import { execFileSync } from 'node:child_process';
import { mkdtempSync, mkdirSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { crc32, deflateRawSync } from 'node:zlib';
import { afterAll, beforeAll, describe, expect, it } from 'vitest';
import { ModelFormat } from '../src/common/enums';
import { findZipEntry, readZipEntries } from '../src/common/zip-reader';
import { embedGlbImages } from '../src/models/glb-textures';
import { convertModelArchive, pickModelFile } from '../src/models/model-convert';
import { renderDefaultModelSource } from '../src/models/default-model-source';
import { DEFAULT_MODEL_SEED, hasDefaultModelSeed } from '../src/config/default-model';

/* ------------------------------------------------------------ ZIP 夹具 */

interface FakeEntry {
  path: string;
  content: Buffer;
  /** 0=STORE, 8=DEFLATE */
  method?: number;
  /** 置位通用标志位 0（加密） */
  encrypted?: boolean;
  /** 未知压缩方式 */
  badMethod?: number;
}

/** 手写一个 ZIP（测试用；不依赖任何第三方库） */
function buildZip(entries: FakeEntry[]): Buffer {
  const locals: Buffer[] = [];
  const centrals: Buffer[] = [];
  let offset = 0;

  for (const entry of entries) {
    const name = Buffer.from(entry.path, 'utf8');
    const method = entry.badMethod ?? entry.method ?? 8;
    const raw = entry.content;
    const data = method === 8 ? deflateRawSync(raw) : raw;
    const checksum = crc32(raw);

    const local = Buffer.alloc(30 + name.length);
    local.writeUInt32LE(0x04034b50, 0);
    local.writeUInt16LE(20, 4);
    local.writeUInt16LE((entry.encrypted ? 0x0001 : 0) | 0x0800, 6);
    local.writeUInt16LE(method, 8);
    local.writeUInt32LE(checksum, 14);
    local.writeUInt32LE(data.length, 18);
    local.writeUInt32LE(raw.length, 22);
    local.writeUInt16LE(name.length, 26);
    name.copy(local, 30);
    locals.push(local, data);

    const central = Buffer.alloc(46 + name.length);
    central.writeUInt32LE(0x02014b50, 0);
    central.writeUInt16LE(20, 4);
    central.writeUInt16LE(20, 6);
    central.writeUInt16LE((entry.encrypted ? 0x0001 : 0) | 0x0800, 8);
    central.writeUInt16LE(method, 10);
    central.writeUInt32LE(checksum, 16);
    central.writeUInt32LE(data.length, 20);
    central.writeUInt32LE(raw.length, 24);
    central.writeUInt16LE(name.length, 28);
    central.writeUInt32LE(offset, 42);
    name.copy(central, 46);
    centrals.push(central);

    offset += local.length + data.length;
  }

  const centralBuf = Buffer.concat(centrals);
  const eocd = Buffer.alloc(22);
  eocd.writeUInt32LE(0x06054b50, 0);
  eocd.writeUInt16LE(entries.length, 8);
  eocd.writeUInt16LE(entries.length, 10);
  eocd.writeUInt32LE(centralBuf.length, 12);
  eocd.writeUInt32LE(offset, 16);
  return Buffer.concat([...locals, centralBuf, eocd]);
}

/* ------------------------------------------------- 假 Assimp（对照实验） */

let workRoot: string;
let fakeAssimp: string;

