search_form.rb

class SearchForm
  include ActiveModel::Model
  
  %i[query lat lng].each do |name|
    define_method name do
      @params[name]
    end
  end
  
  def initialize(params)
    @params = params
  end
end

# Usage in controller
# @search_form = SearchForm.new(params.permit(:query, :lat, :lng))