(ns modern-cljs.procman
  (:require [cljs.core.async :as async
                             :refer [<! >! >!! <!! timeout chan take! put!]]
            [domina :as dom])
  (:require-macros
    [cljs.core.async.macros :refer [go]]))


(def c (chan))

(defn render [q]
  (apply str
    (for [p (reverse q)]
      (str "<div class='proc-" p "'>Process " p "</div>"))))


(defn peekn
  "Returns vector of (up to) n items from the end of vector v"
  [v n]
  (if (> (count v) n)
    (subvec v (- (count v) n))
    v))


(defn ^:export init []
  (when (and js/document
           (.-getElementById js/document)))

  (go (while true (<! (timeout 250)) (>! c 1)))
  (go (while true (<! (timeout 1000)) (>! c 2)))
  (go (while true (<! (timeout 1500)) (>! c 3)))
  (let [el (dom/by-id "other")
        out (dom/by-id "greeting")]
        (go (loop [q []]
            (dom/set-html! out (render q))
            (recur (-> (conj q (<! c)) (peekn 10)))))))