require_relative '../../base'

module CCS
  module Components
    module GovUK
      class Pagination < Base
        # = GOV.UK Pagination Increment
        #
        # This generates the HTML for a  pagination increment, that is {Previous} and {Next}
        #
        # @!attribute [r] type
        #   @return [Symbol] The type of pagination increment
        # @!attribute [r] text
        #   @return [String] Default text for the pagination increment
        # @!attribute [r] default_text
        #   @return [String] Text for the pagination increment
        # @!attribute [r] block_is_level
        #   @return [Boolean] Flag to indicate if previous and next blocks are level
        # @!attribute [r] label_text
        #   @return [Boolean] Additional label text for when +block_is_level == true+

        class Increment < Base
          private

          attr_reader :type, :default_text, :text, :block_is_level, :label_text

          public

          # rubocop:disable Metrics/ParameterLists

          # @param type [Symbol] the type of increment, either +:prev+ or +:next+
          # @param default_text [String] the default text for the pagination increment
          # @param text [String] the text for the pagination increment
          # @param block_is_level [Boolean] when there are no items, this will be true and will add extra classes
          #                                 to the link to make the next and previous pagination links level
          # @param label_text [String] additional text for the link when the pagination block is level
          # @param options [Hash] options that will be used in customising the HTML
          #
          # @option options [String] :href the URL for the link
          # @option options  [ActionView::Helpers::FormBuilder] :form optional form builder used to create the button
          # @option options [Hash] :attributes any additional attributes that will added as part of the HTML

          def initialize(type:, default_text:, block_is_level:, text: nil, label_text: nil, **options)
            super(**options)

            @options[:attributes][:class] = "govuk-link govuk-pagination__link #{'pagination--button_as_link' if @options[:form]}".rstrip
            @options[:attributes][:rel] = type.to_s

            @type = type
            @default_text = default_text
            @text = text || default_text
            @block_is_level = block_is_level
            @label_text = label_text
          end

          # rubocop:enable Metrics/ParameterLists

          # Generates the HTML for the pagination increment link/button
          #
          # @yield the HTML for the increment button/link
          #
          # @return [ActiveSupport::SafeBuffer]

          def render(&)
            if options[:form]
              options[:form].button(**options[:attributes], &)
            else
              link_to(options[:href], **options[:attributes], &)
            end
          end

          private

          # Returns the classes for the link/button label
          #
          # @return [String]

          def pagination_text_classes
            "govuk-pagination__link-title #{'govuk-pagination__link-title--decorated' if block_is_level && !label_text}".rstrip
          end

          # Generates the icon for the pagination increment
          #
          # @return [ActiveSupport::SafeBuffer]

          def pagination_icon
            tag.svg(class: "govuk-pagination__icon govuk-pagination__icon--#{type}", xmlns: 'http://www.w3.org/2000/svg', height: '13', width: '15', aria: { hidden: 'true' }, focusable: 'false', viewBox: '0 0 15 13') do
              tag.path(d: self.class::PAGINATION_ICON_PATH)
            end
          end

          # Generates the label text for when the block is level
          #
          # @return [ActiveSupport::SafeBuffer]

          def pagination_icon_label_text
            return unless block_is_level && label_text

            concat(tag.span(':', class: 'govuk-visually-hidden'))
            concat(tag.span(label_text, class: 'govuk-pagination__link-label'))
          end
        end
      end
    end
  end
end