#!/usr/bin/env node
/**
 * Headless end-to-end smoke test driven over the Chrome DevTools Protocol.
 * Usage: PATH=/opt/node22/bin:$PATH node tools/e2e.mjs <projectId> [baseUrl]
 * Writes screenshots to /tmp/gm-e2e-*.png and prints PASS/FAIL checks. No dependencies.
 *
 * Widgets are located through `window.__gm.locate(text)` (installed by the editor), so
 * the test does not depend on pixel coordinates.
 */
import { spawn } from 'node:child_process';
import { writeFileSync } from 'node:fs';

const projectId = process.argv[2];
const baseUrl = process.argv[3] ?? 'https://nockal.com/game-maker/';
if (!projectId) {
  console.error('usage: node tools/e2e.mjs <projectId> [baseUrl]');
  process.exit(2);
}
const PORT = 9333;
const W = 1280;
const H = 800;

const chrome = spawn('chromium', [
  '--headless', '--no-sandbox', '--disable-gpu', '--use-gl=swiftshader', '--enable-unsafe-swiftshader',
  `--remote-debugging-port=${PORT}`, `--window-size=${W},${H}`, '--hide-scrollbars', 'about:blank',
], { stdio: 'ignore' });

const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

async function waitForChrome() {
  for (let i = 0; i < 50; i++) {
    try {
      const res = await fetch(`http://127.0.0.1:${PORT}/json/version`);
      if (res.ok) return res.json();
    } catch {}
    await sleep(200);
  }
  throw new Error('chromium did not start');
}

class CDP {
  constructor(ws) {
    this.ws = ws;
    this.id = 0;
    this.pending = new Map();
    this.listeners = [];
    ws.addEventListener('message', (ev) => {
      const msg = JSON.parse(ev.data);
      if (msg.id && this.pending.has(msg.id)) {
        const { resolve, reject } = this.pending.get(msg.id);
        this.pending.delete(msg.id);
        msg.error ? reject(new Error(msg.error.message)) : resolve(msg.result);
      } else if (msg.method) {
        for (const l of this.listeners) l(msg);
      }
    });
  }
  send(method, params = {}) {
    const id = ++this.id;
    this.ws.send(JSON.stringify({ id, method, params }));
    return new Promise((resolve, reject) => this.pending.set(id, { resolve, reject }));
  }
  on(fn) { this.listeners.push(fn); }
}

const consoleLog = [];
let failures = 0;
function check(name, ok, detail = '') {
  console.log(`${ok ? 'PASS' : 'FAIL'}  ${name}${detail ? ' – ' + detail : ''}`);
  if (!ok) failures++;
}

try {
  await waitForChrome();
  const target = await (await fetch(`http://127.0.0.1:${PORT}/json/new?about:blank`, { method: 'PUT' })).json();
  const ws = new WebSocket(target.webSocketDebuggerUrl);
  await new Promise((r) => ws.addEventListener('open', r));
  const cdp = new CDP(ws);
  await cdp.send('Page.enable');
  await cdp.send('Runtime.enable');
  await cdp.send('Emulation.setDeviceMetricsOverride', { width: W, height: H, deviceScaleFactor: 1, mobile: false });
  cdp.on((msg) => {
    if (msg.method === 'Runtime.consoleAPICalled') consoleLog.push(msg.params.args.map((a) => a.value ?? a.description).join(' '));
    if (msg.method === 'Runtime.exceptionThrown') consoleLog.push('EXCEPTION ' + (msg.params.exceptionDetails.exception?.description ?? msg.params.exceptionDetails.text));
  });

