sanger/sequencescape

# frozen_string_literal: true

# Handles display of plate template options (first page of cherrypicking)
# and the processing of any uploaded spreadsheets to set a layout
class PlateTemplateTask < Task
  # Class to extract the layout from an uploaded spreadsheet
  class SpreadsheetReader
    def initialize(csv_string, batch, plate_size)
      @csv_string = csv_string
      @requests = batch.requests.includes(asset: [:map, { plate: :barcodes }]).index_by(&:id)
      @plate_size = plate_size
    end

    # rubocop:todo Metrics/MethodLength
    def layout # rubocop:todo Metrics/AbcSize
      barcodes = Set.new
      plates =
        mapped_plate_wells.each_value.map do |mapped_wells|
          Array.new(plate_size) do |i|
            request_id = mapped_wells[i]
            if request_id.present?
              asset = requests[request_id].asset
              barcodes << asset.plate.barcode_number
              [request_id, asset.plate.barcode_number, asset.display_name]
            else
              CherrypickTask::EMPTY_WELL
            end
          end
        end

      [plates, barcodes.to_a]
    end

    # rubocop:enable Metrics/MethodLength

    private

    def mapped_plate_wells
      (Hash.new { |h, k| h[k] = {} }).tap do |parsed_plates|
        CSV.parse(csv_string, headers: :first_row) do |row|
          parse_spreadsheet_row(
            row['Request ID'],
            row['Plate'],
            row['Destination Well']
          ) { |plate_key, request_id, location| parsed_plates[plate_key][location.column_order] = request_id }
        end
      end
    end

    def parse_spreadsheet_row(request_id, plate_key, destination_well)
      return if request_id.blank? || request_id.to_i.zero?

      location = locations[destination_well] || return
      yield(plate_key.presence || 'default plate 1', request_id.to_i, location)
    end

    def locations
      @locations ||= Map.where(asset_size: plate_size).index_by(&:description)
    end

    attr_reader :requests, :plate_size, :csv_string
  end

  def partial
    'plate_template_batches'
  end

  # Returns a list of valid plate purpose types based on the requests in the current batch.
  def plate_purpose_options(batch)
    requests = batch.requests.flat_map(&:next_requests)
    plate_purposes = requests.filter_map(&:request_type).uniq.map(&:acceptable_purposes).flatten.uniq

    # Fallback situation for the moment
    plate_purposes = PlatePurpose.cherrypickable_as_target.all if plate_purposes.empty?
    plate_purposes.map { |p| [p.name, p.size, p.id] }.sort
  end

  def render_task(workflows_controller, params, _user)
    super
    workflows_controller.render_plate_template_task(self, params)
  end

  def do_task(workflows_controller, params, _user) # rubocop:todo Metrics/AbcSize
    return true if params[:file].blank?

    plate_size =
      if params[:plate_template].blank?
        PlatePurpose.find(params[:plate_purpose_id]).size
      else
        PlateTemplate.find(params[:plate_template]['0'].to_i).size
      end
    workflows_controller.spreadsheet_layout =
      SpreadsheetReader.new(params[:file].read, workflows_controller.batch, plate_size).layout
    true
  end
end