class ActiveAdmin::Inputs::Filters::DateRangeInput

def gt_input_name
  column && column.type == :date ? "#{method}_gteq" : "#{method}_gteq_datetime"
end

def gt_input_placeholder
  I18n.t("active_admin.filters.predicates.from")
end

def input_html_options
  { size: 12,
    class: "datepicker",
    maxlength: 10 }.merge(options[:input_html] || {})
end

def input_html_options_for(input_name, placeholder)
  current_value = begin
                    #cast value to date object before rendering input
                    @object.public_send(input_name).to_s.to_date
                  rescue
                    nil
                  end
  { placeholder: placeholder,
    value: current_value ? current_value.strftime("%Y-%m-%d") : "" }.merge(input_html_options)
end

def lt_input_name
  column && column.type == :date ? "#{method}_lteq" : "#{method}_lteq_datetime"
end

def lt_input_placeholder
  I18n.t("active_admin.filters.predicates.to")
end

def to_html
  input_wrapping do
    [ label_html,
      builder.text_field(gt_input_name, input_html_options_for(gt_input_name, gt_input_placeholder)),
      builder.text_field(lt_input_name, input_html_options_for(lt_input_name, lt_input_placeholder)),
    ].join("\n").html_safe
  end
end