module GovukPublishingComponents
  module Presenters
    # @private
    class ContextualNavigation
      attr_reader :content_item, :request_path, :query_parameters

      # @param content_item A content item hash with strings as keys
      # @param request_path `request.path`
      def initialize(content_item, request)
        @content_item = content_item
        @request_path = simple_smart_answer? ? content_item["base_path"] : request.path
        @query_parameters = request.query_parameters
      end

      def simple_smart_answer?
        content_item["document_type"] == "simple_smart_answer"
      end

      def html_publication_with_parent?
        (content_item["document_type"] == "html_publication") && parent_api_path
      end

      def parent_api_path
        parent = content_item.dig("links", "parent")&.first
        parent["base_path"] if parent
      end

      def taxon_breadcrumbs
        @taxon_breadcrumbs ||= ContentBreadcrumbsBasedOnTaxons.call(content_item)
      end

      def priority_breadcrumbs
        @priority_breadcrumbs ||= ContentBreadcrumbsBasedOnPriority.call(content_item, query_parameters)
      end

      def topic_breadcrumbs
        @topic_breadcrumbs ||= ContentBreadcrumbsBasedOnTopic.call(content_item)
      end

      def breadcrumbs
        breadcrumbs_based_on_ancestors
      end

      def finder_breadcrumbs
        return [] unless parent_finder

        [
          {
            title: "Home",
            url: "/",
          },
          {
            title: parent_finder["title"],
            url: parent_finder["base_path"],
          },
        ]
      end

      def use_taxon_breadcrumbs?
        content_is_tagged_to_a_live_taxon? && !content_is_a_specialist_document?
      end

      def content_tagged_to_a_finder?
        content_item.dig("links", "finder").present?
      end

      def content_tagged_to_mainstream_browse_pages?
        content_item.dig("links", "mainstream_browse_pages").present?
      end

      def content_has_curated_related_items?
        content_item.dig("links", "ordered_related_items").present? && content_item.dig("links", "parent").present?
      end

      def content_is_tagged_to_a_live_taxon?
        content_item.dig("links", "taxons").to_a.any? { |taxon| taxon["phase"] == "live" }
      end

      def content_is_a_specialist_document?
        content_item["schema_name"] == "specialist_document"
      end

      def content_is_a_html_publication?
        content_item["document_type"] == "html_publication"
      end

      def content_has_a_topic?
        content_item.dig("links", "topics").present?
      end

      def tagged_to_brexit?
        taxons = content_item.dig("links", "taxons").to_a
        brexit_taxon = "d6c2de5d-ef90-45d1-82d4-5f2438369eea"
        world_brexit_taxon = "d4c4d91d-fbe7-4eff-bd57-189138c626c9"

        taxons.each do |taxon|
          if taxon["content_id"].eql?(brexit_taxon) ||
              taxon["content_id"].eql?(world_brexit_taxon) ||
              taxon.dig("links", "parent_taxons").to_a.any? { |taxon_item| taxon_item["content_id"].eql?(brexit_taxon) }
            return true
          end
        end

        false
      end

      def show_brexit_cta?
        # If tagged directly to /brexit or /world/brexit
        # Or if tagged to a taxon which has /brexit as a parent
        # And is not the brexit checker start page
        brexit_start_page_content_id = "58d093a1-787d-4f36-a568-86da23a7b884"
        page_content_id = content_item["content_id"]
        tagged_to_brexit? && (page_content_id != brexit_start_page_content_id)
      end

      def step_by_step_count
        step_nav_helper.step_navs.count
      end

      def content_tagged_to_current_step_by_step?
        # TODO: remove indirection here
        step_nav_helper.show_header?
      end

      def content_tagged_to_a_reasonable_number_of_step_by_steps?
        step_nav_helper.show_related_links?
      end

      def content_tagged_to_other_step_by_steps?
        step_nav_helper.show_also_part_of_step_nav?
      end

      def breadcrumbs_based_on_ancestors
        ContentBreadcrumbsBasedOnAncestors.call(content_item)
      end

      def step_nav_helper
        @step_nav_helper ||= PageWithStepByStepNavigation.new(content_item, request_path, query_parameters)
      end

      def parent_finder
        @parent_finder ||= content_item.dig("links", "finder", 0)
      end
    end
  end
end