  const evaluate = async (expression) => (await cdp.send('Runtime.evaluate', { expression, awaitPromise: true, returnByValue: true })).result.value;
  const locate = async (text) => {
    const p = await evaluate(`window.__gm && window.__gm.locate(${JSON.stringify(text)})`);
    if (!p) throw new Error(`widget with text "${text}" not found`);
    return p;
  };
  const shot = async (name) => {
    const { data } = await cdp.send('Page.captureScreenshot', { format: 'png' });
    writeFileSync(`/tmp/gm-e2e-${name}.png`, Buffer.from(data, 'base64'));
  };
  const mouse = (type, x, y, button = 'left', extra = {}) =>
    cdp.send('Input.dispatchMouseEvent', { type, x, y, button, clickCount: type === 'mousePressed' || type === 'mouseReleased' ? 1 : 0, ...extra });
  const click = async (x, y, button = 'left') => {
    await mouse('mouseMoved', x, y);
    await mouse('mousePressed', x, y, button);
    await mouse('mouseReleased', x, y, button);
    await sleep(150);
  };
  const clickText = async (text, button = 'left') => {
    const p = await locate(text);
    await click(p.x, p.y, button);
  };
  const drag = async (x1, y1, x2, y2, steps = 12) => {
    await mouse('mouseMoved', x1, y1);
    await mouse('mousePressed', x1, y1);
    for (let i = 1; i <= steps; i++) {
      await mouse('mouseMoved', x1 + ((x2 - x1) * i) / steps, y1 + ((y2 - y1) * i) / steps, 'left', { buttons: 1 });
      await sleep(16);
    }
    await mouse('mouseReleased', x2, y2);
    await sleep(150);
  };
  const keyPress = async (key, code, opts = {}) => {
    await cdp.send('Input.dispatchKeyEvent', { type: 'keyDown', key, code, ...opts });
    await cdp.send('Input.dispatchKeyEvent', { type: 'keyUp', key, code, ...opts });
  };
  const typeText = async (text) => {
    for (const ch of text) await cdp.send('Input.insertText', { text: ch });
  };
  const api = async (route) => (await fetch(`${baseUrl}api/index.php?r=${route}`)).json();
  const sceneOf = (doc) => doc.project.assets.find((a) => a.type === 'scene');
  const stateJson = () => evaluate('JSON.stringify({ selection: __gm.state.selection, mode: __gm.state.mode, save: __gm.state.saveStatus, notice: __gm.state.notice })');

  await cdp.send('Page.navigate', { url: `${baseUrl}?project=${projectId}` });
  await sleep(4000);
  await shot('01-loaded');
  check('page loaded without exceptions', !consoleLog.some((l) => l.startsWith('EXCEPTION')), consoleLog.filter((l) => l.startsWith('EXCEPTION')).join(' | '));
  check('debug hook present', Boolean(await evaluate('Boolean(window.__gm)')));

  // 1. Select the blue crate in the hierarchy.
  await clickText('Blue crate');
  let s = JSON.parse(await stateJson());
  check('hierarchy click selects object', s.selection?.kind === 'object' && s.selection.objectId === 'o2', JSON.stringify(s.selection));
  await shot('02-object-selected');

  // 2. Rename via inspector: the name field sits right of the "Name" label.
  const nameLabel = await locate('Name');
  await click(nameLabel.x + 160, nameLabel.y);
  await keyPress('a', 'KeyA', { modifiers: 2, windowsVirtualKeyCode: 65 }); // Ctrl+A in the bridge input
  await typeText('Renamed crate');
  await shot('03-typing');
  await keyPress('Enter', 'Enter', { windowsVirtualKeyCode: 13 });
  await sleep(200);
  s = JSON.parse(await stateJson());
  const nameNow = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').name`);
  check('typing + Enter renamed the object', nameNow === 'Renamed crate', JSON.stringify(nameNow));
  await shot('04-renamed');

  // 3. Scrub the X field (right of the "X" label) by 100 px.
  const xLabel = await locate('X');
  await drag(xLabel.x + 160, xLabel.y, xLabel.x + 260, xLabel.y);
  const xNow = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x`);
  check('scrubbing X moved the object', xNow > 120, `x=${xNow}`);
  await shot('05-scrubbed');

