#lang racket

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

;; global state variable which will be an input port containing the
;; rendered out gemtext document as it shall be shown to the user
(define document-buffer null)

(define (go-cmd url)
  (if (non-empty-string? url)
      (let-values ([(status meta c-in) (net:get url)])
        (let-values ([(document) (gmi:parse (port->lines c-in))]
                     [(db-in db-out) (make-pipe #f)])

          (set! document-buffer db-in)
          (parameterize ([current-output-port db-out])
            (gmi:render document))

          (let ([remaining (pipe-content-length db-in)])
            (printf "document retrieved. ~a bytes\n" remaining))

          (next-cmd)))

      (displayln "go where?")))

(define (next-cmd)
  (define (iter depth)
    (when (> depth 0)
      (let ()
        (displayln (read-line document-buffer))
        (iter (sub1 depth)))))

  (iter 10)
  (newline)
  (let ([remaining (pipe-content-length document-buffer)])
     (printf "~a bytes remaining\n" remaining)))

(define (repl)
  (display "G-300 > ")

  (let ([matches (regexp-match #px"(\\w+)\\s*(.*)" (read-line))])
    (cond
      ;; nothing was given. default command
      [(not matches)
       (next-cmd)]

      ;; go command
      [(string=? (cadr matches) "go")
       (go-cmd (caddr matches))]))


  (repl))