import { existsSync, readdirSync, statSync } from 'node:fs';
import path from 'node:path';

const root = process.cwd();
const dist = path.join(root, 'dist');
const excludedDirs = new Set(['.git', 'dist', 'node_modules']);

function collectFiles(dir, predicate = () => true) {
  const entries = readdirSync(dir, { withFileTypes: true });
  const files = [];

  for (const entry of entries) {
    const fullPath = path.join(dir, entry.name);

    if (entry.isDirectory()) {
      if (!excludedDirs.has(entry.name)) {
        files.push(...collectFiles(fullPath, predicate));
      }
      continue;
    }

    if (entry.isFile() && predicate(fullPath)) {
      files.push(fullPath);
    }
  }

  return files;
}

if (!existsSync(dist) || !statSync(dist).isDirectory()) {
  throw new Error('Missing dist directory. Run `npm run build` first.');
}

const missingHtmlFiles = collectFiles(root, (file) => file.endsWith('.html'))
  .map((file) => path.relative(root, file))
  .filter((relativePath) => !existsSync(path.join(dist, relativePath)));

const missingAssetFiles = collectFiles(path.join(root, 'assets'))
  .map((file) => path.relative(root, file))
  .filter((relativePath) => !existsSync(path.join(dist, relativePath)));

const missingFiles = [...missingHtmlFiles, ...missingAssetFiles];

if (missingFiles.length > 0) {
  throw new Error(`Missing built files:\n${missingFiles.join('\n')}`);
}

console.log('All source HTML and static asset files are present in dist.');