import type { NextFunction, Request, Response } from 'express'
import type { ApiResponse } from '../../shared/types.js'
import { ERROR_CODES } from '../../shared/constants/errors.js'
import { isAppError, isNodeError } from '../../shared/errors/index.js'
import { logger } from '../utils/logger.js'

export const errorHandler = (err: unknown, _req: Request, res: Response, _next: NextFunction) => {
  let statusCode: number = 500
  let code: string = ERROR_CODES.INTERNAL_ERROR
  let message: string = 'Server internal error'
  let details: unknown = undefined

  if (isAppError(err)) {
    statusCode = err.statusCode
    code = err.code
    message = err.message
    details = err.details
  } else if (isNodeError(err)) {
    message = err.message
    if (process.env.NODE_ENV !== 'production') {
      details = { stack: err.stack, nodeErrorCode: err.code }
    }
  } else if (err instanceof Error) {
    message = err.message
    if (process.env.NODE_ENV !== 'production') {
      details = { stack: err.stack }
    }
  }

  logger.error(err)

  const response: ApiResponse<null> = {
    success: false,
    error: {
      code,
      message,
      details: process.env.NODE_ENV === 'production' ? undefined : details,
    },
  }

  res.status(statusCode).json(response)
}