  // 3b. Type into X, then click straight into the empty viewport: the typed value must be
  //     committed (not reverted) even though the click deselects and rebuilds the inspector.
  const center = await evaluate('__gm.viewportCenter()');
  await click(xLabel.x + 160, xLabel.y); // plain click → text editing with everything selected
  await typeText('300');
  await click(center.x, center.y + 250);
  const xTyped = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x`);
  s = JSON.parse(await stateJson());
  check('typed X survives clicking into the viewport', xTyped === 300 && s.selection === null, `x=${xTyped} selection=${JSON.stringify(s.selection)}`);

  // 4. Drag the red crate in the viewport. It is at world (-150,0); the view is centred
  //    on the origin, so compute its screen position from the viewport widget bounds.
  await drag(center.x - 150, center.y, center.x - 50, center.y - 70);
  const o1Now = await evaluate(`JSON.stringify(__gm.state.activeScene.objects.find(o => o.id === 'o1').position)`);
  check('viewport drag moved the red crate', JSON.parse(o1Now).x > -150, o1Now);
  await shot('06-dragged');

  // 5. Autosave → server.
  await sleep(1800);
  const saved = await api(`projects/${projectId}`);
  const renamed = sceneOf(saved).objects.find((o) => o.id === 'o2');
  check('rename persisted', renamed.name === 'Renamed crate', renamed.name);
  check('scrub persisted', renamed.position.x > 120, JSON.stringify(renamed.position));
  check('override kept', renamed.overrides.color === 4491519, JSON.stringify(renamed.overrides));
  check('save status is saved', (JSON.parse(await stateJson())).save === 'saved');

  // 6. Undo four times (drag, typed X, scrub, rename) with Ctrl+Z, then redo once.
  await click(center.x, center.y + 200); // click empty viewport → deselect, drop focus
  for (let i = 0; i < 4; i++) {
    await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
    await sleep(80);
  }
  const afterUndo = JSON.parse(await evaluate(`JSON.stringify(__gm.state.activeScene.objects.map(o => ({ id: o.id, name: o.name, x: o.position.x })))`));
  check('undo reverted drag, typed X, scrub and rename', afterUndo[0].x === -150 && afterUndo[1].x === 120 && afterUndo[1].name === 'Blue crate', JSON.stringify(afterUndo));
  await keyPress('z', 'KeyZ', { modifiers: 10, windowsVirtualKeyCode: 90 }); // Ctrl+Shift+Z
  const afterRedo = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').name`);
  check('redo restored the rename', afterRedo === 'Renamed crate', afterRedo);
  await shot('07-undo-redo');

  // 7. Play: the camera frame is rendered (both crates lie inside the 640×360 frame at the
  //    origin; the behavior symbol is editor-only). The "Mover" behavior owns the red crate:
  //    holding ArrowRight moves it in the world (Axis input × speed × dt), Esc stops without
  //    touching the model.
  await clickText('Renamed crate');
  const xBeforePlay = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x`);
  await clickText('▶  Play');
  await sleep(300);
  s = JSON.parse(await stateJson());
  check('play mode entered', s.mode === 'play', JSON.stringify(s));
  let info = await evaluate('JSON.stringify(__gm.viewportInfo())');
  check('play renders the camera frame with both crates', JSON.parse(info).rendering && JSON.parse(info).visibleItems === 2, info);
  await shot('08-playing');
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
  await sleep(400);
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
  const worldAfterRight = JSON.parse(await evaluate('JSON.stringify(__gm.world())'));
  const movedCrate = worldAfterRight.entities.find((e) => e.objectId === 'o1');
  check('behavior graph moved its owner while ArrowRight was held', movedCrate.x > -150 + 30, `world x=${movedCrate.x}`);
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
  await sleep(250);
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
  const afterLeft = JSON.parse(await evaluate('JSON.stringify(__gm.world())')).entities.find((e) => e.objectId === 'o1');
  check('ArrowLeft (axis x = −1) moved the owner back left', afterLeft.x < movedCrate.x, `world x=${afterLeft.x}`);
  await keyPress('Escape', 'Escape', { windowsVirtualKeyCode: 27 });
  await sleep(300);
  s = JSON.parse(await stateJson());
  check('escape stopped play', s.mode === 'edit', JSON.stringify(s));
  await shot('09-stopped');
  const o2AfterPlay = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x`);
  const o1AfterPlay = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o1').position.x`);
  check('play did not write back to the model', o2AfterPlay === xBeforePlay && o1AfterPlay === -150, `${o2AfterPlay} vs ${xBeforePlay}, o1=${o1AfterPlay}`);

