import winston from 'winston';

const { combine, timestamp, json, printf, colorize, errors } = winston.format;

const devFormat = printf(({ level, message, timestamp, ...metadata }) => {
  let msg = `${timestamp} [${level}]: ${message}`;
  if (Object.keys(metadata).length > 0) {
    msg += ` ${JSON.stringify(metadata)}`;
  }
  return msg;
});

export const createLogger = (service: string): winston.Logger => {
  const isDev = process.env.NODE_ENV !== 'production';
  const logLevel = process.env.LOG_LEVEL || (isDev ? 'debug' : 'info');

  return winston.createLogger({
    level: logLevel,
    defaultMeta: { service },
    format: isDev
      ? combine(
          colorize(),
          timestamp({ format: 'HH:mm:ss' }),
          errors({ stack: true }),
          devFormat
        )
      : combine(
          timestamp(),
          json()
        ),
    transports: [
      new winston.transports.Console({
        stderrLevels: ['error'],
      }),
    ],
  });
};

export const logger = createLogger('App');