require 'libxml'

module LibXML
  module XML
    module Conversions
      module Document
        def to_hash
          root.to_hash
        end
      end

      module Node
        CONTENT_ROOT = '__content__'

        def to_hash(hash={})
          if text?
            hash[CONTENT_ROOT] = content
          else
            hash[name] = sub_hash = {}
            attributes_to_hash(sub_hash)
            if array?
              children_array_to_hash(sub_hash)
            else
              children_to_hash(sub_hash)
            end
          end
          hash
        end

        protected

        def children_to_hash(hash={})
          each { |child| child.to_hash(hash) }
          hash
        end

        def attributes_to_hash(hash={})
          each_attr { |attr| hash[attr.name] = attr.value }
          hash
        end

        def children_array_to_hash(hash={})
          hash[child.name] = map do |child|
            returning({}) { |sub_hash| child.children_to_hash(sub_hash) }
          end
          hash
        end

        def array?
          child? && child.next? && child.name == child.next.name
        end
      end
    end
  end
end

LibXML::XML::Document.send(:include, LibXML::XML::Conversions::Document)
LibXML::XML::Node.send(:include, LibXML::XML::Conversions::Node)

module ActiveSupport
  module CoreExtensions
    module Hash
      module Conversions
        module ClassMethods
          # libxml
          def from_xml(xml)
            xml.gsub!(/\s*\n\s*/, '')
            typecast_xml_value(undasherize_keys(LibXML::XML::Parser.string(xml).parse.to_hash))
          end
        end
      end
    end
  end
end