ClosePeerConnection.swift

@IBAction func endCall(_ sender: Any) {
    self.signalClient.deleteSdpAndCandidate(for: self.currentPerson)
    self.webRTCClient.closePeerConnection()
    
    self.webRTCClient.createPeerConnection()
    self.hasLocalSdp = false
    self.localCandidateCount = 0
    self.hasRemoteSdp = false
    self.remoteCandidateCount = 0
  }
  
  func deleteSdpAndCandidate(for person: String) {
    Firestore.firestore().collection(person).document("sdp").delete() { err in
      if let err = err {
        print("Error removing firestore sdp: \(err)")
      } else {
        print("Firestore sdp successfully removed!")
      }
    }
    
    Firestore.firestore().collection(person).document("candidate").delete() { err in
      if let err = err {
        print("Error removing firestore candidate: \(err)")
      } else {
        print("Firestore candidate successfully removed!")
      }
    }
  }

func closePeerConnection() {
    self.peerConnection!.close()
    self.peerConnection = nil
  }