import { test, expect } from '@playwright/test';
import { TEST_CONFIG } from '../../utils/test-helpers';

/** Pixel-perfect visual regression: strict by default. Relax in CI if needed via VISUAL_MAX_DIFF_PIXELS. */
const MAX_DIFF_PIXELS = process.env.VISUAL_MAX_DIFF_PIXELS ? parseInt(process.env.VISUAL_MAX_DIFF_PIXELS, 10) : 0;
const ANIMATION_SETTLE_MS = 800;

async function ensureDarkTheme(page: import('@playwright/test').Page) {
  await page.evaluate(() => {
    document.documentElement.classList.add('dark');
    document.documentElement.setAttribute('data-theme', 'dark');
  });
  await page.waitForTimeout(100);
}

test.describe('Visual regression (pixel-perfect)', () => {
  test.beforeEach(async ({ page }) => {
    await page.emulateMedia({ reducedMotion: 'reduce' });
  });

  test.describe('Auth pages (no storage)', () => {
    test.use({ storageState: { cookies: [], origins: [] } });

    test('login page', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/login`);
      await page.waitForLoadState('networkidle');
      await page.waitForSelector('form', { timeout: 10000 });
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(page).toHaveScreenshot('login-page.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('register page', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/register`);
      await page.waitForLoadState('networkidle');
      await page.waitForSelector('form, [role="form"], input[type="email"]', { timeout: 15000 }).catch(() => {});
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(page).toHaveScreenshot('register-page.png', {
        fullPage: true,
        maxDiffPixels: Math.max(MAX_DIFF_PIXELS, 10), // allow minor font/subpixel variance
      });
    });
  });

  test.describe('App shell (authenticated)', () => {
    test('dashboard full page', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      await page.waitForSelector('main, [role="main"]', { timeout: 15000 });
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(page).toHaveScreenshot('dashboard-full.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('dashboard header only', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      const header = page.locator('header').first();
      await header.waitFor({ timeout: 10000 });
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(header).toHaveScreenshot('dashboard-header.png', {
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('dashboard sidebar only', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      const sidebar = page.locator('aside').first();
      const visible = await sidebar.waitFor({ state: 'visible', timeout: 12000 }).then(() => true).catch(() => false);
      if (!visible) {
        test.skip(true, 'Sidebar not visible (e.g. not authenticated or mobile layout)');
        return;
      }
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(sidebar).toHaveScreenshot('dashboard-sidebar.png', {
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('global player bar', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      const playerBar = page.locator('div.fixed.bottom-0.left-0.right-0').first();
      await playerBar.waitFor({ state: 'visible', timeout: 5000 }).catch(() => {});
      if ((await playerBar.count()) === 0) {
        test.skip();
        return;
      }
      await expect(playerBar).toHaveScreenshot('player-bar.png', {
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });
  });

  test.describe('Key routes', () => {
    test('playlists page', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/playlists`);
      await page.waitForLoadState('networkidle');
      await page.waitForSelector('main, [role="main"]', { timeout: 10000 }).catch(() => {});
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(page).toHaveScreenshot('playlists-page.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('404 page', async ({ page }) => {
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/non-existent-route-404`);
      await page.waitForLoadState('networkidle');
      await ensureDarkTheme(page);
      await page.waitForTimeout(ANIMATION_SETTLE_MS);

      await expect(page).toHaveScreenshot('404-page.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });
  });

  test.describe('Viewports', () => {
    test('dashboard mobile 375x667', async ({ page }) => {
      await page.setViewportSize({ width: 375, height: 667 });
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      await page.waitForTimeout(ANIMATION_SETTLE_MS);
      await ensureDarkTheme(page);

      await expect(page).toHaveScreenshot('dashboard-mobile.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });

    test('dashboard tablet 768x1024', async ({ page }) => {
      await page.setViewportSize({ width: 768, height: 1024 });
      await page.goto(`${TEST_CONFIG.FRONTEND_URL}/dashboard`);
      await page.waitForLoadState('networkidle');
      await page.waitForTimeout(ANIMATION_SETTLE_MS);
      await ensureDarkTheme(page);

      await expect(page).toHaveScreenshot('dashboard-tablet.png', {
        fullPage: true,
        maxDiffPixels: MAX_DIFF_PIXELS,
      });
    });
  });
});