Genarrative/apps/ai-game-creator-shell/scripts/runner-physics.test.mjs

import assert from 'node:assert/strict';
import fs from 'node:fs';
import { test } from 'node:test';

import {
  advanceRunner,
  createRunner,
  createRunnerRandom,
  measuredRunnerFairWindowMs,
  restartRunner,
  RUNNER_SEED,
  runnerProjection,
  runnerSeedFromSearch,
  setRunnerInput,
  startRunner,
  stepRunner,
} from '../src-tauri/resources/agc-skills/agc-browser-playtest/references/runner-physics.mjs';

function jump(
  settings,
  holdTicks,
  functions = {
    createRunner,
    startRunner,
    setRunnerInput,
    stepRunner,
    runnerProjection,
  },
) {
  const state = functions.createRunner(RUNNER_SEED, settings);
  functions.startRunner(state);
  functions.setRunnerInput(state, 'jump', true);
  const samples = [];
  for (let tick = 0; tick < 150; tick += 1) {
    if (tick === holdTicks) functions.setRunnerInput(state, 'jump', false);
    functions.stepRunner(state);
    samples.push(functions.runnerProjection(state));
    if (state.onGround && state.jumpCount > 0) break;
  }
  return {
    state,
    samples,
    height: Math.max(
      ...samples.map((sample) => sample.groundY - sample.playerY),
    ),
  };
}

test('fixed seed, fixed steps and independent decoration produce the same course', () => {
  assert.equal(runnerSeedFromSearch('?agcPlaytestSeed=20260920'), RUNNER_SEED);
  assert.throws(() =>
    runnerSeedFromSearch('?agcPlaytestSeed=1&agcPlaytestSeed=2'),
  );
  assert.throws(() => runnerSeedFromSearch('?agcPlaytestSeed=4294967296'));
  const first = createRunner();
  const decoration = createRunnerRandom(71);
  for (let index = 0; index < 100; index += 1) decoration();
  const second = createRunner();
  assert.deepEqual(first.course, second.course);
  assert.notEqual(
    first.courseFingerprint,
    createRunner(20260921).courseFingerprint,
  );
  startRunner(first);
  startRunner(second);
  for (let index = 0; index < 60; index += 1) advanceRunner(first, 1 / 60);
  for (let index = 0; index < 120; index += 1) advanceRunner(second, 1 / 120);
  assert.deepEqual(runnerProjection(first), runnerProjection(second));
  const course = structuredClone(first.course);
  restartRunner(first);
  assert.equal(first.phase, 'ready');
  assert.equal(first.simulationTick, 0);
  assert.equal(first.jumpCount, 0);
  assert.deepEqual(first.course, course);
});

test('short jump cuts once, long jump rises higher, release restores slide collision size', () => {
  const short = jump({}, 4);
  const long = jump({}, 18);
  assert.equal(short.state.jumpCount, 1);
  assert.equal(short.state.jumpCutCount, 1);
  assert.ok(long.height > short.height + 10);
  assert.ok(short.state.onGround && long.state.onGround);
  const state = short.state;
  setRunnerInput(state, 'slide', true);
  stepRunner(state);
  assert.ok(state.sliding && state.playerHeight < state.config.playerHeight);
  setRunnerInput(state, 'slide', false);
  stepRunner(state);
  assert.ok(!state.sliding && !state.slideHeld);
  assert.equal(state.playerHeight, state.config.playerHeight);
});

test('baseline has at least 180ms clearance while the original narrow-window parameters fail', () => {
  const baseline = jump({}, 4);
  assert.ok(
    measuredRunnerFairWindowMs(
      baseline.samples,
      49,
      baseline.state.course[0],
    ) >= 180,
  );
  const original = jump(
    {
      gravity: 2300,
      jumpVelocity: 800,
      releaseVelocity: 720,
      playerWidth: 48.9,
    },
    1,
  );
  const window = measuredRunnerFairWindowMs(
    original.samples,
    48.9,
    original.state.course[0],
  );
  assert.ok(window < 180, `original jump window ${window}ms must fail`);
});

test('regression mutations expose repeated jump-cut and ignored slide release', async () => {
  const source = fs.readFileSync(
    new URL(
      '../src-tauri/resources/agc-skills/agc-browser-playtest/references/runner-physics.mjs',
      import.meta.url,
    ),
    'utf8',
  );
  const repeatedCut = source.replace('&& !state.jumpCut)', ')');
  assert.notEqual(repeatedCut, source);
  const broken = await import(
    `data:text/javascript;base64,${Buffer.from(repeatedCut).toString('base64')}`
  );
  assert.ok(jump({}, 4, broken).state.jumpCutCount > 1);
  const noRelease = source.replace(
    'state.slideHeld = Boolean(held);',
    'if (held) state.slideHeld = true;',
  );
  const stuck = await import(
    `data:text/javascript;base64,${Buffer.from(noRelease).toString('base64')}`
  );
  const state = stuck.createRunner();
  stuck.startRunner(state);
  stuck.setRunnerInput(state, 'slide', true);
  stuck.stepRunner(state);
  stuck.setRunnerInput(state, 'slide', false);
  stuck.stepRunner(state);
  assert.equal(state.sliding, true);
});