  // 7b. Culling: move the blue crate far outside the camera frame → only one item visible.
  await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x = 5000; __gm.state.preview()`);
  await clickText('▶  Play');
  await sleep(300);
  info = await evaluate('JSON.stringify(__gm.viewportInfo())');
  check('objects outside the camera frame are culled', JSON.parse(info).visibleItems === 1, info);
  await keyPress('Escape', 'Escape', { windowsVirtualKeyCode: 27 });
  await sleep(200);
  await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o2').position.x = ${xBeforePlay}; __gm.state.preview()`);

  // 7c. Without a camera nothing is rendered: delete the camera object, play, then undo.
  await evaluate(`__gm.state.select({ kind: 'object', sceneId: 'scene1', objectId: 'o3' })`);
  await keyPress('Delete', 'Delete', { windowsVirtualKeyCode: 46 });
  await sleep(200);
  check('camera object deleted', (await evaluate('__gm.state.activeScene.objects.length')) === 3);
  await clickText('▶  Play');
  await sleep(300);
  info = await evaluate('JSON.stringify(__gm.viewportInfo())');
  s = JSON.parse(await stateJson());
  check('play without camera renders nothing', s.mode === 'play' && !JSON.parse(info).rendering && JSON.parse(info).visibleItems === 0, info);
  check('play without camera shows a notice', s.notice.includes('no camera'), s.notice);
  await shot('10-play-no-camera');
  await keyPress('Escape', 'Escape', { windowsVirtualKeyCode: 27 });
  await sleep(300);
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(200);
  check('undo restored the camera object', (await evaluate('__gm.state.activeScene.objects.length')) === 4);

  // 8. Context menu on the Crate asset → menu shows "Place in scene".
  await clickText('Crate', 'right');
  await sleep(200);
  const menuVisible = await evaluate(`Boolean(__gm.locate('Place in scene'))`);
  check('asset context menu opens', menuVisible);
  await shot('11-context-menu');
  await clickText('Place in scene');
  await sleep(200);
  const count = await evaluate('__gm.state.activeScene.objects.length');
  check('placing from the menu adds an object', count === 5, `objects=${count}`);

  // 9. Create a new asset through the + menu.
  await clickText('+');
  await sleep(150);
  await clickText('Sprite');
  await sleep(200);
  const assets = await evaluate(`JSON.stringify(__gm.state.project.assets.map(a => a.name))`);
  check('+ menu creates a sprite asset', JSON.parse(assets).includes('Sprite'), assets);
  await shot('12-new-asset');

  // 10. Symbols stay on top: put the camera first in the hierarchy (drawn first) and a crate
  //     right on top of its icon → the icon must still be drawn above the sprite.
  await evaluate(`(() => {
    const objs = __gm.state.activeScene.objects;
    const cam = objs.splice(objs.findIndex(o => o.id === 'o3'), 1)[0];
    objs.unshift(cam);
    const crate = objs.find(o => o.id === 'o1');
    crate.position.x = 0; crate.position.y = 0;
    __gm.state.select(null);
    __gm.state.preview();
  })()`);
  await sleep(200);
  const layers = await evaluate(`JSON.stringify([__gm.layerOf('o3'), __gm.layerOf('o1'), __gm.layerOf('o2')])`);
  check('camera symbol is drawn in the overlay layer above sprites', layers === '["overlay","objects","objects"]', layers);
  await shot('13-symbol-on-top');