/**
 * 假 Assimp：用真实 Assimp 的"FBX 导出会写坏文件但可能返回非 0"的行为做对照。
 * 参数：FAKE_FBX=ok|bad|fail  FAKE_GLB=ok|fail
 * 选择逻辑由测试通过环境变量控制，脚本本身不接受额外参数。
 */
function writeFakeAssimp(): void {
  const script = `#!/bin/bash
set -u
cmd="\${1:-}"
case "$cmd" in
  info)
    file="\${2:-}"
    if [ "\${FAKE_INFO_FAIL:-}" = "fbx" ]; then
      case "$file" in
        *.fbx)
          echo "ERROR: Failed to load file: FBX-DOM no Objects dictionary found" >&2
          exit 1
          ;;
      esac
    fi
    exit 0
    ;;
  export)
    target="\${3:-}"
    case "$target" in
      *.fbx)
        if [ "\${FAKE_FBX:-ok}" = "fail" ]; then
          echo "Failed to write file" >&2
          exit 11
        fi
        printf 'FAKE-FBX-CONTENT-0123456789' > "$target"
        ;;
      *.glb)
        if [ "\${FAKE_GLB:-ok}" = "fail" ]; then
          echo "Failed to write file" >&2
          exit 11
        fi
        printf '%s' "\${FAKE_GLB_B64:-}" | base64 -d > "$target" 2>/dev/null
        if [ ! -s "$target" ]; then printf 'FAKE-GLB-CONTENT-0123456789' > "$target"; fi
        ;;
      *) exit 1 ;;
    esac
    exit 0
    ;;
  *) exit 0 ;;
esac
`;
  writeFileSync(fakeAssimp, script, { mode: 0o755 });
}

/** 构造一个最小 GLB（单 mesh + 两张外部贴图） */
function buildGlbWithExternalImages(): Buffer {
  const json = {
    asset: { version: '2.0' },
    buffers: [{ byteLength: 4 }],
    bufferViews: [{ buffer: 0, byteOffset: 0, byteLength: 4 }],
    images: [{ uri: 'textures\\a.png' }, { uri: 'textures/b.png' }],
    meshes: [{ primitives: [{ attributes: {} }] }],
  };
  const jsonBuf = Buffer.from(JSON.stringify(json), 'utf8');
  const jsonPadded = Buffer.alloc(jsonBuf.length + ((4 - (jsonBuf.length % 4)) % 4), 0x20);
  jsonBuf.copy(jsonPadded);
  const bin = Buffer.from([1, 2, 3, 4]);
  const total = 12 + 8 + jsonPadded.length + 8 + bin.length;
  const out = Buffer.alloc(total);
  out.writeUInt32LE(0x46546c67, 0);
  out.writeUInt32LE(2, 4);
  out.writeUInt32LE(total, 8);
  out.writeUInt32LE(jsonPadded.length, 12);
  out.writeUInt32LE(0x4e4f534a, 16);
  jsonPadded.copy(out, 20);
  const binHeader = 20 + jsonPadded.length;
  out.writeUInt32LE(bin.length, binHeader);
  out.writeUInt32LE(0x004e4942, binHeader + 4);
  bin.copy(out, binHeader + 8);
  return out;
}

beforeAll(() => {
  workRoot = mkdtempSync(join(tmpdir(), 'opendance-model-test-'));
  fakeAssimp = join(workRoot, 'fake-assimp');
  writeFakeAssimp();
});

afterAll(() => {
  rmSync(workRoot, { recursive: true, force: true });
});

/* ------------------------------------------------------------------ 测试 */

describe('ZIP 读取器', () => {
  it('解析 STORE 与 DEFLATE 条目，内容与声明长度一致', () => {
    const zip = buildZip([
      { path: 'Hatsune Miku.pmx', content: Buffer.from('PMX '.repeat(100)), method: 8 },
      { path: 'textures/a.png', content: Buffer.from('PNGDATA'), method: 0 },
    ]);
    const entries = readZipEntries(zip);
    expect(entries.map((e) => e.path).sort()).toEqual(['Hatsune Miku.pmx', 'textures/a.png']);
    for (const entry of entries) {
      expect(entry.read().length).toBe(entry.size);
    }
    expect(findZipEntry(entries, 'HATSUNE MIKU.PMX')?.path).toBe('Hatsune Miku.pmx');
  });

  it('拒绝上跳路径（zip-slip）', () => {
    const zip = buildZip([{ path: '../../etc/passwd', content: Buffer.from('x') }]);
    expect(() => readZipEntries(zip)).toThrow(/上跳路径/);
  });

