// ============================================================
// 打包后生成 update-info.json（含渠道/版本类型/SHA512/blockmap）
//
// 用法（由 build.mjs 调用）：
//   node build/scripts/generate-update-info.mjs <platform> <version> <channel> <edition> <ossPrefix> <releaseDirName>
//
// 也支持手动调用：
//   node build/scripts/generate-update-info.mjs <platform> <version> [channel] [edition] [ossPrefix] [releaseDirName] [--url <url>] [--blockmap-url <url>]
//
// 环境变量（可选）：
//   UPDATE_DOWNLOAD_BASE — OSS 下载基地址
//   UPDATE_FORCE         — 是否强制更新，默认 false
//   UPDATE_MIN_VERSION   — 最低兼容版本，默认 0.0.0
//   UPDATE_CHANGELOG     — 覆盖 CHANGELOG.md 中的日志内容
// ============================================================

import { readFileSync, writeFileSync, readdirSync, statSync } from 'node:fs';
import { join, dirname } from 'node:path';
import { fileURLToPath } from 'node:url';
import { createHash } from 'node:crypto';

const __dirname = dirname(fileURLToPath(import.meta.url));
const ROOT = join(__dirname, '..', '..');

// ---------- 参数解析 ----------

const args = process.argv.slice(2);

let urlOverride = '';
let blockmapUrlOverride = '';
const positional = [];
for (let i = 0; i < args.length; i++) {
  if (args[i] === '--url' && args[i + 1]) {
    urlOverride = args[++i];
  } else if (args[i] === '--blockmap-url' && args[i + 1]) {
    blockmapUrlOverride = args[++i];
  } else if (!args[i].startsWith('--')) {
    positional.push(args[i]);
  }
}

const platform = positional[0];
const version = positional[1];
const channel = positional[2] || 'stable';
const edition = positional[3] || 'personal';
const ossPrefix = positional[4] || `releases/${version}`;
const releaseDirName = positional[5] || version;

if (!platform || !version) {
  console.error('用法: node build/scripts/generate-update-info.mjs <platform> <version> [channel] [edition] [ossPrefix] [releaseDirName]');
  process.exit(1);
}

const productName = '船长·HeiXiu';

// ---------- 查找安装包 ----------

const releaseDir = join(ROOT, 'release', releaseDirName);

let installerPath;
try {
  const files = readdirSync(releaseDir);
  const exts = platform === 'win32' ? ['.exe'] : platform === 'darwin' ? ['.dmg'] : ['.AppImage'];
  const match = files.find((f) => exts.some((ext) => f.endsWith(ext)));
  if (!match) {
    console.error(`未在 ${releaseDir} 中找到安装包文件`);
    process.exit(1);
  }
  installerPath = join(releaseDir, match);
  console.log(`找到安装包: ${match}`);
} catch {
  console.error(`目录不存在: ${releaseDir}\n请先执行构建（如 npm run build:win）`);
  process.exit(1);
}

// ---------- 计算文件信息 ----------

const fileBuffer = readFileSync(installerPath);
const stats = statSync(installerPath);

const sha512 = createHash('sha512').update(fileBuffer).digest('base64').replace(/\r?\n/g, '');
const fileSize = stats.size;

console.log(`文件大小: ${(fileSize / 1024 / 1024).toFixed(2)} MB`);
console.log(`SHA512: ${sha512.slice(0, 32)}...`);

// ---------- 查找 blockmap 文件 ----------

let blockMapUrl;
let blockMapSize;

try {
  const blockmapFile = readdirSync(releaseDir).find((f) => f.endsWith('.blockmap'));
  if (blockmapFile) {
    const blockmapPath = join(releaseDir, blockmapFile);
    const blockmapStats = statSync(blockmapPath);
    blockMapSize = blockmapStats.size;

    if (blockmapUrlOverride) {
      blockMapUrl = blockmapUrlOverride;
    } else {
      const downloadBase = process.env.UPDATE_DOWNLOAD_BASE || 'https://heixiu.oss-cn-hangzhou.aliyuncs.com';
      blockMapUrl = `${downloadBase.replace(/\/+$/, '')}/${ossPrefix}/${encodeURI(blockmapFile)}`;
    }

    console.log(`Blockmap: ${blockmapFile} (${(blockMapSize / 1024).toFixed(2)} KB)`);
    console.log(`Blockmap URL: ${blockMapUrl}`);
  }
} catch {
  blockMapUrl = undefined;
  blockMapSize = undefined;
}

// ---------- 构建下载 URL ----------

const fileName = installerPath.split(/[/\\]/).pop();

let downloadUrl;
if (urlOverride) {
  downloadUrl = urlOverride;
  console.log(`下载 URL（手动指定）: ${downloadUrl}`);
} else {
  const downloadBase = process.env.UPDATE_DOWNLOAD_BASE || 'https://heixiu.oss-cn-hangzhou.aliyuncs.com';
  downloadUrl = `${downloadBase.replace(/\/+$/, '')}/${ossPrefix}/${encodeURI(fileName)}`;
  console.log(`下载 URL（自动拼接）: ${downloadUrl}`);
}

// ---------- 读取更新日志 ----------

let changelog;
if (process.env.UPDATE_CHANGELOG) {
  changelog = process.env.UPDATE_CHANGELOG;
} else {
  const changelogPath = join(ROOT, 'CHANGELOG.md');
  try {
    const changelogContent = readFileSync(changelogPath, 'utf-8');
    // 精确匹配当前版本块
    const escapedVersion = version.replace(/\./g, '\\.');
    const versionSection = changelogContent.match(
      new RegExp(`^##\\s+${escapedVersion}[^\\n]*\\n([\\s\\S]*?)(?=^##\\s|\\Z)`, 'm'),
    );
    if (versionSection) {
      changelog = versionSection[0].trim();
      console.log(`更新日志: 已从 CHANGELOG.md 提取 v${version} 条目`);
    } else {
      changelog = `## ${version}\n\n更新内容待补充`;
      console.warn(`⚠️  CHANGELOG.md 中未找到 v${version} 条目，使用占位内容`);
    }
  } catch {
    changelog = `## ${version}\n\n更新内容待补充`;
  }
}

// ---------- 其他配置 ----------

const forceUpdate = process.env.UPDATE_FORCE === 'true';
const minimumVersion = process.env.UPDATE_MIN_VERSION || '0.0.0';
const releaseDate = new Date().toISOString().slice(0, 10);

// ---------- 生成 JSON ----------

const updateInfo = {
  // --- 必填：API 返回字段 ---
  hasUpdate: true,
  latestVersion: version,
  downloadUrl,
  fileSize,
  sha512,
  changelog,
  releaseDate,
  forceUpdate,
  minimumVersion,

  // --- 渠道与版本类型（灰度测试关键字段）---
  channel,
  edition,

  // --- 增量更新 ---
  ...(blockMapUrl && { blockMapUrl }),
  ...(blockMapSize != null && { blockMapSize }),

  // --- 附加元数据 ---
  _meta: {
    platform,
    channel,
    edition,
    fileName,
    ossPrefix,
    blockmap: blockMapUrl ? { url: blockMapUrl, size: blockMapSize } : null,
    generatedAt: new Date().toISOString(),
  },
};

const outputPath = join(
  releaseDir,
  `${productName}-${platform}-v${version}-update-info.json`,
);

writeFileSync(outputPath, JSON.stringify(updateInfo, null, 2), 'utf-8');

console.log(`\n✅ 已生成: ${outputPath}`);
console.log(JSON.stringify(updateInfo, null, 2));