(defn- build-hsts-expire-header
  [{:keys [include-subdomains?] :or {include-subdomains? true}}]
  (str "max-age=" 0
       (if include-subdomains? "; includeSubDomains")))

(defn wrap-expire-hsts
  {:arglists '([handler] [handler options])}
  [handler & [{:as options}]]
  (fn [request]
    (-> (handler request)
        (resp/header "Strict-Transport-Security" (build-hsts-expire-header options)))))

(defn- http-url [url-string port]
  (let [url (java.net.URL. url-string)]
    (str (java.net.URL. "http" (.getHost url) (or port 80) (.getFile url)))))

(defn- get-request? [{method :request-method}]
  (or (= method :head)
      (= method :get)))

(defn wrap-insecure-redirect
  "Middleware that redirects any HTTPS request to the equivalent HTTP URL.
  Accepts the following options:
  :port - the port to use for redirects, defaults to 80."
  {:arglists '([handler] [handler options])}
  [handler & [{:keys [port]}]]
  (fn [request]
    (if (= (:scheme request) :https)
      (-> (resp/redirect (http-url (req/request-url request) port))
          (resp/status   (if (get-request? request) 301 307)))
      (handler request))))