import fs from 'node:fs';
import path from 'node:path';
import type Database from 'better-sqlite3';

const MIGRATIONS_DIR = path.join(__dirname, 'migrations');

export function migrate(db: Database.Database): void {
  db.exec(`
    CREATE TABLE IF NOT EXISTS _migrations (
      name TEXT PRIMARY KEY,
      applied_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now'))
    )
  `);

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

  const files = fs
    .readdirSync(MIGRATIONS_DIR)
    .filter((f) => f.endsWith('.sql'))
    .sort();

  for (const file of files) {
    if (applied.has(file)) continue;

    const sql = fs.readFileSync(path.join(MIGRATIONS_DIR, file), 'utf-8');
    const run = db.transaction(() => {
      db.exec(sql);
      db.prepare('INSERT INTO _migrations (name) VALUES (?)').run(file);
    });
    run();
    // eslint-disable-next-line no-console
    console.log(`Applied migration ${file}`);
  }
}