CharacterStateMachine.cs

public class CharacterStateMachine : StateMachine<Character, CharacterState>
{
    public CharacterStateMachine(Character context) : base(context) { }

    public CharacterState IdlingState { get; private set; }
    public CharacterState WalkingState { get; private set; }
    public CharacterState RunningState { get; private set; }
    public CharacterState JumpingState { get; private set; }
    public CharacterState FallingState { get; private set; }

    public override void Awake()
    {
        base.Awake();

        IdlingState = new IdlingCharacterState(Context);
        WalkingState = new WalkingCharacterState(Context);
        RunningState = new RunningCharacterState(Context);
        JumpingState = new JumpingCharacterState(Context);
        FallingState = new FallingCharacterState(Context);
    }

    public override void Start()
    {
        base.Start();

        SwitchState(IdlingState);
    }

    public override void FixedUpdate()
    {
        base.FixedUpdate();

        if (Context.IsGrounded())
        {
            if (Context.JumpCallbackContext > 0f)
            {
                SwitchState(JumpingState);
            }
            else
            {
                SwitchState(IdlingState);
            }
        }
        else
        {
            SwitchState(FallingState);
        }

        if (Context.WalkCallbackContext.magnitude != 0f)
        {
            if (Context.RunCallbackContext > 0f)
            {
                SwitchState(RunningState);
            }
            else
            {
                SwitchState(WalkingState);
            }
        }
    }
}