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diff --git a/src/midi.clj b/src/midi.clj
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+(ns midi
+  (:require [missionary.core :as m])
+  (:import [javax.sound.midi MidiSystem Receiver ShortMessage MidiDevice$Info MidiDevice Transmitter]))
+
+(def >midi-devices
+  (m/stream
+   (m/ap
+    (loop []
+      (m/amb= (MidiSystem/getMidiDeviceInfo)
+              (do
+                (m/? (m/sleep 5000))
+                (recur)))))))
+
+;; NOTE: Seems that there is a JVM bug that prevents device rescanning
+;;
+(def >midi-device-info
+  "A flow of maps of device name -> device properties"
+  (m/signal
+   (m/eduction (dedupe)
+               (m/ap (let [devices (m/?< >midi-devices)]
+                       (into {} (map (fn [^MidiDevice$Info d]
+                                       [(.getName d)
+                                        {:description (.getDescription d)
+                                         :vendor (.getVendor d)
+                                         :version (.getVersion d)
+                                         :device-info d}]) devices)))))))
+
+(defn >device-info
+  [device-name]
+  (m/ap (let [device-info (m/?< >midi-device-info)]
+          (get-in device-info [device-name :device-info]))))
+
+(defn >midi-messages
+  "A flow of java midi messages"
+  [^MidiDevice device]
+  (m/stream
+   (m/ap
+    (let [^Transmitter transmitter (m/? (m/via m/blk (.getTransmitter device)))
+          transmit (atom nil)
+          >transmit (m/eduction (filter some?) (m/watch transmit))
+          receiver (reify Receiver
+                     (send [_this midi-message _timestamp]
+                       (println "HI")
+                       (reset! transmit midi-message))
+                      ;; TODO: Close
+                     (close [this]))]
+      (try
+        (println "Connecting to transmitter")
+        (m/? (m/via m/blk (.setReceiver transmitter receiver)))
+        (println "Connected to transmitter")
+        (m/?< >transmit)
+        (finally
+          (println "Disconnecting from transmitter")
+          (m/? (m/compel (m/via m/blk (.close receiver))))
+          (println "Disconnected from transmitter")))))))
+
+(defn >device
+  "Returns a device for given device name. Returns nil if device not found."
+  [device-name with-device]
+  (m/ap
+    (when-let [device-info (m/?< (>device-info device-name))]
+      (let [^MidiDevice device (MidiSystem/getMidiDevice ^MidiDevice$Info device-info)]
+        ;; Essential problem: Combining taking element from flow to put in
+        ;; conditional, and cleaning up in catch.
+        ;; NOTE: You need the MidiDevice type hint when you call open and close!
+        (try
+          (println "Opening device")
+          (m/? (m/via m/blk (.open device)))
+          (println "Device opened")
+          (m/?< (with-device device))
+          (finally
+            (println "Closing device")
+            (m/compel (m/? (m/via m/blk (.close device))))
+            (println "Device closed")
+            ))))))
+
+(defn new-device
+  "Generate a new midi device.
+  Currently, this is a map of channel-num to [atom signal]."
+  []
+  (into {} (map (fn [i] [i (let [v (atom #{})] [v (m/signal (m/watch v))])]) (range 0 127))))
+
+(defn >midi-messages->ch-stream
+  [>midi-messages]
+  (m/signal
+   (m/ap
+    (let [device (new-device)]
+      (m/amb= device
+              (do
+                (let [v (m/?< >midi-messages)]
+                  (cond (instance? ShortMessage v)
+                        (let [channel (.getChannel ^ShortMessage v)
+                              command (.getCommand ^ShortMessage v)
+                              data-1 (.getData1 ^ShortMessage v)]
+                          (cond (= command ShortMessage/NOTE_ON)
+                                (swap! (first (get device channel)) conj data-1)
+                                (= command ShortMessage/NOTE_OFF)
+                                (swap! (first (get device channel)) disj data-1)))
+                        :else :other))
+                (m/amb)))))))
+
+(defn >ch-stream [>device ch]
+  (m/cp (m/?< (second (get >device ch)))))
+
+(def bus-sel (atom nil))
+(def >bus-sel (m/eduction (dedupe) (m/watch bus-sel)))
+(reset! bus-sel "Bus 1")
+#_(reset! bus-sel "Bus 2")
+#_(reset! bus-sel nil)
+
+(def run
+  (m/ap
+    (prn  (m/?< (>device (m/?< >bus-sel)
+                         (fn [v] (m/ap (m/amb  (m/?< v)))))))
+    ))
+
+(def close ((m/reduce prn {} run) {} {}))
+#_
+(close)
+
+;; OH! You hreally have to think about the supervision tree at all times
+;; It informs your function composition
+;;
+;;It helps to write in a continuation style - see `with-messages`
+;;>device is my most mature fn