Restrict classes to the gem namespace

lib/sof-cycle.rb

@@ -12,5 +12,3 @@
 require_relative "sof/cycle"
 
 Dir[File.join(__dir__, "sof", "cycles", "*.rb")].each { |file| require file }
-
-require_relative "sof/time_span"

lib/sof/cycle.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
-require_relative "parser"
+require_relative "cycle/parser"
+require_relative "cycle/time_span"
 
 module SOF
   class Cycle

lib/sof/cycle/parser.rb

@@ -0,0 +1,108 @@
+# frozen_string_literal: true
+
+require "active_support/core_ext/hash/keys"
+require "active_support/core_ext/object/blank"
+require "active_support/core_ext/object/inclusion"
+require "active_support/core_ext/hash/reverse_merge"
+require "active_support/isolated_execution_state"
+
+module SOF
+  # This class is not intended to be referenced directly.
+  # This is an internal implementation of Cycle behavior.
+  class Cycle
+    class Parser
+      extend Forwardable
+      PARTS_REGEX = /
+        ^(?<vol>V(?<volume>\d*))? # optional volume
+        (?<set>(?<kind>L|C|W|E) # kind
+        (?<period_count>\d+) # period count
+        (?<period_key>D|W|M|Q|Y)?)? # period_key
+        (?<from>F(?<from_date>\d{4}-\d{2}-\d{2}))?$ # optional from
+      /ix
+
+      def self.dormant_capable_kinds = %w[E W]
+
+      def self.for(notation_or_parser)
+        return notation_or_parser if notation_or_parser.is_a? self
+
+        new(notation_or_parser)
+      end
+
+      def self.load(hash)
+        hash.symbolize_keys!
+        hash.reverse_merge!(volume: 1)
+        keys = %i[volume kind period_count period_key]
+        str = "V#{hash.values_at(*keys).join}"
+        return new(str) unless hash[:from_date]
+
+        new([str, "F#{hash[:from_date]}"].join)
+      end
+
+      def initialize(notation)
+        @notation = notation&.upcase
+        @match = @notation&.match(PARTS_REGEX)
+      end
+
+      attr_reader :match, :notation
+
+      delegate [:dormant_capable_kinds] => "self.class"
+      delegate [:period, :humanized_period] => :time_span
+
+      # Return a TimeSpan object for the period and period_count
+      def time_span
+        @time_span ||= TimeSpan.for(period_count, period_key)
+      end
+
+      def valid? = match.present?
+
+      def inspect = notation
+      alias_method :to_s, :inspect
+
+      def activated_notation(date)
+        return notation unless dormant_capable?
+
+        self.class.load(to_h.merge(from_date: date.to_date)).notation
+      end
+
+      def ==(other) = other.to_h == to_h
+
+      def to_h
+        {
+          volume:,
+          kind:,
+          period_count:,
+          period_key:,
+          from_date:
+        }
+      end
+
+      def parses?(notation_id) = kind == notation_id
+
+      def active? = !dormant?
+
+      def dormant? = dormant_capable? && from_date.nil?
+
+      def dormant_capable? = kind.in?(dormant_capable_kinds)
+
+      def period_count = match[:period_count]
+
+      def period_key = match[:period_key]
+
+      def vol = match[:vol] || "V1"
+
+      def volume = (match[:volume] || 1).to_i
+
+      def from_data
+        return {} unless from
+
+        {from: from}
+      end
+
+      def from_date = match[:from_date]
+
+      def from = match[:from]
+
+      def kind = match[:kind]
+    end
+  end
+end