  // 11. Z-order: put both crates on the origin. With equal z the hierarchy order wins
  //     (o1 before o2 → o2 on top); raising o1's z draws it above o2; undo restores it.
  await evaluate(`(() => {
    const o2 = __gm.state.activeScene.objects.find(o => o.id === 'o2');
    o2.position.x = 0; o2.position.y = 0;
    __gm.state.preview();
  })()`);
  await sleep(200);
  const orderBefore = await evaluate(`JSON.stringify(__gm.drawOrder().filter(id => id === 'o1' || id === 'o2'))`);
  check('equal z keeps hierarchy order', orderBefore === '["o1","o2"]', orderBefore);
  await evaluate(`__gm.state.select({ kind: 'object', sceneId: __gm.state.activeScene.id, objectId: 'o1' })`);
  await sleep(200);
  const zLabel = await locate('Z');
  await click(zLabel.x + 160, zLabel.y); // plain click → text editing with everything selected
  await typeText('5');
  await keyPress('Enter', 'Enter', { windowsVirtualKeyCode: 13 });
  await sleep(200);
  const zNow = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o1').position.z`);
  check('Z field sets position.z', zNow === 5, `z=${zNow}`);
  const orderAfter = await evaluate(`JSON.stringify(__gm.drawOrder().filter(id => id === 'o1' || id === 'o2'))`);
  check('higher z is drawn on top', orderAfter === '["o2","o1"]', orderAfter);
  await shot('14-z-order');
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(200);
  const zUndone = await evaluate(`__gm.state.activeScene.objects.find(o => o.id === 'o1').position.z`);
  check('undo restores z', zUndone === 0, `z=${zUndone}`);

  // 12. Asset defaults: the Crate asset has height 60 (schema default 100), width and
  //     color at their defaults → exactly one reset button is visible. Clicking it puts
  //     height back to 100 and hides the button; undo brings 60 back.
  await evaluate(`__gm.state.select({ kind: 'asset', assetId: 'crate' })`);
  await sleep(200);
  const resetButton = await evaluate(`__gm.locate('↺')`);
  check('asset inspector shows a reset for the non-default height', Boolean(resetButton));
  await click(resetButton.x, resetButton.y);
  await sleep(200);
  const heightReset = await evaluate(`__gm.state.project.assets.find(a => a.id === 'crate').props.height`);
  check('reset puts the asset property back to its default', heightReset === 100, `height=${heightReset}`);
  check('reset button hidden once the value is at default', !(await evaluate(`__gm.locate('↺')`)));
  await shot('15-asset-reset');
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(200);
  const heightUndone = await evaluate(`__gm.state.project.assets.find(a => a.id === 'crate').props.height`);
  check('undo restores the asset value', heightUndone === 60, `height=${heightUndone}`);
  check('reset button visible again after undo', Boolean(await evaluate(`__gm.locate('↺')`)));

  // 13. Behavior graph editor. Selecting the Mover asset binds the graph; the Graph tab shows it.
  await clickText('Mover');
  await evaluate(`__gm.showTab('graph')`);
  await sleep(250);
  check('graph editor shows the selected behavior', (await evaluate(`__gm.graph.current()`)) === 'mover' && (await evaluate('__gm.tab()')) === 'graph');
  await shot('16-graph');
  const nodeOf = (id) => evaluate(`JSON.stringify(__gm.state.project.assets.find(a => a.id === 'mover').graph.nodes.find(n => n.id === ${JSON.stringify(id)}))`).then(JSON.parse);
  const graphCounts = () => evaluate(`(() => { const g = __gm.state.project.assets.find(a => a.id === 'mover').graph; return JSON.stringify({ nodes: g.nodes.length, edges: g.edges.length }); })()`).then(JSON.parse);

