/**
 * Logger Utility
 * Winston-based structured logging
 */

import winston from 'winston';

export class Logger {
  private logger: winston.Logger;
  private context: string;

  constructor(context: string) {
    this.context = context;

    this.logger = winston.createLogger({
      level: process.env.LOG_LEVEL || 'info',
      format: winston.format.combine(
        winston.format.timestamp(),
        winston.format.errors({ stack: true }),
        winston.format.json()
      ),
      defaultMeta: { service: 'aimds-gateway', context },
      transports: [
        new winston.transports.Console({
          format: winston.format.combine(
            winston.format.colorize(),
            winston.format.printf(({ timestamp, level, message, context, ...meta }) => {
              const metaStr = Object.keys(meta).length > 0
                ? JSON.stringify(meta)
                : '';
              return `${timestamp} [${context}] ${level}: ${message} ${metaStr}`;
            })
          )
        }),
        new winston.transports.File({
          filename: 'logs/error.log',
          level: 'error'
        }),
        new winston.transports.File({
          filename: 'logs/combined.log'
        })
      ]
    });
  }

  debug(message: string, meta?: Record<string, unknown>): void {
    this.logger.debug(message, meta);
  }

  info(message: string, meta?: Record<string, unknown>): void {
    this.logger.info(message, meta);
  }

  warn(message: string, meta?: Record<string, unknown>): void {
    this.logger.warn(message, meta);
  }

  error(message: string, meta?: Record<string, unknown>): void {
    this.logger.error(message, meta);
  }

  child(childContext: string): Logger {
    return new Logger(`${this.context}:${childContext}`);
  }
}