chore: archive mac mini automation baseline

2026-08-03 11:47:09 -04:00
parent a0a26565f0
commit 6e2117188e
93 changed files with 10005 additions and 5 deletions
@@ -0,0 +1,127 @@
+import AVFoundation
+import Foundation
+
+enum AudioCaptureState: Equatable {
+    case idle
+    case starting
+    case recording
+    case failed(String)
+}
+
+@MainActor
+final class AudioCaptureManager: ObservableObject {
+    @Published private(set) var state: AudioCaptureState = .idle
+
+    var onPCMChunk: ((Data) -> Void)?
+
+    private let engine = AVAudioEngine()
+    private var converter: AVAudioConverter?
+    private var inputFormat: AVAudioFormat?
+
+    private let targetFormat = AVAudioFormat(
+        commonFormat: .pcmFormatInt16,
+        sampleRate: 16_000,
+        channels: 1,
+        interleaved: true
+    )!
+
+    func requestPermission() async -> Bool {
+        await withCheckedContinuation { continuation in
+            AVAudioSession.sharedInstance().requestRecordPermission { granted in
+                continuation.resume(returning: granted)
+            }
+        }
+    }
+
+    func startRecording() async {
+        guard state != .recording && state != .starting else { return }
+
+        state = .starting
+
+        guard await requestPermission() else {
+            state = .failed("Microphone permission was denied.")
+            return
+        }
+
+        do {
+            try configureSession()
+            try configureEngine()
+            try engine.start()
+            state = .recording
+        } catch {
+            stopRecording()
+            state = .failed(error.localizedDescription)
+        }
+    }
+
+    func stopRecording() {
+        guard state == .recording || state == .starting else { return }
+
+        engine.inputNode.removeTap(onBus: 0)
+        engine.stop()
+        converter = nil
+        inputFormat = nil
+        state = .idle
+    }
+
+    private func configureSession() throws {
+        let session = AVAudioSession.sharedInstance()
+        try session.setCategory(.playAndRecord, mode: .voiceChat, options: [.defaultToSpeaker])
+        try session.setPreferredSampleRate(16_000)
+        try session.setPreferredIOBufferDuration(0.02)
+        try session.setActive(true)
+    }
+
+    private func configureEngine() throws {
+        let inputNode = engine.inputNode
+        let hardwareFormat = inputNode.outputFormat(forBus: 0)
+        inputFormat = hardwareFormat
+        converter = AVAudioConverter(from: hardwareFormat, to: targetFormat)
+
+        inputNode.removeTap(onBus: 0)
+        inputNode.installTap(onBus: 0, bufferSize: 1024, format: hardwareFormat) { [weak self] buffer, _ in
+            Task { @MainActor in
+                guard let self else { return }
+                guard let data = self.convertToTargetPCM(buffer) else { return }
+                self.onPCMChunk?(data)
+            }
+        }
+
+        engine.prepare()
+    }
+
+    private func convertToTargetPCM(_ inputBuffer: AVAudioPCMBuffer) -> Data? {
+        guard let converter else { return nil }
+
+        let ratio = targetFormat.sampleRate / inputBuffer.format.sampleRate
+        let targetFrameCapacity = AVAudioFrameCount(Double(inputBuffer.frameLength) * ratio) + 1
+        guard let outputBuffer = AVAudioPCMBuffer(pcmFormat: targetFormat, frameCapacity: targetFrameCapacity) else {
+            return nil
+        }
+
+        var didProvideInput = false
+        var conversionError: NSError?
+
+        converter.convert(to: outputBuffer, error: &conversionError) { _, status in
+            if didProvideInput {
+                status.pointee = .noDataNow
+                return nil
+            }
+
+            didProvideInput = true
+            status.pointee = .haveData
+            return inputBuffer
+        }
+
+        guard conversionError == nil else { return nil }
+        return outputBuffer.interleavedPCMData()
+    }
+}
+
+private extension AVAudioPCMBuffer {
+    func interleavedPCMData() -> Data? {
+        let audioBuffer = audioBufferList.pointee.mBuffers
+        guard let source = audioBuffer.mData else { return nil }
+        return Data(bytes: source, count: Int(audioBuffer.mDataByteSize))
+    }
+}