import { mkdirSync, readdirSync, readFileSync } from 'node:fs';
import { dirname, join, resolve } from 'node:path';
import Database from 'better-sqlite3';
import { config as loadDotenv } from 'dotenv';

loadDotenv({
  path: [resolve(process.cwd(), '.env'), resolve(process.cwd(), '../../.env')],
});

const databaseUrl = process.env.DATABASE_URL;
if (!databaseUrl) {
  throw new Error('DATABASE_URL is required.');
}

const dbPath = resolve(process.cwd(), databaseUrl);
mkdirSync(dirname(dbPath), { recursive: true });

const db = new Database(dbPath);
db.pragma('foreign_keys = ON');
db.exec(`
  CREATE TABLE IF NOT EXISTS _migrations (
    name TEXT PRIMARY KEY,
    applied_at INTEGER NOT NULL
  );
`);

const applied = new Set(
  db
    .prepare('SELECT name FROM _migrations')
    .all()
    .map((row) => String((row as { name: string }).name)),
);

const migrationsDir = resolve(process.cwd(), 'migrations');
const files = readdirSync(migrationsDir)
  .filter((file) => file.endsWith('.sql'))
  .sort();

for (const file of files) {
  if (applied.has(file)) continue;
  const sql = readFileSync(join(migrationsDir, file), 'utf8');
  db.exec('BEGIN');
  try {
    db.exec(sql);
    db.prepare('INSERT INTO _migrations (name, applied_at) VALUES (?, ?)').run(file, Date.now());
    db.exec('COMMIT');
    console.log(`Applied migration ${file}`);
  } catch (error) {
    db.exec('ROLLBACK');
    throw error;
  }
}

db.close();