using System;
using System.Collections;
using UnityEngine;
using Random = UnityEngine.Random;

namespace MAVRIC.GEEKCup.Portraits
{
    public class LookAtCamera : MonoBehaviour
    {
        
        private Transform lookTarget;


        private Vector3 lookGoal;
        
        public float maxLookDiff = 0.5f;
        public float randLookSpeedMin = 0.1f;
        public float randLookSpeedMax = 1.0f;
        public float randMinChangeLook = 0.2f;
        public float randMaxChangeLook = 2.0f;

        private void Start()
        {
            StartCoroutine(WaitForCamera());

            IEnumerator WaitForCamera()
            {
                while (Camera.main == null) yield return null;
                lookTarget = Camera.main.transform;
                StartCoroutine(Looking());
            }
        }

        private IEnumerator Looking()
        {
            while (true)
            {
                yield return null;

                int randDirection = Random.Range(0, 3);
                float randSpeed = Random.Range(randLookSpeedMin, randLookSpeedMax);
                float randAngle = Random.Range(0, maxLookDiff);

                Vector3 goal = lookTarget.position;

                Quaternion startRot = transform.localRotation;
                
                switch (randDirection)
                {
                    case 0:
                        goal += lookTarget.right * randAngle;
                        break;
                    case 1:
                        goal += lookTarget.up * randAngle;
                        break;
                    case 2:
                        goal -= lookTarget.right * randAngle;
                        break;
                    case 3:
                        goal -= lookTarget.up * randAngle;
                        break;
                    default:
                        break;
                }
                
                transform.LookAt(goal);

                Quaternion lookRot = transform.localRotation;

                transform.localRotation = startRot;

                for (float timer = 0; timer < randSpeed; timer += Time.deltaTime)
                {
                    float percent = timer / randSpeed;
                    transform.localRotation = Quaternion.Lerp(startRot, lookRot, percent);
                    yield return null;
                }
                transform.localRotation = lookRot;

                yield return new WaitForSeconds(Random.Range(randMinChangeLook, randMaxChangeLook));
            }
        }
    }
}