// Regenerate skill-reviews/improved/**/SKILL.md from the content collection.
//
// Source of truth: src/content/reviews/{id}.md. Each file's frontmatter holds
// the review metadata (id, author, focus, wins, improve, extras,
// description); its body is the Markdown that becomes the SKILL.md file.
// This script reconstructs the SKILL.md frontmatter (name + description) and
// concatenates it with the body, so the committed output stays byte-identical
// to what the legacy catalog produced:
//
//   ---                                  <- SKILL.md frontmatter starts
//   name: <id>
//   description: <description>
//   ---
//
//   # <id>
//                                       <- body, as written in the .md file
//   ...
//
// Run from the repository root:
//
//   node scripts/build-skill-review.mjs && git diff --exit-code skill-reviews/
//
// A non-empty diff means the collection drifted from the committed output;
// regenerate after every entry edit.

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

const here = dirname(fileURLToPath(import.meta.url));
const root = dirname(here);
const REVIEWS_DIR = join(root, 'src', 'content', 'reviews');
const OUTPUT_DIR = join(root, 'skill-reviews', 'improved');

const parseFrontmatter = (text) => {
  // Strict shape: starts with `---\n`, ends at the next `---\n`, then body.
  if (!text.startsWith('---\n')) throw new Error('missing leading ---');
  const end = text.indexOf('\n---\n', 4);
  if (end === -1) throw new Error('missing closing ---');
  const yaml = text.slice(4, end);
  const body = text.slice(end + 5);
  const id = yaml.match(/^id:\s*"?([^"\n]+)"?\s*$/m)?.[1];
  const name = yaml.match(/^name:\s*"?([^"\n]+)"?\s*$/m)?.[1];
  const description = yaml.match(/^description:\s*"?((?:\\.|[^"\\])*)"?\s*$/m)?.[1];
  if (!id) throw new Error('frontmatter missing id');
  if (!name) throw new Error('frontmatter missing name');
  if (!description) throw new Error('frontmatter missing description');
  return { id, name, description, body };
};

const files = readdirSync(REVIEWS_DIR)
  .filter((f) => f.endsWith('.md'))
  .sort();
let count = 0;
for (const file of files) {
  const source = readFileSync(join(REVIEWS_DIR, file), 'utf8');
  const { id, name, description, body } = parseFrontmatter(source);
  // The body in the .md file starts with `# <name>\n\n` then the Markdown
  // content; strip a single leading newline if present so the reconstructed
  // SKILL.md matches the legacy `skill(...)` output exactly.
  const stripped = body.startsWith('\n') ? body.slice(1) : body;
  const output = `---\nname: ${name}\ndescription: ${description}\n---\n\n${stripped.trim()}\n`;
  const outPath = join(OUTPUT_DIR, id, 'SKILL.md');
  mkdirSync(dirname(outPath), { recursive: true });
  writeFileSync(outPath, output);
  count += 1;
}
console.log(`wrote ${count} improved skill drafts`);