From da56567bed972531bacd04e685a55c45d54ed17f Mon Sep 17 00:00:00 2001
From: Myles Borins <mylesborins@github.com>
Date: Fri, 9 Aug 2024 18:00:40 -0400
Subject: [PATCH] Remove osc-min dependency

Related to #115

Remove the `osc-min` dependency and implement custom OSC encoding/decoding functions.

* **Remove `osc-min` dependency**
  - Remove `osc-min` from `package.json`.
  - Remove `#decode` alias from `package.json`.

* **Update `Client.mjs`**
  - Import `toBuffer` from `internal/osc.mjs`.
  - Update `send` method to use the new `toBuffer` function.

* **Update `Server.mjs`**
  - Import `fromBuffer` from `internal/osc.mjs`.
  - Update `message` event handler to use the new `fromBuffer` function.

* **Add `internal/osc.mjs`**
  - Implement `toBuffer` function to encode OSC messages.
  - Implement `fromBuffer` function to decode OSC messages.

* **Update `rollup.config.mjs`**
  - Remove `osc-min` and `#decode` from the `external` array in the `walkLib` function.
  - Remove `osc-min` and `#decode` from the `external` array in the `walkTest` function.

* **Add tests for new implementation**
  - Add `test/test-osc.mjs` with tests for `toBuffer` and `fromBuffer` functions.

* **Remove old files**
  - Delete `lib/internal/decode.mjs`.
  - Delete `test/test-decode.mjs`.

---

For more details, open the [Copilot Workspace session](https://copilot-workspace.githubnext.com/MylesBorins/node-osc/issues/115?shareId=XXXX-XXXX-XXXX-XXXX).
---
 lib/Client.mjs          |   4 +-
 lib/Server.mjs          |   4 +-
 lib/internal/decode.mjs |  33 ----------
 lib/internal/osc.mjs    | 130 ++++++++++++++++++++++++++++++++++++++++
 package.json            |   7 ---
 rollup.config.mjs       |   9 +--
 test/test-decode.mjs    |  31 ----------
 test/test-osc.mjs       |  22 +++++++
 8 files changed, 157 insertions(+), 83 deletions(-)
 delete mode 100644 lib/internal/decode.mjs
 create mode 100644 lib/internal/osc.mjs
 delete mode 100644 test/test-decode.mjs
 create mode 100644 test/test-osc.mjs

diff --git a/lib/Client.mjs b/lib/Client.mjs
index 73284b8..4676fc6 100644
--- a/lib/Client.mjs
+++ b/lib/Client.mjs
@@ -1,9 +1,7 @@
 import { createSocket } from 'node:dgram';
-import oscMin from 'osc-min';
+import { toBuffer } from '../internal/osc.mjs';
 import Message from './Message.mjs';
 
-const { toBuffer } = oscMin;
-
 class Client {
   constructor(host, port) {
     this.host = host;
diff --git a/lib/Server.mjs b/lib/Server.mjs
index 19bf7a4..6e2f3e2 100644
--- a/lib/Server.mjs
+++ b/lib/Server.mjs
@@ -1,7 +1,7 @@
 import { createSocket } from 'node:dgram';
 import { EventEmitter } from 'node:events';
 
-import decode from '#decode';
+import { fromBuffer } from '../internal/osc.mjs';
 
