Best Implementation of .wav Audio Recording in Swift - ios

Question

Thanks in advance for your help,
I have been able to record in .m4a format for a while. Unfortunately, this project I'm working on needs to be recorded in .wav. I have been searching for a way of recording in .wav but I've only been able to find resources on converting to .wav after recording in .m4a. Is there a way of recording specifically in .wav?
The code I've pasted is my recording service. In settings specifically, I pass an audio format type. I haven't been able to have this type be of '.wav'.
import Foundation
import Combine
import AVFoundation
class AudioRecorder: NSObject, ObservableObject {
override init() {
super.init()
fetchRecordings()
}
let objectWillChange = PassthroughSubject<AudioRecorder, Never>()
var audioRecorder: AVAudioRecorder!
var recordings = [Recording]()
var recording = false {
didSet {
objectWillChange.send(self)
}
}
func startRecording(taskNum: Int) {
let recordingSession = AVAudioSession.sharedInstance()
do {
try recordingSession.setCategory(.playAndRecord, mode: .default)
try recordingSession.setActive(true)
} catch {
print("Failed to set up recording session")
}
let documentPath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
let audioFilename = documentPath.appendingPathComponent("\(Date().toString(dateFormat: "dd-MM-YY_'at'_HH:mm:ss"))-task_\(taskNum).m4a")
let settings = [
// Change to kAudioFileWAVEType from kAudioFormatMPEG4AAC for .wav files?
AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
AVSampleRateKey: 12000,
AVNumberOfChannelsKey: 1,
AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue
]
do {
audioRecorder = try AVAudioRecorder(url: audioFilename, settings: settings)
audioRecorder.record()
recording = true
} catch {
print("Could not start recording")
}
}
func stopRecording() {
audioRecorder.stop()
recording = false
fetchRecordings()
}
func fetchRecordings() {
recordings.removeAll()
let fileManager = FileManager.default
let documentDirectory = fileManager.urls(for: .documentDirectory, in: .userDomainMask)[0]
let directoryContents = try! fileManager.contentsOfDirectory(at: documentDirectory, includingPropertiesForKeys: nil)
for audio in directoryContents {
let recording = Recording(fileURL: audio, createdAt: getCreationDate(for: audio))
recordings.append(recording)
}
recordings.sort(by: { $0.createdAt.compare($1.createdAt) == .orderedAscending})
objectWillChange.send(self)
}
func getCreationDate(for file: URL) -> Date {
if let attributes = try? FileManager.default.attributesOfItem(atPath: file.path) as [FileAttributeKey: Any],
let creationDate = attributes[FileAttributeKey.creationDate] as? Date {
return creationDate
} else {
return Date()
}
}
func deleteRecording(urlsToDelete: [URL]) {
for url in urlsToDelete {
print(url)
do {
try FileManager.default.removeItem(at: url)
} catch {
print("File could not be deleted!")
}
}
fetchRecordings()
}
}