service.js

import TrackPlayer, { Event, State } from 'react-native-track-player'

let wasPausedByDuck = false

module.exports = async function setup() {
  TrackPlayer.addEventListener(Event.RemotePause, () => {
    TrackPlayer.pause()
  })

  TrackPlayer.addEventListener(Event.RemotePlay, () => {
    TrackPlayer.play()
  })

  TrackPlayer.addEventListener(Event.RemoteNext, () => {
    TrackPlayer.skipToNext()
  })

  TrackPlayer.addEventListener(Event.RemotePrevious, () => {
    TrackPlayer.skipToPrevious()
  })

  TrackPlayer.addEventListener(Event.RemoteDuck, async (e) => {
    if (e.permanent === true) {
      TrackPlayer.stop()
    } else {
      if (e.paused === true) {
        const playerState = await TrackPlayer.getState()
        wasPausedByDuck = playerState !== State.Paused
        TrackPlayer.pause()
      } else {
        if (wasPausedByDuck === true) {
          TrackPlayer.play()
          wasPausedByDuck = false
        }
      }
    }
  })
}