module SetecAstronomy
  module KeePass
    class GroupField
      FIELD_TYPES = [
        [0x0, 'ignored', :null],
        [0x1, 'groupid', :int],
        [0x2, 'group_name', :string],
        [0x3, 'creation_time', :date],
        [0x4, 'lastmod_time', :date],
        [0x5, 'lastacc_time', :date],
        [0x6, 'expire_time', :date],
        [0x7, 'imageid', :int],
        [0x8, 'level', :short],
        [0x9, 'flags', :int],
        [0xFFFF, 'terminator', :null]
      ]
      FIELD_TERMINATOR = 0xFFFF
      TYPE_CODE_FIELD_SIZE = 2   # unsigned short integer
      DATA_LENGTH_FIELD_SIZE = 4 # unsigned integer


      attr_reader :name, :data_type, :data

      def initialize(payload)
        type_code, @data_length = payload.read(TYPE_CODE_FIELD_SIZE + DATA_LENGTH_FIELD_SIZE).unpack('SI')
        @name, @data_type = _parse_type_code(type_code)
        @data = payload.read(@data_length)
      end

      def terminator?
        name == 'terminator'
      end

      def length
        TYPE_CODE_FIELD_SIZE + DATA_LENGTH_FIELD_SIZE + @data_length
      end

      def _parse_type_code(type_code)
        (_, name, data_type) = FIELD_TYPES.detect do |(code, *rest)|
          code == type_code
        end
        [name, data_type]
      end
    end
  end
end