lots of changes

lib/time_ext/time.rb

@@ -1,5 +1,13 @@
 class Time
   
+  def days_into_week
+    defined?(DAYS_INTO_WEEK) ? DAYS_INTO_WEEK : { :monday => 0, :tuesday => 1, :wednesday => 2, :thursday => 3, :friday => 4, :saturday => 5, :sunday => 6 }
+  end
+  
+  def common_year_days_in_month
+    defined?(COMMON_YEAR_DAYS_IN_MONTH) ? COMMON_YEAR_DAYS_IN_MONTH : [nil, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+  end
+  
   # Returns a new Time representing the start of the unit specified (second by default)
   def floor(unit = :sec)
     self.send("beginning_of_#{unit}")
@@ -14,6 +22,13 @@ class Time
   alias :beginning_of_next :ceil
   alias :at_beginning_of_next :ceil
   
+  def round(unit = :sec)
+    next_unit = self.ceil(unit)
+    this_unit = self.floor(unit)
+    (self - this_unit) < (next_unit - self) ? this_unit : next_unit
+  end
+  alias :beginning_of_closest :round
+  
   # Short-hand for seconds_ago(1)
   def prev_second
     ago(1)
@@ -58,6 +73,21 @@ class Time
     days_since(1)
   end
   
+  # Returns a new Time representing the start of the given day in the previous week (default is Monday).
+  def prev_week(day = :monday)
+    weeks_ago(1).beginning_of_week.since(days_into_week[day].day).change(:hour => 0)
+  end
+  
+  # Short-hand for quarters_since(1).beginning_of_quarter
+  def next_quarter
+    quarters_since(1).beginning_of_quarter
+  end
+  
+  # Short-hand for quarters_ago(1).beginning_of_quarter
+  def prev_quarter
+    quarters_ago(1).beginning_of_quarter
+  end
+  
   # Aliases to keep available method names to a standard pattern
   alias :secs_ago :ago
   alias :seconds_ago :ago
@@ -66,34 +96,54 @@ class Time
   
   # Returns a new Time representing the time a number of specified minutes ago
   def minutes_ago(minutes)
-    advance(:minutes => -minutes)
+    ago(minutes.minutes)
   end
   alias :mins_ago :minutes_ago
   
   # Returns a new Time representing the time a number of specified minutes in the future
   def minutes_since(minutes)
-    advance(:minutes => minutes)
+    since(minutes.minutes)
   end
   alias :mins_since :minutes_since
   
   # Returns a new Time representing the time a number of specified hours ago
   def hours_ago(hours)
-    advance(:hours => -hours)
+    ago(hours.hours)
   end
   
   # Returns a new Time representing the time a number of specified hours in the future
   def hours_since(hours)
-    advance(:hours => hours)
+    since(hours.hours)
   end
   
   # Returns a new Time representing the time a number of specified days ago
   def days_ago(days)
-    advance(:days => -days)
+    ago(days.days)
   end
   
   # Returns a new Time representing the time a number of specified days in the future
   def days_since(days)
-    advance(:days => days)
+    since(days.days)
+  end
+  
+  # Returns a new Time representing the time a number of specified weeks ago
+  def weeks_ago(weeks)
+    ago(weeks.weeks)
+  end
+  
+  # Returns a new Time representing the time a number of specified weeks in the future
+  def weeks_since(weeks)
+    since(weeks.weeks)
+  end
+  
+  # Returns a new Time representing the time a number of specified quarters (3 months) ago
+  def quarters_ago(quarters)
+    ago((quarters * 3).months)
+  end
+  
+  # Returns a new Time representing the time a number of specified quarters (3 months) in the future
+  def quarters_since(quarters)
+    since((quarters * 3).months)
   end
   
   # Returns a new Time representing the start of the second, XX:XX:XX.000000 (.000000000 in ruby1.9)