//
//  CameraView+AVAudioSession.swift
//  VisionCamera
//
//  Created by Marc Rousavy on 26.03.21.
//  Copyright © 2021 Facebook. All rights reserved.
//

import Foundation
import AVFoundation

/**
 Extension for CameraView that sets up the AVAudioSession.
 */
extension CameraView {
  @objc
  func audioSessionInterrupted(notification: Notification) {
    ReactLogger.log(level: .error, message: "The Audio Session was interrupted!")
    guard let userInfo = notification.userInfo,
          let typeValue = userInfo[AVAudioSessionInterruptionTypeKey] as? UInt,
          let type = AVAudioSession.InterruptionType(rawValue: typeValue) else {
      return
    }
    switch type {
    case .began:
      // TODO: Should we also disable the camera here? I think it will throw a runtime error
      // disable audio session
      try? AVAudioSession.sharedInstance().setActive(false)
      break
    case .ended:
      guard let optionsValue = userInfo[AVAudioSessionInterruptionOptionKey] as? UInt else { return }
      let options = AVAudioSession.InterruptionOptions(rawValue: optionsValue)
      if options.contains(.shouldResume) {
        // restart audio session because interruption is over
        configureAudioSession()
      } else {
        ReactLogger.log(level: .error, message: "Cannot resume interrupted Audio Session!")
      }
      break
    }
  }
  
  private final func setAutomaticallyConfiguresAudioSession(_ automaticallyConfiguresAudioSession: Bool) {
    if captureSession.automaticallyConfiguresApplicationAudioSession != automaticallyConfiguresAudioSession {
      captureSession.beginConfiguration()
      captureSession.automaticallyConfiguresApplicationAudioSession = automaticallyConfiguresAudioSession
      captureSession.commitConfiguration()
    }
  }
  
  /**
   Configures the Audio session to allow background-music playback while recording.
   */
  internal final func configureAudioSession() {
    let start = DispatchTime.now()
    do {
      setAutomaticallyConfiguresAudioSession(false)
      let audioSession = AVAudioSession.sharedInstance()
      if audioSession.category != .playAndRecord {
        // allow background music playback
        try audioSession.setCategory(AVAudioSession.Category.playAndRecord, options: [.mixWithOthers, .allowBluetoothA2DP, .defaultToSpeaker])
      }
      // TODO: Use https://developer.apple.com/documentation/avfaudio/avaudiosession/3726094-setprefersnointerruptionsfromsys
      audioSession.trySetAllowHaptics(true)
      // activate current audio session because camera is active
      try audioSession.setActive(true)
    } catch let error as NSError {
      self.invokeOnError(.session(.audioSessionSetupFailed(reason: error.description)), cause: error)
      setAutomaticallyConfiguresAudioSession(true)
    }
    let end = DispatchTime.now()
    let nanoTime = end.uptimeNanoseconds - start.uptimeNanoseconds
    ReactLogger.log(level: .info, message: "Configured Audio session in \(Double(nanoTime) / 1_000_000)ms!")
  }
}