From 966e80fe7328f648925defe349308054e4e86028 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Julien=20D=C3=A9oux?= <juliendeoux@gmail.com>
Date: Fri, 18 Apr 2025 23:06:29 +0200
Subject: [PATCH] Introduction of the AudioDestinationNode module

AudioDestinationNode is a subclass of AudioNode with no constructor and
no extra method. The only effective difference is the `maxChannelCount`
instance property, which is already covered by the
`audioDestinationNode` type in the `WebAudioAPI` module.

This PR allows for `AudioContext`'s `destination` property to be used
like an `AudioNode`, especially being connected to by other nodes since
this is the only way to output audio to speakers.

For more information, check
[MDN](https://developer.mozilla.org/en-US/docs/Web/API/AudioDestinationNode)
---
 src/WebAudioAPI/AudioDestinationNode.js       |  7 ++++
 src/WebAudioAPI/AudioDestinationNode.res      |  5 +++
 .../AudioDestinationNode__.test.js            | 32 +++++++++++++++++++
 .../AudioDestinationNode__.test.res           | 27 ++++++++++++++++
 4 files changed, 71 insertions(+)
 create mode 100644 src/WebAudioAPI/AudioDestinationNode.js
 create mode 100644 src/WebAudioAPI/AudioDestinationNode.res
 create mode 100644 tests/WebAudioAPI/AudioDestinationNode__.test.js
 create mode 100644 tests/WebAudioAPI/AudioDestinationNode__.test.res

diff --git a/src/WebAudioAPI/AudioDestinationNode.js b/src/WebAudioAPI/AudioDestinationNode.js
new file mode 100644
index 0000000..22c59b6
--- /dev/null
+++ b/src/WebAudioAPI/AudioDestinationNode.js
@@ -0,0 +1,7 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+
+import * as AudioNode$WebAPI from "./AudioNode.js";
+
+AudioNode$WebAPI.Impl({});
+
+/*  Not a pure module */
diff --git a/src/WebAudioAPI/AudioDestinationNode.res b/src/WebAudioAPI/AudioDestinationNode.res
new file mode 100644
index 0000000..eb3df0c
--- /dev/null
+++ b/src/WebAudioAPI/AudioDestinationNode.res
@@ -0,0 +1,5 @@
+open WebAudioAPI
+
+include AudioNode.Impl({
+  type t = audioDestinationNode
+})
diff --git a/tests/WebAudioAPI/AudioDestinationNode__.test.js b/tests/WebAudioAPI/AudioDestinationNode__.test.js
new file mode 100644
index 0000000..bd3e6c9
--- /dev/null
+++ b/tests/WebAudioAPI/AudioDestinationNode__.test.js
@@ -0,0 +1,32 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+
+
+let ctx = new AudioContext();
+
+let destinationNode = ctx.destination;
+
+let osc = new OscillatorNode(ctx, {
+  type: "sine",
+  frequency: 440.0
+});
+
+let gain = new GainNode(ctx, {
+  gain: 0.3
+});
+
+gain.connect(destinationNode);
+
+osc.connect(gain);
+
+osc.start();
+
+let context = ctx;
+
+export {
+  ctx,
+  destinationNode,
+  context,
+  osc,
+  gain,
+}
+/* ctx Not a pure module */
diff --git a/tests/WebAudioAPI/AudioDestinationNode__.test.res b/tests/WebAudioAPI/AudioDestinationNode__.test.res
new file mode 100644
index 0000000..7b8acb6
--- /dev/null
+++ b/tests/WebAudioAPI/AudioDestinationNode__.test.res
@@ -0,0 +1,27 @@
+open WebAudioAPI
+
+let ctx = AudioContext.make()
+
+let destinationNode = ctx.destination->AudioDestinationNode.asAudioNode
+let context = AudioContext.asBaseAudioContext(ctx)
+
+let osc = OscillatorNode.make(
+  ~context,
+  ~options={
+    type_: Sine,
+    frequency: 440.0,
+  },
+)
+let gain = GainNode.make(
+  ~context,
+  ~options={
+    gain: 0.3,
+  },
+)
+let _ = gain->GainNode.connect(~destinationNode)
+let _ =
+  osc
+  ->OscillatorNode.asAudioScheduledSourceNode
+  ->AudioScheduledSourceNode.connect(~destinationNode=gain->GainNode.asAudioNode)
+
+osc->OscillatorNode.start