module Xmldsig
  class Transforms < Array

    def apply(node)
      @node = node
      each do |transform_node|
        @node = get_transform(@node, transform_node).transform
      end
      @node
    end

    private

    def get_transform(node, transform_node)
      case transform_node.get_attribute("Algorithm")
        when "http://www.w3.org/2000/09/xmldsig#enveloped-signature"
          Transforms::EnvelopedSignature.new(node, transform_node)
        when "http://www.w3.org/2001/10/xml-exc-c14n#",
            "http://www.w3.org/TR/2001/REC-xml-c14n-20010315",
            "http://www.w3.org/2006/12/xml-c14n11"
          Transforms::Canonicalize.new(node, transform_node)
        when "http://www.w3.org/2001/10/xml-exc-c14n#WithComments"
          Transforms::Canonicalize.new(node, transform_node, true)
        when "http://www.w3.org/TR/1999/REC-xpath-19991116"
          Transforms::XPath.new(node, transform_node)
      end
    end

  end
end