About mecanim and changing animations, there must be more clever way of doing this.

I'm trying to learn Mecanim, and it's going pretty well other than I'm having hard time to understand which would be best way to change animations. Currently I'm using boolean parameters on Animator and Input.GetKey on my code, but this my way has f*uckloads of If statements. So, a better way of doing this would be appreciated.

Also, I'm having problem with my jump animation. After jumping it won't get back to idle animation, it just stays in end pose of jumping animation, even though I have transitions back to Idle from Jump. All other animations do get back to idle animation after I stop pressing the right key.

Here's my current code, (if statements for animations start pretty much right after function Update) Sorry about spaghetti code, there's not much of comments to explain what happens where (except the parts that has something to do with animations)

 var mainCam : GameObject;
 //Old animation stuff, not needed
 // var animObject : GameObject;
 // var fallAnimGO : GameObject;
 var moveSpeed : int = 2;
 var crouchSpeed : int = 1;
 var runSpeed : int = 5;
 var jumpSpeed : int = 10;
 var gravity : int = 20;
 var maxEnergy : float = 10;
 var energyRegenRate : float = 1;
 var Smooth : float = 5;
 
 var grounded : boolean = false;
 var running : boolean = false;
 
 var energy : float;
 private var originalSpeed : int;
 private var hitCeiling : boolean = false;
 public var moveDirection = Vector3.zero;
 private var controller : CharacterController;
 controller = GetComponent(CharacterController);
 
 private var IntialPosition : Vector3;
 private var InitialHeight : float;
 private var CrouchingHeight : float;
 private var InitialCenter : Vector3;
 private var CrouchingCenter : Vector3;
 private var defCamPos : float = 0;
 private var bobSpeed : float;
 private var bobAmount : float;
 private var timer = 0.0;
 private var camPos : float;
 private var crouching = false;
 
 internal var animator : Animator; //Mecanim animator
 
 function Start()
 {
     originalSpeed = moveSpeed;
     energy = maxEnergy;
     defCamPos = mainCam.transform.localPosition.y;
     camPos = defCamPos;
     InitialHeight = controller.height;
     CrouchingHeight = InitialHeight - .5f;
     InitialCenter = controller.center;
     CrouchingCenter = InitialCenter + Vector3.down * 0.25f;
     isCrouching = false;
     animator = GetComponent(Animator);
 }
 
 function Awake()
 {
     //Old animation stuff, not needed
     //animObject.animation.wrapMode = WrapMode.Loop;
 }
 
 function Update()
 {
     if(controller.isGrounded)
     {
         moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
         moveDirection = transform.TransformDirection(moveDirection);
         moveDirection *= moveSpeed;
         
         //Setting up mecanim animations
         //Jumping animation
         if(Input.GetKeyDown(KeyCode.Space))
         {
             animator.SetBool("jump", true);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", false);
             Jump();
         }
         
         if(Input.GetKeyUp(KeyCode.Space))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", true);
         }
         //Walking animation
         if (Input.GetKey(KeyCode.W))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", true);
             animator.SetBool("idle", false);
         }
         
         if (Input.GetKeyUp(KeyCode.W))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", true);
         }
         // Running animation
         if(Input.GetKey(KeyCode.LeftShift) && Input.GetKey(KeyCode.W))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", true);
             animator.SetBool("walk", false);
             animator.SetBool("idle", false);
         }
         
         if(Input.GetKeyUp(KeyCode.LeftShift) && Input.GetKeyUp(KeyCode.W))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", true);
         }
         //Backwards walking
         if (Input.GetKey(KeyCode.S))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", true);
             animator.SetBool("idle", false);
         }
         
         if (Input.GetKeyUp(KeyCode.S))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", true);
         }
         //If LeftShift & S down, play running animation
         if(Input.GetKey(KeyCode.LeftShift) && Input.GetKey(KeyCode.S))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", true);
             animator.SetBool("walk", false);
             animator.SetBool("idle", false);
         }
         //If LeftShift & S up, don't play running animation
         if(Input.GetKeyUp(KeyCode.LeftShift) && Input.GetKeyUp(KeyCode.S))
         {
             animator.SetBool("jump", false);
             animator.SetBool("run", false);
             animator.SetBool("walk", false);
             animator.SetBool("idle", true);
         }
         
         if(controller.velocity.magnitude > (moveSpeed - 1) && controller.velocity.magnitude < (runSpeed - 1))
         {
             //Old animation stuff, not needed
             //animObject.animation.CrossFade("Walk");
             bobSpeed = 0.25;
             bobAmount = 0.005;
             
