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

namespace RimWorldAnimationStudio
{
    public class KeyframeSlider : Slider, IPointerClickHandler, IBeginDragHandler, IEndDragHandler
    {
        public AnimationTimeline timeline;
        public Transform ghostSliders;
        public Slider ghostSliderPrefab;
        public Image handleImage;
        public GameObject soundIcon;
        public int maxGhosts = 4;

        public int actorID;
        public int keyframeID;

        private PawnAnimationClip clip;
        private PawnKeyframe keyframe;
        private float dragTimeStart = -1f;

        public void Initialize(AnimationTimeline timeline, int actorID,  int keyframeID)
        {
            this.timeline = timeline;
            this.clip = Workspace.Instance.GetPawnAnimationClip(actorID);
            this.keyframe = Workspace.Instance.GetPawnKeyframe(actorID, keyframeID);

            this.actorID = actorID;
            this.keyframeID = keyframeID;

            PawnKeyframe keyframe = Workspace.Instance.GetPawnKeyframe(actorID, keyframeID);
            maxValue = Workspace.StageWindowSize;
            value = keyframe.atTick.Value;
           
            OnValueChanged();

            onValueChanged.AddListener(delegate (float value) { OnValueChanged(); });
        }

        public void OnValueChanged()
        {
            keyframe.atTick = (int)value;
            clip.BuildSimpleCurves();

            //AnimationController.Instance.stageTick = keyframe.atTick.Value;

            timeline.InitiateUpdateOfGhostFrames();
        }  

        // Ghost sliders are non-interactable slider handle
        public void UpdateGhostFrames()
        {
            if (maxGhosts == 0)
            { return; }

            int requiredGhosts = GetGhostFramesRequired();
            int currentGhostCount = ghostSliders.childCount;

            for (int i = 0; i < Mathf.Max(requiredGhosts, currentGhostCount); i++)
            {
                int targetTick = (int)(i * clip.duration + keyframe.atTick);

                if (ghostSliders.childCount <= i)
                { Instantiate(ghostSliderPrefab, ghostSliders); }

                GameObject ghostSliderObject = ghostSliders.GetChild(i).gameObject;
                ghostSliderObject.SetActive(i < requiredGhosts);

                Slider ghostSlider = ghostSliderObject.GetComponent<Slider>();
                ghostSlider.maxValue = Workspace.StageWindowSize;
                ghostSlider.value = targetTick;
 
                if (targetTick > ghostSlider.maxValue) 
                { ghostSlider.gameObject.SetActive(false); }
            }
        }

        public int GetGhostFramesRequired()
        {
            if (Workspace.animationDef.animationStages[Workspace.stageID].isLooping == false)
            { return 0; }

            if (clip.duration <= 1)
            { return 0; }

            return Math.Min(Mathf.CeilToInt((float)Workspace.StageWindowSize / clip.duration), maxGhosts);
        }

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

            if (eventData.clickCount >= 2)
            { AnimationController.Instance.stageTick = keyframe.atTick.Value; }

            //Workspace.Instance.RecordEvent("Keyframe selected");
        }

        public void OnBeginDrag(PointerEventData eventData)
        {
            //AnimationController.Instance.stageTick = keyframe.atTick.Value;
            Workspace.actorID = actorID;
            Workspace.keyframeID = keyframeID;

            dragTimeStart = Time.unscaledTime;
        }

        public override void OnDrag(PointerEventData eventData)
        {
            if (keyframe.atTick == 1)
            { value = 1; return; }

            if (Time.unscaledTime - dragTimeStart < 0.05f) return;

            interactable = true;
            base.OnDrag(eventData);

            //AnimationController.Instance.stageTick = keyframe.atTick.Value;
            Workspace.actorID = actorID;
        }

        public void OnEndDrag(PointerEventData eventData)
        {
            if (keyframe.atTick == 1)
            { value = 1; return; }

            interactable = false;
            Workspace.Instance.RecordEvent("Keyframe tick");
        }

        protected override void Update()
        {
            base.Update();

            if (keyframe.atTick.HasValue && Workspace.keyframeID == keyframeID && AnimationController.Instance.stageTick == keyframe.atTick.Value)
            { handleImage.color = Constants.ColorPurple; }

            else if (Workspace.keyframeID == keyframeID)
            { handleImage.color = Constants.ColorCyan; }

            else if (keyframe.atTick.HasValue && AnimationController.Instance.stageTick == keyframe.atTick.Value)
            { handleImage.color = Constants.ColorPink; }

            else
            { handleImage.color = Constants.ColorWhite; }

            string soundDef = Workspace.Instance.GetPawnKeyframe(actorID, keyframeID)?.soundEffect;

            if (soundDef != null && soundDef != "" && soundDef != "None")
            { soundIcon.SetActive(true); }

            else
            { soundIcon.SetActive(false); }
        }
    }
}