module ActiveSupport #:nodoc: module CoreExtensions #:nodoc: module Time #:nodoc: # Enables the use of time calculations within Time itself module Calculations def self.included(base) #:nodoc: base.extend(ClassMethods) end module ClassMethods # Return the number of days in the given month. If a year is given, # February will return the correct number of days for leap years. # Otherwise, this method will always report February as having 28 # days. def days_in_month(month, year=nil) if month == 2 !year.nil? && (year % 4 == 0) && ((year % 100 != 0) || (year % 400 == 0)) ? 29 : 28 elsif month <= 7 month % 2 == 0 ? 30 : 31 else month % 2 == 0 ? 31 : 30 end end end # Seconds since midnight: Time.now.seconds_since_midnight def seconds_since_midnight self.to_i - self.change(:hour => 0).to_i + (self.usec/1.0e+6) end # Returns a new Time where one or more of the elements have been changed according to the +options+ parameter. The time options # (hour, minute, sec, usec) reset cascadingly, so if only the hour is passed, then minute, sec, and usec is set to 0. If the hour and # minute is passed, then sec and usec is set to 0. def change(options) ::Time.send( self.utc? ? :utc : :local, options[:year] || self.year, options[:month] || self.month, options[:mday] || self.mday, options[:hour] || self.hour, options[:min] || (options[:hour] ? 0 : self.min), options[:sec] || ((options[:hour] || options[:min]) ? 0 : self.sec), options[:usec] || ((options[:hour] || options[:min] || options[:sec]) ? 0 : self.usec) ) end # Uses Date to provide precise Time calculations for years, months, and days. The +options+ parameter takes a hash with # any of these keys: :months, :days, :years. def advance(options) d = ::Date.new(year + (options.delete(:years) || 0), month, day) d = d >> options.delete(:months) if options[:months] d = d + options.delete(:days) if options[:days] change(options.merge(:year => d.year, :month => d.month, :mday => d.day)) end # Returns a new Time representing the time a number of seconds ago, this is basically a wrapper around the Numeric extension # Do not use this method in combination with x.months, use months_ago instead! def ago(seconds) self.since(-seconds) end # Returns a new Time representing the time a number of seconds since the instance time, this is basically a wrapper around #the Numeric extension. Do not use this method in combination with x.months, use months_since instead! def since(seconds) initial_dst = self.dst? ? 1 : 0 f = seconds.since(self) final_dst = f.dst? ? 1 : 0 (seconds.abs >= 86400 && initial_dst != final_dst) ? f + (initial_dst - final_dst).hours : f end alias :in :since # Returns a new Time representing the time a number of specified months ago def months_ago(months) months_since(-months) end def months_since(months) year, month, mday = self.year, self.month, self.mday month += months # in case months is negative while month < 1 month += 12 year -= 1 end # in case months is positive while month > 12 month -= 12 year += 1 end max = ::Time.days_in_month(month, year) mday = max if mday > max change(:year => year, :month => month, :mday => mday) end # Returns a new Time representing the time a number of specified years ago def years_ago(years) change(:year => self.year - years) end def years_since(years) change(:year => self.year + years) end # Short-hand for years_ago(1) def last_year years_ago(1) end # Short-hand for years_since(1) def next_year years_since(1) end # Short-hand for months_ago(1) def last_month months_ago(1) end # Short-hand for months_since(1) def next_month months_since(1) end # Returns a new Time representing the "start" of this week (Monday, 0:00) def beginning_of_week days_to_monday = self.wday!=0 ? self.wday-1 : 6 (self - days_to_monday.days).midnight end alias :monday :beginning_of_week alias :at_beginning_of_week :beginning_of_week # Returns a new Time representing the start of the given day in next week (default is Monday). def next_week(day = :monday) days_into_week = { :monday => 0, :tuesday => 1, :wednesday => 2, :thursday => 3, :friday => 4, :saturday => 5, :sunday => 6} since(1.week).beginning_of_week.since(days_into_week[day].day).change(:hour => 0) end # Returns a new Time representing the start of the day (0:00) def beginning_of_day (self - self.seconds_since_midnight).change(:usec => 0) end alias :midnight :beginning_of_day alias :at_midnight :beginning_of_day alias :at_beginning_of_day :beginning_of_day # Returns a new Time representing the start of the month (1st of the month, 0:00) def beginning_of_month #self - ((self.mday-1).days + self.seconds_since_midnight) change(:mday => 1,:hour => 0, :min => 0, :sec => 0, :usec => 0) end alias :at_beginning_of_month :beginning_of_month # Returns a new Time representing the end of the month (last day of the month, 0:00) def end_of_month #self - ((self.mday-1).days + self.seconds_since_midnight) last_day = ::Time.days_in_month( self.month, self.year ) change(:mday => last_day,:hour => 0, :min => 0, :sec => 0, :usec => 0) end alias :at_end_of_month :end_of_month # Returns a new Time representing the start of the quarter (1st of january, april, july, october, 0:00) def beginning_of_quarter beginning_of_month.change(:month => [10, 7, 4, 1].detect { |m| m <= self.month }) end alias :at_beginning_of_quarter :beginning_of_quarter # Returns a new Time representing the start of the year (1st of january, 0:00) def beginning_of_year change(:month => 1,:mday => 1,:hour => 0, :min => 0, :sec => 0, :usec => 0) end alias :at_beginning_of_year :beginning_of_year # Convenience method which returns a new Time representing the time 1 day ago def yesterday self.ago(1.day) end # Convenience method which returns a new Time representing the time 1 day since the instance time def tomorrow self.since(1.day) end end end end end