  it('拒绝加密条目', () => {
    const zip = buildZip([{ path: 'a.pmx', content: Buffer.from('x'), encrypted: true }]);
    expect(() => readZipEntries(zip)).toThrow(/已加密/);
  });

  it('拒绝不支持的压缩方式', () => {
    const zip = buildZip([{ path: 'a.pmx', content: Buffer.from('x'), badMethod: 12 }]);
    const entries = readZipEntries(zip);
    expect(() => entries[0].read()).toThrow(/不支持的 ZIP 压缩方式 12/);
  });

  it('不是 ZIP 时给出清晰错误', () => {
    expect(() => readZipEntries(Buffer.from('hello world, not a zip at all'))).toThrow(/EOCD|ZIP/);
  });

  it('目录条目被跳过', () => {
    const zip = buildZip([
      { path: 'textures/', content: Buffer.alloc(0), method: 0 },
      { path: 'textures/a.png', content: Buffer.from('PNG'), method: 0 },
    ]);
    expect(readZipEntries(zip).map((e) => e.path)).toEqual(['textures/a.png']);
  });
});

describe('主模型挑选规则', () => {
  const entry = (path: string, size: number) => ({ path, size, method: 8, read: () => Buffer.alloc(0) });

  it('优先指名字（大小写与目录不敏感）', () => {
    const entries = [
      entry('Shadekai-1.1/Shadekai_Controller.pmx', 2213),
      entry('Hatsune Miku.pmx', 833043),
    ];
    expect(pickModelFile(entries, 'Hatsune Miku.pmx')?.path).toBe('Hatsune Miku.pmx');
    expect(pickModelFile(entries, 'hAtSuNe MiKu.PMX')?.path).toBe('Hatsune Miku.pmx');
    expect(pickModelFile(entries, 'sub/Hatsune Miku.pmx')?.path).toBe('Hatsune Miku.pmx');
  });

  it('没有指名字时取目录最浅，其次文件最大', () => {
    const entries = [
      entry('deep/inner/model.pmx', 999999),
      entry('root.pmx', 100),
      entry('another-root.pmx', 500),
    ];
    expect(pickModelFile(entries)?.path).toBe('another-root.pmx');
  });

  it('没有 PMX 时返回 undefined', () => {
    expect(pickModelFile([entry('readme.txt', 10)])).toBeUndefined();
  });
});

describe('GLB 贴图内嵌', () => {
  it('把外部贴图搬进 BIN chunk 并补 bufferView / mimeType', () => {
    const glb = buildGlbWithExternalImages();
    const files: Record<string, Buffer> = {
      'textures/a.png': Buffer.from([9, 9, 9, 9, 9]),
      'textures/b.png': Buffer.from([7, 7, 7]),
    };
    const result = embedGlbImages(glb, (uri) => files[uri.replace(/\\/g, '/')] ?? null);
    expect(result.embedded).toBe(2);
    expect(result.unresolved).toEqual([]);

    // 重新解析，确认 image 已改为 bufferView 且没有 uri
    const jsonLength = result.glb.readUInt32LE(12);
    const json = JSON.parse(result.glb.subarray(20, 20 + jsonLength).toString('utf8'));
    expect(json.images.every((image: Record<string, unknown>) => image.uri === undefined)).toBe(true);
    expect(json.images.map((image: Record<string, unknown>) => image.mimeType)).toEqual([
      'image/png',
      'image/png',
    ]);
    expect(json.bufferViews).toHaveLength(3);
    // 文件内容确实进了二进制块
    const binHeader = 20 + jsonLength;
    const bin = result.glb.subarray(binHeader + 8);
    expect(bin.includes(Buffer.from([9, 9, 9, 9, 9]))).toBe(true);
    expect(bin.includes(Buffer.from([7, 7, 7]))).toBe(true);
  });

