export enum LogLevel {
  DEBUG = 'DEBUG',
  INFO = 'INFO',
  WARN = 'WARN',
  ERROR = 'ERROR'
}

export class Logger {
  private static instance: Logger;
  private minLevel: LogLevel = LogLevel.INFO;

  static getInstance(): Logger {
    if (!Logger.instance) {
      Logger.instance = new Logger();
    }
    return Logger.instance;
  }

  setLevel(level: LogLevel): void {
    this.minLevel = level;
  }

  private shouldLog(level: LogLevel): boolean {
    const levels = [LogLevel.DEBUG, LogLevel.INFO, LogLevel.WARN, LogLevel.ERROR];
    return levels.indexOf(level) >= levels.indexOf(this.minLevel);
  }

  private log(level: LogLevel, message: string, context?: any): void {
    if (!this.shouldLog(level)) return;

    const timestamp = new Date().toISOString();
    const contextStr = context ? ` ${JSON.stringify(context)}` : '';
    const logMessage = `[${timestamp}] ${level}: ${message}${contextStr}`;
    
    console.error(logMessage);
  }

  debug(message: string, context?: any): void {
    this.log(LogLevel.DEBUG, message, context);
  }

  info(message: string, context?: any): void {
    this.log(LogLevel.INFO, message, context);
  }

  warn(message: string, context?: any): void {
    this.log(LogLevel.WARN, message, context);
  }

  error(message: string, context?: any): void {
    this.log(LogLevel.ERROR, message, context);
  }
}

// Export singleton instance
export const logger = Logger.getInstance();