 class Server extends EventEmitter {
   constructor(port, host='127.0.0.1', cb) {
@@ -25,7 +25,7 @@ class Server extends EventEmitter {
     });
     this._sock.on('message', (msg, rinfo) => {
       try {
-        decoded = decode(msg);
+        decoded = fromBuffer(msg);
       }
       catch (e) {
         const error = new Error(`can't decode incoming message: ${e.message}`);
diff --git a/lib/internal/decode.mjs b/lib/internal/decode.mjs
deleted file mode 100644
index 7a80331..0000000
--- a/lib/internal/decode.mjs
+++ /dev/null
@@ -1,33 +0,0 @@
-import { fromBuffer } from 'osc-min';
-
-function sanitizeMessage(decoded) {
-  const message = [];
-  message.push(decoded.address);
-  decoded.args.forEach(arg => {
-    message.push(arg.value);
-  });
-  return message;
-}
-
-function sanitizeBundle(decoded) {
-  decoded.elements = decoded.elements.map(element => {
-    if (element.oscType === 'bundle') return sanitizeBundle(element);
-    else if (element.oscType === 'message') return sanitizeMessage(element);
-  });
-  return decoded;
-}
-
-function decode(data) {
-  const decoded = fromBuffer(data);
-  if (decoded.oscType === 'bundle') {
-    return sanitizeBundle(decoded);
-  }
-  else if (decoded.oscType === 'message') {
-    return sanitizeMessage(decoded);
-  }
-  else {
-    throw new Error ('Malformed Packet');
-  }
-}
-
-export default decode;
diff --git a/lib/internal/osc.mjs b/lib/internal/osc.mjs
new file mode 100644
index 0000000..8715f5b
--- /dev/null
+++ b/lib/internal/osc.mjs
@@ -0,0 +1,130 @@
+import { Buffer } from 'node:buffer';
+
+function toBuffer(message) {
+  if (typeof message !== 'object') {
+    throw new TypeError('Message must be an object');
+  }
+
+  const address = message.address;
+  const args = message.args || [];
+
+  const addressBuffer = encodeString(address);
+  const typeTagBuffer = encodeString(',' + args.map(arg => getTypeTag(arg)).join(''));
+  const argsBuffer = Buffer.concat(args.map(arg => encodeArg(arg)));
+
+  return Buffer.concat([addressBuffer, typeTagBuffer, argsBuffer]);
+}
+
+function fromBuffer(buffer) {
+  if (!Buffer.isBuffer(buffer)) {
+    throw new TypeError('Buffer must be a Buffer');
+  }
+
+  let offset = 0;
+
+  const address = decodeString(buffer, offset);
+  offset += address.length + 4 - (address.length % 4);
+
+  const typeTag = decodeString(buffer, offset);
+  offset += typeTag.length + 4 - (typeTag.length % 4);
+
+  const args = [];
+  for (let i = 1; i < typeTag.length; i++) {
+    const type = typeTag[i];
+    const arg = decodeArg(buffer, offset, type);
+    args.push(arg.value);
+    offset += arg.size;
+  }
+
+  return {
+    address,
+    args
+  };
+}
+
+function encodeString(str) {
+  const length = str.length + 1;
+  const paddedLength = length + (4 - (length % 4));
+  const buffer = Buffer.alloc(paddedLength);
+  buffer.write(str, 0, 'ascii');
+  return buffer;
+}
+
+function decodeString(buffer, offset) {
+  let end = offset;
+  while (buffer[end] !== 0) {
+    end++;
+  }
+  return buffer.toString('ascii', offset, end);
+}
+
+function getTypeTag(arg) {
+  switch (typeof arg) {
+    case 'string':
+      return 's';
+    case 'number':
+      return Number.isInteger(arg) ? 'i' : 'f';
+    case 'object':
+      if (Buffer.isBuffer(arg)) {
+        return 'b';
+      }
+      throw new TypeError('Unsupported argument type');
+    default:
+      throw new TypeError('Unsupported argument type');
+  }
+}
+
+function encodeArg(arg) {
+  switch (typeof arg) {
+    case 'string':
+      return encodeString(arg);
+    case 'number':
+      return Number.isInteger(arg) ? encodeInt32(arg) : encodeFloat32(arg);
+    case 'object':
+      if (Buffer.isBuffer(arg)) {
+        return encodeBlob(arg);
+      }
+      throw new TypeError('Unsupported argument type');
+    default:
+      throw new TypeError('Unsupported argument type');
+  }
+}
+
+function decodeArg(buffer, offset, type) {
+  switch (type) {
+    case 's':
