Samplem4a

Samplem4a.swift

//
//  ViewController.swift
//  Samplem4a
//
//  Created by 永田大祐 on 2021/03/28.
//

import UIKit
import AVFoundation

class ViewController: UIViewController {

    private var btPlay = UIButton()
    private var btRecord = UIButton()
    private var player = AudioEnginePlayer()

    override func viewDidLoad() {
        super.viewDidLoad()

        btPlay.frame = CGRect(x: 0,
                          y: view.frame.height - 200,
                          width: self.view.frame.width,
                          height: 100)
        btPlay.addTarget(self, action: #selector(playBack), for: .touchUpInside)
        btPlay.setTitle("Play", for: .normal)
        btPlay.setTitleColor(.black, for: .normal)
        view.addSubview(btPlay)

        btRecord.frame = CGRect(x: 0,
                          y: view.frame.height - 100,
                          width: self.view.frame.width,
                          height: 100)
        btRecord.addTarget(self, action: #selector(record), for: .touchUpInside)
        btRecord.setTitle("Record", for: .normal)
        btRecord.setTitleColor(.black, for: .normal)
        view.addSubview(btRecord)
    }

    @objc func playBack() {
        player.stop()
        player.play()
    }

    @objc func record() {
        player.stop()
        player.record()
    }
}

class AudioEnginePlayer {

    var audioPlayerNode: AVAudioPlayerNode = AVAudioPlayerNode()
    var audioEngine: AVAudioEngine = AVAudioEngine()

    private var audioFile: AVAudioFile?
    private var session = AVAudioSession.sharedInstance()

    init() {
        setFile(url: getAudioFileUrl())
    }

    func play() {
        guard !audioEngine.isRunning, audioFile == nil else { return }
        do {
            let audioFile = try AVAudioFile(forReading: getAudioFileUrl())
            audioPlayerNode.scheduleFile(audioFile, at: nil, completionHandler: nil)
            try audioEngine.start()
            audioPlayerNode.play()
        } catch let error {
            print(error)
        }
    }

    func record() {

        setFile(url: getAudioFileUrl())
        audioEngine.inputNode.installTap(onBus: 0, bufferSize: 1024, format: audioEngine.inputNode.outputFormat(forBus: 0)) { [self] (buffer, time) in
            do {
                try audioFile?.write(from: buffer)
            } catch let error {
                print(error, "error")
            }
        }
        setUrl()
    }

    // audioFile = nilをしないとファイルが動作しない
    func stop() {
        audioPlayerNode.stop()
        audioEngine.stop()
        audioEngine.inputNode.removeTap(onBus: 0)
        audioFile = nil
    }

    func getAudioFileUrl() -> URL {
        let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        return documentsDirectory.appendingPathComponent("sample.m4a")
    }

    private func setUrl() {

        // Prepare AVAudioPlayerNode
        audioEngine.attach(audioPlayerNode)
        audioEngine.connect(audioPlayerNode, to: audioEngine.mainMixerNode, format: audioFile?.processingFormat)
        do {
            audioEngine.prepare()
            try audioEngine.start()
        } catch let error {
            print(error)
        }
    }

    private func setFile(url: URL) {
        do {
            let format = AVAudioFormat(commonFormat: .pcmFormatInt32 , sampleRate: AVAudioSession.sharedInstance().sampleRate, channels: 1 , interleaved: false)
            audioFile = try AVAudioFile(forWriting:url, settings: format!.settings)
            sessionEngine()
        } catch let error {
            print(error)
        }
    }

    private func sessionEngine() {
        do {
            try session.setCategory(.playAndRecord, mode: .default, options: .defaultToSpeaker)
            try session.overrideOutputAudioPort(.speaker)
            try session.setPreferredSampleRate(AVAudioSession.sharedInstance().sampleRate)
            try session.setActive(true)
            
        } catch let error {
            print("engine.start() error:", error)
        }
    }
}