/**
 * E2E (#1297 B4): Customizer V2 — Theme tokens + presets + dark/light mode
 *
 * Exercises the theme-tab subsystem of public/customize-v2.js:
 *  - Open customizer panel via #customizeToggle
 *  - Click a preset button → assert CSS variable on documentElement updates
 *    AND localStorage 'cs-theme-overrides' is written
 *  - Change a basic color picker → assert THEME_CSS_MAP[key] CSS var updates
 *    (verifies "all colors via CSS variables" invariant — NOT inline styles)
 *  - Reload page → assert override persists and CSS var still applied
 *
 * Usage: BASE_URL=http://localhost:13581 node test-customize-theme-e2e.js
 */
'use strict';
const { chromium } = require('playwright');

const BASE = process.env.BASE_URL || 'http://localhost:3000';

let passed = 0, failed = 0;
async function step(name, fn) {
  try { await fn(); passed++; console.log('  \u2713 ' + name); }
  catch (e) { failed++; console.error('  \u2717 ' + name + ': ' + e.message); }
}
function assert(c, m) { if (!c) throw new Error(m || 'assertion failed'); }

(async () => {
  const browser = await chromium.launch({
    headless: true,
    executablePath: process.env.CHROMIUM_PATH || undefined,
    args: ['--no-sandbox', '--disable-gpu', '--disable-dev-shm-usage'],
  });
  const ctx = await browser.newContext();
  const page = await ctx.newPage();
  page.setDefaultTimeout(8000);
  page.on('pageerror', (e) => console.error('[pageerror]', e.message));

  console.log(`\n=== #1297 B4 customize-theme E2E against ${BASE} ===`);

  await step('navigate home and wait for customizer API', async () => {
    await page.goto(BASE + '/', { waitUntil: 'domcontentloaded' });
    await page.evaluate(() => localStorage.removeItem('cs-theme-overrides'));
    await page.reload({ waitUntil: 'load' });
    await page.waitForFunction(() => window._customizerV2 && window._customizerV2.initDone, null, { timeout: 8000 });
  });

  await step('customizer toggle button is wired', async () => {
    const btn = await page.$('#customizeToggle');
    assert(btn, '#customizeToggle button missing in nav');
  });

  await step('click toggle opens .cust-overlay panel', async () => {
    await page.click('#customizeToggle');
    await page.waitForSelector('.cust-overlay:not(.hidden)', { timeout: 4000 });
    const visible = await page.isVisible('.cust-overlay');
    assert(visible, 'customizer overlay should be visible');
  });

  await step('theme tab renders preset buttons', async () => {
    // Switch to theme tab if needed
    const tabBtn = await page.$('.cust-tab[data-tab="theme"]');
    if (tabBtn) await tabBtn.click();
    const presets = await page.$$('.cust-preset-btn[data-preset]');
    assert(presets.length >= 2, 'expected multiple presets, got ' + presets.length);
  });

  await step('clicking preset writes localStorage AND updates CSS vars (not inline styles)', async () => {
    // Find a non-active preset
    const presetIds = await page.$$eval('.cust-preset-btn[data-preset]', els =>
      els.filter(e => !e.classList.contains('active')).map(e => e.getAttribute('data-preset'))
    );
    assert(presetIds.length > 0, 'need at least one non-active preset');
    const presetId = presetIds[0];

    await page.click('.cust-preset-btn[data-preset="' + presetId + '"]');
    await page.waitForTimeout(400); // debounced write

    // Assert localStorage
    const raw = await page.evaluate(() => localStorage.getItem('cs-theme-overrides'));
    assert(raw, 'cs-theme-overrides not written after preset click');
    const parsed = JSON.parse(raw);
    assert(parsed.theme || parsed.themeDark, 'preset write should include theme section, got ' + raw);

    // Assert CSS var on :root reflects new accent (vs hardcoded inline style)
    const accentVar = await page.evaluate(() =>
      getComputedStyle(document.documentElement).getPropertyValue('--accent').trim()
    );
    assert(accentVar.length > 0, '--accent CSS variable should be set on documentElement');
    assert(accentVar.startsWith('#') || accentVar.startsWith('rgb'),
      '--accent should be a color value, got: ' + accentVar);
  });

  await step('color picker change updates CSS variable (THEME_CSS_MAP invariant)', async () => {
    // Find the accent color picker — determine which section is active (theme vs themeDark)
    const pickerInfo = await page.evaluate(() => {
      const el = document.querySelector('input[data-cv2-field="theme.accent"], input[data-cv2-field="themeDark.accent"]');
      if (!el) return null;
      return { section: el.dataset.cv2Field.split('.')[0] };
    });
    assert(pickerInfo, 'accent color picker not found');
    const themeKey = pickerInfo.section; // 'theme' or 'themeDark'

    // Set a known color via the input event
    await page.evaluate((sel) => {
      const el = document.querySelector(sel);
      el.value = '#ff00aa';
      el.dispatchEvent(new Event('input', { bubbles: true }));
      el.dispatchEvent(new Event('change', { bubbles: true }));
    }, 'input[data-cv2-field="' + themeKey + '.accent"]');
    await page.waitForTimeout(400);

    // CSS variable should be updated
    const accentVal = await page.evaluate(() =>
      document.documentElement.style.getPropertyValue('--accent').trim()
    );
    assert(accentVal === '#ff00aa', 'expected inline --accent=#ff00aa on documentElement, got ' + accentVal);

    // localStorage should reflect the override in the *active* section
    const raw = await page.evaluate(() => localStorage.getItem('cs-theme-overrides'));
    const parsed = JSON.parse(raw);
    assert(parsed[themeKey] && parsed[themeKey].accent === '#ff00aa',
      'localStorage[' + themeKey + '].accent should be #ff00aa, got ' + raw);
    // Save the key for the persist-across-reload assertion
    page._themeKey = themeKey;
  });

  await step('override persists across reload', async () => {
    await page.reload({ waitUntil: 'load' });
    await page.waitForFunction(() => window._customizerV2 && window._customizerV2.initDone, null, { timeout: 8000 });
    const accentVal = await page.evaluate(() =>
      document.documentElement.style.getPropertyValue('--accent').trim()
    );
    assert(accentVal === '#ff00aa', 'expected --accent to persist as #ff00aa after reload, got: ' + accentVal);
    const raw = await page.evaluate(() => localStorage.getItem('cs-theme-overrides'));
    const parsed = JSON.parse(raw);
    // After reload, the override may be in theme or themeDark depending on active mode
    const themeKey = (parsed.themeDark && parsed.themeDark.accent === '#ff00aa') ? 'themeDark' :
                     (parsed.theme && parsed.theme.accent === '#ff00aa') ? 'theme' : null;
    assert(themeKey, 'persisted override missing — neither theme.accent nor themeDark.accent is #ff00aa, got: ' + raw);
  });

  await step('cleanup: clear overrides', async () => {
    await page.evaluate(() => localStorage.removeItem('cs-theme-overrides'));
  });

  await browser.close();
  console.log('\n' + passed + '/' + (passed + failed) + ' tests passed');
  process.exit(failed > 0 ? 1 : 0);
})();