Listen to midi

src/jsMain/kotlin/nl/astraeus/vst/chip/midi/Midi.kt

@@ -0,0 +1,89 @@
+package nl.astraeus.vst.chip.midi
+
+import kotlinx.browser.window
+import nl.astraeus.vst.chip.audio.VstChipWorklet
+import nl.astraeus.vst.chip.view.MainView
+
+external class MIDIInput {
+  val connection: String
+  val id: String
+  val manufacturer: String
+  val name: String
+  val state: String
+  val type: String
+  val version: String
+  var onmidimessage: (dynamic) -> Unit
+  var onstatechange: (dynamic) -> Unit
+
+  fun open()
+  fun close()
+}
+
+external class MIDIOutput {
+  val connection: String
+  val id: String
+  val manufacturer: String
+  val name: String
+  val state: String
+  val type: String
+  val version: String
+
+  fun send(message: dynamic)
+}
+
+object Midi {
+  var inputs = mutableListOf<MIDIInput>()
+  var outputs = mutableListOf<MIDIInput>()
+  var currentInput: MIDIInput? = null
+
+  fun start() {
+    val navigator = window.navigator.asDynamic()
+
+    navigator.requestMIDIAccess().then(
+      { midiAccess ->
+        val inp = midiAccess.inputs
+        val outp = midiAccess.outputs
+
+        console.log("Midi inputs:", inputs)
+        console.log("Midi outputs:", outputs)
+
+        inp.forEach() { input ->
+          console.log("Midi input:", input)
+          inputs.add(input)
+          console.log("Name: ${(input as? MIDIInput)?.name}")
+        }
+
+        outp.forEach() { output ->
+          console.log("Midi output:", output)
+          outputs.add(output)
+        }
+
+        MainView.requestUpdate()
+      },
+      { e ->
+        println("Failed to get MIDI access - $e")
+      }
+    )
+  }
+
+  fun setInput(input: MIDIInput) {
+    console.log("Setting input", input)
+    currentInput?.close()
+
+    currentInput = input
+
+    currentInput?.onstatechange = { message ->
+      console.log("State change:", message)
+    }
+
+    currentInput?.onmidimessage = { message ->
+      console.log("Midi message:", message)
+      VstChipWorklet.postMessage(
+        message.data
+      )
+    }
+
+    currentInput?.open()
+  }
+
+}