using System;
#if UNITY_EDITOR
using UnityEditor;
#endif
using UnityEngine;
using UnityEngine.Timeline;
using UnityEngine.Playables;

namespace FT.Timeline
{
    [Serializable]
    [TrackColor(0.565f, 0.753f, 0.565f)]
    [TrackClipType(typeof(SiblingOrderPlayableAsset))]
    [TrackBindingType(typeof(GameObject))]
    [ExcludeFromPreset]
    public class SiblingOrderTrack : TrackAsset
    {
        public override Playable CreateTrackMixer(PlayableGraph graph, GameObject go, int inputCount)
        {
            return ScriptPlayable<SiblingOrderBehaviour>.Create(graph, inputCount);
        }

        protected override void OnCreateClip(TimelineClip clip)
        {
            clip.displayName = "Sibling Order";
            base.OnCreateClip(clip);
        }

#if UNITY_EDITOR
        public override void GatherProperties(PlayableDirector director, IPropertyCollector driver)
        {
            var boundObject = director.GetGenericBinding(this) as GameObject;
            if (boundObject != null)
            {
                var clips = GetClips();
                foreach (var clip in clips)
                {
                    var playableAsset = clip.asset as SiblingOrderPlayableAsset;
                    if (playableAsset != null && playableAsset.children.Count == 0)
                    {
                        RefreshChildren(playableAsset, boundObject);
                    }
                }
            }
            base.GatherProperties(director, driver);
        }

        public void RefreshChildren(SiblingOrderPlayableAsset playableAsset, GameObject boundObject)
        {
            if (playableAsset == null || boundObject == null) return;

            playableAsset.children.Clear();
            int childCount = boundObject.transform.childCount;
            for (int i = 0; i < childCount; i++)
            {
                var child = boundObject.transform.GetChild(i).gameObject;
                var exposedRef = new ExposedReference<GameObject> { defaultValue = child };
                exposedRef.exposedName = GUID.Generate().ToString();
                playableAsset.children.Add(exposedRef);

                var director = boundObject.GetComponent<PlayableDirector>();
                if (director != null)
                {
                    director.SetReferenceValue(exposedRef.exposedName, child);
                }
            }
        }
#endif
    }
}