using UnityEngine;
using System.Collections;

public class MovementController : MonoBehaviour
{
    public float
        deadZoneValue = 0.1f,
        angle,
        acceleration  = 50.0f;
    public Vector3
        motion ;
    public Vector3
        ground_direction ;

//--------------------------------------------------------------------------------------------
    void OnGUI()
    {
        GUILayout.Label( "transform.rotation : " + transform.rotation );
        GUILayout.Label( "transform.position : " + transform.position );
        GUILayout.Label( "angle : " + angle );
        GUILayout.Label( "ground_direction : " + ground_direction );
        GUILayout.Label( "motion : " + ground_direction );
    }

    void FixedUpdate ()
    {

        Ray
            ground_check_ray = new Ray( gameObject.transform.position, -gameObject.transform.up );
        RaycastHit
            raycast_result;
        Rigidbody
            rigid_body = gameObject.rigidbody;

        if ( Physics.Raycast( ground_check_ray, out raycast_result ) )
        {
            Vector3
                next_position;

            //UpdateOrientation( gameObject.transform.forward, raycast_result.normal );
            UpdateOrientation( gameObject.transform.forward, raycast_result.normal );
            next_position = GetNextPosition( raycast_result.point );
            rigid_body.MovePosition( next_position );
            ground_direction = raycast_result.normal;
        }
    }
//--------------------------------------------------------------------------------------------


    private void UpdateOrientation( Vector3 forward_vector, Vector3 ground_normal )
    {
        Vector3
            projected_motion_to_normal_surface = motion - ( Vector3.Dot( motion, ground_normal ) ) * ground_normal;

        Quaternion target;
        if (motion.sqrMagnitude > 0)
        {
            target = Quaternion.LookRotation( projected_motion_to_normal_surface, ground_direction );
        }
        else
        {
            target = Quaternion.LookRotation( transform.forward, ground_direction );
        }
        transform.rotation  = Quaternion.Slerp( transform.rotation, target, 0.1f );
        //transform.rotation = Quaternion.LookRotation( projected_forward_to_normal_surface, ground_normal );
    }

    private Vector3 GetNextPosition( Vector3 current_ground_position )
    {
        Vector3
            next_position;

//      //--------------------------------------------------------------------
//      angle = 0;
//      Vector3 dir = this.transform.InverseTransformDirection(motion);
//      angle = Vector3.Angle(Vector3.forward, dir);// * 1f * Time.fixedDeltaTime;
//
//      if(angle > 0) this.transform.Rotate(0,angle,0);
//      //--------------------------------------------------------------------


        next_position =
            current_ground_position +
            gameObject.transform.up * 0.5f
                + motion
                ;

        return next_position;
    }

}