import { test } from 'node:test';
import assert from 'node:assert/strict';
import { join } from 'node:path';
import { mkdirSync, writeFileSync, rmSync, mkdtempSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { deflateSync } from 'node:zlib';
import { listAssets, readPngSize, validateOverrides } from '../lib/skin.mjs';

// ---- 测试辅助：零依赖生成指定尺寸的 PNG ----
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) {
  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));
  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)),
  ]);
}
function writeFile(dir, rel, content) {
  const p = join(dir, ...rel.split('/'));
  mkdirSync(join(p, '..'), { recursive: true });
  writeFileSync(p, content);
  return p;
}
function png(dir, rel, w = 64, h = 64) { return writeFile(dir, rel, makePng(w, h)); }

function makeDirs() {
  const root = mkdtempSync(join(tmpdir(), 'youle-skin-'));
  const fw = join(root, 'ui'); const ov = join(root, 'override');
  mkdirSync(fw, { recursive: true }); mkdirSync(ov, { recursive: true });
  return { root, fw, ov };
}
function cleanup(root) { rmSync(root, { recursive: true, force: true }); }

// ---- listAssets ----
test('listAssets 返回正斜杠相对路径，排除 .meta 与 .gitkeep', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png');
    writeFile(d.fw, 'atlas-hall/btn.png.meta', '{}');
    writeFile(d.fw, 'audio/.gitkeep', '');
    writeFile(d.fw, 'audio/click.wav', 'x');
    assert.deepEqual(listAssets(d.fw).sort(), ['atlas-hall/btn.png', 'audio/click.wav']);
  } finally { cleanup(d.root); }
});

test('listAssets 对不存在的目录返回空数组', () => {
  assert.deepEqual(listAssets('/no/such/dir'), []);
});

// ---- readPngSize ----
test('readPngSize 读出宽高；非 PNG 返回 null', () => {
  const d = makeDirs();
  try {
    const p = png(d.fw, 'a.png', 128, 64);
    assert.deepEqual(readPngSize(p), { width: 128, height: 64 });
    const w = writeFile(d.fw, 'b.wav', 'not a png');
    assert.equal(readPngSize(w), null);
  } finally { cleanup(d.root); }
});

// ---- validateOverrides：正常命中 ----
test('同名同尺寸图片：命中，无错误', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png', 64, 64);
    png(d.ov, 'atlas-hall/btn.png', 64, 64);
    const r = validateOverrides(d.fw, d.ov);
    assert.deepEqual(r.errors, []);
    assert.deepEqual(r.matched, ['atlas-hall/btn.png']);
  } finally { cleanup(d.root); }
});

test('框架有、子游戏未覆盖：不是错误', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/a.png');
    png(d.fw, 'atlas-hall/b.png');
    png(d.ov, 'atlas-hall/a.png');
    const r = validateOverrides(d.fw, d.ov);
    assert.deepEqual(r.errors, []);
    assert.deepEqual(r.matched, ['atlas-hall/a.png']);
  } finally { cleanup(d.root); }
});

// ---- validateOverrides：孤儿 ----
test('override 在框架里找不到对应路径 → orphan', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png');
    png(d.ov, 'atlas-hall/typo.png');
    const r = validateOverrides(d.fw, d.ov);
    assert.equal(r.errors.length, 1);
    assert.equal(r.errors[0].code, 'orphan');
    assert.equal(r.errors[0].path, 'atlas-hall/typo.png');
  } finally { cleanup(d.root); }
});

test('同名不同扩展名 → orphan，且提示框架里的实际扩展名', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png');
    writeFile(d.ov, 'atlas-hall/btn.jpg', 'x');
    const r = validateOverrides(d.fw, d.ov);
    assert.equal(r.errors[0].code, 'orphan');
    assert.match(r.errors[0].message, /btn\.png/);
  } finally { cleanup(d.root); }
});

