const { Pool } = require('pg');

const pools = new Map();

function postgresUrl() { return process.env.DURIIN_POSTGRES_URL || process.env.DATABASE_URL; }

function poolFor(schema = 'intelligence') {
  const connectionString = postgresUrl();
  if (!connectionString) throw new Error('DURIIN_POSTGRES_URL is required');
  const key = `${connectionString}|${schema}`;
  if (!pools.has(key)) {
    pools.set(key, new Pool({
      connectionString,
      max: Math.max(1, Number(process.env.POSTGRES_HTTP_POOL_SIZE) || 4),
      options: `-c search_path=${schema},public`,
    }));
  }
  return pools.get(key);
}

async function all(schema, sql, params = []) { return (await poolFor(schema).query(sql, params)).rows; }
async function get(schema, sql, params = []) { return (await poolFor(schema).query(sql, params)).rows[0]; }

module.exports = { poolFor, all, get };