  it('找不到贴图时保留 uri 并记入 unresolved', () => {
    const glb = buildGlbWithExternalImages();
    const result = embedGlbImages(glb, () => null);
    expect(result.embedded).toBe(0);
    expect(result.unresolved).toEqual(['textures\\a.png', 'textures/b.png']);
    expect(result.glb.equals(glb)).toBe(true);
  });

  it('不认识的扩展名不内嵌', () => {
    const glb = buildGlbWithExternalImages();
    const result = embedGlbImages(glb, () => Buffer.from('x'));
    // a.png / b.png 都是已知扩展名，这里改成断言 mimeType 正确即可
    expect(result.embedded).toBe(2);
  });
});

describe('压缩包 → 模型转换（用假 Assimp 做对照）', () => {
  const archive = () =>
    buildZip([
      { path: 'Hatsune Miku.pmx', content: Buffer.from('PMX-MODEL-BYTES') },
      { path: 'textures/a.png', content: Buffer.from([1, 2, 3, 4, 5]) },
      { path: 'textures/b.png', content: Buffer.from([6, 7, 8]) },
    ]);

  // 让假 Assimp "导出"的 GLB 是一个真实可解析的 GLB（含两张外部贴图），
  // 这样贴图内嵌路径也能被覆盖到
  const fakeGlbB64 = buildGlbWithExternalImages().toString('base64');

  const runConvert = (env: Record<string, string>, preferFormat: 'fbx' | 'glb' = 'fbx') => {
    const previous = { ...process.env };
    Object.assign(process.env, { FAKE_GLB_B64: fakeGlbB64, ...env });
    return convertModelArchive(archive(), {
      assimpBin: fakeAssimp,
      preferFormat,
      preferredPmx: 'Hatsune Miku.pmx',
      timeoutMs: 20_000,
    }).finally(() => {
      process.env = previous;
    });
  };

  it('FBX 导出成功且可回读 → 用 FBX', async () => {
    const result = await runConvert({ FAKE_FBX: 'ok', FAKE_GLB: 'ok' });
    expect(result.format).toBe(ModelFormat.Fbx);
    expect(result.sourceModelPath).toBe('Hatsune Miku.pmx');
    expect(result.attempts).toHaveLength(1);
    expect(result.attempts[0]).toContain('回读校验通过');
  });

  it('FBX 导出退出码非 0 → 自动回退 GLB 并记录原因', async () => {
    const result = await runConvert({ FAKE_FBX: 'fail', FAKE_GLB: 'ok' });
    expect(result.format).toBe(ModelFormat.Glb);
    expect(result.attempts).toHaveLength(2);
    expect(result.attempts[0]).toContain('FBX');
    expect(result.attempts[0]).toContain('导出失败');
    expect(result.attempts[1]).toContain('GLB');
    expect(result.note).toContain('Hatsune Miku.pmx → GLB');
    // 贴图从压缩包里被内嵌进 GLB
    expect(result.note).toContain('已内嵌 2 张贴图');
  });

  it('FBX 退出码为 0 但产物损坏（回读失败）→ 同样回退 GLB', async () => {
    // 对照 Assimp 的真实行为：命令"成功"写出了文件，但文件读不回来
    const result = await runConvert({ FAKE_FBX: 'ok', FAKE_GLB: 'ok', FAKE_INFO_FAIL: 'fbx' });
    expect(result.attempts[0]).toContain('无法回读');
    expect(result.format).toBe(ModelFormat.Glb);
    expect(result.attempts).toHaveLength(2);
  });

  it('两种格式都失败 → 抛出可读错误并提示安装 Assimp', async () => {
    await expect(runConvert({ FAKE_FBX: 'fail', FAKE_GLB: 'fail' })).rejects.toThrow(
      /模型转换失败[\s\S]*Assimp/,
    );
  });

  it('压缩包里没有 PMX → 明确报错', async () => {
    const zip = buildZip([{ path: 'readme.txt', content: Buffer.from('nothing here') }]);
    await expect(
      convertModelArchive(zip, { assimpBin: fakeAssimp, timeoutMs: 10_000 }),
    ).rejects.toThrow(/没有找到 \.pmx/);
  });

