scrabble-game/ui/e2e/zoom.spec.ts

import { expect, test } from './fixtures';

// Item 5: zooming the board must enlarge the labels too (a magnifying-glass zoom).
// cqw is sized against the zoom-scaled board, so the font grows with the cells.
test('zoom enlarges the board labels with the board', async ({ page }) => {
  await page.goto('/');
  await page.getByRole('button', { name: /guest/i }).click();
  await page.getByRole('button', { name: /Ann/ }).click();

  const letter = page.locator('[data-cell] .letter').first();
  await expect(letter).toBeVisible();
  const base = await letter.evaluate((el) => parseFloat(getComputedStyle(el).fontSize));

  // Double-tap an empty cell to zoom in (two synchronous clicks = a double-tap).
  await page
    .locator('[data-cell]:not(.filled)')
    .nth(20)
    .evaluate((el: HTMLElement) => {
      el.click();
      el.click();
    });
  await page.waitForTimeout(400); // let the width transition settle

  const zoomed = await letter.evaluate((el) => parseFloat(getComputedStyle(el).fontSize));
  expect(zoomed).toBeGreaterThan(base * 1.4);
});

// Item 4 (UX): the zoomed board clamps at its edge — no native rubber-band/overscroll past
// the content. We assert the CSS contract on the zoomed scroll container, which is
// deterministic across engines (the bounce gesture itself is a native compositor behaviour
// Playwright cannot reliably synthesize).
test('zoomed board clamps overscroll at the edge', async ({ page }) => {
  await page.goto('/');
  await page.getByRole('button', { name: /guest/i }).click();
  await page.getByRole('button', { name: /Ann/ }).click();

  // Double-tap an empty cell to zoom in.
  await page
    .locator('[data-cell]:not(.filled)')
    .nth(20)
    .evaluate((el: HTMLElement) => {
      el.click();
      el.click();
    });

  const viewport = page.locator('.viewport.zoomed');
  await expect(viewport).toBeVisible();
  const ob = await viewport.evaluate((el) => {
    const s = getComputedStyle(el);
    return { x: s.overscrollBehaviorX, y: s.overscrollBehaviorY };
  });
  expect(ob.x).toBe('none');
  expect(ob.y).toBe('none');
});

// A hint taken while the board is ALREADY zoomed in must still scroll to the played word — the
// zoom state does not change, so without an explicit recenter the board stays parked where the
// player was looking (the reported rough edge). The mock hint plays at the centre star (7,7), so
// zooming into the top-left corner first and then hinting must pan the board toward the centre.
test('a hint recentres an already-zoomed board on the played word', async ({ page }) => {
  await page.goto('/');
  await page.getByRole('button', { name: /guest/i }).click();
  await page.getByRole('button', { name: /Ann/ }).click();

  // Zoom into the top-left cell (far from the centre where the hint lands).
  await page
    .locator('[data-cell]:not(.filled)')
    .first()
    .evaluate((el: HTMLElement) => {
      el.click();
      el.click();
    });
  const viewport = page.locator('.viewport.zoomed');
  await expect(viewport).toBeVisible();
  await page.waitForTimeout(400); // let the zoom-in settle near the top-left corner
  const before = await viewport.evaluate((el) => ({ left: el.scrollLeft, top: el.scrollTop }));

  // Take a hint (the control confirms on a second tap), which plays at the centre.
  const hint = page.getByRole('button', { name: 'Hint' });
  await hint.click();
  await hint.click();
  await page.waitForTimeout(300); // the board pans to the hint word

  const after = await viewport.evaluate((el) => ({ left: el.scrollLeft, top: el.scrollTop }));
  // The board panned from the top-left toward the centre word: both offsets grew.
  expect(after.left).toBeGreaterThan(before.left + 20);
  expect(after.top).toBeGreaterThan(before.top + 20);
});