/**
 * Patches @astrojs/starlight to handle undefined `data.head` in frontmatter.
 *
 * Starlight 0.37.x assumes docsSchema() defaults `head` to [] via Zod, but
 * the content loader doesn't always apply this default, causing:
 *   "Cannot read properties of undefined (reading 'some')"
 *
 * This adds a nullish coalescing fallback: `data.head ?? []`
 */

import { readFileSync, writeFileSync } from 'node:fs';

const file = 'node_modules/@astrojs/starlight/utils/head.ts';

try {
  let src = readFileSync(file, 'utf8');
  const target = 'config.head, data.head)';
  const replacement = 'config.head, data.head ?? [])';

  if (src.includes(replacement)) {
    console.log('[patch] head.ts already patched, skipping.');
    process.exit(0);
  }

  if (!src.includes(target)) {
    console.warn('[patch] Could not find target string in head.ts — Starlight may have been updated.');
    process.exit(0);
  }

  src = src.replace(target, replacement);
  writeFileSync(file, src, 'utf8');
  console.log('[patch] Patched head.ts: data.head ?? []');
} catch (err) {
  console.warn('[patch] Could not patch head.ts:', err.message);
}