import { test } from 'node:test';
import assert from 'node:assert/strict';
import { join } from 'node:path';
import { mkdirSync, writeFileSync, readFileSync, existsSync, rmSync, mkdtempSync, symlinkSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { platform } from 'node:process';
import { deflateSync } from 'node:zlib';
import { buildGame } from '../build-game.mjs';

const LINK_TYPE = platform === 'win32' ? 'junction' : 'dir';

function crc32(buf) {
  let c = ~0;
  for (const x of buf) { c ^= x; for (let i = 0; i < 8; i++) c = (c >>> 1) ^ (0xEDB88320 & -(c & 1)); }
  return ~c >>> 0;
}
function chunk(type, data) {
  const len = Buffer.alloc(4); len.writeUInt32BE(data.length);
  const td = Buffer.concat([Buffer.from(type, 'ascii'), data]);
  const c = Buffer.alloc(4); c.writeUInt32BE(crc32(td));
  return Buffer.concat([len, td, c]);
}
function makePng(w, h, rgb = [0, 0, 0]) {
  const ihdr = Buffer.alloc(13);
  ihdr.writeUInt32BE(w, 0); ihdr.writeUInt32BE(h, 4); ihdr[8] = 8; ihdr[9] = 2;
  const raw = Buffer.alloc(h * (1 + w * 3));
  for (let y = 0; y < h; y++) {
    const off = y * (1 + w * 3);
    raw[off] = 0;
    for (let x = 0; x < w; x++) {
      raw[off + 1 + x * 3] = rgb[0]; raw[off + 2 + x * 3] = rgb[1]; raw[off + 3 + x * 3] = rgb[2];
    }
  }
  return Buffer.concat([
    Buffer.from([137, 80, 78, 71, 13, 10, 26, 10]),
    chunk('IHDR', ihdr), chunk('IDAT', deflateSync(raw)), chunk('IEND', Buffer.alloc(0)),
  ]);
}

const DEFAULT_BTN = makePng(64, 64, [1, 2, 3]);
const SKINNED = makePng(64, 64, [9, 9, 9]);

function put(dir, rel, content) {
  const p = join(dir, ...rel.split('/'));
  mkdirSync(join(p, '..'), { recursive: true });
  writeFileSync(p, content);
}

function scaffold(gameVersion = '3.8.8') {
  const root = mkdtempSync(join(tmpdir(), 'youle-build-'));
  const hostProject = join(root, 'nexus');
  const frameworkSrc = join(hostProject, 'assets', 'framework');
  mkdirSync(frameworkSrc, { recursive: true });
  writeFileSync(join(hostProject, 'package.json'), JSON.stringify({ name: 'YouleNexus', creator: { version: '3.8.8' } }));
  put(frameworkSrc, 'ui/atlas-hall/btn.png', DEFAULT_BTN);

  // junction 故意指向一个诱饵目录而非 frameworkSrc 自身，与 materialize.test.mjs 同理：
  // 否则"经 junction 拷来的字节"与"从真源拷来的字节"完全相同，测不出 Critical 1 那类 bug。
  const frameworkDecoy = join(root, 'decoy', 'assets', 'framework');
  mkdirSync(frameworkDecoy, { recursive: true });
  put(frameworkDecoy, 'ui/atlas-hall/btn.png', DEFAULT_BTN);
  put(frameworkDecoy, 'ui/atlas-hall/__decoy_marker__.png', DEFAULT_BTN);

  const gamesDir = join(root, 'games');
  const gameDir = join(gamesDir, 'demo');
  mkdirSync(join(gameDir, 'assets'), { recursive: true });
  writeFileSync(join(gameDir, 'package.json'), JSON.stringify({ name: 'demo', creator: { version: gameVersion } }));
  symlinkSync(frameworkDecoy, join(gameDir, 'assets', 'framework'), LINK_TYPE);

  return { root, hostProject, frameworkSrc, frameworkDecoy, gamesDir, gameDir, workspace: join(root, 'build-workspace') };
}
function cleanup(root) { rmSync(root, { recursive: true, force: true }); }

function baseOpts(s, extra = {}) {
  return {
    gamesDir: s.gamesDir, frameworkSrc: s.frameworkSrc, hostProject: s.hostProject,
    workspace: s.workspace, platform: 'web-mobile',
    frameworkCommit: 'abc1234', now: '2026-08-27T00:00:00.000Z',
    runBuild: () => {},
    ...extra,
  };
}

test('buildGame 走通全流程：实体化 → 合成 → 调构建 → 写 build-info', () => {
  const s = scaffold();
  try {
    put(s.gameDir, 'assets/game/override/atlas-hall/btn.png', SKINNED);
    const calls = [];
    const r = buildGame('demo', baseOpts(s, { runBuild: (dir, p) => calls.push([dir, p]) }));

    assert.ok(readFileSync(join(r.workspaceDir, 'assets', 'framework', 'ui', 'atlas-hall', 'btn.png')).equals(SKINNED));
    assert.ok(readFileSync(join(s.frameworkSrc, 'ui', 'atlas-hall', 'btn.png')).equals(DEFAULT_BTN), '框架真源必须只读：合成只能发生在临时工作区');
    assert.ok(!existsSync(join(r.workspaceDir, 'assets', 'framework', 'ui', 'atlas-hall', '__decoy_marker__.png')),
      'framework 必须来自 frameworkSrc 真源，不能残留 junction 诱饵目标独有的文件（Critical 1）');
    assert.equal(calls.length, 1);
    assert.equal(calls[0][0], r.workspaceDir);
    assert.equal(calls[0][1], 'web-mobile');

    const info = JSON.parse(readFileSync(join(r.workspaceDir, 'build-info.json'), 'utf8'));
    assert.equal(info.game, 'demo');
    assert.equal(info.frameworkCommit, 'abc1234');
    assert.equal(info.platform, 'web-mobile');
    assert.deepEqual(info.skin, { matched: 1, frameworkTotal: 1 });
  } finally { cleanup(s.root); }
});

test('buildGame 在引擎版本不一致时中止，且不调用构建', () => {
  const s = scaffold('3.8.6');
  try {
    let called = false;
    assert.throws(
      () => buildGame('demo', baseOpts(s, { runBuild: () => { called = true; } })),
      /引擎版本不一致/,
    );
    assert.equal(called, false);
  } finally { cleanup(s.root); }
});

test('buildGame 在皮肤校验失败时中止，且不调用构建', () => {
  const s = scaffold();
  try {
    put(s.gameDir, 'assets/game/override/atlas-hall/typo.png', 'X');
    let called = false;
    assert.throws(
      () => buildGame('demo', baseOpts(s, { runBuild: () => { called = true; } })),
      /皮肤覆盖校验未通过/,
    );
    assert.equal(called, false);
  } finally { cleanup(s.root); }
});

test('buildGame 重复构建：清掉旧工作区后重建（幂等）', () => {
  const s = scaffold();
  try {
    const opts = baseOpts(s);
    buildGame('demo', opts);
    const r2 = buildGame('demo', opts);   // 不应因目标已存在而抛错
    assert.ok(existsSync(join(r2.workspaceDir, 'build-info.json')));
  } finally { cleanup(s.root); }
});

test('buildGame 对不存在的子游戏抛错', () => {
  const s = scaffold();
  try {
    assert.throws(() => buildGame('nosuch', baseOpts(s)), /找不到子游戏工程/);
  } finally { cleanup(s.root); }
});