rotational_array.rb in bluepill-0.0.3

- old
+ new

@@ -1,17 +1,21 @@
 module Bluepill
   module Util
    class RotationalArray < Array
      def initialize(size)
-       super
-       @index = 0
+       super(size)
+       
+       @capacity = size
+       @counter = 0
      end
      
      def push(value)
-       self[@index] = value
-       @index = (@index + 1) % self.size
-       puts @index
+       idx = rotational_idx(@counter)
+       self[idx] = value
+       
+       @counter += 1
+       self
      end
      
      alias_method :<<, :push
      
      def pop
@@ -25,10 +29,30 @@
      def unshift
        raise "Cannot call unshift on a rotational array"
      end
      
      def last
-       self[@index - 1]
+       return if @counter.zero?
+       
+       self[rotational_idx(@counter - 1)]
+     end
+     
+     def first
+       return if @counter.zero?
+       return self[0] if @counter <= @capacity
+       
+      self[rotational_idx(@counter)]
+     end
+     
+     def clear
+      @counter = 0
+      super
+     end
+     
+     private
+     
+     def rotational_idx(idx)
+       idx % @capacity
      end
    end
  end
 end