require('dotenv').config();
const fs = require('fs');
const path = require('path');
const { Pool } = require('pg');

const pool = new Pool({ connectionString: process.env.DATABASE_URL });

async function migrate() {
  const migrationsDir = path.join(__dirname, '..', 'migrations');
  const files = fs.readdirSync(migrationsDir).filter(f => f.endsWith('.sql')).sort();

  // Ensure migrations tracking table exists
  await pool.query(`
    CREATE TABLE IF NOT EXISTS schema_migrations (
      filename VARCHAR(255) PRIMARY KEY,
      applied_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
    )
  `);

  for (const file of files) {
    const { rows } = await pool.query(
      'SELECT filename FROM schema_migrations WHERE filename = $1',
      [file]
    );
    if (rows.length > 0) {
      console.log(`  ✓ already applied: ${file}`);
      continue;
    }

    const sql = fs.readFileSync(path.join(migrationsDir, file), 'utf8');
    // Extract and run only the UP section (before the -- DOWN comment)
    const upSection = sql.split('-- DOWN')[0].trim();

    try {
      await pool.query(upSection);
      await pool.query('INSERT INTO schema_migrations (filename) VALUES ($1)', [file]);
      console.log(`  ✅ applied: ${file}`);
    } catch (err) {
      console.error(`  ❌ failed: ${file}`, err.message);
      process.exit(1);
    }
  }

  console.log('Migrations complete.');
  await pool.end();
}

migrate().catch(err => {
  console.error('Migration error:', err);
  process.exit(1);
});