import { execFileSync } from 'node:child_process';
import fs from 'node:fs';
import { createRequire } from 'node:module';
import path from 'node:path';
import process from 'node:process';
import { fileURLToPath } from 'node:url';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const appRoot = path.resolve(__dirname, '..');
const repoRoot = path.resolve(appRoot, '../..');
const requireFromApp = createRequire(path.join(appRoot, 'package.json'));
const monacoDtsDir = path.join(appRoot, 'monaco.dts');
const cacheDir = path.join(monacoDtsDir, '.cache');
const legacyOutputFile = path.join(monacoDtsDir, 'index.d.ts');
const outputFile = path.join(
  repoRoot,
  'packages/form-designer/src/utils/user-script/context/monaco/index.d.ts',
);
const globalLsBlock = [
  'declare global {',
  '  const ls: MonacoLsTypes.LsGlobal;',
  '}',
].join('\n');
const banner = [
  '// Auto-generated by `pnpm run monaco:dts:build`.',
  '// Do not edit this file directly.',
  '',
].join('\n');

function readJsonFile(filePath) {
  return JSON.parse(fs.readFileSync(filePath, 'utf8'));
}

function findPackageRoot(packageName) {
  let entryPath;
  try {
    entryPath = requireFromApp.resolve(packageName);
  } catch (error) {
    throw new Error(
      `[monaco:dts:build] 无法解析依赖 ${packageName}。请先在仓库根目录执行 pnpm install，`
      + `并确认 apps/lcdp/package.json 已声明该依赖。原始错误：${error.message}`,
    );
  }

  let currentDir = path.dirname(entryPath);
  while (currentDir !== path.dirname(currentDir)) {
    const packageJsonPath = path.join(currentDir, 'package.json');
    if (fs.existsSync(packageJsonPath)) {
      const packageJson = readJsonFile(packageJsonPath);
      if (packageJson.name === packageName) {
        return { root: currentDir, packageJson };
      }
    }
    currentDir = path.dirname(currentDir);
  }

  throw new Error(`[monaco:dts:build] 已解析 ${packageName}，但无法找到对应 package.json。`);
}

function resolvePackageBin(packageName, binName) {
  const { root, packageJson } = findPackageRoot(packageName);
  const binConfig = packageJson.bin;
  const binPath = typeof binConfig === 'string' ? binConfig : binConfig?.[binName];

  if (!binPath) {
    throw new Error(`[monaco:dts:build] ${packageName} 未声明 bin.${binName}。`);
  }

  const resolvedBinPath = path.resolve(root, binPath);
  if (!fs.existsSync(resolvedBinPath)) {
    throw new Error(`[monaco:dts:build] ${packageName} 的 bin.${binName} 不存在：${resolvedBinPath}`);
  }

  return resolvedBinPath;
}

// 通过 package.json 的 bin 字段定位 CLI，避免写死深层子路径或依赖 Windows/macOS 不一致的 .bin shim。
const tscBin = resolvePackageBin('typescript', 'tsc');
const apiExtractorBin = resolvePackageBin('@microsoft/api-extractor', 'api-extractor');

function runNodeScript(scriptPath, args) {
  execFileSync(process.execPath, [scriptPath, ...args], {
    cwd: appRoot,
    stdio: 'inherit',
    env: {
      ...process.env,
    },
  });
}

function validateOutput() {
  const content = fs.readFileSync(outputFile, 'utf8');
  const hasImportLikeLine = content.split('\n').some((line) => {
    const trimmed = line.trim();
    return trimmed.startsWith('import ')
      || (trimmed.startsWith('export ') && trimmed.includes(' from '));
  });
  if (hasImportLikeLine) {
    throw new Error('Generated Monaco d.ts still contains import/export-from statements.');
  }
  if (/\b(?:typeof\s+)?import\((['"]).+?\1\)/.test(content)) {
    throw new Error('Generated Monaco d.ts still contains external import type references.');
  }
  if (!content.includes('const ls: MonacoLsTypes.LsGlobal;')) {
    throw new Error('Generated Monaco d.ts is missing the global ls declaration.');
  }
}

function ensureGlobalLs() {
  const content = fs.readFileSync(outputFile, 'utf8');
  if (!content.includes('declare global {')) {
    const footer = 'export { }';
    const body = content.trimEnd().endsWith(footer)
      ? content.trimEnd().slice(0, -footer.length).trimEnd()
      : content.trimEnd();
    fs.writeFileSync(outputFile, `${body}\n\n${globalLsBlock}\n\nexport { }\n`);
  }
}

function addBanner() {
  const content = fs.readFileSync(outputFile, 'utf8');
  if (!content.startsWith('// Auto-generated')) {
    fs.writeFileSync(outputFile, `${banner}${content}`);
  }
}

function main() {
  fs.rmSync(cacheDir, { recursive: true, force: true });
  fs.rmSync(legacyOutputFile, { force: true });
  fs.rmSync(outputFile, { force: true });

  runNodeScript(tscBin, ['-p', 'monaco-types/tsconfig.json']);
  runNodeScript(apiExtractorBin, ['run', '--local', '--config', 'api-extractor.monaco.json']);

  ensureGlobalLs();
  validateOutput();
  addBanner();
  fs.rmSync(cacheDir, { recursive: true, force: true });
}

main();