const { Client } = require('pg');
const fs = require('fs');
const path = require('path');

async function run() {
  const connectionString = process.env.DATABASE_URL;
  if (!connectionString) {
    console.log('DATABASE_URL not set – skipping migrations.');
    return;
  }

  console.log('Starting database migrations...');
  const client = new Client({
    connectionString,
    connectionTimeoutMillis: 10000,
  });
  await client.connect();

  // Create schema_migrations table if not exists
  await client.query(`
    CREATE TABLE IF NOT EXISTS public.schema_migrations (
      version VARCHAR(255) PRIMARY KEY,
      inserted_at TIMESTAMP WITH TIME ZONE DEFAULT timezone('utc'::text, now()) NOT NULL
    );
  `);

  const migrationsDir = path.join(__dirname, 'supabase', 'migrations');
  
  if (!fs.existsSync(migrationsDir)) {
    console.warn(`Migrations directory not found at: ${migrationsDir}`);
    await client.end();
    return;
  }

  const files = fs.readdirSync(migrationsDir).sort();

  for (const file of files) {
    if (!file.endsWith('.sql')) continue;

    const { rows } = await client.query('SELECT 1 FROM public.schema_migrations WHERE version = $1', [file]);
    if (rows.length === 0) {
      console.log(`Running migration: ${file}`);
      const sql = fs.readFileSync(path.join(migrationsDir, file), 'utf8');
      
      // We run the migration in a single transaction
      await client.query('BEGIN');
      try {
        await client.query(sql);
        await client.query('INSERT INTO public.schema_migrations (version) VALUES ($1)', [file]);
        await client.query('COMMIT');
        console.log(`Migration ${file} completed successfully.`);
      } catch (err) {
        await client.query('ROLLBACK');
        console.error(`Migration ${file} failed, rolled back.`);
        throw err;
      }
    } else {
      console.log(`Skipping migration: ${file} (already run)`);
    }
  }

  // Also check if we should run seed.sql (only if we run it for the first time or if products are empty)
  const seedFile = path.join(__dirname, 'supabase', 'seed.sql');
  if (fs.existsSync(seedFile)) {
    try {
      const { rows: productRows } = await client.query('SELECT 1 FROM public.products LIMIT 1');
      if (productRows.length === 0) {
        console.log('No products found. Seeding database with default products...');
        const seedSql = fs.readFileSync(seedFile, 'utf8');
        await client.query('BEGIN');
        try {
          await client.query(seedSql);
          await client.query('COMMIT');
          console.log('Database seeded successfully.');
        } catch (err) {
          await client.query('ROLLBACK');
          console.error('Seeding failed, rolled back.', err);
        }
      }
    } catch (e) {
      // In case products table check fails (e.g. initial_schema wasn't run or failed)
      console.error('Failed to run seed check/seed SQL', e);
    }
  }

  await client.end();
  console.log('Database migrations completed.');
}

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