  // 13a. Drag a node: clicking its title selects it, dragging moves it (undoable).
  const mulBefore = await nodeOf('n-axis');
  const mulPos = JSON.parse(await evaluate(`JSON.stringify(__gm.graph.nodeAt('n-axis'))`));
  await drag(mulPos.x, mulPos.y, mulPos.x + 60, mulPos.y + 40);
  s = JSON.parse(await stateJson());
  const mulAfter = await nodeOf('n-axis');
  check('dragging a node selects and moves it', s.selection?.kind === 'node' && s.selection.nodeId === 'n-axis' && mulAfter.x === mulBefore.x + 60 && mulAfter.y === mulBefore.y + 40, `${JSON.stringify(s.selection)} ${mulBefore.x},${mulBefore.y} → ${mulAfter.x},${mulAfter.y}`);
  check('node inspector shows the node', Boolean(await evaluate(`__gm.locate('Axis input')`)) && Boolean(await evaluate(`__gm.locate('DATA NODE')`)));
  // The Move node's unconnected `scale` shows its port default (1) once its edge is removed;
  // with the edge present the inspector hides it. Port defaults are covered by unit tests.
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(150);
  const mulUndone = await nodeOf('n-axis');
  check('undo moves the node back', mulUndone.x === mulBefore.x && mulUndone.y === mulBefore.y, `${mulUndone.x},${mulUndone.y}`);

  // 13a. Regression: typing a query and then *clicking* a row must add exactly one node.
  // (Previously the search field's blur-commit picked the first match and the row click
  // picked it again → two nodes.)
  const gcenter = JSON.parse(await evaluate(`JSON.stringify(__gm.graph.center())`));
  const beforeClickPick = await graphCounts();
  await click(gcenter.x + 250, gcenter.y + 250, 'right');
  await sleep(250);
  check('node palette opens (row-click case)', Boolean(await evaluate(`__gm.locate('Search nodes…')`)));
  await typeText('stop');
  await sleep(150);
  const stopRow = await locate('Stop game'); // unique on screen (nothing else on screen shows this label)
  await click(stopRow.x, stopRow.y);
  await sleep(250);
  const afterClickPick = await graphCounts();
  check('clicking a palette row adds exactly one node', afterClickPick.nodes === beforeClickPick.nodes + 1, JSON.stringify({ beforeClickPick, afterClickPick }));
  check('palette closed after row click', !(await evaluate(`__gm.locate('Search nodes…')`)));
  // Undo so 13b finds the same empty spot and the expected graph.
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(150);
  check('undo removes the clicked node again', (await graphCounts()).nodes === beforeClickPick.nodes);

  // 13b. Right-click the empty canvas → palette → search "log" → Enter adds a Log node.
  const before13 = await graphCounts();
  await click(gcenter.x + 250, gcenter.y + 250, 'right');
  await sleep(250);
  check('node palette opens', Boolean(await evaluate(`__gm.locate('Search nodes…')`)));
  await typeText('log');
  await sleep(100);
  await keyPress('Enter', 'Enter', { windowsVirtualKeyCode: 13 });
  await sleep(250);
  const after13 = await graphCounts();
  s = JSON.parse(await stateJson());
  const newNode = s.selection?.kind === 'node' ? await nodeOf(s.selection.nodeId) : null;
  check('palette adds a Log node and selects it', after13.nodes === before13.nodes + 1 && newNode?.type === 'Log', JSON.stringify({ after13, newNode }));
  await shot('17-node-added');

  // 13c. Connect: drag from the upper Move node's exec output onto the Log node's exec input.
  const fromPort = JSON.parse(await evaluate(`JSON.stringify(__gm.graph.portAt('n-move', 'exec', true))`));
  const toPort = JSON.parse(await evaluate(`JSON.stringify(__gm.graph.portAt(${JSON.stringify(newNode.id)}, 'exec', false))`));
  await drag(fromPort.x, fromPort.y, toPort.x, toPort.y, 16);
  const connected = await graphCounts();
  check('dragging port to port connects the nodes', connected.edges === before13.edges + 1, JSON.stringify(connected));
  // An exec output must not connect to a data input: dragging onto "message" does nothing.
  const dataPort = JSON.parse(await evaluate(`JSON.stringify(__gm.graph.portAt(${JSON.stringify(newNode.id)}, 'message', false))`));
  await drag(fromPort.x, fromPort.y, dataPort.x, dataPort.y, 16);
  check('incompatible ports are rejected', (await graphCounts()).edges === before13.edges + 1 && s.mode === 'edit');
  await shot('18-connected');

