Rotation issues - Please help

Hi all, basically I'm making a simple game where I have a world object and the camera fixed to look at it and you can orbit the camera around it. When you zoom in a certain distance I want the camera to smoothly switch to looking at the player character and then rotating the camera will smoothly orbit the player.

I got as far as getting the zooming in and smoothly orbiting the player working but its doesn't smoothly switch it jumps from one target to the other and when I try to make it smooth it works but then messes up the orbit.

any help please.

 using UnityEngine;
 using System.Collections;
 
 public class Camera1 : MonoBehaviour
 {
     public Transform target;
     public Transform player;
     public float distance = 5.0f;
     public float xSpeed = 120.0f;
     public float ySpeed = 120.0f;
     public float rotationspeed = 2.0f;
 
     public int x = 0;
 
     public float yMinLimit = -20f;
     public float yMaxLimit = 80f;
 
     public float distanceMin = .5f;
     public float distanceMax = 15f;
 
     public float smoothTime = 2f;
 
     float rotationYAxis = 0.0f;
     float rotationXAxis = 0.0f;
 
     float velocityX = 0.0f;
     float velocityY = 0.0f;
 
     float minFov = 15f;
     float maxFov = 90f;
     float sensitivity = 10f;
 
     // Use this for initialization
     void Start()
     {
         Vector3 angles = transform.eulerAngles;
         rotationYAxis = angles.y;
         rotationXAxis = angles.x;
         PlayerPrefs.SetInt("FollowPlayer", 0);
     }
 
     void LateUpdate()
     {
         if (target)
         {
 
             rotationYAxis += velocityX;
             rotationXAxis -= velocityY;
 
             rotationXAxis = ClampAngle(rotationXAxis, yMinLimit, yMaxLimit);
 
             Quaternion fromRotation = Quaternion.Euler(transform.rotation.eulerAngles.x, transform.rotation.eulerAngles.y, 0);
             Quaternion toRotation = Quaternion.Euler(rotationXAxis, rotationYAxis, 0);
             Quaternion rotation = toRotation;
 
             Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
 
             if (Input.GetMouseButton(1))
             {
                 velocityX += xSpeed * Input.GetAxis("Mouse X") * 0.02f;
                 velocityY += ySpeed * Input.GetAxis("Mouse Y") * 0.02f;
 
                 if (PlayerPrefs.GetInt("FollowPlayer") == 0)
                 {
                     Vector3 position = rotation * negDistance + target.position;
                     transform.rotation = rotation;
                     transform.position = position;
                 }
 
                 if (PlayerPrefs.GetInt("FollowPlayer") == 1)
                 {
                     Vector3 position = rotation * negDistance + player.position;
                     transform.rotation = rotation;
                     transform.position = position;
                 }
             }
 
                 if (PlayerPrefs.GetInt("FollowPlayer") == 0)
                 {
                   Vector3 position = rotation * negDistance + target.position;
                   transform.position = position;
                   transform.rotation = rotation;
             }
 
                 if (PlayerPrefs.GetInt("FollowPlayer") == 1)
                 {
                   Vector3 position = rotation * negDistance + player.position;
                   transform.position = position;
                   transform.rotation = rotation;
                 }
 
             velocityX = Mathf.Lerp(velocityX, 0, Time.deltaTime * smoothTime);
             velocityY = Mathf.Lerp(velocityY, 0, Time.deltaTime * smoothTime);
         }
 
     }
 
     void Update()
     {
         if(Input.GetKeyDown("z"))
         {
             Camera.main.fieldOfView = Camera.main.fieldOfView + 1;
         }
         if (Input.GetKeyDown("x"))
         {
             Camera.main.fieldOfView = Camera.main.fieldOfView - 1;
         }
 
         if(Camera.main.fieldOfView < 30)
         {
                 PlayerPrefs.SetInt("FollowPlayer", 1);
         }
 
         if (Camera.main.fieldOfView > 30)
         {
             PlayerPrefs.SetInt("FollowPlayer", 0);
         }
     }
 
     public static float ClampAngle(float angle, float min, float max)
     {
         if (angle < -360F)
             angle += 360F;
         if (angle > 360F)
             angle -= 360F;
         return Mathf.Clamp(angle, min, max);
     }
 }