import assert from 'node:assert/strict';
import { spawn } from 'node:child_process';
import { createServer } from 'vite';
import { mkdtemp, rm } from 'node:fs/promises';
import { existsSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { resolve } from 'node:path';
import { fileURLToPath } from 'node:url';

const root = resolve(fileURLToPath(new URL('..', import.meta.url)));
const width = Number(process.env.GEOMETRY_WIDTH || 1200);
const height = Number(process.env.GEOMETRY_HEIGHT || 900);
const scrollAway = process.env.SCROLL_AWAY === '1';
const browser = process.env.CHROME_EXECUTABLE || [
  '/usr/bin/chromium', '/usr/bin/google-chrome', '/usr/bin/chromium-browser',
].find(existsSync) || 'chromium';
const profile = await mkdtemp(`${tmpdir()}/sybil-agent-send-geometry-`);
const server = await createServer({ configFile: resolve(root, 'vite.config.ts'), root,
  logLevel: 'error', server: { host: '127.0.0.1', port: 0, strictPort: false } });
let child;
let socket;

try {
  await server.listen();
  const address = server.httpServer.address();
  assert.ok(address && typeof address === 'object');
  const debugPort = await new Promise((resolvePort, reject) => {
    const probe = spawn(browser, ['--headless', '--no-sandbox', '--disable-dev-shm-usage', '--disable-gpu', '--window-size=1200,900',
      '--remote-debugging-port=0', '--remote-allow-origins=*', `--user-data-dir=${profile}`, '--no-first-run']);
    child = probe;
    let diagnostics = '';
    const timeout = setTimeout(() => reject(new Error(`Chrome startup failed: ${diagnostics.slice(-600)}`)), 10000);
    probe.stderr.setEncoding('utf8').on('data', chunk => {
      diagnostics += chunk;
      const match = diagnostics.match(/DevTools listening on ws:\/\/127\.0\.0\.1:(\d+)\//);
      if (match) { clearTimeout(timeout); resolvePort(Number(match[1])); }
    });
    probe.once('error', error => { clearTimeout(timeout); reject(error); });
    probe.once('close', code => { clearTimeout(timeout); reject(new Error(`Chrome exited (${code}): ${diagnostics.slice(-600)}`)); });
  });
  const targetResponse = await fetch(`http://127.0.0.1:${debugPort}/json/new?http://127.0.0.1:${address.port}/tests/agent-scroll-fixture.html`, { method: 'PUT' });
  assert.equal(targetResponse.status, 200);
  const target = await targetResponse.json();
  socket = new WebSocket(target.webSocketDebuggerUrl);
  await new Promise((resolveOpen, reject) => {
    socket.addEventListener('open', resolveOpen, { once: true });
    socket.addEventListener('error', reject, { once: true });
  });
  let commandId = 0;
  const pending = new Map();
  socket.addEventListener('message', event => {
    const message = JSON.parse(event.data);
    if (!message.id) return;
    const request = pending.get(message.id);
    if (!request) return;
    pending.delete(message.id);
    if (message.error) request.reject(new Error(`${request.method}: ${message.error.message}`));
    else request.resolve(message.result);
  });
  const call = (method, params = {}) => new Promise((resolveCall, reject) => {
    const id = ++commandId;
    pending.set(id, { resolve: resolveCall, reject, method });
    socket.send(JSON.stringify({ id, method, params }));
  });
  await call('Page.enable');
  await call('Runtime.enable');
  await call('Emulation.setDeviceMetricsOverride', { width, height, deviceScaleFactor: 1, mobile: width < 768 });
  await call('Page.navigate', { url: `http://127.0.0.1:${address.port}/tests/agent-scroll-fixture.html?scrollAway=${scrollAway ? '1' : '0'}` });
  const evaluated = await call('Runtime.evaluate', {
    expression: `new Promise(resolve => { const deadline = Date.now() + 12000; const check = () => { if (document.documentElement.dataset.fixtureComplete === 'true') resolve({ result: JSON.parse(document.getElementById('result').textContent) }); else if (Date.now() >= deadline) resolve({ timedOut: true, error: document.documentElement.dataset.fixtureError || null, hasTimeline: Boolean(document.querySelector('.agent-room__timeline')), textAreaCount: document.querySelectorAll('textarea').length, roomSendCalled: document.documentElement.dataset.roomSendCalled || false, agentSubmitCalled: document.documentElement.dataset.agentSubmitCalled || false, entries: Array.from(document.querySelectorAll('[data-agent-entry-id]')).filter(entry => entry.dataset.agentEntryId.includes('fixture')).map(entry => ({ id: entry.dataset.agentEntryId, captured: entry.dataset.geometryCaptured || false, animations: entry.getAnimations().map(animation => ({ state: animation.playState, time: animation.currentTime, target: animation.effect?.target?.className || 'other' })) })), reducedMotion: matchMedia('(prefers-reduced-motion: reduce)').matches, resultText: document.getElementById('result')?.textContent }); else setTimeout(check, 25); }; check(); })`,
