// Storybook regression for the Chart Only change. Compares this worktree's
// Storybook (STORYBOOK_URL) with a baseline Storybook (BASELINE_URL, optional)
// and checks that Expanded keeps its controls and Ctrl/⌘ + wheel policy.
import assert from 'node:assert/strict';
import path from 'node:path';
import { mkdir, writeFile } from 'node:fs/promises';
import { fileURLToPath } from 'node:url';
import { launchChromium } from '../../scripts/orgchart-browser-runtime.mjs';

const root = fileURLToPath(new URL('../../', import.meta.url));
const output = path.join(root, 'test-results/org-chart-chart-only/storybook');
await mkdir(output, { recursive: true });
const target = process.env.STORYBOOK_URL ?? 'http://127.0.0.1:6044';
const baseline = process.env.BASELINE_URL;
const browser = await launchChromium();
const context = await browser.newContext({ viewport: { width: 1440, height: 1000 }, deviceScaleFactor: 1 });
const results = [];
const consoleErrors = [];
const wheelOnly = process.argv.includes('--wheel-only');
const record = (name, pass, detail) => { results.push({ name, pass, detail }); console.log(`${pass ? 'PASS' : 'FAIL'} ${name}`, detail === undefined ? '' : JSON.stringify(detail)); };
const check = async (name, fn) => { try { record(name, true, await fn()); } catch (error) { record(name, false, error.message); } };
const stories = ['orgchart--logo-personnel-summary', 'orgchart--department-colors', 'orgchart--full-composition', 'orgchart--expanded-org-chart'];

async function open(origin, id) {
  const page = await context.newPage();
  page.on('console', message => { if (message.type() === 'error') consoleErrors.push({ origin, id, text: message.text() }); });
  page.on('pageerror', error => consoleErrors.push({ origin, id, text: String(error) }));
  await page.goto(`${origin}/iframe.html?id=${id}&viewMode=story`);
  await page.waitForFunction(() => {
    const hosts = [...document.querySelectorAll('.hm-orgchart-host')];
    // Overview renders summaries without an OrgChart host.
    return document.getElementById('storybook-root')?.childElementCount && hosts.every(host => host.shadowRoot?.querySelector('.hm-orgchart-shell')?.getAttribute('aria-busy') === 'false');
  }, null, { timeout: 60000 });
  await page.evaluate(() => document.fonts.ready);
  await page.waitForTimeout(800);
  return page;
}
/** Story DOM plus every OrgChart shadow root, without instance/React IDs. */
const snapshot = page => page.evaluate(() => [document.getElementById('storybook-root').innerHTML,
  ...[...document.querySelectorAll('.hm-orgchart-host')].map(host => host.shadowRoot.innerHTML)].join('\n')
  .replace(/hm-orgchart-\d+/g, 'hm-orgchart-N').replace(/«[^»]*»|_r_[0-9a-z]+_/g, 'react-id'));

async function pixelDiff(a, b) {
  const page = await context.newPage();
  const result = await page.evaluate(async ([ua, ub]) => {
    const load = src => new Promise(resolve => { const image = new Image(); image.onload = () => resolve(image); image.src = src; });
    const [ia, ib] = await Promise.all([load(ua), load(ub)]);
    if (ia.width !== ib.width || ia.height !== ib.height) return { size: [ia.width, ia.height, ib.width, ib.height], diffPixels: Infinity };
    const read = image => { const canvas = document.createElement('canvas'); canvas.width = image.width; canvas.height = image.height; const c = canvas.getContext('2d'); c.drawImage(image, 0, 0); return c.getImageData(0, 0, image.width, image.height).data; };
    const da = read(ia), db = read(ib); let diffPixels = 0, maxDelta = 0; const box = [Infinity, Infinity, -1, -1];
    for (let i = 0; i < da.length; i += 4) {
      const delta = Math.max(Math.abs(da[i] - db[i]), Math.abs(da[i + 1] - db[i + 1]), Math.abs(da[i + 2] - db[i + 2]));
      if (!delta) continue;
      diffPixels++; maxDelta = Math.max(maxDelta, delta);
      const p = i / 4, x = p % ia.width, y = Math.floor(p / ia.width);
      box[0] = Math.min(box[0], x); box[1] = Math.min(box[1], y); box[2] = Math.max(box[2], x); box[3] = Math.max(box[3], y);
    }
    return { size: [ia.width, ia.height], diffPixels, maxDelta, box };
  }, [`data:image/png;base64,${a.toString('base64')}`, `data:image/png;base64,${b.toString('base64')}`]);
  await page.close();
  return result;
}

const index = await (await fetch(`${target}/index.json`)).json();
if (!wheelOnly) await check('Storybook OrgChart public menus', () => {
  const visible = Object.values(index.entries).filter(entry => entry.title.startsWith('OrgChart/') && !(entry.tags ?? []).includes('internal')).map(entry => `${entry.title} › ${entry.name}`);
  assert.deepEqual(visible.sort(), ['OrgChart/Department Colors › Department Colors', 'OrgChart/Expanded OrgChart › Expanded OrgChart', 'OrgChart/Full Composition › Full Composition', 'OrgChart/Overview › Overview']);
  return visible;
});

