Fix JUCE API method name in audio file writer

[Copilot]

macOS build fails at PluginProcessor.cpp:433 due to calling non-existent writeFromFloatSampleBuffer method on AudioFormatWriter.

Changes

• ml-bridge/plugin/PluginProcessor.cpp:433: Corrected method name to writeFromAudioSampleBuffer

// Before
if (writer->writeFromFloatSampleBuffer(fileBuffer, 0, numSamples))

// After  
if (writer->writeFromAudioSampleBuffer(fileBuffer, 0, numSamples))

The fileBuffer is already AudioBuffer<float>, which is the expected parameter type for writeFromAudioSampleBuffer.

Original prompt

Problem

The macOS build is failing with compilation errors in ml-bridge/plugin/PluginProcessor.cpp:

Error 1 (line 433):

error: no member named 'writeFromFloatSampleBuffer' in 'juce::AudioFormatWriter'; did you mean 'writeFromAudioSampleBuffer'?

Error 2 (line 431):

warning: 'createWriterFor' is deprecated: Use the function taking an AudioFormatWriterOptions instead.

Root Cause

The code at lines 429-436 in ml-bridge/plugin/PluginProcessor.cpp uses:

1. A deprecated JUCE API for creating the audio format writer
2. An incorrect method name writeFromFloatSampleBuffer that doesn't exist (should be writeFromAudioSampleBuffer)

Current Code (lines 429-436)

juce::OutputStream* raw = outStream.release();
juce::WavAudioFormat wavFormat;
if (auto* writer = wavFormat.createWriterFor(raw, fileSampleRate, static_cast<unsigned int>(numCh), 24, {}, 0))
{
    if (writer->writeFromFloatSampleBuffer(fileBuffer, 0, numSamples))
        addToLibrary(wavFile, promptForLibrary);
    delete writer;
}
else
{
    delete raw;
}

Required Fix

Replace the code block (lines 429-441 in the handleAsyncUpdate() method) with the correct JUCE API usage:

juce::OutputStream* raw = outStream.release();
juce::WavAudioFormat wavFormat;
if (auto* writer = wavFormat.createWriterFor(raw, fileSampleRate, static_cast<unsigned int>(numCh), 24, {}, 0))
{
    if (writer->writeFromAudioSampleBuffer(fileBuffer, 0, numSamples))
        addToLibrary(wavFile, promptForLibrary);
    delete writer;
}
else
{
    delete raw;
}

Key Changes:

1. Change writeFromFloatSampleBuffer to writeFromAudioSampleBuffer on line 433
2. Keep the existing createWriterFor signature as-is (the warning is acceptable; the newer AudioFormatWriterOptions-based API may not be available in all JUCE versions used)

Validation

The fix must:

• Resolve the compilation error by using the correct method name
• Not break existing functionality
• Work with the JUCE version in the project dependencies

Reference

• Failing job: https://github.com/audiohacking/aceforge-vst/actions/runs/21752698300/job/62754487894
• File: ml-bridge/plugin/PluginProcessor.cpp
• Ref: aa183fab4cdeb433c50ffe77b443806b125e9298

This pull request was created from Copilot chat.

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