const fs = require('fs');
const path = require('path');

const LOG_FILE = path.join(__dirname, '..', 'compress.log');
const LEVEL_PRIORITY = { error: 0, warn: 1, info: 2, debug: 3 };
const currentLevel = LEVEL_PRIORITY[process.env.LOG_LEVEL || 'info'] ?? 2;

function formatTimestamp() {
  return new Date().toISOString();
}

function log(level, msg, meta) {
  if ((LEVEL_PRIORITY[level] ?? 2) > currentLevel) return;
  const ts = formatTimestamp();
  const metaStr = meta ? ' ' + JSON.stringify(meta) : '';
  const line = `[${ts}] [${level.toUpperCase()}] ${msg}${metaStr}`;
  process.stdout.write(line + '\n');
}

function logToFile(text) {
  const ts = formatTimestamp();
  fs.appendFile(LOG_FILE, `[${ts}] ${text}\n`, () => {});
}

module.exports = {
  info: (msg, meta) => log('info', msg, meta),
  warn: (msg, meta) => log('warn', msg, meta),
  error: (msg, meta) => log('error', msg, meta),
  debug: (msg, meta) => log('debug', msg, meta),
  logToFile,
};