class Addressable::URI

def self.parse(uri)
  # If we were given nil, return nil.
  return nil unless uri
  # If a URI object is passed, just return itself.
  return uri.dup if uri.kind_of?(self)
  # If a URI object of the Ruby standard library variety is passed,
  # convert it to a string, then parse the string.
  # We do the check this way because we don't want to accidentally
  # cause a missing constant exception to be thrown.
  if uri.class.name =~ /^URI\b/
    uri = uri.to_s
  end
  # Otherwise, convert to a String
  begin
    uri = uri.to_str
  rescue TypeError, NoMethodError
    raise TypeError, "Can't convert #{uri.class} into String."
  end if not uri.is_a? String
  # This Regexp supplied as an example in RFC 3986, and it works great.
  scan = uri.scan(URIREGEX)
  fragments = scan[0]
  scheme = fragments[1]
  authority = fragments[3]
  path = fragments[4]
  query = fragments[6]
  fragment = fragments[8]
  user = nil
  password = nil
  host = nil
  port = nil
  if authority != nil
    # The Regexp above doesn't split apart the authority.
    userinfo = authority[/^([^\[\]]*)@/, 1]
    if userinfo != nil
      user = userinfo.strip[/^([^:]*):?/, 1]
      password = userinfo.strip[/:(.*)$/, 1]
    end
    host = authority.sub(
      /^([^\[\]]*)@/, EMPTY_STR
    ).sub(
      /:([^:@\[\]]*?)$/, EMPTY_STR
    )
    port = authority[/:([^:@\[\]]*?)$/, 1]
  end
  if port == EMPTY_STR
    port = nil
  end
  return new(
    :scheme => scheme,
    :user => user,
    :password => password,
    :host => host,
    :port => port,
    :path => path,
    :query => query,
    :fragment => fragment
  )
end