lib/timed/item.rb in timed-0.1.0 vs lib/timed/item.rb in timed-0.2.0

@@ -2,69 +2,64 @@
   # Item
   #
   # The Timed Item is a Moment that can be chained to others to form a sequence.
   # Importantly, items in a sequence are guaranteed to be sequential and non
   # overlapping.
-  
+
   class Item < Linked::Item
     include Moment
+
     # The value field is used to store the timespan and shuold not be accessed
     # directly.
 
     protected :value
     private :value=
 
+    # Provide a more ideomatic accessor for the sequence that the item is part
+    # of.
+
+    alias sequence list
+    alias in_sequence? in_list?
+
     # Creates a new Timed Item from a timespan. A timespan is any object that
     # responds to #begin and #end with two numerical values. Note that the end
     # must occur after the start for the span to be valid.
     #
     # If given a second argument, the two will instead be interpreted as the
     # begin and end time.
     #
     # timespan - object responding to #begin and #end.
     # end_at - if given, it togheter with the first argument will be used as the
-    #          begin and end time for the item
+    #          begin and end time for the item.
+    # sequence - optional sequence to add the item to.
 
-    def initialize(timespan, end_at = nil)
+    def initialize(timespan, end_at = nil, sequence: nil)
       if end_at
         begin_at = timespan
       else
         begin_at = timespan.begin
         end_at = timespan.end
       end
 
       raise TypeError unless begin_at.is_a?(Numeric) && end_at.is_a?(Numeric)
       raise ArgumentError if end_at < begin_at
 
-      super begin_at..end_at
+      super begin_at..end_at, list: sequence
     end
 
     # Returns the time when the item starts.
 
     def begin
-      value.begin
+      offset value.begin
     end
 
     # Returns the time when the item ends.
 
     def end
-      value.end
+      offset value.end
     end
 
-    # Returns a new Item in the intersection
-    #
-    # other - object that implements both #begin and #end.
-
-    def intersect(other)
-      begin_at = self.begin >= other.begin ? self.begin : other.begin
-      end_at = self.end <= other.end ? self.end : other.end
-
-      begin_at <= end_at ? self.class.new(begin_at, end_at) : nil
-    end
-
-    alias & intersect
-
     # Inserts an item after this one and before the next in the sequence. The
     # new item may not overlap with the two it sits between. A RuntimeError will
     # be raised if it does.
     #
     # If the given object is an Item it will be inserted directly. Otherwise, if
@@ -89,8 +84,12 @@
     def prepend(other)
       raise RuntimeError unless after? other
       raise RuntimeError unless first? || before?(previous)
 
       super
+    end
+
+    protected def offset(time)
+      in_sequence? ? sequence.offset(time) : time
     end
   end
 end