using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

namespace RimWorldAnimationStudio
{
    public class AnimationTimeline : MonoBehaviour, IPointerClickHandler
    {
        public int actorID = -1;
        public KeyframeSlider keyframeSliderPrefab;

        private Transform anchorTransform;

        private void Start()
        {
            EventsManager.onAnimationTimelinesChanged.AddListener(delegate { UpdateGUI(); });
            EventsManager.onKeyframeCountChanged.AddListener(delegate { UpdateGUI(); });                   
            EventsManager.onActorIDChanged.AddListener(delegate { UpdateTimelineSelection(); });
            EventsManager.onStageWindowSizeChanged.AddListener(delegate { UpdateGUI(); });
            EventsManager.onAnimationStageChanged.AddListener(delegate { UpdateGUI(); });

            UpdateTimelineSelection();
            UpdateGUI();
        }

        public void Initialize(int actorID)
        {
            anchorTransform = transform.parent;
            this.actorID = actorID;

            UpdateGUI();
        }

        public void ClearKeyframeSliders()
        {
            foreach (KeyframeSlider slider in GetComponentsInChildren<KeyframeSlider>())
            { Destroy(slider.gameObject); }
        }

        public void UpdateGUI()
        {
            if (actorID < 0) return;

            PawnAnimationClip clip = Workspace.GetPawnAnimationClip(actorID);
            if (clip == null) return;

            clip.BuildSimpleCurves();

            ClearKeyframeSliders();

            foreach (PawnKeyframe keyframe in clip.Keyframes)
            { AddPawnKeyFrame(keyframe.keyframeID); }

            InitiateUpdateOfGhostFrames();
        }

        public void UpdateTimelineSelection()
        {
            GetComponent<Image>().color = (Workspace.ActorID == actorID ? Constants.ColorGoldYellow : Constants.ColorMidGrey);
        }

        public void AddPawnKeyFrame(int keyframeID)
        {
            KeyframeSlider keyframeSlider = Instantiate(keyframeSliderPrefab, transform);
            keyframeSlider.Initialize(this, actorID, keyframeID);
        }

        public void RemovePawnKeyFrame(int keyframeID)
        {
            KeyframeSlider keyframeSlider = GetComponentsInChildren<KeyframeSlider>().FirstOrDefault(x => x.keyframeID == keyframeID);
            Destroy(keyframeSlider?.gameObject);
        }

        public void InitiateUpdateOfGhostFrames()
        {
            BroadcastMessage("UpdateGhostFrames");
        }

        public void OnMoveTimeline(int delta)
        {
            int? siblingIndex = anchorTransform.parent.GetComponentsInChildren<AnimationTimeline>()?.ToList()?.IndexOf(this);
            int? siblingCount = anchorTransform.parent.GetComponentsInChildren<AnimationTimeline>()?.ToList()?.Count();

            if (siblingIndex != null && siblingCount != null && MoveAnimationTimeline(siblingIndex.Value, delta))
            { AnimationController.Instance.Initialize(); }
        }

        public bool MoveAnimationTimeline(int startIndex, int delta)
        {
            if (startIndex + delta < 0 || startIndex + delta >= Workspace.GetCurrentAnimationStage().AnimationClips.Count)
            { Debug.Log("Cannot move animation timeline - movement would exceed bounds"); return false; }

            Actor actor = Workspace.animationDef.Actors[startIndex];
            Workspace.animationDef.Actors[startIndex] = Workspace.animationDef.Actors[startIndex + delta];
            Workspace.animationDef.Actors[startIndex + delta] = actor;

            foreach (AnimationStage stage in Workspace.animationDef.animationStages)
            {
                int stageID = stage.GetStageID();
                
                PawnAnimationClip clip = Workspace.GetPawnAnimationClip(stageID, startIndex);
                Workspace.GetAnimationStage(stageID).AnimationClips[startIndex] = Workspace.GetAnimationStage(stageID).AnimationClips[startIndex + delta];
                Workspace.GetAnimationStage(stageID).AnimationClips[startIndex + delta] = clip;
            }

            Workspace.ActorID = startIndex + delta;
            Workspace.RecordEvent("Timeline move");

            return true;
        }

        public void OnPointerClick(PointerEventData eventData)
        {
            Workspace.ActorID = actorID;
            Workspace.keyframeID.Clear();
        }
    }
}