// ---- validateOverrides：尺寸 ----
test('图片尺寸不同且未带 meta → size-mismatch', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png', 64, 64);
    png(d.ov, 'atlas-hall/btn.png', 128, 128);
    const r = validateOverrides(d.fw, d.ov);
    assert.equal(r.errors.length, 1);
    assert.equal(r.errors[0].code, 'size-mismatch');
    assert.match(r.errors[0].message, /64x64/);
    assert.match(r.errors[0].message, /128x128/);
  } finally { cleanup(d.root); }
});

test('图片尺寸不同但自带 meta（例外通道）→ 通过', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png', 64, 64);
    png(d.ov, 'atlas-hall/btn.png', 128, 128);
    writeFile(d.ov, 'atlas-hall/btn.png.meta', '{"ver":"1.0.0"}');
    const r = validateOverrides(d.fw, d.ov);
    assert.deepEqual(r.errors, []);
    assert.deepEqual(r.matched, ['atlas-hall/btn.png']);
  } finally { cleanup(d.root); }
});

test('非图片资源（音效）不做尺寸校验', () => {
  const d = makeDirs();
  try {
    // 用真实的、有效的、尺寸不同的 PNG 字节，但扩展名是 .wav
    // 如果 isImage() 门控被删掉，因为尺寸不同会报 size-mismatch，用例失败
    writeFile(d.fw, 'audio/click.wav', makePng(64, 64));
    writeFile(d.ov, 'audio/click.wav', makePng(256, 256));
    const r = validateOverrides(d.fw, d.ov);
    assert.deepEqual(r.errors, []);
  } finally { cleanup(d.root); }
});

// ---- validateOverrides：尺寸不可读 ----
test('图片尺寸无法读取（非 PNG）→ size-unreadable', () => {
  const d = makeDirs();
  try {
    png(d.fw, 'atlas-hall/btn.png', 64, 64);
    writeFile(d.ov, 'atlas-hall/btn.png', 'this is not a png but it is long enough to pass the 24-byte length check');
    const r = validateOverrides(d.fw, d.ov);
    assert.equal(r.errors.length, 1);
    assert.equal(r.errors[0].code, 'size-unreadable');
    assert.match(r.errors[0].message, /无法读取尺寸/);
    assert.match(r.errors[0].message, /PNG/);
    assert.equal(r.matched.length, 0);
  } finally { cleanup(d.root); }
});

test('readPngSize 长度足够但签名不对 → 返回 null', () => {
  const d = makeDirs();
  try {
    // 构造一个 24 字节以上、但 PNG 签名不对的数据
    const buf = Buffer.alloc(30, 0x00);
    buf.write('NOTPNG', 1, 'ascii');
    const p = writeFile(d.fw, 'test.png', buf);
    assert.equal(readPngSize(p), null);
  } finally { cleanup(d.root); }
});

// ---- validateOverrides：Spine ----
test('Spine 整套覆盖 → 通过，且贴图豁免尺寸校验', () => {
  const d = makeDirs();
  try {
    writeFile(d.fw, 'spine/hero/hero.json', '{}');
    writeFile(d.fw, 'spine/hero/hero.atlas', 'atlas');
    png(d.fw, 'spine/hero/hero.png', 64, 64);
    writeFile(d.ov, 'spine/hero/hero.json', '{"v":2}');
    writeFile(d.ov, 'spine/hero/hero.atlas', 'atlas2');
    png(d.ov, 'spine/hero/hero.png', 256, 256);   // 尺寸不同也应通过
    const r = validateOverrides(d.fw, d.ov);
    assert.deepEqual(r.errors, []);
    assert.equal(r.matched.length, 3);
  } finally { cleanup(d.root); }
});

test('Spine 缺件 → spine-incomplete，并列出缺少的文件', () => {
  const d = makeDirs();
  try {
    writeFile(d.fw, 'spine/hero/hero.json', '{}');
    writeFile(d.fw, 'spine/hero/hero.atlas', 'atlas');
    png(d.fw, 'spine/hero/hero.png', 64, 64);
    png(d.ov, 'spine/hero/hero.png', 64, 64);     // 只换贴图
    const r = validateOverrides(d.fw, d.ov);
    assert.equal(r.errors.length, 1);
    assert.equal(r.errors[0].code, 'spine-incomplete');
    assert.match(r.errors[0].message, /hero\.json/);
    assert.match(r.errors[0].message, /hero\.atlas/);
  } finally { cleanup(d.root); }
});