answer, off only after the minimum", () => {
  const { hold, shown, advance } = rig();
  hold.busy(true);
  assert.deepEqual(shown, [true]);
  advance(50);
  hold.busy(false);
  assert.deepEqual(shown, [true]);
  advance(349);
  assert.deepEqual(shown, [true]);
  advance(1);
  assert.deepEqual(shown, [true, false]);
});

test("a slow answer turns it off as soon as it arrives", () => {
  const { hold, shown, advance } = rig();
  hold.busy(true);
  advance(900);
  hold.busy(false);
  assert.deepEqual(shown, [true, false]);
});

test("a new request while it is held keeps it on and cancels the pending off", () => {
  const { hold, shown, advance } = rig();
  hold.busy(true);
  advance(100);
  hold.busy(false);
  hold.busy(true);
  advance(1000);
  assert.deepEqual(shown, [true]);
  hold.busy(false);
  assert.deepEqual(shown, [true, false]);
});

test("stop drops a pending off, and busy(false) with nothing shown does nothing", () => {
  const { hold, shown, advance } = rig();
  hold.busy(false);
  hold.busy(true);
  hold.busy(false);
  hold.stop();
  advance(1000);
  assert.deepEqual(shown, [true]);
});