import { spawn } from 'node:child_process';
import { chromium } from 'playwright';

const targetUrl = process.env.VERIFY_URL ?? 'http://localhost:5173/';

let serverProcess;
let browser;

try {
  serverProcess = await ensureLocalServer(targetUrl);

  browser = await chromium.launch({ headless: true });
  const page = await browser.newPage({ viewport: { width: 1280, height: 720 } });

  await page.goto(targetUrl, { waitUntil: 'networkidle' });
  await page.waitForSelector('canvas');
  await page.waitForFunction(() => window.__HEROS_GAME__ !== undefined);
  await page.waitForFunction(() => window.__HEROS_DEBUG__ !== undefined);
  await page.waitForTimeout(500);

  const debugBeforeBattle = await page.evaluate(() => window.__HEROS_DEBUG__?.activeScenes() ?? []);
  if (!debugBeforeBattle.includes('TitleScene')) {
    throw new Error(`Expected TitleScene before starting. Active scenes: ${debugBeforeBattle.join(', ')}`);
  }

  await page.mouse.click(962, 240);
  await page.waitForTimeout(250);

  for (let i = 0; i < 20; i += 1) {
    const isBattleActive = await page.evaluate(() => {
      const activeScenes = window.__HEROS_GAME__?.scene.getScenes(true) ?? [];
      return activeScenes.some((scene) => scene.scene.key === 'BattleScene');
    });

    if (isBattleActive) {
      break;
    }

    await page.keyboard.press('Space');
    await page.waitForTimeout(220);
  }

  await page.waitForFunction(() => {
    const activeScenes = window.__HEROS_GAME__?.scene.getScenes(true) ?? [];
    return activeScenes.some((scene) => scene.scene.key === 'BattleScene');
  });

  await page.keyboard.press('F9');
  await page.waitForTimeout(100);
  await page.screenshot({ path: 'dist/verification-battle.png', fullPage: true });

  const result = await page.evaluate(() => {
    const canvas = document.querySelector('canvas');
    const activeScenes = window.__HEROS_DEBUG__?.activeScenes() ?? [];
    const battleState = window.__HEROS_DEBUG__?.battle();

    return {
      activeScenes,
      battleState,
      canvasWidth: canvas?.width ?? 0,
      canvasHeight: canvas?.height ?? 0
    };
  });

  if (result.canvasWidth !== 1280 || result.canvasHeight !== 720) {
    throw new Error(`Unexpected canvas size: ${result.canvasWidth}x${result.canvasHeight}`);
  }

  if (!result.activeScenes.includes('BattleScene')) {
    throw new Error(`BattleScene was not active. Active scenes: ${result.activeScenes.join(', ')}`);
  }

  if (!result.battleState || result.battleState.scene !== 'BattleScene') {
    throw new Error(`Debug battle state was not available: ${JSON.stringify(result.battleState)}`);
  }

  console.log(`Verified title-to-battle flow and debug API at ${targetUrl}`);
} finally {
  await browser?.close();
  if (serverProcess && !serverProcess.killed) {
    serverProcess.kill();
  }
}

async function ensureLocalServer(url) {
  if (await canReach(url)) {
    return undefined;
  }

  const parsed = new URL(url);
  const isLocal = ['localhost', '127.0.0.1', '0.0.0.0'].includes(parsed.hostname);
  if (!isLocal) {
    throw new Error(`No server responded at ${url}`);
  }

  const stderr = [];
  const child = spawn(process.execPath, ['node_modules/vite/bin/vite.js', '--host', '127.0.0.1', '--port', parsed.port || '5173'], {
    cwd: process.cwd(),
    env: process.env,
    stdio: ['ignore', 'pipe', 'pipe']
  });

  child.stderr.on('data', (chunk) => stderr.push(chunk.toString()));
  child.stdout.on('data', () => {});

  for (let i = 0; i < 80; i += 1) {
    if (await canReach(url)) {
      return child;
    }
    await delay(250);
  }

  child.kill();
  throw new Error(`Vite server did not start at ${url}\n${stderr.join('')}`);
}

async function canReach(url) {
  try {
    const response = await fetch(url, { signal: AbortSignal.timeout(1000) });
    return response.ok;
  } catch {
    return false;
  }
}

function delay(ms) {
  return new Promise((resolve) => setTimeout(resolve, ms));
}