Unity: Changing direction character faces when using InputManager(side scroller) - animation

Question

I'm creating a simple side scroller with a couple people using Unity and am definitely a beginner. The character being used is 3D and runs forward well, but when running backwards he still faces forward. I have the controls setup in the InputManager so pressing A moves backwards and D moves forward but I'm not sure what to do so he faces his respective movement.
Any help would be greatly appreciated and if you need more information besides the following code I have for the movement let me know, it's based off another post I found.
var speed : float = 6.0;
var jumpSpeed : float = 6.0;
var gravity : float = 12.0;
//This variable is now inheriting the Vector3 info (X,Y,Z) and setting them to 0.
private var moveDirection : Vector3 = Vector3.zero;
function MoveAndJump() {
var controller : CharacterController = GetComponent(CharacterController);
if(controller.isGrounded) {
//moveDirection is inheriting Vector3 info. This now sets the X and Z coords to receive the input set to "Horizontal" and "Vertical"
moveDirection = Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical")); //Allows player Input
moveDirection = transform.TransformDirection(moveDirection); //How to move
moveDirection *= speed; //How fast to move
if(Input.GetButtonDown("Jump")) {
animation.Play("Jump");
moveDirection.y = jumpSpeed;
}
}
//Apply gravity
moveDirection.y -= gravity * Time.deltaTime;
//This moves the controller
controller.Move(moveDirection * Time.deltaTime);
if(Input.GetButton("Fire1")){
animation.Play("Attack");
}
if(Input.GetButton("Vertical")){
animation.Play("Run");
}
}
function Update() {
MoveAndJump();
}
For what it's worth another problem I'm having involves having two different animations being able to work at the same time, like run and attack. I figured I should mention while I'm here if anybody knew how to go about that. Thank you again for your time!

Answer 1

I ended up solving this based off a different code I stumbled upon, then called the function inside of Update():
var speed : float;
var jumpSpeed : float;
var gravity : float;
private var moveDirection : Vector3 = Vector3.zero;
function MoveJumpAttack() {
var controller : CharacterController = GetComponent(CharacterController);
if (controller.isGrounded) {
moveDirection = Vector3(Input.GetAxis("Horizontal"), 0, 0);
moveDirection *= speed;
if (moveDirection.sqrMagnitude > 0.01)
transform.rotation = Quaternion.Slerp (transform.rotation, Quaternion.LookRotation (moveDirection), 90);
}
moveDirection.y -= gravity * Time.deltaTime;
controller.Move(moveDirection * Time.deltaTime);
}