/**
 * Lightweight structured logger.
 *
 * Honors LOG_LEVEL (debug | info | warn | error). Defaults to 'info'.
 * Output is single-line JSON for easy ingestion by log shippers.
 *
 * Note: requires config-free defaults so it can be imported anywhere without
 * pulling in config/index.js (which validates env on load).
 */

const LEVELS = { debug: 10, info: 20, warn: 30, error: 40 };

function configuredLevel() {
  const raw = (process.env.LOG_LEVEL || 'info').toLowerCase();
  return LEVELS[raw] ?? LEVELS.info;
}

function shouldEmit(level) {
  return LEVELS[level] >= configuredLevel();
}

function log(level, message, meta = {}) {
  if (!shouldEmit(level)) return;

  const entry = {
    ts: new Date().toISOString(),
    level,
    msg: message,
    ...meta,
  };
  const line = JSON.stringify(entry);

  if (level === 'error') console.error(line);
  else if (level === 'warn') console.warn(line);
  else console.log(line);
}

const logger = {
  debug: (msg, meta) => log('debug', msg, meta),
  info: (msg, meta) => log('info', msg, meta),
  warn: (msg, meta) => log('warn', msg, meta),
  error: (msg, meta) => log('error', msg, meta),
};

module.exports = logger;