import { Request, Response, NextFunction } from 'express';
import logger from '../utils/logger';

export class AppError extends Error {
  statusCode: number;
  isOperational: boolean;

  constructor(message: string, statusCode: number = 500) {
    super(message);
    this.statusCode = statusCode;
    this.isOperational = true;

    Error.captureStackTrace(this, this.constructor);
  }
}

export const errorHandler = (
  err: Error | AppError,
  req: Request,
  res: Response,
  _next: NextFunction
): void => {
  if (err instanceof AppError) {
    logger.error('Application Error', {
      message: err.message,
      statusCode: err.statusCode,
      stack: err.stack,
      path: req.path,
      method: req.method,
    });

    res.status(err.statusCode).json({
      status: 'error',
      message: err.message,
    });
    return;
  }

  // Handle unexpected errors
  logger.error('Unexpected Error', {
    message: err.message,
    stack: err.stack,
    path: req.path,
    method: req.method,
  });

  res.status(500).json({
    status: 'error',
    message: 'An internal error occurred',
  });
};

export const notFoundHandler = (req: Request, res: Response): void => {
  res.status(404).json({
    status: 'error',
    message: `Route ${req.originalUrl} not found`,
  });
};

export const asyncHandler = (fn: Function) => {
  return (req: Request, res: Response, next: NextFunction) => {
    Promise.resolve(fn(req, res, next)).catch(next);
  };
};