feat(packages): ludic.net - a party over UDP: peers, reliable ordered delivery, the hello's frame and the host's pids, join codes, room codes through a matchmaker with STUN, punching and a relay, the MTU cap and the wire codec; messages in on an inbox, the session's end and a silent guest as facts

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.net/room_tick.ludic

@@ -0,0 +1,106 @@
+# room_tick.ludic - the matchmaker's side of a frame: STUN asked three times, the room registered
+# or asked for, the host's look at who has asked, and a guest's switch to the relay
+function net__room_tick(dt: float) -> void {
+  if net__r_state == NET_R_IDLE or net__r_role == 0 { return }
+  net__r_t = net__r_t + dt
+  if net__r_state == NET_R_STUN {
+    net__room_stun_tick()
+    return
+  }
+  if net__r_state == NET_R_REGISTER or net__r_state == NET_R_ASK or (net__r_state == NET_R_ROOM and net__http != 0) {
+    net__room_answer()
+    return
+  }
+  if net__r_state == NET_R_DONE {
+    # four seconds and not one packet back from the host: through the relay instead (a slow
+    # welcome is not a closed router - anything heard means the direct path works)
+    let silent = net__peers[0].heard == net__dial_heard
+    let wait = net__conf().force_relay or (silent and net__r_t > 4.0)
+    if not net__via_relay and net__state == NET_JOINING and net__relay_ip != 0 and wait { net__use_relay() }
+    return
+  }
+  if net__r_state == NET_R_ROOM { net__room_watch(dt) }
+}
+
+# a second and a half for an answer, asked three times; without one, inside addresses only
+function net__room_stun_tick() -> void {
+  if net__pub_ip == 0 and net__r_t > 0.5 and net__r_tries < 3 {
+    net__r_tries += 1
+    net__r_t = 0.0
+    net__stun_send()
+    return
+  }
+  if net__pub_ip == 0 and net__r_tries < 3 { return }
+  let base = net__conf().signal_url
+  if net__r_role == 1 {
+    net__http = Http.post(`{base}/rooms`, net__room_body("host"))
+    net__r_state = NET_R_REGISTER
+  } else {
+    net__http = Http.post(`{base}/rooms/{net__room}/join`, net__room_body("pub"))
+    net__r_state = NET_R_ASK
+  }
+  net__r_t = 0.0
+}
+
+function net__room_answer() -> void {
+  let st = Http.poll(net__http)
+  if st < 0 {
+    if net__r_t > 12.0 {
+      Http.free(net__http)
+      net__http = 0
+      net__room_fail(NET_WHY_MATCHMAKER_SILENT)
+    }
+    return
+  }
+  var v: Val = null
+  if st > 0 and Http.ok(net__http) { v = Json.parse(Http.text(net__http)) }
+  Http.free(net__http)
+  net__http = 0
+  if net__r_state == NET_R_REGISTER {
+    let code = net__json_str(v, "code")
+    if len(code) == 0 {
+      net__room_fail(NET_WHY_NO_ROOM_GIVEN)
+      return
+    }
+    net__room = code
+    net__take_relay(v)
+    net__r_state = NET_R_ROOM
+    net__poll_t = 0.0
+    net__log(`room {code}`)
+    net__fact(NET_ROOM, -1, 0, 0, code)
+    return
+  }
+  if net__r_state == NET_R_ASK {
+    if v == null {
+      net__room_fail(NET_WHY_NO_ROOM)
+      return
+    }
+    net__take_relay(v)
+    net__room_connect(net__json_str(v, "host"), net__json_str(v, "local"))
+    return
+  }
+  # the host's look at the room
+  if v != null and value_has(v, "guests") != 0 {
+    let l = value_get(v, "guests")
+    for i in 0 .. value_count(l) {
+      let g = value_at(l, i)
+      net__new_guest(net__json_str(g, "pub"), net__json_str(g, "local"))
+    }
+  }
+}
+
+# the host, registered: its relay address kept fresh, new guests punched for, the room looked at
+function net__room_watch(dt: float) -> void {
+  net__relay_t = net__relay_t - dt
+  if net__relay_t < 0.0 and net__relay_ip != 0 {
+    net__relay_t = 3.0
+    net__relay_hello()
+  }
+  net__punch_tick(dt)
+  net__poll_t = net__poll_t - dt
+  if net__poll_t < 0.0 {
+    net__poll_t = 1.0
+    net__http = Http.get(`{net__conf().signal_url}/rooms/{net__room}`)
+    net__r_t = 0.0
+  }
+}