import type { Locator, Page } from 'playwright-core';
import { expect } from 'vitest';

/**
 * Assert that an element meets the minimum touch target size (44x44px per WCAG).
 */
export async function assertMinTouchTarget(locator: Locator, minSize = 44) {
  const box = await locator.boundingBox();
  expect(box, 'Element must be visible and have a bounding box').toBeTruthy();
  expect(box!.width).toBeGreaterThanOrEqual(minSize);
  expect(box!.height).toBeGreaterThanOrEqual(minSize);
}

/**
 * Assert the gap between two elements in a given direction.
 */
export async function assertGapBetween(
  locatorA: Locator,
  locatorB: Locator,
  options: { min?: number; max?: number; direction?: 'vertical' | 'horizontal' },
) {
  const { min = 0, max = Infinity, direction = 'vertical' } = options;
  const boxA = await locatorA.boundingBox();
  const boxB = await locatorB.boundingBox();
  expect(boxA, 'Element A must be visible').toBeTruthy();
  expect(boxB, 'Element B must be visible').toBeTruthy();

  let gap: number;
  if (direction === 'vertical') {
    gap = boxB!.y - (boxA!.y + boxA!.height);
  } else {
    gap = boxB!.x - (boxA!.x + boxA!.width);
  }

  expect(gap).toBeGreaterThanOrEqual(min);
  expect(gap).toBeLessThanOrEqual(max);
}

/**
 * Assert that an element is fully within the viewport (not clipped).
 */
export async function assertWithinViewport(locator: Locator, page: Page) {
  const box = await locator.boundingBox();
  expect(box, 'Element must be visible').toBeTruthy();

  const viewport = page.viewportSize();
  expect(viewport, 'Page must have a viewport').toBeTruthy();

  expect(box!.x).toBeGreaterThanOrEqual(0);
  expect(box!.y).toBeGreaterThanOrEqual(0);
  expect(box!.x + box!.width).toBeLessThanOrEqual(viewport!.width);
  expect(box!.y + box!.height).toBeLessThanOrEqual(viewport!.height);
}