module OEmbed::HttpHelper

def http_get(uri, options = {})
  found = false
  remaining_redirects = options[:max_redirects] ? options[:max_redirects].to_i : 4
  until found
    http = Net::HTTP.new(uri.host, uri.port)
    http.use_ssl = uri.scheme == 'https'
    http.verify_mode = OpenSSL::SSL::VERIFY_PEER
    http.read_timeout = http.open_timeout = options[:timeout] if options[:timeout]
    methods = if RUBY_VERSION < "2.2"
        %w{scheme userinfo host port registry}
    else
        %w{scheme userinfo host port}
    end
    methods.each { |method| uri.send("#{method}=", nil) }
    req = Net::HTTP::Get.new(uri.to_s)
    req['User-Agent'] = "Mozilla/5.0 (compatible; ruby-oembed/#{OEmbed::VERSION})"
    res = http.request(req)
    if remaining_redirects == 0
      found = true
    elsif res.is_a?(Net::HTTPRedirection) && res.header['location']
      uri = URI.parse(res.header['location'])
      remaining_redirects -= 1
    else
      found = true
    end
  end
  case res
  when Net::HTTPNotImplemented
    raise OEmbed::UnknownFormat
  when Net::HTTPNotFound
    raise OEmbed::NotFound, uri
  when Net::HTTPSuccess
    res.body
  else
    raise OEmbed::UnknownResponse, res && res.respond_to?(:code) ? res.code : 'Error'
  end
rescue StandardError
  # Convert known errors into OEmbed::UnknownResponse for easy catching
  # up the line. This is important if given a URL that doesn't support
  # OEmbed. The following are known errors:
  # * Net::* errors like Net::HTTPBadResponse
  # * JSON::JSONError errors like JSON::ParserError
  if defined?(::JSON) && $!.is_a?(::JSON::JSONError) || $!.class.to_s =~ /\ANet::/
    raise OEmbed::UnknownResponse, res && res.respond_to?(:code) ? res.code : 'Error'
  else
    raise $!
  end
end