    awaitPromise: true,
    returnByValue: true,
  });
  assert.equal(evaluated.exceptionDetails, undefined, evaluated.exceptionDetails?.text);
  const page = evaluated.result.value;
  assert.equal(page.timedOut, undefined, `fixture timed out: ${JSON.stringify(page)}`);
  const result = page.result;
  if (process.env.BASELINE_GEOMETRY !== '1') {
    const byLabel = Object.fromEntries(result.samples.map(sample => [sample.label, sample]));
    for (const label of ['user', 'agent']) {
      assert.ok(byLabel[`${label}-start`] && byLabel[`${label}-mid`] && byLabel[`${label}-late`] && byLabel[`${label}-pre-end`] && byLabel[`${label}-finish`] && byLabel[`${label}-stable`], JSON.stringify(result.samples));
      const endpoint = Number(String(byLabel[`${label}-start`].keyframeHeights[1]).replace('px', ''));
      assert.ok(endpoint + 1 >= byLabel[`${label}-start`].contentHeight,
        `${label} animation used a culling placeholder instead of its content height: ${JSON.stringify(result.samples)}`);
      assert.equal(byLabel[`${label}-mid`].entryAnimationCount, 1, `${label} entrance animation stopped before the intermediate sample`);
      assert.ok(Math.abs(byLabel[`${label}-finish`].rowHeight - byLabel[`${label}-stable`].rowHeight) < 1,
        `${label} height moved after animation finish: ${JSON.stringify(result.samples)}`);
      assert.ok(byLabel[`${label}-stable`].entryAnimationCount === 0, `${label} entry animation did not clean up`);
      assert.ok(byLabel[`${label}-finish`].time - byLabel[`${label}-start`].time < 330,
        `${label} entrance animation was prolonged by streaming updates: ${JSON.stringify(result.samples)}`);
      if (scrollAway) {
        assert.ok(Math.abs(Number(byLabel[`${label}-stable`].anchorShift)) < 1, `${label} reader anchor moved: ${JSON.stringify(result.samples)}`);
        assert.ok(byLabel[`${label}-stable`].bottomGap > 100, `${label} reader was pulled to bottom: ${JSON.stringify(result.samples)}`);
      } else assert.ok(byLabel[`${label}-stable`].bottomGap <= 1, `${label} pinned viewport left a gap: ${JSON.stringify(result.samples)}`);
    }
    assert.ok(byLabel['agent-late'].emptyHeight < 40, `Agent spacer persisted late in the entrance animation: ${JSON.stringify(result.samples)}`);
    const retargetedEndpoint = Number(String(byLabel['agent-mid'].keyframeHeights.at(-1)).replace('px', ''));
    assert.ok(byLabel['agent-mid'].keyframeHeights.length >= 3 && Math.abs(retargetedEndpoint - byLabel['agent-mid'].contentHeight) < 1,
      `Agent animation did not retarget to the streamed message height: ${JSON.stringify(result.samples)}`);
    assert.ok(Math.abs(byLabel['agent-pre-end'].emptyHeight) < 2, `Agent row changed height as the entrance animation finished: ${JSON.stringify(result.samples)}`);
    assert.ok(Math.abs(byLabel['agent-stable'].emptyHeight) < 1, `Agent reply left an empty spacer: ${JSON.stringify(result.samples)}`);
    assert.equal(result.roomSendCalled, true, 'composer did not use the real room send boundary');
    assert.equal(result.agentSubmitCalled, true, 'optimistic outbox did not invoke its submission boundary');
    assert.equal(result.composerFocused, true, 'composer focus was lost after send');
    assert.equal(result.readDuringEntryAnimation, false, 'read state advanced during an entry animation');
    assert.equal(byLabel['user-stable'].emptyHeight, 0, 'sent user message retained an empty spacer');
  }
  process.stdout.write(`${JSON.stringify({ browser, width, height, scrollAway, baseline: process.env.BASELINE_GEOMETRY === '1', result }, null, 2)}\n`);
} finally {
  socket?.close();
  if (child && child.exitCode === null) {
    const closed = new Promise(resolveClose => child.once('close', resolveClose));
    child.kill('SIGTERM');
    await closed;
  }
  await server.close();
  await rm(profile, { recursive: true, force: true });
}