  // 13d. Delete removes the selected node together with its edge; undo brings both back.
  await evaluate(`__gm.state.select({ kind: 'node', assetId: 'mover', nodeId: ${JSON.stringify(newNode.id)} })`);
  await keyPress('Delete', 'Delete', { windowsVirtualKeyCode: 46 });
  await sleep(150);
  const deleted = await graphCounts();
  check('Delete removes the node and its edge', deleted.nodes === before13.nodes && deleted.edges === before13.edges, JSON.stringify(deleted));
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(150);
  const restored = await graphCounts();
  check('undo restores node and edge', restored.nodes === before13.nodes + 1 && restored.edges === before13.edges + 1, JSON.stringify(restored));

  // 13e. Play always starts on the Scene tab; switching back to Graph while playing shows
  // the live highlight: hold ArrowRight → the exec edge is hot.
  await clickText('▶  Play');
  await sleep(200);
  check('play switches to the scene tab', (await evaluate('__gm.tab()')) === 'scene');
  await evaluate(`__gm.showTab('graph')`);
  await sleep(100);
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
  await sleep(300);
  await shot('19-graph-live');
  await cdp.send('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
  await keyPress('Escape', 'Escape', { windowsVirtualKeyCode: 27 });
  await sleep(200);

  // 13f. Variables: "+ Variable ▾" → Number adds "var1" with default 0; undo removes it.
  await evaluate(`__gm.state.select({ kind: 'asset', assetId: 'mover' })`);
  await sleep(150);
  await clickText('+ Variable ▾');
  await sleep(150);
  await clickText('Number');
  await sleep(200);
  const vars = JSON.parse(await evaluate(`JSON.stringify(__gm.state.project.assets.find(a => a.id === 'mover').variables.map(v => v.key))`));
  check('adding a variable declares it on the behavior', vars.join(',') === 'speed,var1', vars.join(','));
  await shot('20-variable-added');
  await keyPress('z', 'KeyZ', { modifiers: 2, windowsVirtualKeyCode: 90 });
  await sleep(150);
  const varsUndone = JSON.parse(await evaluate(`JSON.stringify(__gm.state.project.assets.find(a => a.id === 'mover').variables.map(v => v.key))`));
  check('undo removes the variable', varsUndone.join(',') === 'speed', varsUndone.join(','));

  // 13g. The graph strictly mirrors the selection: nothing / a non-behavior → empty editor.
  await evaluate(`__gm.state.select(null)`);
  await sleep(100);
  check('graph editor empties when nothing is selected', (await evaluate(`__gm.graph.current()`)) === null);
  await evaluate(`__gm.state.select({ kind: 'asset', assetId: 'cam' })`);
  await sleep(100);
  check('graph editor stays empty for a non-behavior asset', (await evaluate(`__gm.graph.current()`)) === null);
  await evaluate(`__gm.state.select({ kind: 'asset', assetId: 'mover' })`);
  await sleep(100);
  check('graph editor rebinds when a behavior is selected again', (await evaluate(`__gm.graph.current()`)) === 'mover');
  await evaluate(`__gm.showTab('scene')`);

  check('no exceptions during run', !consoleLog.some((l) => l.startsWith('EXCEPTION')), consoleLog.filter((l) => l.startsWith('EXCEPTION')).slice(0, 3).join(' | '));
  ws.close();
} catch (error) {
  console.error(error);
  failures++;
} finally {
  // Wait for chromium to actually exit (a SwiftShader GPU process kept rendering at full CPU
  // once when only SIGTERM was sent); escalate to SIGKILL if it does not stop in time.
  await new Promise((resolve) => {
    if (chrome.exitCode !== null) return resolve();
    const timer = setTimeout(() => { chrome.kill('SIGKILL'); }, 5000);
    chrome.once('exit', () => { clearTimeout(timer); resolve(); });
    chrome.kill('SIGTERM');
  });
}
if (consoleLog.length) console.log('--- console ---\n' + consoleLog.slice(0, 20).join('\n'));
process.exit(failures ? 1 : 0);