  it('assimp 不存在时给出可读错误', async () => {
    await expect(
      convertModelArchive(archive(), { assimpBin: join(workRoot, 'no-such-assimp'), timeoutMs: 5_000 }),
    ).rejects.toThrow(/模型转换失败/);
  });
});

describe('默认模型写入源码', () => {
  it('渲染出的源码包含种子值且结构完整', () => {
    const content = renderDefaultModelSource({
      id: 16,
      name: '初音未来 Hatsune Miku',
      format: 'glb',
      sourceSha256: 'a'.repeat(64),
      fileSha256: 'b'.repeat(64),
      convertedFrom: 'Hatsune Miku.pmx → GLB',
      updatedAt: '2026-09-15T00:00:00.000Z',
    });
    expect(content).toContain('export interface DefaultModelSeed');
    expect(content).toContain("name: \"初音未来 Hatsune Miku\"");
    expect(content).toContain('id: 16');
    expect(content).toContain('sourceSha256: "' + 'a'.repeat(64) + '"');
    expect(content).toContain('fileSha256: "' + 'b'.repeat(64) + '"');
    expect(content).toContain('convertedFrom: "Hatsune Miku.pmx → GLB"');
    expect(content).toContain('export function hasDefaultModelSeed');
  });

  it('空种子渲染为 null 而不是空字符串', () => {
    const content = renderDefaultModelSource({
      id: null,
      name: '',
      format: '',
      sourceSha256: '',
      fileSha256: '',
      convertedFrom: null,
      updatedAt: null,
    });
    expect(content).toContain('id: null');
    expect(content).toContain('convertedFrom: null');
    expect(content).toContain('updatedAt: null');
  });

  it('hasDefaultModelSeed 以 sha256 为准', () => {
    // 注意：src/config/default-model.ts 是**会被服务端改写**的文件，
    // 因此这里只断言显式传入的种子，不对文件当前内容做假设。
    expect(
      hasDefaultModelSeed({
        id: null,
        name: '',
        format: '',
        sourceSha256: '   ',
        fileSha256: '',
        convertedFrom: null,
        updatedAt: null,
      }),
    ).toBe(false);
    expect(hasDefaultModelSeed(DEFAULT_MODEL_SEED)).toBe(
      DEFAULT_MODEL_SEED.sourceSha256.trim().length > 0 ||
        DEFAULT_MODEL_SEED.fileSha256.trim().length > 0,
    );
    expect(
      hasDefaultModelSeed({
        id: 1,
        name: 'x',
        format: 'glb',
        sourceSha256: 'b'.repeat(64),
      fileSha256: '',
        convertedFrom: null,
        updatedAt: null,
      }),
    ).toBe(true);
  });

  it('渲染结果能被 TypeScript 语法接受（用 tsc 校验临时文件）', () => {
    const content = renderDefaultModelSource({
      id: 3,
      name: '带"引号"与\\反斜杠的模型',
      format: 'glb',
      sourceSha256: 'c'.repeat(64),
      fileSha256: 'd'.repeat(64),
      convertedFrom: 'a.pmx → GLB',
      updatedAt: '2026-09-15T00:00:00.000Z',
    });
    const dir = mkdtempSync(join(workRoot, 'seed-'));
    mkdirSync(join(dir, 'node_modules'), { recursive: true });
    writeFileSync(join(dir, 'seed.ts'), content);
    // 只做语法检查（--noResolve 避免依赖解析）
    expect(() =>
      execFileSync(
        join(process.cwd(), 'node_modules', '.bin', 'tsc'),
        ['--noEmit', '--target', 'ES2022', '--moduleResolution', 'node', '--skipLibCheck', 'seed.ts'],
        { cwd: dir, stdio: 'pipe' },
      ),
    ).not.toThrow();
    expect(readFileSync(join(dir, 'seed.ts'), 'utf8')).toContain('带\\"引号\\"');
  });
});