const { AppError } = require('../shared/errors');
const ResponseHandler = require('../shared/response.handler');
const config = require('../config');

const errorHandler = (err, req, res, next) => {
  if (config.isDevelopment) {
    console.error('Error caught by middleware:', err);
  }

  if (err instanceof AppError) {
    return ResponseHandler.error(res, err.message, err.statusCode, err.errors);
  }

  if (
    err.name === 'SequelizeValidationError' ||
    err.name === 'SequelizeUniqueConstraintError'
  ) {
    const errors = err.errors
      ? err.errors.map((e) => ({ field: e.path, message: e.message }))
      : null;
    return ResponseHandler.badRequest(res, 'Validation error', errors);
  }

  if (err.name === 'ValidationError' && err.errors) {
    const errors = Object.keys(err.errors).map((key) => ({
      field: key,
      message: err.errors[key].message,
    }));
    return ResponseHandler.badRequest(res, 'Validation error', errors);
  }

  if (err.name === 'CastError') {
    return ResponseHandler.badRequest(res, 'Invalid ID format');
  }

  const message = config.isDevelopment ? err.message : 'Internal server error';
  return ResponseHandler.internalError(res, message, err);
};

module.exports = errorHandler;