Prepare for talk

3 files changed, 161 insertions, 33 deletions

diff --git a/dev/scratch.clj b/dev/scratch.clj
index 0115233..315df29 100644
--- a/dev/scratch.clj
+++ b/dev/scratch.clj
@@ -4,7 +4,8 @@
             [unheard.instrument.minilab3 :as minilab3]
             [unheard.instrument.omx-27 :as omx-27]
             [unheard.theory :refer [note poly]]
-            [missionary.core :as m]))
+            [missionary.core :as m])
+  (:import [javax.sound.midi ShortMessage]))
 
 #_(print-all-midi-devices)
 
@@ -22,6 +23,7 @@
   (poly
    (triad clock tonic)
 
+   #_
    (triad clock (m/latest #(+ % 12) tonic))
 
    ;; The rest of the "song" is a drum pattern.
@@ -64,7 +66,5 @@
                        p (song song-config)]
                    (m/?< (m/latest vector clock p))))))))
 
-#_(def cancel
-    (run prn prn))
 
-#_(cancel)
+(def cancel (run {} {}))
diff --git a/src/unheard/instrument/omx_27.clj b/src/unheard/instrument/omx_27.clj
index 33c18c8..ab3f28d 100644
--- a/src/unheard/instrument/omx_27.clj
+++ b/src/unheard/instrument/omx_27.clj
@@ -2,7 +2,8 @@
   (:require [unheard.instrument.util :refer [matching-control]]))
 
 (def device-name "CoreMIDI4J - omx-27")
-(def omx-27
+
+(def config
   {:knob
    {1 (matching-control 0 0 21)
     2 (matching-control 0 0 22)
diff --git a/src/unheard/midi.clj b/src/unheard/midi.clj
index b9f20c4..d47e5b1 100644
--- a/src/unheard/midi.clj
+++ b/src/unheard/midi.clj
@@ -2,11 +2,34 @@
   (:require [missionary.core :as m]
             [taoensso.trove :as log])
   (:import [javax.sound.midi MidiSystem Receiver ShortMessage MidiDevice$Info MidiDevice Transmitter MidiMessage]
-           [uk.co.xfactorylibrarians.coremidi4j CoreMidiDeviceProvider]))
+           [uk.co.xfactorylibrarians.coremidi4j CoreMidiDeviceProvider CoreMidiNotification]))
 
 (defn get-all-midi-device-info []
   (CoreMidiDeviceProvider/getMidiDeviceInfo))
 
+(def device-infos
+  "A publisher containing the latest result of MidiSystem#getMidiDeviceInfo."
+  (m/signal
+   (m/cp
+    (m/?<
+     (m/ap
+        ;; TODO: getMidiDeviceInfo could theoretically block
+        ;; Move to m/blk
+      (let [devices (atom (CoreMidiDeviceProvider/getMidiDeviceInfo))
+            >devices (m/watch devices)
+            notification-listener
+            (reify CoreMidiNotification
+              (midiSystemUpdated [_this]
+                (reset! devices (CoreMidiDeviceProvider/getMidiDeviceInfo))))]
+        (m/amb=
+         (do
+           (m/? (m/via m/blk (CoreMidiDeviceProvider/addNotificationListener notification-listener)))
+           (m/amb))
+         (m/?< >devices)
+         (try (m/? m/never)
+              (finally
+                (m/? (m/via m/blk (CoreMidiDeviceProvider/removeNotificationListener notification-listener))))))))))))
+
 ;; Move to tools.repl
 (defn print-all-midi-devices
   "Prints the names of all MIDI devices attached to the computer."
@@ -14,6 +37,9 @@
   (doseq [^MidiDevice$Info device-info (get-all-midi-device-info)]
     (println (.getName device-info))))
 
+(comment
+  (print-all-midi-devices))
+
 (defn select-devices
   "Given device info list `devices`, return seq where device name is `device-name`.
   If tx? is true, returned devices will have unlimited transmitters.
@@ -81,15 +107,15 @@
        (m/?
         (t (m/stream
             (m/ap
-              (loop []
-                (m/amb
-                 (do
-                   (log/log! {:level :debug, :id :midi/tx-awaiting-value})
-                   (m/amb))
-                 (let [v (m/? rv)]
-                   (log/log! {:level :debug, :id :midi/tx-received-value, :data {:value (str v)}})
-                   v)
-                 (recur)))))))
+             (loop []
+               (m/amb
+                (do
+                  (log/log! {:level :debug, :id :midi/tx-awaiting-value})
+                  (m/amb))
+                (let [v (m/? rv)]
+                  (log/log! {:level :debug, :id :midi/tx-received-value, :data {:value (str v)}})
+                  v)
+                (recur)))))))
        (finally
          (log/log! {:level :info, :id :midi/closing-tx})
          (m/? (m/via m/blk (.close transmitter)))
@@ -130,14 +156,18 @@
   "Opens device named `name`.
 
