using System.Collections.Generic;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;
#endif
using System.Linq;

#if HDRP_IS_INSTALLED_FOR_UTS
using UnityEngine.Rendering.HighDefinition;

namespace Unity.Rendering.HighDefinition.Toon
{
    [ExecuteAlways]
    [DisallowMultipleComponent]
    [RequireComponent(typeof(Light))]
    internal class BoxLightAdjustment : MonoBehaviour
    {
        private bool _initialized = false;
        private bool _srpCallbackInitialized = false;

        [SerializeField]
        private GameObject[] _gameObjects;

        [SerializeField]
        private Renderer[] _renderers;

        [SerializeField]
        internal HDAdditionalLightData targetBoxLight;

        [SerializeField]
        internal bool followGameObjectPosition = false;

        [SerializeField]
        internal bool followGameObjectRotation = false;
        [SerializeField]
        internal Vector3 positionOffset;
        [SerializeField]
        internal Quaternion rotationOffset;
#if UNITY_EDITOR
#pragma warning restore CS0414
        private bool _isCompiling = false;
#endif

        private void Reset()
        {
            OnDisable();
            OnEnable();
        }

        internal void OnValidate()
        {
            Release();
            Initialize();
        }

        private void Awake()
        {
            Initialize();

        }
        // Start is called before the first frame update
        private void Start()
        {

        }

        // Update is called once per frame
        private void Update()
        {
            Initialize();

#if UNITY_EDITOR
            // handle script recompile
            if (EditorApplication.isCompiling && !_isCompiling)
            {
                // on compile begin
                _isCompiling = true;
                //                Release(); no need
                return; // 
            }
            else if (!EditorApplication.isCompiling && _isCompiling)
            {
                // on compile end
                _isCompiling = false;
            }
#endif
            if (_renderers == null)
            {
                return;
            }
            if (targetBoxLight == null)
            {
                return;
            }

            // TODO: Set rendering layer mask when property changed.
            for (var ii = 0; ii < _renderers.Length; ii++)
            {
                _renderers[ii].renderingLayerMask &= 0xffffff00;
                _renderers[ii].renderingLayerMask |= (uint)targetBoxLight.lightlayersMask;
            }

            if (_gameObjects != null && _gameObjects.Length > 0 && _gameObjects[0] != null)
            {
                if (followGameObjectPosition)
                {
                    targetBoxLight.transform.position = _gameObjects[0].transform.position + positionOffset;
                }
                if (followGameObjectRotation)
                {
                    targetBoxLight.transform.rotation = _gameObjects[0].transform.rotation * rotationOffset;
                }
            }
        }

        private void EnableSrpCallbacks()
        {

            if (!_srpCallbackInitialized)
            {
                _srpCallbackInitialized = true;
            }
        }

        private void DisableSrpCallbacks()
        {
            if (_srpCallbackInitialized)
            {
                _srpCallbackInitialized = false;
            }
        }

        private void OnEnable()
        {
            Initialize();

            EnableSrpCallbacks();
        }


        private void OnDisable()
        {
            DisableSrpCallbacks();

            Release();
        }

        private void UpdateObjectLightLayers()
        {
            Initialize();
        }

        internal static GameObject CreateBoxLight(GameObject[] gameObjects)
        {
            if (gameObjects == null || gameObjects[0] == null)
            {
                Debug.LogError("Please, select a GameObject you want a Box Light to follow.");
                return null;
            }
            var gameObjectName = "Box Light for " + gameObjects[0].name;
            var lightGameObject = new GameObject(gameObjectName);
#if UNITY_EDITOR
            Undo.RegisterCreatedObjectUndo(lightGameObject, "Created Boxlight adjustment");
#endif
            var hdLightData = lightGameObject.AddHDLight(LightType.Box);
            // light size
            hdLightData.SetBoxSpotSize(new Vector2(10.0f, 10.0f)); // Size should be culculated with more acculacy?
            var boxLightAdjustment = lightGameObject.GetComponent<BoxLightAdjustment>();
            if (boxLightAdjustment == null)
            {
#if UNITY_EDITOR
                boxLightAdjustment = Undo.AddComponent<BoxLightAdjustment>(lightGameObject);
#else
                boxLightAdjustment = lightGameObject.AddComponent<BoxLightAdjustment>();
#endif
            }



#if UNITY_EDITOR
            Undo.RecordObject(boxLightAdjustment, "target " + boxLightAdjustment.name);
#endif
            boxLightAdjustment.targetBoxLight = hdLightData;
#if UNITY_EDITOR
            Undo.RecordObject(lightGameObject.transform, "Position " + lightGameObject.transform.name);
#endif
            // position and rotation
            var goPos = lightGameObject.transform.position;
            goPos.y += 10.0f;
            lightGameObject.transform.position = goPos;

            var goRot = lightGameObject.transform.rotation;
            goRot.eulerAngles = new Vector3(90.0f, 0.0f, 0.0f);
#if UNITY_EDITOR
            Undo.RecordObject(lightGameObject.transform, "Rotation " + lightGameObject.transform.name);
#endif
            hdLightData.gameObject.transform.rotation = goRot;

            // must be put to gameObject model chain.
            boxLightAdjustment._gameObjects = gameObjects;


            return lightGameObject;
        }


        private void Initialize()
        {
            if (_initialized)
            {
                return;
            }
#if UNITY_EDITOR
            // initializing renderer can interfere GI baking. so wait until it is completed.

            if (EditorApplication.isCompiling)
                return;
#endif
            if (_gameObjects == null)
            {
                return;
            }
            var objCount = _gameObjects.Length;
            var rendererCount = 0;

            var rendererList = new List<Renderer>();
            for (var ii = 0; ii < objCount; ii++)
            {
                if (_gameObjects[ii] == null)
                {
                    continue;
                }


                var renderer = _gameObjects[ii].GetComponent<Renderer>();
                if (renderer != null)
                {
                    rendererCount++;
                    rendererList.Add(renderer);
                }

                var childGameObjects = _gameObjects[ii].GetComponentsInChildren<Transform>().Select(t => t.gameObject).ToArray();
                var childCount = childGameObjects.Length;
                for (var jj = 0; jj < childCount; jj++)
                {
                    if (_gameObjects[ii] == childGameObjects[jj])
                    {
                        continue;
                    }

                    var modelToonEvAdjustment = childGameObjects[jj].GetComponent<BoxLightAdjustment>();
                    if (modelToonEvAdjustment != null)
                    {
                        break;
                    }

                    renderer = childGameObjects[jj].GetComponent<Renderer>();
                    if (renderer == null)
                    {
                        continue;
                    };

                    rendererList.Add(renderer);
                    rendererCount++;
                }
                if (rendererCount != 0)
                {
                    _renderers = rendererList.ToArray();
                }
            }
            if (targetBoxLight != null && objCount > 0)
            {
                positionOffset = targetBoxLight.transform.position - _gameObjects[0].transform.position;
                rotationOffset = Quaternion.Inverse(_gameObjects[0].transform.rotation) * targetBoxLight.transform.rotation;
            }

            _initialized = true;
        }

        private void Release()
        {
            if (_initialized)
            {
                _renderers = null;
            }

            _initialized = false;

        }
    }
}
#endif  // HDRP_IS_INSTALLED_FOR_UTS