using FlaxEngine;
using Cabrito;
using System.Diagnostics;

namespace Game
{
    public class CameraMovement : Script
    {
        [Limit(0, 9000), Tooltip("Camera speed")]
        public float MoveSpeed { get; set; } = 400;

        private float _pitch;
        private float _yaw;

        private float xAxis;
        private float yAxis;
        private float inputH;
        private float inputV;

        private InputEvent onExit = new InputEvent("Exit");

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

            onExit.Triggered += () =>
            {
                if (Console.IsSafeToQuit)
                    Engine.RequestExit();
            };
        }

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

            onExit.Dispose();
		}

        public override void OnStart()
        {
            var initialEulerAngles = Actor.Orientation.EulerAngles;
            _pitch = initialEulerAngles.X;
            _yaw = initialEulerAngles.Y;
        }

        public override void OnUpdate()
        {
            var camTrans = Actor.Transform;

            xAxis = InputManager.GetAxis("Mouse X");
            yAxis = InputManager.GetAxis("Mouse Y");

            if (xAxis != 0.0f || yAxis != 0.0f)
            {
                _pitch += yAxis;
                _yaw += xAxis;

                camTrans.Orientation = Quaternion.Euler(_pitch, _yaw, 0);
            }

            inputH = InputManager.GetAxis("Horizontal");
            inputV = InputManager.GetAxis("Vertical");
            var move = new Vector3(inputH, 0.0f, inputV);

            if (!move.IsZero)
            {
                move.Normalize();
                move = camTrans.TransformDirection(move) * MoveSpeed;
                
                {
                    Vector3 delta = move * Time.UnscaledDeltaTime;
                    float movementLeft = delta.Length;

                    // TODO: check multiple times in case we get stuck in walls

                    float sphereRadius = 10.0f; // TODO: use collider radius
                    RayCastHit[] hitInfos;
                    float moveDist = delta.Length;
                    Physics.SphereCastAll(Actor.Transform.Translation, sphereRadius, move.Normalized, out hitInfos, moveDist);

                    //bool nohit = true;
                    float hitDistance = moveDist;
                    Vector3 hitNormal = move.Normalized;
                    foreach (RayCastHit hitInfo in hitInfos)
                    {
                        if (hitInfo.Collider.Parent == Parent)
                            continue;

                        if (hitInfo.Distance < hitDistance)
                        {
                            hitDistance = hitInfo.Distance;
                            hitNormal = hitInfo.Normal;
                        }
                        //nohit = false;
                        //break;
                    }

                    if (hitDistance != moveDist)
                    {
                        //camTrans.Translation = Vector3.Lerp(Actor.Transform.Translation, camTrans.Translation, hitDistance);

                        //projected = normal * dot(direction, normal);
                        //direction = direction - projected


                        //camTrans.Translation += hitNormal * (moveDist - hitDistance); // correct?
                        //camTrans.Translation = hitNormal * (move * hitNormal); // correct?
                        //camTrans.Translation = Actor.Transform.Translation;
                        delta += -Vector3.Dot(delta, hitNormal) * hitNormal; // correct?
                    }

                    camTrans.Translation += delta;
                    
                }
            }

            Actor.Transform = camTrans;
        }
    }
}