         }
         else if(controller.velocity.magnitude > (runSpeed - 1))
         {
             //Old animation stuff, not needed
             //animObject.animation.CrossFade("Run");
             bobSpeed = 0.29;
             bobAmount = 0.01;
         }
         else
         {
             bobSpeed = 0;
             bobAmount = 0;
         }
         if(Input.GetKey(KeyCode.LeftShift) && (Input.GetAxis("Horizontal") || Input.GetAxis("Vertical")))
         {
             if(energy > 0)
             {
                 if(!crouching)
                 {
                     Run();
                 }
                 else
                 {
                     moveSpeed = crouchSpeed;
                 }
             }
             else
             {
                 running = false;
                 if(!crouching)
                 {
                     moveSpeed = originalSpeed;
                 }
                 else
                 {
                     moveSpeed = crouchSpeed;
                 }
             }
         }
         else
         {
             running = false;
             if(energy < maxEnergy)
             {
                 energy += energyRegenRate * Time.deltaTime;
             }
             if(!crouching)
             {
                 moveSpeed = originalSpeed;
             }
             else
             {
                 moveSpeed = crouchSpeed;
             }
         }
         
         var camHeight : Vector3 = new Vector3(mainCam.transform.localPosition.x, camPos, mainCam.transform.localPosition.z);
         var smoothHeight  = Vector3.Lerp(mainCam.transform.localPosition, camHeight, Time.deltaTime * Smooth);
         mainCam.transform.localPosition = smoothHeight;
         
         if(Input.GetKeyDown("c"))
         {
             if(!crouching)
             {
                 controller.height = CrouchingHeight;
                 controller.center = CrouchingCenter;
                 camPos = defCamPos - .5f;
                 crouching = true;
             }
             else
             {
                 controller.height = InitialHeight;
                 controller.center = InitialCenter;
                 camPos = defCamPos;
                 crouching = false;
             }
         }
         waveslice = 0.0; 
         horizontal = Input.GetAxis("Horizontal"); 
         vertical = Input.GetAxis("Vertical"); 
         if(Mathf.Abs(horizontal) == 0 && Mathf.Abs(vertical) == 0) { 
               timer = 0.0; 
         } 
         else
         { 
                waveslice = Mathf.Sin(timer); 
                timer = timer + bobSpeed; 
                if(timer > Mathf.PI * 2)
                { 
                   timer = timer - (Mathf.PI * 2); 
                } 
         } 
         if(waveslice != 0)
         { 
                translateChange = waveslice * bobAmount; 
                totalAxes = Mathf.Abs(horizontal) + Mathf.Abs(vertical); 
                totalAxes = Mathf.Clamp (totalAxes, 0.0, 1.0); 
                translateChange = totalAxes * translateChange; 
                mainCam.transform.localPosition.y = smoothHeight.y + translateChange; 
         } 
         else
         { 
            mainCam.transform.localPosition.y = smoothHeight.y; 
         } 
     }
     else
     {
         //Old animation stuff, not needed
         //animObject.animation.CrossFade("Idle");
         animator.SetBool("idle", true);
         bobSpeed = 0;
         bobAmount = 0;
     }
     moveDirection.y -= gravity * Time.deltaTime;
     if(hitCeiling)
     {
         moveDirection.y -= gravity * Time.deltaTime;
     }
     var flags = controller.Move(moveDirection * Time.deltaTime);
     hitCeiling = ((flags & CollisionFlags.CollidedAbove) != 0);
     if(energy > maxEnergy)
     {
         energy = maxEnergy;
     }
 }
 
 function Run()
 {
     moveSpeed = runSpeed;
     energy -= energyRegenRate * Time.deltaTime;
     running = true;
 }
 
 function Jump()
 {
     moveDirection.y = jumpSpeed;
     //Old animation stuff, not needed
     //fallAnimGO.animation.CrossFadeQueued("Jump", 0.1, QueueMode.PlayNow);
 }
 
 function OnControllerColliderHit(Hit : ControllerColliderHit)
 {
     if(!controller.isGrounded && controller.velocity.y < -6)
     {
         //Old animation stuff, not needed    
         //fallAnimGO.animation.CrossFadeQueued("Fall", 0.3, QueueMode.PlayNow);
     }
 }