import { Migration } from '@mikro-orm/migrations';

export class Migration20260218114512_orderCalc extends Migration {

  override async up(): Promise<void> {
    this.addSql(`
      CREATE OR REPLACE FUNCTION update_order_paid_amount()
      RETURNS TRIGGER AS $$
      BEGIN
        UPDATE orders o
        SET paid_amount = (
          SELECT COALESCE(SUM(p.amount), 0)
          FROM payments p
          WHERE p.order_id = COALESCE(NEW.order_id, OLD.order_id)
            AND p.status = 'Paid'
        )
        WHERE o.id = COALESCE(NEW.order_id, OLD.order_id);

        RETURN NULL;
      END;
      $$ LANGUAGE plpgsql;
    `);

    this.addSql(`
      CREATE TRIGGER trg_update_order_paid_amount
      AFTER INSERT OR UPDATE OR DELETE
      ON payments
      FOR EACH ROW
      EXECUTE FUNCTION update_order_paid_amount();
    `);

    this.addSql(`
      CREATE INDEX idx_payments_order_status
      ON payments(order_id, status);
    `);
  }

  override async down(): Promise<void> {
    this.addSql(`DROP TRIGGER IF EXISTS trg_update_order_paid_amount ON payments;`);
    this.addSql(`DROP FUNCTION IF EXISTS update_order_paid_amount;`);
    this.addSql(`DROP INDEX IF EXISTS idx_payments_order_status;`);
  }

}