const LEVELS = { debug: 0, info: 1, warn: 2, error: 3 } as const;
type Level = keyof typeof LEVELS;

function getMinLevel(): Level {
  const raw = process.env['LOG_LEVEL'] ?? 'info';
  return (raw in LEVELS ? raw : 'info') as Level;
}

function log(level: Level, msg: string, meta?: Record<string, unknown>) {
  if (LEVELS[level] < LEVELS[getMinLevel()]) return;
  const ts = new Date().toISOString();
  const prefix = `[${ts}] [${level.toUpperCase()}]`;
  if (meta && Object.keys(meta).length > 0) {
    console.log(`${prefix} ${msg}`, JSON.stringify(meta));
  } else {
    console.log(`${prefix} ${msg}`);
  }
}

export const logger = {
  debug: (msg: string, meta?: Record<string, unknown>) => log('debug', msg, meta),
  info: (msg: string, meta?: Record<string, unknown>) => log('info', msg, meta),
  warn: (msg: string, meta?: Record<string, unknown>) => log('warn', msg, meta),
  error: (msg: string, meta?: Record<string, unknown>) => log('error', msg, meta),
};