class Eco::API::UseCases::OozeSamples
  module HelpersMigration
    module Copying
      def session
        defined?(super)? super : @session
      end

      def logger
        session.logger
      end

      def copy_generic_paired_fields(src, dst, src_excluded: [], dst_excluded: [], exclude_ximport: false)
        HelpersMigration::TypedFieldsPairing.new(src, dst, src_excluded: src_excluded, dst_excluded: dst_excluded, exclude_ximport: false).tap do |pairing|
          pairing.each_pair do |src_fld, dst_fld|
            copy_field_content(src_fld, dst_fld)
            yield(src_fld, dst_fld, pairing) if block_given?
          end
        end
      end

      def copy_hooked_fields(src, dst, hook:, type:, fields_tracker: nil, src_excluded: [], dst_excluded: [])
        case hook
        when String
          with_src_dst_field_pair(src, dst, label: to_regex(hook), type: type, src_excluded: src_excluded, dst_excluded: dst_excluded) do |src_fld, dst_fld|
            copy_field_content(src_fld, dst_fld).tap do |result|
              fields_tracker.resolve(src_fld, dst_fld) if fields_tracker
              yield(src_fld, dst_fld, fields_tracker) if block_given?
            end
          end
        when Hash
          hook.each do |hook_src, hook_dst|
            src_lab, dst_lab = to_regex(hook_src), to_regex(hook_dst)
            with_src_dst_field_pair(src, dst, label: src_lab, label_dst: dst_lab, type: type, src_excluded: src_excluded, dst_excluded: dst_excluded) do |src_fld, dst_fld|
              copy_field_content(src_fld, dst_fld).tap do |result|
                fields_tracker.resolve(src_fld, dst_fld) if fields_tracker
                yield(src_fld, dst_fld, fields_tracker) if block_given?
              end
            end
          end
        end
      end

      def to_regex(str)
        /^#{str}$/i
      end

      # @note
      #   - When used with `type: nil` it may pair fields of different type. There isn't refinement for this yet.
      def with_src_dst_field_pair(src, dst, label: nil, label_dst: label, type: nil, src_excluded: [], dst_excluded: [])
        unless respond_to?(:with_fields, true)
          raise "These helpers are to be included in class cases inheriting from Eco::API::UseCases::OozeSamples::RegisterUpdateCase"
        end
        src_flds = with_fields(src, label: label, type: type)
        dst_flds = with_fields(dst, label: label_dst, type: type)
        src_fld, dst_fld = src_flds.first, dst_flds.first

        # Not found
        if dst_flds.empty? || src_flds.empty?
          msg = "There isn't a '#{type}'"
          dst_msg = dst_flds.empty?? "destination field named '#{label_dst}'" : nil
          src_msg = src_flds.empty?? "source field named '#{label}'" : nil
          msg << " #{[dst_msg, src_msg].join(" or ")} (source: '#{src.id}')"
          logger.warn(msg)
          return nil, nil
        end

        # Fields exclusion
        dst_flds -= dst_excluded unless dst_excluded.empty?
        src_flds -= src_excluded unless src_excluded.empty?
        src_fld, dst_fld = src_flds.first, dst_flds.first
        return src_fld, dst_fld if dst_flds.empty? || src_flds.empty?

        if dst_flds.count > 1
          logger.warn("There are #{dst_flds.count} destination '#{type}' fields named '#{label_dst}' (source: '#{dst.id}'). Using first...")
        end

        if src_flds.count > 1
          msg = "There are #{src_flds.count} source '#{type}' fields named '#{label}' (source: '#{src.id}'). "
          src_content = src_flds.reject(&:empty?)
          if src_content.empty?
            msg << "None with content. Using first..."
          else
            src_fld = src_content.first
            if src_content.count == 1
              msg << "Using the only one with content (idx: #{src_flds.index(src_fld)})..."
            else
              msg << "#{src_content.count} have content. Using first..."
            end
          end
          logger.warn(msg)
        end

        [src_fld, dst_fld].tap do |(src_fld, dst_fld)|
          yield(src_fld, dst_fld) if block_given?
        end
      end

      def copy_field_content(src, dst)
        type = src.type
        case type
        when "select"
          src.values.each {|val| dst.select(val)}
          dst.other_desc = src.other_desc if src.other && src.other_desc && dst.other
        when "plain_text", "date", "number", "gauge"
          dst.value = src.value
        when "rich_text"
          dst.content = src.content
        when "cross_reference"
          src.reference_ids.each {|id| dst.add(id)}
        when "people"
          dst.people_ids << src.people_ids.to_a
        when "geo"
          src_coo, dst_coo = src.coordinates, dst.coordinates
          dst_coo.lat, dst_coo.lon = src_coo.lat, src_coo.lon
        when "file"
          src.items.each do |src_item|
            dst.add_file(src_item.file_container_id) do |dst_item|
              dst_item.label = src_item.label
            end
          end
        when "image_gallery"
          src.images.each do |src_image|
            dst.add_image(src_image.upload_id) do |dst_image|
              dst_image.caption = src_image.caption
            end
          end
        when "checklist"
          src.items.each do |src_item|
            dst.add_item(label: src_item.label) do |dst_item|
              dst_item.checked = src_item.checked
            end
          end
        when "law"
          "won't copy"
        when "page_action"
          "won't copy"
        when "actions_list"
          "won't copy"
        when "signature"
          "can't copy"
        when "tag_field"
          "can't copy"
        when "chart"
          "won't copy"
        when "frequency_rate_chart"
          "won't copy"
        end
      end
    end
  end
end