lib/sof/cycle/time_span.rb

@@ -0,0 +1,232 @@
+# frozen_string_literal: true
+
+module SOF
+  # This class is not intended to be referenced directly.
+  # This is an internal implementation of Cycle behavior.
+  class Cycle
+    class TimeSpan
+      extend Forwardable
+      # TimeSpan objects map Cycle notations to behaviors for their periods
+      #
+      # For example:
+      #   'M' => TimeSpan::DatePeriod::Month
+      #   'Y' => TimeSpan::DatePeriod::Year
+      # Read each DatePeriod subclass for more information.
+      #
+      class InvalidPeriod < StandardError; end
+
+      class << self
+        # Return a time_span for the given count and period
+        def for(count, period)
+          case count.to_i
+          when 0
+            TimeSpanNothing
+          when 1
+            TimeSpanOne
+          else
+            self
+          end.new(count, period)
+        end
+
+        # Return a notation string from a hash
+        def notation(hash)
+          return unless hash.key?(:period)
+
+          [
+            hash.fetch(:period_count) { 1 },
+            notation_id_from_name(hash[:period])
+          ].compact.join
+        end
+
+        # Return the notation character for the given period name
+        def notation_id_from_name(name)
+          type = DatePeriod.types.find do |klass|
+            klass.period.to_s == name.to_s
+          end
+
+          raise InvalidPeriod, "'#{name}' is not a valid period" unless type
+
+          type.code
+        end
+      end
+
+      # Class used to calculate the windows of time so that
+      # a TimeSpan object will know the correct end of year,
+      # quarter, etc.
+      class DatePeriod
+        extend Forwardable
+        class << self
+          def for(count, period_notation)
+            @cached_periods ||= {}
+            @cached_periods[period_notation] ||= {}
+            @cached_periods[period_notation][count] ||= (for_notation(period_notation) || self).new(count)
+            @cached_periods[period_notation][count]
+          end
+
+          def for_notation(notation)
+            types.find do |klass|
+              klass.code == notation.to_s.upcase
+            end
+          end
+
+          def types = @types ||= Set.new
+
+          def inherited(klass)
+            DatePeriod.types << klass
+          end
+
+          @period = nil
+          @code = nil
+          @interval = nil
+          attr_reader :period, :code, :interval
+        end
+
+        delegate [:period, :code, :interval] => "self.class"
+
+        def initialize(count)
+          @count = count
+        end
+        attr_reader :count
+
+        def end_date(date)
+          @end_date ||= {}
+          @end_date[date] ||= date + duration
+        end
+
+        def begin_date(date)
+          @begin_date ||= {}
+          @begin_date[date] ||= date - duration
+        end
+
+        def duration = count.send(period)
+
+        def end_of_period(_) = nil
+
+        def humanized_period
+          return period if count == 1
+
+          "#{period}s"
+        end
+
+        class Year < self
+          @period = :year
+          @code = "Y"
+          @interval = "years"
+
+          def end_of_period(date)
+            date.end_of_year
+          end
+
+          def beginning_of_period(date)
+            date.beginning_of_year
+          end
+        end
+
+        class Quarter < self
+          @period = :quarter
+          @code = "Q"
+          @interval = "quarters"
+
+          def duration
+            (count * 3).months
+          end
+
+          def end_of_period(date)
+            date.end_of_quarter
+          end
+
+          def beginning_of_period(date)
+            date.beginning_of_quarter
+          end
+        end
+
+        class Month < self
+          @period = :month
+          @code = "M"
+          @interval = "months"
+
+          def end_of_period(date)
+            date.end_of_month
+          end
+
+          def beginning_of_period(date)
+            date.beginning_of_month
+          end
+        end
+
+        class Week < self
+          @period = :week
+          @code = "W"
+          @interval = "weeks"
+
+          def end_of_period(date)
+            date.end_of_week
+          end
+
+          def beginning_of_period(date)
+            date.beginning_of_week
+          end
+        end
+
+        class Day < self
+          @period = :day
+          @code = "D"
+          @interval = "days"
+
+          def end_of_period(date)
+            date
+          end
+
+          def beginning_of_period(date)
+            date
+          end
+        end
+      end
+      private_constant :DatePeriod
+
+      def initialize(count, period_id)
+        @count = Integer(count, exception: false)
+        @window = DatePeriod.for(period_count, period_id)
+      end
+      attr_reader :window
+
+      delegate [:end_date, :begin_date] => :window
+
+      def end_date_of_period(date)
+        window.end_of_period(date)
+      end
+
+      def begin_date_of_period(date)
+        window.beginning_of_period(date)
+      end
+
+      # Integer value for the period count or nil
+      def period_count
+        @count
+      end
+
+      delegate [:period, :duration, :interval, :humanized_period] => :window
+
+      # Return a date according to the rules of the time_span
+      def final_date(date)
+        return unless period
+
+        window.end_date(date.to_date)
+      end
+
+      def to_h
+        {
+          period:,
+          period_count:
+        }
+      end
+
+      class TimeSpanNothing < self
+      end
+
+      class TimeSpanOne < self
+        def interval = humanized_period
+      end
+    end
+  end
+end