add initial ToHashParser

lib/fog/parser.rb

@@ -24,3 +24,62 @@ module Fog
     end
   end
 end
+
+module Fog
+  class ToHashParser
+
+    def initialize
+      @stack = []
+    end
+
+    def characters(string)
+      @value ||= ''
+      @value << string.strip
+    end
+
+    def end_element(name)
+      @stack.pop
+      unless @value.empty?
+        @stack.last[name.to_sym] = @value
+        @value = ''
+      end
+    end
+
+    def body
+      @stack.first
+    end
+
+    def start_element(name, attributes = [])
+      @value = ''
+      parsed_attributes = {}
+      until attributes.empty?
+        if attributes.first.is_a?(Array)
+          key, value = attributes.shift
+        else
+          key, value = attributes.shift, attributes.shift
+        end
+        parsed_attributes[key.to_sym] = value
+      end
+      if @stack.last.is_a?(Array)
+        @stack.last << {name.to_sym => parsed_attributes}
+      else
+        data = if @stack.empty?
+          @stack.push(parsed_attributes)
+          parsed_attributes
+        elsif @stack.last[name.to_sym]
+          unless @stack.last[name.to_sym].is_a?(Array)
+            @stack.last[name.to_sym] = [@stack.last[name.to_sym]]
+          end
+          @stack.last[name.to_sym] << parsed_attributes
+          @stack.last[name.to_sym].last
+        else
+          @stack.last[name.to_sym] = {}
+          @stack.last[name.to_sym].merge!(parsed_attributes)
+          @stack.last[name.to_sym]
+        end
+        @stack.push(data)
+      end
+    end
+
+  end
+end