   Device will consume `flow`, a flow of Message objects."
-  [name flow]
-  (let [device
-        (first
-         (select-devices (get-all-midi-device-info)
-                         name false true))]
-    (with-device device
-      (fn [d]
-        (with-rx d flow)))))
+  [>name flow]
+  (m/ap
+   (let [device
+         (first
+          (select-devices (get-all-midi-device-info)
+                          (m/?< name) false true))]
+     (if device
+       (m/?
+        (with-device device
+          (fn [d]
+            (with-rx d flow))))
+       (m/amb)))))
 
 (defn <bus
   "Opens device named `name`.
@@ -145,17 +175,24 @@
   Calls `flow-handler` with a flow of midi messages.
 
   `flow-handler` should return a flow."
-  [name flow-handler]
-  (let [device
-        (first
-         (select-devices (get-all-midi-device-info)
-                         name true false))]
-    (with-device device
-      (fn [d]
-        (with-tx d
-          (fn [f]
-            (m/reduce prn nil (flow-handler f))))))))
+  [>name flow-handler]
+  (m/ap
+   (try
+     (let [device
+           (first
+            (select-devices (get-all-midi-device-info)
+                            (m/?< >name) true false))]
+       (if device
+         (m/?
+          (with-device device
+            (fn [d]
+              (with-tx d
+                (fn [f]
+                  (m/reduce prn nil (flow-handler f)))))))
+         (m/amb)))
+     (catch missionary.Cancelled _ (m/amb)))))
 
+;; TODO: Move elsewhere
 (defn echo
   "Echo test."
   [name from-ch to-ch]
@@ -209,3 +246,93 @@
         (map (fn [[group instance]]
                {group (into {} (map (fn [[id flow]] {id (flow f)}) instance))})
              config)))
+
+;; TODO git-bug c947320
+(def short-message->notes
+  "A transducer filtering ShortMessages down to note messages, and returning
+  a set of active notes."
+  (fn [rf]
+    (let [prev (volatile! nil)]
+      (fn
+        ([] (rf))
+        ([result] (rf result))
+        ([result ^ShortMessage input]
+         (let [command (.getCommand input)]
+           (cond
+             ;; Channel Mode Message "All notes off"
+             (and (= ShortMessage/CONTROL_CHANGE command)
+                  (= 123 (.getData1 input))
+                  (= 0 (.getData2 input)))
+             (do
+               (vreset! prev #{})
+               (rf result #{}))
+             (= ShortMessage/NOTE_ON command)
+             (let [prev-v @prev
+                   next (conj (into #{} prev-v) (.getData1 input))]
+               (vreset! prev next)
+               (rf result next))
+             (= ShortMessage/NOTE_OFF command)
+             (let [prev-v @prev
+                   next (disj (into #{} prev-v) (.getData1 input))]
+               (vreset! prev next)
+               (rf result next))
+             :else
+             result)))))))
+
+(defn test-msg [cmd ch d1 d2]
+  (ShortMessage. cmd ch d1 d2))
+
+(comment
+  (into []
+        (transduce
+         short-message->notes
+         conj
+         []
+         (conj
+          (map (fn [[cmd d1]] (test-msg cmd 0 d1 9))
+               [[ShortMessage/NOTE_ON 1]
+                [ShortMessage/CONTROL_CHANGE 1]
+                [ShortMessage/NOTE_ON 2]
+                [ShortMessage/NOTE_OFF 2]
+                [ShortMessage/NOTE_OFF 1]])))))
+
+;; TODO: Move this logic into bus fn
+(defn short-messages
+  [>device-name]
+  (m/stream
+   (m/ap
+    (let [short-messages (atom nil)
+          >short-messages (m/watch short-messages)]
+      (m/amb=
+       (do (reset! short-messages nil)
+           (m/?
+            (<bus >device-name
+                  (fn [v]
+                    (m/ap
+                     (try (let [msg (m/?< v)]
+                            (reset! short-messages msg))
+                          (catch missionary.Cancelled c
+                          ;; When the upstream flow is cancelled, we emit "All notes off" to consumers
+                            (doseq [ch (range 0 16)]
+                              (reset! short-messages (ShortMessage. ShortMessage/CONTROL_CHANGE ch 123 0)))
+                            (throw c))))))))
+       (if-let [m (m/?< >short-messages)]
+         m
+         (m/amb)))))))
+
+(defn notes [short-messages]
+  (m/signal
+   (m/cp
+    (m/?<
+     (m/ap
+      (m/amb= #{}
+              (m/?< (m/eduction short-message->notes short-messages))))))))
+
+(comment
+  (def dn (atom "CoreMIDI4J - Minilab3 MIDI"))
+  (def >dn (m/watch dn))
+
+  (def cancel ((m/reduce prn nil (notes (short-messages >dn))) prn prn))
+  (reset! dn "CoreMIDI4J - IAC Bus")
+  (reset! dn nil)
+  (cancel))