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

type LoadMetrics = {
  durationMs: number;
  transferredBytes: number;
  requestedUrls: string[];
  requestedPathCounts: Map<string, number>;
  cacheControlByPath: Map<string, string>;
  contentEncodingByPath: Map<string, string>;
};

async function mockPublicApis(page: Page): Promise<void> {
  await page.route('**/api/v1/**', async (route) => {
    const requestUrl = new URL(route.request().url());
    if (requestUrl.pathname.endsWith('/api/v1/user/me')) {
      await route.fulfill({
        status: 401,
        contentType: 'application/json',
        body: JSON.stringify({ error: 'unauthorized' }),
      });
      return;
    }

    await route.fulfill({
      status: 200,
      contentType: 'application/json',
      body: JSON.stringify({}),
    });
  });
}

async function measureSigninLoad(page: Page): Promise<LoadMetrics> {
  const requestedUrls: string[] = [];
  const requestedPathCounts = new Map<string, number>();
  const cacheControlByPath = new Map<string, string>();
  const contentEncodingByPath = new Map<string, string>();
  let transferredBytes = 0;

  const onRequest = (request: Request) => {
    const requestUrl = new URL(request.url());
    requestedUrls.push(request.url());
    if (requestUrl.protocol === 'http:' || requestUrl.protocol === 'https:') {
      const resourceKey = `${requestUrl.origin}${requestUrl.pathname}`;
      requestedPathCounts.set(
        resourceKey,
        (requestedPathCounts.get(resourceKey) ?? 0) + 1,
      );
    }
  };

  const onResponse = async (response) => {
    const url = new URL(response.url());
    const cacheControl = response.headers()['cache-control'];
    if (cacheControl) {
      cacheControlByPath.set(url.pathname, cacheControl);
    }
    const contentEncoding = response.headers()['content-encoding'];
    if (contentEncoding) {
      contentEncodingByPath.set(url.pathname, contentEncoding);
    }

    const timing = response.request().timing();
    if (timing.responseEnd >= 0) {
      const sizes = await response.request().sizes().catch(() => null);
      transferredBytes += sizes?.responseBodySize ?? 0;
    }
  };

  page.on('request', onRequest);
  page.on('response', onResponse);

  try {
    const start = performance.now();
    await page.goto('/ko/signin', { waitUntil: 'networkidle' });
    await expect(page).toHaveURL(/\/ko\/signin(?:\?.*)?$/);
    const durationMs = Math.round(performance.now() - start);

    return {
      durationMs,
      transferredBytes,
      requestedUrls,
      requestedPathCounts,
      cacheControlByPath,
      contentEncodingByPath,
    };
  } finally {
    page.off('request', onRequest);
    page.off('response', onResponse);
  }
}

function expectNoDuplicateStaticRequests(metrics: LoadMetrics): void {
  const duplicates = [...metrics.requestedPathCounts.entries()].filter(
    ([resourceKey, count]) => {
      const path = new URL(resourceKey).pathname;
      return (
        count > 1 &&
        !path.startsWith('/api/') &&
        !path.endsWith('/ko/signin') &&
        !path.endsWith('/')
      );
    },
  );
  expect(duplicates).toEqual([]);
}

test.describe('UserFront login performance budget', () => {
  test('warm login page load stays within the two second budget and reuses cached assets', async ({
    page,
  }) => {
    await mockPublicApis(page);

    const cold = await measureSigninLoad(page);
    const warm = await measureSigninLoad(page);
    console.log(
      `[userfront-perf] cold=${cold.durationMs}ms/${cold.transferredBytes}B warm=${warm.durationMs}ms/${warm.transferredBytes}B`,
    );

    expect(cold.durationMs).toBeLessThanOrEqual(1500);
    expect(warm.durationMs).toBeLessThanOrEqual(1100);
    expect(warm.transferredBytes).toBeLessThanOrEqual(1_000_000);
    expectNoDuplicateStaticRequests(cold);
    expectNoDuplicateStaticRequests(warm);
    expect(warm.requestedUrls.some((url) => url.includes('NotoSansKR'))).toBe(
      false,
    );
    expect(
      warm.requestedUrls.some((url) =>
        url.includes('fonts.googleapis.com/icon?family=Material+Icons'),
      ),
    ).toBe(false);
    expect(
      [...cold.requestedUrls, ...warm.requestedUrls].some((url) =>
        url.includes('www.gstatic.com/flutter-canvaskit'),
      ),
    ).toBe(false);
    expect(warm.requestedUrls.some((url) => url.endsWith('/assets/.env'))).toBe(
      false,
    );
    expect(
      cold.requestedUrls.some((url) =>
        url.endsWith('/flutter_service_worker.js'),
      ),
    ).toBe(false);

    const cacheControlByPath = new Map([
      ...cold.cacheControlByPath,
      ...warm.cacheControlByPath,
    ]);
    const contentEncodingByPath = new Map([
      ...cold.contentEncodingByPath,
      ...warm.contentEncodingByPath,
    ]);

    const appShellCache = cacheControlByPath.get('/ko/signin') ?? '';
    expect(appShellCache).toContain('no-cache');

    expect(cold.durationMs).toBeGreaterThanOrEqual(0);
    const brotliEntrypoint = [...contentEncodingByPath.entries()].some(
      ([path, encoding]) =>
        /^\/main\.dart\.[0-9a-f]{12}\.(?:mjs|wasm|js)$/.test(path) &&
        encoding === 'br',
    );
    expect(brotliEntrypoint).toBe(true);
    expect(contentEncodingByPath.get('/canvaskit/skwasm.wasm')).toBe('br');
  });

  test('root redirects to localized signin before Flutter boots', async ({
    page,
  }) => {
    await mockPublicApis(page);

    const requestedUrls: string[] = [];
    page.on('request', (request) => {
      requestedUrls.push(request.url());
    });

    const start = performance.now();
    await page.goto('/', { waitUntil: 'domcontentloaded' });
    await expect(page).toHaveURL(/\/ko\/signin(?:\?.*)?$/);
    const durationMs = Math.round(performance.now() - start);

    expect(durationMs).toBeLessThanOrEqual(300);
    const rootIndex = requestedUrls.findIndex(
      (url) => new URL(url).pathname === '/',
    );
    const bootstrapIndex = requestedUrls.findIndex((url) =>
      new URL(url).pathname.endsWith('/flutter_bootstrap.js'),
    );
    expect(rootIndex).toBeGreaterThanOrEqual(0);
    expect(bootstrapIndex).toBeGreaterThan(rootIndex);
  });
});