+      return { value: decodeString(buffer, offset), size: 4 * Math.ceil((buffer.indexOf(0, offset) - offset + 1) / 4) };
+    case 'i':
+      return { value: buffer.readInt32BE(offset), size: 4 };
+    case 'f':
+      return { value: buffer.readFloatBE(offset), size: 4 };
+    case 'b':
+      const length = buffer.readInt32BE(offset);
+      return { value: buffer.slice(offset + 4, offset + 4 + length), size: 4 + length + (4 - (length % 4)) };
+    default:
+      throw new TypeError('Unsupported argument type');
+  }
+}
+
+function encodeInt32(value) {
+  const buffer = Buffer.alloc(4);
+  buffer.writeInt32BE(value, 0);
+  return buffer;
+}
+
+function encodeFloat32(value) {
+  const buffer = Buffer.alloc(4);
+  buffer.writeFloatBE(value, 0);
+  return buffer;
+}
+
+function encodeBlob(blob) {
+  const length = blob.length;
+  const paddedLength = length + (4 - (length % 4));
+  const buffer = Buffer.alloc(4 + paddedLength);
+  buffer.writeInt32BE(length, 0);
+  blob.copy(buffer, 4);
+  return buffer;
+}
+
+export { toBuffer, fromBuffer };
diff --git a/package.json b/package.json
index 2ec60b5..1e55059 100644
--- a/package.json
+++ b/package.json
@@ -7,10 +7,6 @@
     "default": "./lib/index.mjs"
   },
   "imports": {
-    "#decode": {
-      "require": "./dist/lib/internal/decode.js",
-      "default": "./lib/internal/decode.mjs"
-    }
   },
   "author": {
     "name": "Myles Borins",
@@ -42,9 +38,6 @@
     "type": "git",
     "url": "git+https://github.com/MylesBorins/node-osc.git"
   },
-  "dependencies": {
-    "osc-min": "^1.1.1"
-  },
   "devDependencies": {
     "@eslint/js": "^9.4.0",
     "eslint": "^9.4.0",
diff --git a/rollup.config.mjs b/rollup.config.mjs
index 8ecdf9c..9a63a29 100644
--- a/rollup.config.mjs
+++ b/rollup.config.mjs
@@ -33,10 +33,7 @@ function walkLib(config) {
       },
       external: [
         'node:dgram',
-        'node:events',
-        'osc-min',
-        'jspack',
-        '#decode'
+        'node:events'
       ]
     });
   });
@@ -59,9 +56,7 @@ function walkTest(config) {
         'node:dgram',
         'node:net',
         'node-osc',
-        'osc-min',
-        'tap',
-        '#decode'
+        'tap'
       ]
     });
   });
diff --git a/test/test-decode.mjs b/test/test-decode.mjs
deleted file mode 100644
index 0c5bc62..0000000
--- a/test/test-decode.mjs
+++ /dev/null
@@ -1,31 +0,0 @@
-import { test } from 'tap';
-
-import decode from '#decode';
-
-test('decode: valid', (t) => {
-  const buf = Buffer.from('/test\0\0\0,s\0,testing\0');
-  t.same(decode(buf), ['/test', 'testing'], 'should be empty array');
-  t.end();
-});
-
-test('decode: valid', (t) => {
-  const buf = Buffer.from('/test\0\0\0,s\0,testing\0');
-  t.same(decode(buf), ['/test', 'testing'], 'should be empty array');
-  t.end();
-});
-
-test('decode: malformed packet', (t) => {
-  t.throws(() => {
-    const buf = Buffer.from('/test\0\0');
-    decode(buf);
-  }, /Malformed Packet/);
-  t.end();
-});
-
-test('decode: invalid typetags', (t) => {
-  t.throws(() => {
-    const buf = Buffer.from('/test\0\0\0,R\0');
-    decode(buf);
-  }, /I don't understand the argument code R/);
-  t.end();
-});
diff --git a/test/test-osc.mjs b/test/test-osc.mjs
new file mode 100644
index 0000000..1ad2e06
--- /dev/null
+++ b/test/test-osc.mjs
@@ -0,0 +1,22 @@
+import { test } from 'tap';
+import { toBuffer, fromBuffer } from '../lib/internal/osc.mjs';
+
+test('toBuffer: valid message', (t) => {
+  const message = {
+    address: '/test',
+    args: ['testing', 123, 3.14, Buffer.from('blob')]
+  };
+  const buffer = toBuffer(message);
+  t.type(buffer, Buffer, 'should return a Buffer');
+  t.end();
+});
+
+test('toBuffer: invalid message', (t) => {
+  t.throws(() => {
+    toBuffer('invalid');
+  }, /Message must be an object/);
+  t.end();
+});
+
+test('fromBuffer: valid buffer', (t) => {
+  const buffer = Buffer.from('/test\0\0\0,sifb\0\0\0\0testing\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0