module NewspaperWorks
  module Ingest
    module NDNP
      class IssueIngester
        include NewspaperWorks::Logging
        include NewspaperWorks::Ingest::NDNP::NDNPAssetHelper
        include NewspaperWorks::Ingest::PubFinder

        attr_accessor :issue, :target, :opts

        delegate :path, to: :issue

        COPY_FIELDS = [
          :lccn,
          :edition_number,
          :edition_name,
          :volume,
          :publication_date,
          :held_by,
          :issue_number
        ].freeze

        # @param issue [NewspaperWorks::Ingest::NDNP::IssueIngest]
        #   source issue data
        # @param opts [Hash]
        #   ingest options, e.g. administrative metadata
        def initialize(issue, opts = {})
          @issue = issue
          @opts = opts
          @target = nil
          configure_logger('ingest')
        end

        def ingest
          construct_issue
          ingest_pages
          NewspaperWorks::ComposeIssuePDFJob.perform_later(@target)
        end

        def construct_issue
          create_issue
          find_or_create_linked_publication
        end

        def ingest_pages
          issue.each do |page|
            page_ingester(page).ingest
          end
        end

        private

          def page_ingester(page_data)
            NewspaperWorks::Ingest::NDNP::PageIngester.new(
              page_data,
              @target,
              @opts
            )
          end

          def publication_date
            parsed = DateTime.iso8601(issue.metadata.publication_date)
            parsed.strftime('%B %-d, %Y')
          end

          def publication_title(issue)
            issue.metadata.publication_title.strip.split(/ \(/)[0]
          end

          def issue_title
            "#{publication_title(issue)}: #{publication_date}"
          end

          def copy_issue_metadata
            metadata = issue.metadata
            # set (required, plural) title from single value obtained from reel:
            @target.title = [issue_title]
            # copy all fields with singular (non-repeatable) values on both
            #   target NewspaperIssue object, and metadata source:
            COPY_FIELDS.each do |fieldname|
              @target.send("#{fieldname}=", metadata.send(fieldname.to_s))
            end
          end

          def create_issue
            @target = NewspaperIssue.create
            copy_issue_metadata
            assign_administrative_metadata
            @target.save!
            write_log("Saved metadata to new NewspaperIssue #{@target.id}")
          end

          def find_or_create_linked_publication
            title = publication_title(issue)
            lccn = issue.metadata.lccn
            find_or_create_publication_for_issue(@target, lccn, title, @opts)
          end
      end
    end
  end
end