#lang racket/base
;; Trivial example program demonstrating os2-udp.rkt.

(require racket/set)
(require racket/match)
(require "os2.rkt")
(require "os2-udp.rkt")
(require "os2-testing.rkt")

(define (packet-handler local-addr)
  (role (set (topic-publisher (udp-packet local-addr (wild) (wild)))
	     (topic-subscriber (udp-packet (wild) local-addr (wild))))
    [(udp-packet source _ #"quit\n")
     (list (send-message (udp-packet local-addr source #"OK, quitting\n"))
	   (kill #:reason "Asked to quit"))]
    [(udp-packet source sink body)
     (send-message (udp-packet sink source body))]))

(check-role (packet-handler (udp-listener 5555))
	    'arbitrary
	    (send-message (udp-packet (udp-address "127.0.0.1" 12345) (udp-listener 5555) #"abcd"))
	    'arbitrary
	    (send-message (udp-packet (udp-listener 5555) (udp-address "127.0.0.1" 12345) #"abcd")))

(define (main port)
  (ground-vm
   (transition 'none
     (spawn udp-spy)
     (spawn udp-driver)
     (spawn (transition 'none
	      (packet-handler (udp-listener port)))))))

(main 5999)