module Voyager
  class Status
    attr_reader :statuses
    
    def initialize(holdings)
      @statuses = parse_holdings_status(holdings)
    end
    
    def to_hash(args = {})
      @statuses
    end
    
    private
    
    def parse_holdings_status(holdings)
      status_hash = combine_statuses(holdings)
      holdings_hash = {}
      status_hash.each_pair { |mfhdid,items| holdings_hash[mfhdid.to_s] = determine_status(items) }
      holdings_hash
    end
    
    def combine_statuses(holdings)
      
      statuses = {}
      
      # for each holding, for each item create an array of status codes
      # we don't need bibid becasue each Collection call processes one bib
      holdings.each do |holding|
        bibid, mfhdid, itemid, status = holding.values
        unless itemid.nil?
          statuses[mfhdid] ||= {}
          statuses[mfhdid][itemid] ||= []
          statuses[mfhdid][itemid] << status
        else
          statuses[mfhdid] = {'no_items' => []}
        end
      end
      statuses
    end

    # 1 Not Charged
    # 2 Charged
    # 3 Renewed
    # 4 Overdue
    # 5 Recall Request
    # 6 Hold Request
    # 7 On Hold
    # 8 In Transit
    # 9 In Transit Discharged           no longer used but appear in records
    # 10  In Transit On Hold            no longer used but appear in records
    # 11  Discharged
    # 12  Missing
    # 13  Lost--Library Applied
    # 14  Lost--System Applied
    # 15  Claims Returned               x
    # 16  Damaged                       x
    # 17  Withdrawn                     skip item
    # 18  At Bindery
    # 19  Cataloging Review             x
    # 20  Circulation Review            x
    # 21  Scheduled
    # 22  In Process
    # 23  Call Slip Request
    # 24  Short Loan Request
    # 25  Remote Storage Request
    
    def determine_status(items)
      
      return 'none' if items.has_key?('no_items')

      icnt = 0  # count of items
      ucnt = 0  # count of unavailable items
      
      items.each_pair do |itemid,statuses|
        # skip withdrawn
        unless statuses.include?(17)
          icnt += 1
          # the overwhelming majority of items have only one status
          if statuses.length == 1
            ucnt += 1 unless [1,9,11].any? {|code| statuses.include?(code)}
          else
            # some unavalable statuses can be in combination with 1, 9 and 11 so we test for them first
            if [2,3,4,5,6,7,8,10,12,13,14,18,21,22,23,24,25].any? {|code| statuses.include?(code)}
              ucnt += 1
            end
          end
        end
      end
      
      return 'none' if icnt == 0
      return 'available' if ucnt == 0
      return 'unavailable' if icnt == ucnt
      return 'some_available'

    end
    
  end
end