From e072b35854448c14d7d3b938e05c699385081c68 Mon Sep 17 00:00:00 2001
From: Jeff Schiller <codedread@gmail.com>
Date: Sat, 30 Sep 2023 11:17:16 -0700
Subject: [PATCH] Fix for m4a files as audio/mp4. Up-rev to 1.1.2.

---
 CHANGELOG.md         |  4 ++++
 codecs/codecs.js     |  5 +++++
 package-lock.json    |  4 ++--
 package.json         |  2 +-
 tests/codecs.spec.js | 41 ++++++++++++++++++++++++++++-------------
 5 files changed, 40 insertions(+), 16 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 38098ad..2f6eef3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 All notable changes to this project will be documented in this file.
 
+## [1.1.2] - 2023-09-30
+
+- codecs: Handle m4a files as audio/mp4.
+
 ## [1.1.1] - 2023-06-21
 
 - Fix missing RarVM import in unrar.js.
diff --git a/codecs/codecs.js b/codecs/codecs.js
index 7329860..fef8d5f 100644
--- a/codecs/codecs.js
+++ b/codecs/codecs.js
@@ -58,6 +58,11 @@ export function getShortMIMEString(info) {
     return 'audio/flac';
   }
 
+  // M4A files are specifically audio/mp4.
+  if (info?.format?.filename?.toLowerCase().endsWith('.m4a')) {
+    return 'audio/mp4';
+  }
+
   // Otherwise, any file with at least 1 video stream is considered video/.
   // Otherwise, any file with at least 1 audio stream is considered audio/.
   const type = info.streams.some(s => s.codec_type === 'video') ?
diff --git a/package-lock.json b/package-lock.json
index 4b457c8..cb8a985 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@codedread/bitjs",
-  "version": "1.0.11",
+  "version": "1.1.2",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "@codedread/bitjs",
-      "version": "1.0.11",
+      "version": "1.1.2",
       "license": "MIT",
       "devDependencies": {
         "c8": "^7.12.0",
diff --git a/package.json b/package.json
index db5e085..62889db 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@codedread/bitjs",
-  "version": "1.1.1",
+  "version": "1.1.2",
   "description": "Binary Tools for JavaScript",
   "homepage": "https://github.com/codedread/bitjs",
   "author": "Jeff Schiller",
diff --git a/tests/codecs.spec.js b/tests/codecs.spec.js
index c84fa58..b5f493f 100644
--- a/tests/codecs.spec.js
+++ b/tests/codecs.spec.js
@@ -75,6 +75,13 @@ describe('codecs test suite', () => {
       })).equals('audio/mpeg');
     });
 
+    it('detects M4A audio', () => {
+      expect(getShortMIMEString({
+        format: { filename: 'sample.m4a', format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
+        streams: [ { codec_type: 'video', }, { codec_type: 'audio' } ],
+      })).equals('audio/mp4');
+    });
+
     it('detects MP4 video', () => {
       expect(getShortMIMEString({
         format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
@@ -306,24 +313,21 @@ describe('codecs test suite', () => {
 
   describe('MP4A / AAC', () => {
     /** @type {ProbeInfo} */
-    let info;
-
-    beforeEach(() => {
-      info = {
-        format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
-        streams: [{
-          codec_type: 'audio',
-          codec_tag_string: 'mp4a',
-        }],
-      };
-    });
+    let baseInfo = {
+      format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
+      streams: [{
+        codec_type: 'audio',
+        codec_tag_string: 'mp4a',
+      }],
+    };
 
     it('throws when unknown', () => {
-      expect(() => getFullMIMEString(info)).to.throw();
+      expect(() => getFullMIMEString(baseInfo)).to.throw();
     });
 
     describe('Profile tests', () => {
       it('recognizes AAC-LC', () => {
+        const info = structuredClone(baseInfo);
         info.streams[0].profile = 'LC';
         expect(getFullMIMEString(info))
             .to.be.a('string')
@@ -332,6 +336,7 @@ describe('codecs test suite', () => {
     });
 
     it('handles codec_name=aac but no codec_tag_string', () => {
+      const info = structuredClone(baseInfo);
       info.streams[0].profile = 'LC';
       info.streams[0].codec_tag_string = '[0][0][0][0]';
       info.streams[0].codec_name = 'aac';
@@ -339,6 +344,16 @@ describe('codecs test suite', () => {
           .to.be.a('string')
           .and.equals('audio/mp4; codecs="mp4a.40.2"');
     });
+
+    it('handles m4a file with MJPEG stream', () => {
+      const info = structuredClone(baseInfo);
+      info.format.filename = 'sample.m4a';
+      info.streams[0].profile = 'LC';
+      info.streams.push({codec_name: 'mjpeg', codec_type: 'video', profile: 'Baseline'});
+      expect(getFullMIMEString(info))
+          .to.be.a('string')
+          .and.equals('audio/mp4; codecs="mp4a.40.2"');
+    })
   });
 
   describe('MP4 / FLAC', () => {
@@ -374,7 +389,7 @@ describe('codecs test suite', () => {
       expect(getFullMIMEString(vInfo))
           .to.be.a('string')
           .and.equals('video/mp4; codecs="flac"');
-      
+
     });
   });