class Nokogiri::HTML::SAX::ParserContext

def self.file filename, encoding
  ctx = LibXML.htmlCreateFileParserCtxt filename, encoding
  pc = allocate
  pc.cstruct = LibXML::XmlParserContext.new ctx
  pc
end

def self.memory data, encoding
  raise ArgumentError unless data
  raise "data cannot be empty" unless data.length > 0
  ctx = LibXML.htmlCreateMemoryParserCtxt data, data.length
  pc = allocate
  pc.cstruct = LibXML::XmlParserContext.new ctx
  if encoding
    enc = LibXML.xmlFindCharEncodingHandler(encoding)
    if !enc.null?
      LibXML.xmlSwitchToEncoding(ctx, enc)
    end
  end
  pc
end

def self.new thing, encoding = 'UTF-8'
  [:read, :close].all? { |x| thing.respond_to?(x) } ?  super :
    memory(thing, encoding)
end

def parse_with sax_handler, type = :html
  super
end