From b6443fcf1798c39e3d78964a99e85b811516e670 Mon Sep 17 00:00:00 2001
From: Squarebananas <squarebananas@hotmail.com>
Date: Mon, 26 Aug 2024 22:06:03 +0100
Subject: [PATCH] Removes incorrect ADPCM encoder's block size requirement (to
 fix MonoGame issue #6701)

---
 build/BuildCommon.cs      | 20 ++++++++++++++++++++
 build/BuildLinuxTask.cs   |  3 ++-
 build/BuildMacOSTask.cs   |  3 ++-
 build/BuildWIndowsTask.cs |  3 ++-
 4 files changed, 26 insertions(+), 3 deletions(-)
 create mode 100644 build/BuildCommon.cs

diff --git a/build/BuildCommon.cs b/build/BuildCommon.cs
new file mode 100644
index 0000000..6dc0aba
--- /dev/null
+++ b/build/BuildCommon.cs
@@ -0,0 +1,20 @@
+namespace BuildScripts;
+
+static class BuildCommon
+{
+    // There is an issue with FFmpeg that causes incompatible reduced quality audio (MGCB medium & low settings)
+    // to be produced for XAudio2 playback. For reference a ticket has been opened at https://trac.ffmpeg.org/ticket/9397#ticket
+    // (samples per block should be a power of 2, however FFmpeg incorrectly forces this requirement on the block size
+    // instead). For now, we'll just patch out the encoder's power of 2 check.
+    public static void FFmpegApplyXAudio2Fix(BuildContext context)
+    {
+        string filePath = "./ffmpeg/libavcodec/adpcmenc.c";
+        List<string> lines = context.FileReadLines(filePath).ToList();
+        int lineNumber = lines.FindIndex(x => x.Contains("av_log(avctx, AV_LOG_ERROR, \"block size must be power of 2\\n\");"));
+        if (lineNumber != -1)
+        {
+            lines.RemoveRange(lineNumber, 2);
+            context.FileWriteLines(filePath, lines.ToArray());
+        }
+    }
+}
diff --git a/build/BuildLinuxTask.cs b/build/BuildLinuxTask.cs
index 1d1808f..414f652 100644
--- a/build/BuildLinuxTask.cs
+++ b/build/BuildLinuxTask.cs
@@ -67,10 +67,11 @@ public override void Run(BuildContext context)
         processSettings.Arguments = $"-c \"make install\"";
         context.StartProcess(shellCommandPath, processSettings);
 
-        // Build ffmpeg
+        // Build ffmpeg (with XAudio2 fix)
         processSettings.WorkingDirectory = "./ffmpeg";
         processSettings.Arguments = $"-c \"make distclean\"";
         context.StartProcess(shellCommandPath, processSettings);
+        BuildCommon.FFmpegApplyXAudio2Fix(context);
         processSettings.Arguments = $"-c \"./configure {binDirFlag} {configureFlags}\"";
         context.StartProcess(shellCommandPath, processSettings);
         processSettings.Arguments = $"-c \"make -j{Environment.ProcessorCount}\"";
diff --git a/build/BuildMacOSTask.cs b/build/BuildMacOSTask.cs
index 1f0d782..de3bb3e 100644
--- a/build/BuildMacOSTask.cs
+++ b/build/BuildMacOSTask.cs
@@ -108,10 +108,11 @@ private static void BuildArm64(BuildContext context)
         processSettings.Arguments = $"-c \"make install\"";
         context.StartProcess(shellCommandPath, processSettings);
 
-        // Build ffmpeg
+        // Build ffmpeg (with XAudio2 fix)
         processSettings.WorkingDirectory = "./ffmpeg";
         processSettings.Arguments = $"-c \"make distclean\"";
         context.StartProcess(shellCommandPath, processSettings);
+        BuildCommon.FFmpegApplyXAudio2Fix(context);
         processSettings.Arguments = $"-c \"./configure {binDirFlag} {configureFlags} {progsSuffixFlag}\"";
         context.StartProcess(shellCommandPath, processSettings);
         processSettings.Arguments = $"-c \"make -j{Environment.ProcessorCount}\"";
diff --git a/build/BuildWIndowsTask.cs b/build/BuildWIndowsTask.cs
index 7b8f6d6..4aa53b2 100644
--- a/build/BuildWIndowsTask.cs
+++ b/build/BuildWIndowsTask.cs
@@ -82,10 +82,11 @@ public override void Run(BuildContext context)
         processSettings.Arguments = $"-c \"{exports} make install\"";
         context.StartProcess(shellCommandPath, processSettings);
 
-        // Build ffmpeg
+        // Build ffmpeg (with XAudio2 fix)
         processSettings.WorkingDirectory = "./ffmpeg";
         processSettings.Arguments = $"-c \"{exports} make distclean\"";
         context.StartProcess(shellCommandPath, processSettings);
+        BuildCommon.FFmpegApplyXAudio2Fix(context);
         processSettings.Arguments = $"-c \"{exports} ./configure {binDirFlag} {configureFlags}\"";
         context.StartProcess(shellCommandPath, processSettings);
         processSettings.Arguments = $"-c \"{exports} make -j{Environment.ProcessorCount}\"";