require "date" class DateTime class << self # Returns Time.zone.now.to_datetime when Time.zone or # config.time_zone are set, otherwise returns # Time.now.to_datetime. def current ::Time.zone ? ::Time.zone.now.to_datetime : ::Time.now.to_datetime end end # Returns the number of seconds since 00:00:00. # # DateTime.new(2012, 8, 29, 0, 0, 0).seconds_since_midnight # => 0 # DateTime.new(2012, 8, 29, 12, 34, 56).seconds_since_midnight # => 45296 # DateTime.new(2012, 8, 29, 23, 59, 59).seconds_since_midnight # => 86399 def seconds_since_midnight sec + (min * 60) + (hour * 3600) end # Returns the number of seconds until 23:59:59. # # DateTime.new(2012, 8, 29, 0, 0, 0).seconds_until_end_of_day # => 86399 # DateTime.new(2012, 8, 29, 12, 34, 56).seconds_until_end_of_day # => 41103 # DateTime.new(2012, 8, 29, 23, 59, 59).seconds_until_end_of_day # => 0 def seconds_until_end_of_day end_of_day.to_i - to_i end # Returns the fraction of a second as a +Rational+ # # DateTime.new(2012, 8, 29, 0, 0, 0.5).subsec # => (1/2) def subsec sec_fraction end # Returns a new DateTime where one or more of the elements have been changed # according to the +options+ parameter. The time options (:hour, # :min, :sec) reset cascadingly, so if only the hour is # passed, then minute and sec is set to 0. If the hour and minute is passed, # then sec is set to 0. The +options+ parameter takes a hash with any of these # keys: :year, :month, :day, :hour, # :min, :sec, :offset, :start. # # DateTime.new(2012, 8, 29, 22, 35, 0).change(day: 1) # => DateTime.new(2012, 8, 1, 22, 35, 0) # DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1) # => DateTime.new(1981, 8, 1, 22, 35, 0) # DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => DateTime.new(1981, 8, 29, 0, 0, 0) def change(options) ::DateTime.civil( options.fetch(:year, year), options.fetch(:month, month), options.fetch(:day, day), options.fetch(:hour, hour), options.fetch(:min, options[:hour] ? 0 : min), options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec + sec_fraction), options.fetch(:offset, offset), options.fetch(:start, start) ) end # Uses Date to provide precise Time calculations for years, months, and days. # The +options+ parameter takes a hash with any of these keys: :years, # :months, :weeks, :days, :hours, # :minutes, :seconds. def advance(options) unless options[:weeks].nil? options[:weeks], partial_weeks = options[:weeks].divmod(1) options[:days] = options.fetch(:days, 0) + 7 * partial_weeks end unless options[:days].nil? options[:days], partial_days = options[:days].divmod(1) options[:hours] = options.fetch(:hours, 0) + 24 * partial_days end d = to_date.advance(options) datetime_advanced_by_date = change(year: d.year, month: d.month, day: d.day) seconds_to_advance = \ options.fetch(:seconds, 0) + options.fetch(:minutes, 0) * 60 + options.fetch(:hours, 0) * 3600 if seconds_to_advance.zero? datetime_advanced_by_date else datetime_advanced_by_date.since(seconds_to_advance) end end # Returns a new DateTime representing the time a number of seconds ago. # Do not use this method in combination with x.months, use months_ago instead! def ago(seconds) since(-seconds) end # Returns a new DateTime representing the time a number of seconds since the # instance time. Do not use this method in combination with x.months, use # months_since instead! def since(seconds) self + Rational(seconds.round, 86400) end alias :in :since # Returns a new DateTime representing the start of the day (0:00). def beginning_of_day change(hour: 0) end alias :midnight :beginning_of_day alias :at_midnight :beginning_of_day alias :at_beginning_of_day :beginning_of_day # Returns a new DateTime representing the middle of the day (12:00) def middle_of_day change(hour: 12) end alias :midday :middle_of_day alias :noon :middle_of_day alias :at_midday :middle_of_day alias :at_noon :middle_of_day alias :at_middle_of_day :middle_of_day # Returns a new DateTime representing the end of the day (23:59:59). def end_of_day change(hour: 23, min: 59, sec: 59) end alias :at_end_of_day :end_of_day # Returns a new DateTime representing the start of the hour (hh:00:00). def beginning_of_hour change(min: 0) end alias :at_beginning_of_hour :beginning_of_hour # Returns a new DateTime representing the end of the hour (hh:59:59). def end_of_hour change(min: 59, sec: 59) end alias :at_end_of_hour :end_of_hour # Returns a new DateTime representing the start of the minute (hh:mm:00). def beginning_of_minute change(sec: 0) end alias :at_beginning_of_minute :beginning_of_minute # Returns a new DateTime representing the end of the minute (hh:mm:59). def end_of_minute change(sec: 59) end alias :at_end_of_minute :end_of_minute # Returns a Time instance of the simultaneous time in the system timezone. def localtime(utc_offset = nil) utc = new_offset(0) Time.utc( utc.year, utc.month, utc.day, utc.hour, utc.min, utc.sec + utc.sec_fraction ).getlocal(utc_offset) end alias_method :getlocal, :localtime # Returns a Time instance of the simultaneous time in the UTC timezone. # # DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24)) # => Mon, 21 Feb 2005 10:11:12 -0600 # DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24)).utc # => Mon, 21 Feb 2005 16:11:12 UTC def utc utc = new_offset(0) Time.utc( utc.year, utc.month, utc.day, utc.hour, utc.min, utc.sec + utc.sec_fraction ) end alias_method :getgm, :utc alias_method :getutc, :utc alias_method :gmtime, :utc # Returns +true+ if offset == 0. def utc? offset == 0 end # Returns the offset value in seconds. def utc_offset (offset * 86400).to_i end # Layers additional behavior on DateTime#<=> so that Time and # ActiveSupport::TimeWithZone instances can be compared with a DateTime. def <=>(other) if other.respond_to? :to_datetime super other.to_datetime rescue nil else super end end end