for (const id of wheelOnly ? ['orgchart--expanded-org-chart'] : stories) {
  const page = await open(target, id);
  const buffer = await page.screenshot({ path: path.join(output, `${id}.png`), fullPage: true });
  const dom = await snapshot(page);
  if (baseline) {
    const reference = await open(baseline, id);
    const referenceBuffer = await reference.screenshot({ path: path.join(output, `${id}.baseline.png`), fullPage: true });
    const referenceDom = await snapshot(reference);
    // Pixel identity is reported, not assumed: when it differs, a second
    // baseline capture shows whether the baseline itself is deterministic.
    const pixels = buffer.equals(referenceBuffer) ? { identical: true } : {
      target: await pixelDiff(buffer, referenceBuffer),
      baselineSelf: await pixelDiff(referenceBuffer, await (await open(baseline, id)).screenshot({ fullPage: true })),
    };
    await check(`${id} matches baseline (DOM + pixels)`, () => {
      assert.equal(dom, referenceDom, 'shadow DOM differs');
      // Identical DOM with a handful of ±1 channel pixels is rasterization
      // jitter of the scaled Fixed stage, not a design change.
      if (!pixels.identical) assert.ok(pixels.target.diffPixels <= 50 && pixels.target.maxDelta <= 2, `pixel diff ${JSON.stringify(pixels)}`);
      return { domLength: dom.length, pixels };
    });
    await reference.close();
  }
  if (id === 'orgchart--expanded-org-chart') {
    const state = () => page.evaluate(() => {
      const sr = document.querySelector('.hm-orgchart-host').shadowRoot;
      const vp = sr.querySelector('.hm-orgchart-viewport');
      return { scale: +vp.dataset.scale, x: +vp.dataset.panX, y: +vp.dataset.panY,
        heading: sr.querySelector('.hm-orgchart-title')?.textContent, date: sr.querySelector('.hm-orgchart-date')?.textContent,
        selection: sr.querySelector('.hm-orgchart-expanded-selection')?.textContent,
        toolbar: [...sr.querySelectorAll('.hm-orgchart-expanded-toolbar > *')].map(e => e.textContent),
        feedback: sr.querySelector('.hm-orgchart-move-feedback')?.textContent, presentation: sr.querySelector('.hm-orgchart-shell').dataset.presentationMode ?? null };
    });
    const before = await state();
    if (!wheelOnly) await check('Expanded keeps heading, date, summary, toolbar and guidance', () => {
      assert.equal(before.presentation, null);
      assert.ok(before.heading && before.date?.startsWith('기준일') && before.selection?.startsWith('선택'));
      assert.deepEqual(before.toolbar.slice(0, 4), ['확대', '축소', '100% 복원', 'Fit to View']);
      assert.match(before.toolbar[4], /^\d+%$/);
      assert.equal(before.toolbar[5], '드래그·방향키 이동 · Ctrl/⌘ + 휠 확대');
      assert.match(before.feedback, /Drag & Drop OFF/);
      return before;
    });
    const canvas = page.locator('.hm-orgchart-viewport');
    await canvas.evaluate(element => element.scrollIntoView({ block: 'center', behavior: 'instant' }));
    const box = await canvas.boundingBox();
    await page.mouse.move(box.x + box.width / 2, box.y + box.height / 2);
    await page.mouse.wheel(0, -100);
    await page.waitForTimeout(150);
    const plain = await state();
    const plainScroll = await page.evaluate(() => scrollY);
    // A plain wheel scrolls the story page; aim at the canvas again.
    await canvas.evaluate(element => element.scrollIntoView({ block: 'center', behavior: 'instant' }));
    const moved = await canvas.boundingBox();
    await page.mouse.move(moved.x + moved.width / 2, moved.y + moved.height / 2);
    await page.keyboard.down('Control'); await page.mouse.wheel(0, -100); await page.keyboard.up('Control');
    await page.waitForTimeout(150);
    const ctrl = await state();
    await check('Expanded plain wheel does not zoom; Ctrl + wheel zooms', () => {
      assert.equal(plain.scale, before.scale);
      assert.ok(ctrl.scale > plain.scale);
      return { before: before.scale, plain: plain.scale, ctrl: +ctrl.scale.toFixed(4), pageScrolledByPlainWheel: plainScroll };
    });
    if (!wheelOnly) {
      await page.getByRole('button', { name: 'Fit to View' }).click();
      const fitted = await state();
      await check('Expanded Fit to View button still works', () => { assert.ok(fitted.scale <= 1 && fitted.scale !== ctrl.scale); return { scale: +fitted.scale.toFixed(4) }; });
    }
  }
  if (id === 'orgchart--full-composition') {
    await check('Full Composition keeps Fixed composition', () => page.evaluate(() => {
      const shells = [...document.querySelectorAll('.hm-orgchart-host')].map(host => host.shadowRoot.querySelector('.hm-orgchart-shell'));
      if (!shells.length || shells.some(shell => shell.dataset.presentationMode)) throw new Error('unexpected presentation mode');
      return shells.map(shell => ({ layout: shell.dataset.layoutMode, heading: !!shell.querySelector('.hm-orgchart-heading'), stage: !!shell.querySelector('.hm-orgchart-stage') }));
    }));
  }
  await page.close();
}
await browser.close();
const failed = results.filter(result => !result.pass);
await writeFile(path.join(output, wheelOnly ? 'results-wheel.json' : 'results.json'), JSON.stringify({ target, baseline, results, consoleErrors }, null, 2));
console.log(`\n${results.length - failed.length}/${results.length} PASS · console errors ${consoleErrors.length}`);
for (const error of consoleErrors) console.log('console:', error.origin, error.id, error.text);
if (failed.length || consoleErrors.length) process.exitCode = 1;