# frozen_string_literal: true

module Asciidoctor
  module Epub3
    class SpineItemProcessor < Extensions::IncludeProcessor
      include ::Asciidoctor::Logging

      def initialize document
        @document = document
      end

      # NOTE only fires for includes in spine document if registered directly on the instance of the spine document
      def process doc, reader, target, _attributes
        spine_doc = doc
        # TODO: allow URI value
        unless ::File.file? (include_file = (spine_doc.normalize_system_path target, reader.dir, nil, target_name: 'include file'))
          logger.warn %(#{reader.line_info}: include file not found: #{include_file})
          return
        end
        inherited_attrs = spine_doc.attributes.dup
        # QUESTION should we keep backend-epub3 for convenience?
        %w(backend-epub3 backend-epub3-doctype-book docdir docfile docname doctitle outfilesuffix spine).each {|key| inherited_attrs.delete key }
        if (leveloffset = inherited_attrs['leveloffset'])
          leveloffset = inherited_attrs['leveloffset'] = %(#{leveloffset}@) unless leveloffset.end_with? '@'
        end

        # parse header to get author information
        spine_item_doc_meta = ::Asciidoctor.load_file include_file,
            safe: spine_doc.safe,
            backend: 'epub3-xhtml5',
            doctype: :article,
            parse_header_only: true,
            attributes: leveloffset ? { 'leveloffset' => leveloffset } : nil

        # blank out author information if present in sub-document
        # FIXME this is a huge hack...we need a cleaner way to do this; perhaps an API method that retrieves all the author attribute names
        if spine_item_doc_meta.attr? 'author'
          %w(author firstname lastname email authorinitials authors authorcount).each {|key| inherited_attrs.delete key }
          idx = 1
          while inherited_attrs.key? %(author_#{idx})
            %W[author_#{idx} firstname_#{idx} lastname_#{idx} email_#{idx} authorinitials_#{idx}].each {|key| inherited_attrs.delete key }
            idx += 1
          end
        end

        # REVIEW: reaching into converter to resolve document id feels like a hack; should happen in Asciidoctor parser
        # also, strange that "id" doesn't work here
        idprefix = (spine_doc.attr 'idprefix') || (spine_item_doc_meta.attr 'idprefix')
        idseparator = (spine_doc.attr 'idseparator') || (spine_item_doc_meta.attr 'idseparator')
        inherited_attrs['css-signature'] = DocumentIdGenerator.generate_id spine_item_doc_meta, idprefix, idseparator
        inherited_attrs['docreldir'] = ::File.dirname target

        # NOTE can't assign spine document as parent since there's too many assumptions in the Asciidoctor processor
        spine_item_doc = ::Asciidoctor.load_file include_file,
            # setting base_dir breaks if outdir is not a subdirectory of spine_doc.base_dir
            #base_dir: spine_doc.base_dir,
            # NOTE won't write to correct directory if safe mode is :secure
            safe: spine_doc.safe,
            backend: 'epub3-xhtml5',
            doctype: :article,
            header_footer: true,
            catalog_assets: true,
            attributes: inherited_attrs

        # restore attributes to those defined in the document header
        spine_item_doc.restore_attributes

        # FIXME: core should register document ID if specified
        unless (refs = spine_item_doc.references)[:ids].include? spine_item_doc.id
          spine_item_doc.register :ids, [spine_item_doc.id, (spine_item_doc.attr 'docreftext') || spine_item_doc.doctitle]
        end

        refs[:spine] = spine_doc
        refs[:spine_items] = ((spine_doc.references[:spine_items] ||= []) << spine_item_doc)
        # NOTE if there are attribute assignments between the include directives,
        # then this ordered list is not continguous, so bailing on the idea
        #reader.replace_line %(. link:#{::File.basename(spine_item_doc.attr 'outfile')}[#{spine_item_doc.doctitle}])
        nil
      end

      # handles? should get the attributes on include directive as the second argument
      def handles? target
        (@document.attr? 'spine') && (ASCIIDOC_EXTENSIONS.include? ::File.extname(target))
      end

      # FIXME: this method shouldn't be required
      def update_config config
        (@config ||= {}).update config
      end
    end
  end
end