import { type Page, expect, test } from '@playwright/test';

import { scriptMarker, seedScript } from '../utils/seedScript';

/**
 * The note field is the script source throughout, so that these tests do not
 * depend on how custom field keys happen to be spelled.
 */
const teleprompterUrl = '/teleprompter?script=note';

function scroller(page: Page) {
  return page.getByTestId('teleprompter-scroller');
}

function scrollTop(page: Page) {
  return scroller(page).evaluate((element) => element.scrollTop);
}

test.describe('teleprompter', () => {
  test.beforeEach(async ({ page }) => {
    await seedScript(page);
  });

  test('shows the script from the selected source', async ({ page }) => {
    await page.goto(teleprompterUrl);

    await expect(page.getByTestId('teleprompter-view')).toBeVisible();
    await expect(scroller(page)).toBeVisible();
    await expect(page.getByText(scriptMarker).first()).toBeVisible();
  });

  test('asks for a script source when none is selected', async ({ page }) => {
    await page.goto('/teleprompter');

    await expect(page.getByTestId('teleprompter-view')).toBeVisible();
    await expect(page.getByText('Select which field holds the script in the view options')).toBeVisible();
  });

  test('space starts and stops the scroll', async ({ page }) => {
    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();

    expect(await scrollTop(page)).toBe(0);

    await page.keyboard.press('Space');
    await expect.poll(() => scrollTop(page)).toBeGreaterThan(0);

    await page.keyboard.press('Space');
    await page.waitForTimeout(200);
    const afterPause = await scrollTop(page);
    await page.waitForTimeout(500);

    expect(await scrollTop(page)).toBe(afterPause);
  });

  test('space drives playback instead of opening the navigation menu', async ({ page }) => {
    // the navigation menu binds Space globally, the teleprompter claims it back
    await page.goto('/timer');
    await expect(page.locator('data-testid=timer-view')).toBeVisible();
    await page.keyboard.press('Space');
    await expect(page.getByRole('dialog')).toBeVisible();

    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();
    await page.keyboard.press('Space');
    await expect(page.getByRole('dialog')).toHaveCount(0);

    // and the claim is released once the view goes away
    await page.goto('/timer');
    await expect(page.locator('data-testid=timer-view')).toBeVisible();
    await page.keyboard.press('Space');
    await expect(page.getByRole('dialog')).toBeVisible();
  });

  test('arrow keys nudge and home rewinds', async ({ page }) => {
    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();

    await page.keyboard.press('ArrowDown');
    await page.keyboard.press('ArrowDown');
    await expect.poll(() => scrollTop(page)).toBeGreaterThan(0);

    // the rewind eases rather than snapping, so poll rather than guess a duration
    await page.keyboard.press('Home');
    await expect.poll(() => scrollTop(page)).toBe(0);
  });

  test('keeps a scroll it did not make itself', async ({ page }) => {
    // the animation frame loop runs for the lifetime of the view, so it has to
    // notice when something else moves the scroller, otherwise a scrollbar drag
    // or find in page would be snapped back on the next frame
    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();

    await scroller(page).evaluate((element) => {
      element.scrollTop = 400;
    });

    await page.waitForTimeout(500);
    expect(await scrollTop(page)).toBe(400);
  });

  test('arrow keys change the speed', async ({ page }) => {
    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();

    const readout = page.getByTestId('teleprompter-speed');
    const before = Number(await readout.innerText().then((text) => text.replace(/\D/g, '')));

    await page.keyboard.press('ArrowRight');
    const faster = Number(await readout.innerText().then((text) => text.replace(/\D/g, '')));
    expect(faster).toBeGreaterThan(before);

    await page.keyboard.press('ArrowLeft');
    const slower = Number(await readout.innerText().then((text) => text.replace(/\D/g, '')));
    expect(slower).toBe(before);
  });

  test('f mirrors the view for a beam splitter rig', async ({ page }) => {
    await page.goto(teleprompterUrl);
    await expect(scroller(page)).toBeVisible();

    const view = page.getByTestId('teleprompter-view');
    await page.keyboard.press('f');

    // a horizontal flip is a negative x scale in the computed matrix
    const transform = await view.evaluate((element) => getComputedStyle(element).transform);
    expect(transform.startsWith('matrix(-1')).toBe(true);
  });

  test('honours the flip and reading line params', async ({ page }) => {
    await page.goto('/teleprompter?script=note&flipV=true&readingLine=false');

    const view = page.getByTestId('teleprompter-view');
    const transform = await view.evaluate((element) => getComputedStyle(element).transform);
    // a vertical flip leaves x positive and makes the y scale negative
    expect(transform).toMatch(/^matrix\(1, 0, 0, -1/);

    // a boolean which defaults to true has to be switchable off from the url
    await expect(page.locator('.teleprompter__reading-marker')).toHaveCount(0);
  });
});