Mouse Orbit Script Help

First off I'm not a coder or scripter by any means and i cannot imagine why something this basic isnt built in.

So, I have the Mouse Orbit script working. While playing I can freely move the mouse to rotate the camera. The script is attached to the camera. However there are a few pretty basic things I want to do but simply cannot figure out.

When I finally get this code working I will freely upload it to the asset store for anyone to use. Cause this is basic 3rd person game shit.

1. I want the mouse orbit cam to only run while I hold Left Click

2. When I release Left Click, I want the camera to stay where it was until there is a movement input, then the camera would re-align behind the character.

3. I want to offset the camera slightly to the right of my target

Here is the current code I found on the internet:

     using UnityEngine;
     using System.Collections;
 
     [AddComponentMenu("Camera-Control/Mouse Orbit with zoom")]
     public class MouseOrbitImproved : MonoBehaviour
     {
     public Transform target;
     public float distance = 5.0f;
     public float xSpeed = 120.0f;
     public float ySpeed = 120.0f;
 
     public float yOffset = 1;
 
     public float yMinLimit = -20f;
     public float yMaxLimit = 80f;
 
     public float distanceMin = .5f;
     public float distanceMax = 15f;
 
     private Rigidbody rigidbody;
 
     float x = 0.0f;
     float y = 0.0f;
 
     // Use this for initialization
     void Start()
     {
         Vector3 angles = transform.eulerAngles;
         x = angles.y;
         y = angles.x;
 
         rigidbody = GetComponent<Rigidbody>();
 
         // Make the rigid body not change rotation
         if (rigidbody != null)
         {
             rigidbody.freezeRotation = true;
         }
     }
 
     void LateUpdate()
     {
         if (target)
         {
 
             x += Input.GetAxis("Mouse X") * xSpeed * distance * 0.02f;
             y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f;
 
             y = ClampAngle(y, yMinLimit, yMaxLimit);
 
             Quaternion rotation = Quaternion.Euler(y, x, 0);
 
             distance = Mathf.Clamp(distance - Input.GetAxis("Mouse ScrollWheel") * 5, distanceMin, distanceMax);
 
             RaycastHit hit;
             if (Physics.Linecast(target.position, transform.position, out hit))
             {
                 distance -= hit.distance;
             }
             Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
             Vector3 position = rotation * negDistance + target.position + new Vector3(0, yOffset, 0);
 
             transform.rotation = rotation;
             transform.position = position;
         }
     }
 
     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);
     }
 }
   

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