(defn signup-handler
  [req]
  (case (req :method)
    "GET"
      (do
      @{:status 200
        :headers (default-headers)
        :body (templates/render-signup (get-in req [:flash :signup] @{}))})
    "POST"
      (do
        (def formdata (or (httpkit/parse-www-form-urlencoded (req :body))
                          @{}))
        (def email (get formdata "email"))
        (def form-errors @{})

        (label _
          (when (or (nil? email) (empty? email))
            (put form-errors :email "email is required")
            (return _))

          (def activation-code (account/begin-signup email))
          (unless activation-code
            (put form-errors :email "account already exists")
            (return _))

          (mailer/send-signup-email email activation-code))

        (if (empty? form-errors)
          @{:status 200
            :headers (default-headers)
            :body (templates/render-action-result {:result "signup email sent" :next "/signup"})}
          (do
            (put (dyn :session) :flash {:signup { :form-errors form-errors }})
            @{:status 303
              :headers (merge-into (default-headers) {"Location" (req :path)})})))
    (bad-request)))