require('dotenv').config();
const fs = require('fs');
const path = require('path');
const pool = require('../server/db');

function csvEscape(value) {
  const v = value == null ? '' : String(value);
  if (/[",\n\r]/.test(v)) return `"${v.replace(/"/g, '""')}"`;
  return v;
}

async function main() {
  const { rows } = await pool.query(`
    SELECT a.name AS artist, p.title AS painting, p.year
    FROM paintings p
    JOIN artists a ON a.id = p.artist_id
    ORDER BY a.name, p.year NULLS LAST, p.title
  `);

  const outDir = path.join(__dirname, '..', 'Output');
  fs.mkdirSync(outDir, { recursive: true });

  const header = 'artist,painting,year';
  const lines = rows.map((r) =>
    [csvEscape(r.artist), csvEscape(r.painting), csvEscape(r.year ?? '')].join(',')
  );
  const file = path.join(outDir, 'paintings.csv');
  fs.writeFileSync(file, `${[header, ...lines].join('\n')}\n`, 'utf8');
  console.log(`Wrote ${rows.length} rows to ${file}`);
  await pool.end();
}

main().catch((err) => {
  console.error(err);
  process.exit(1);
});