// My custom HTML5 video player
const player = new Player(document.querySelector('#my-video'))

const context = cast.framework.CastReceiverContext.getInstance()
const playerManager = context.getPlayerManager()
playerManager.setMediaElement(document.querySelector('#my-video'))
// Now, I need to override some of the playerManager methods such as play/pause, etc
const overrides = {
  getCurrentTimeSec () {
    return player.currentTime
  },
  getPlayerState () {
    const PlayerState = cast.framework.messages.PlayerState
    if (!player.ready || !player.source) {
      return PlayerState.IDLE
    }
    return player.paused ? PlayerState.PAUSED : PlayerState.PLAYING
  },
  getDurationSec () {
    return player.duration
  },
  pause: player.pause,
  play: player.play,
  seek: player.seek,
  load: (loadRequestData) => {
  return new Promise((resolve, reject) => {
    // Parse loadRequestData and load the media accordingly
    ...
  })
}
Object.assign(playerManager, overrides)

context.start();

playerManager.setMessageInterceptor(
    cast.framework.messages.MessageType.LOAD,
    request => {
      ...
})