some behavior on over-shoulder view and static var in update()

Hi, my game use third-person view.And in normal state camera will always follow player back.Now I have some problem in makeing the aim state. the situation is

• When player press RMB,camera will move to over-shoulder view.(during this process,player can't move)

• After camera reach the desired position, fix the camera view to player(which means camera always follow player in fixed position, now is lower left-corner on screen).

• Then recover the player movement ability and mouse look.

• Once release RMB, camera convert to normal view.

My problem is I use lerp to smooth camera when it convert to over-shoulder view.It seems to update every frame.I am not sure that how to realize that : If camera reached the over-shoulder view position,stop update the smooth function.I also has problem in getting variable from other script.Now I create one function to check the current distance and wanted distance of camera.If it didn't reached desired distance, use first follow function.Else use second follow function.I also create a ` static var canmove which can be accessed by playercontrolscript.The playerconrolscipt get the variable and change walk speed . But the variable in playercontrolscript seems not update every frame following my camera script variable.

I tried a lot method but still not work well.....Can someone give me any idea? Thanks..

edit (copied from comment and fixed indent)

 var target : Transform; 
 
 var xSpeed = 250.0;
 var ySpeed = 120.0;
 
 var yMinLimit = -20;
 var yMaxLimit = 80;
 
 var initDis = 10;
 var minDis = 2.0;
 var maxDis = 10.0;
 
 var currentdis ;
 var wheelSpeed = 5;
 
 static var x = 0.0;
 static var y = 0.0;
 
 static  var distance =5.0;
 var fixdis;
 private var position;
 private var rotation;
 var changeonce = 0;
 
 
 static var IsMoving =1;
 
 function Start ()
 {
     x = 30;
     y = 0;
     if (rigidbody)
         rigidbody.freezeRotation = true;
 }
 
 private var smoothTime = 0.5;
 private var velocity = 0.0;
 
 private var onetime = 0;
 
 function Update () 
 {
     if (target) 
     {
         checkdis();
         currentdis = Vector3.Distance(target.position,transform.position);
  
         if(Input.GetMouseButton(1))
         {
             print("fixdis"+fixdis);
             
             if ((currentdis-fixdis)>0.07)
             {
                 IsMoving = 1;  //check if camera position approach the over-shoulder view
                 Overshoulder();
                 print("currentdis"+currentdis);
             }
             else if((currentdis-fixdis)<=0.07)
         {
                 IsMoving = 0;
                 print("Moving false");
                 
                 x += Input.GetAxis("Mouse X") * xSpeed * 0.02;
                 y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02;
                 
                 y = ClampAngle(y, yMinLimit, yMaxLimit);
                 
                 rotation = Quaternion.Euler(y, x-10, 0);
                 position = rotation * Vector3(0.3, 1.8, -1.2)+ target.position;
                 transform.rotation = rotation;
                 transform.position= position;
                 target.rotation = Quaternion.Euler(0,x,0);
             }
         }
         else
         {
             x += Input.GetAxis("Mouse X") * xSpeed * 0.02;
             y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02;
             y = ClampAngle(y, yMinLimit, yMaxLimit);
             
             rotation = Quaternion.Euler(y, x, 0);
             position = rotation * Vector3(0.5, 1.5, -2)+ target.position;
             
             transform.rotation = rotation;
             transform.position= position;
             target.rotation = Quaternion.Euler(0,x,0);
         }
     }
 }
 
 static function ClampAngle (angle : float, min : float, max : float)
 {
     if (angle < -360)
         angle += 360;
     if (angle > 360)
         angle -= 360;
     return Mathf.Clamp (angle, min, max);
 }
 
 function checkdis()
 {
     if(changeonce == 0)
     {
         rotation = Quaternion.Euler(y, x-15, 0);
         position = rotation * (Vector3(0.3, 1.8, -1.2) ) + target.position;
         fixdis = Vector3.Distance(target.position,position);
         changeonce = 1;
     }
 }
 
 //smooth the camera moving to overshoulder view
 function Overshoulder()
 {
     rotation = Quaternion.Euler(y, x-15, 0);
     position = rotation * (Vector3(0.3, 1.8, -1.2) ) + target.position;
     
     var newY = Mathf.SmoothDamp(0, position.x - transform.position.x, velocity, smoothTime);
     var factor = newY / (position.x - transform.position.x);
     
     transform.position += Vector3(Mathf.Lerp(0, position.x - transform.position.x, factor),
                                   Mathf.Lerp(0, position.y - transform.position.y, factor),
                                   Mathf.Lerp(0, position.z - transform.position.z, factor));
 }