Module ActiveSupport::CoreExtensions::Time::Calculations

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 49
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 58
def ago(seconds)
  self.since(-seconds)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 145
def beginning_of_day
  (self - self.seconds_since_midnight).change(:usec => 0)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 153
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 168
def beginning_of_quarter
  beginning_of_month.change(:month => [10, 7, 4, 1].detect { |m| m <= self.month })
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 131
def beginning_of_week
  days_to_monday = self.wday!=0 ? self.wday-1 : 6
  (self - days_to_monday.days).midnight
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 174
def beginning_of_year
  change(:month => 1,:mday => 1,:hour => 0, :min => 0, :sec => 0, :usec => 0)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 34
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 160
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 121
def last_month
  months_ago(1)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 110
def last_year
  years_ago(1)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 73
def months_ago(months)
  months_since(-months)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 77
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 126
def next_month
  months_since(1)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 139
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 115
def next_year
  years_since(1)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 27
def seconds_since_midnight
  self.to_i - self.change(:hour => 0).to_i + (self.usec/1.0e+6)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 64
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

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 185
def tomorrow
  self.since(1.day)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 101
def years_ago(years)
  change(:year => self.year - years)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 105
def years_since(years)
  change(:year => self.year + years)
end

# File rails/activesupport/lib/active_support/core_ext/time/calculations.rb, line 180
def yesterday
  self.ago(1.day)
end