#lang racket

(provide client%)

(require (prefix-in net: "net.rkt")
         (prefix-in gmi: "gmi.rkt"))

(require net/url-string)

(define temporary-failures
  '((40 . "temporary failure")
    (41 . "server unavailable")
    (42 . "CGI error")
    (43 . "proxy error")
    (44 . "slow down")))

(define permanent-failures
  '((50 . "permanent failure")
    (51 . "not found")
    (52 . "gone")
    (53 . "proxy request refused")
    (59 . "bad request")))

(struct exn:status:input-required exn ()
  #:extra-constructor-name make-exn:status:input-required
  #:transparent)

(struct exn:status:redirect exn ()
  #:extra-constructor-name make-exn:status:redirect
  #:transparent)

(struct exn:status:temporary-failure exn (errno)
  #:extra-constructor-name make-exn:status:temporary-failure
  #:transparent)

(struct exn:status:permanent-failure exn (errno)
  #:extra-constructor-name make-exn:status:permanent-failure
  #:transparent)

(struct exn:status:certificate-required exn ()
  #:extra-constructor-name make-exn:status:certificate-required
  #:transparent)

(define client%
  (class object%
    (define document-object '())
    (define document-buffer '())
    (define current-url '())

    (super-new)

    (define/private (get-document url)
      (with-handlers
        ;; exceptions which may be raised by net:request
        ([exn:fail:network? (λ (exn) (displayln (exn-message exn)))]
         [net:exn:fail:response? (λ (exn) (displayln (exn-message exn)))])

        (let-values ([(status meta body-port) (net:request url)])
          (cond
            ;; clients MUST reject status codes outside of the 10-69 range
            [(or (< status 10) (> status 69))
             (void)]

            ;; 10-19 INPUT REQUIRED
            [(and (>= status 10) (<= status 19))
             (void)]

            ;; 20-29 SUCCESS
            [(and (>= status 20) (<= status 29))
             (void)]

            ;; 30-39 REDIRECT
            [(and (>= status 30) (<= status 39))
             (void)]

            ;; 40-49 TEMPORARY FAILURE
            [(and (>= status 40) (<= status 49))
             (void)]

            ;; 50-59 PERMANENT FAILURE
            [(and (>= status 50) (<= status 59))
             (void)]

            ;; 60-69 CERTIFICATE REQUIRED
            [(and (>= status 60) (<= status 69))]))))