using System;
using System.Text;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using System.Xml.Serialization;
using UnityEngine;
using SFB;
using UnityEngine.UI;

namespace RimWorldAnimationStudio
{
    public class AnimationController : Singleton<AnimationController>
    {
        [Header("Animation settings")]
        public bool isAnimating = false;
        public int stageTick = 1;

        [Header("Object references")]
        public Slider stageTimelineSlider;
        public Dropdown stageLoopDropdown;
        public InputField cyclesNormalField;
        public InputField cyclesFastField;
        public InputField animationClipTimeField;
        public InputField animationClipLengthField;
        public ActorCard actorCard;
        public Transform animationTimelines;       

        [Header("Prefabs")]
        public ActorBody actorBodyPrefab;
        public AnimationTimeline animationTimelinePrefab;

        // Private timing variables
        private int lastStageTick = 1;
        private float timeSinceLastUpdate = 0;
        private int cycleIndex = 0;
        
        public void Update()
        {
            // No animation, exit
            if (Workspace.animationDef == null) { return; }

            // Dirty animation, reset
            if (Workspace.animationDef != null && Workspace.isDirty)
            { Initialize(); return; }

            // Update tick if animating
            if (isAnimating)
            {
                timeSinceLastUpdate += Time.deltaTime;

                if (timeSinceLastUpdate < 1f / 60f)
                { return; }

                timeSinceLastUpdate -= 1f / 60f;
                stageTick += 1;

                if (stageTick > Workspace.StageWindowSize)
                {
                    if (stageLoopDropdown.value == 1)
                    { stageTick = 1; }

                    else if (stageLoopDropdown.value >= 2 && Workspace.stageID < Workspace.animationDef.animationStages.Count - 1)
                    {
                        ++cycleIndex;
                        stageTick = 1;

                        if ((stageLoopDropdown.value == 2 && cycleIndex > int.Parse(cyclesNormalField.text)) || 
                            (stageLoopDropdown.value == 3 && cycleIndex > int.Parse(cyclesFastField.text)))
                        {
                            ++Workspace.stageID;
                            cycleIndex = 0;

                            //ResetAnimationTimeline();
                            //InitializeAnimationTimeline();
                        }
                    }

                    else
                    { stageTick = Workspace.StageWindowSize; }
                }
            }

            // Update stage timeline
            animationClipTimeField.interactable = isAnimating == false;
            animationClipLengthField.interactable = isAnimating == false;

            if (lastStageTick != stageTick)
            {
                stageTimelineSlider.value = stageTick;
                animationClipTimeField.text = stageTick.ToString();
                
                lastStageTick = stageTick;
            }

            // Update animation
            UpdateAnimation();
        }

        public void UpdateAnimation()
        {
            if (Workspace.Instance.AnimationTimelinesNeedUpdate())
            {
                ResetAnimationTimeline();
                InitializeAnimationTimeline();
            }

            List<ActorBody> actorBodies = GetComponentsInChildren<ActorBody>().ToList();

            for (int actorID = 0; actorID < actorBodies.Count; actorID++)
            {
                PawnAnimationClip clip = Workspace.animationDef?.animationStages[Workspace.stageID]?.animationClips[actorID];
                
                if (clip == null)
                { continue; }

                float clipPercent = (float)(stageTick % clip.duration) / clip.duration;

                ActorBody actorBody = actorBodies[actorID];
                string bodyType = actorBody.bodyType;

                Vector3 deltaPos = new Vector3(clip.BodyOffsetX.Evaluate(clipPercent), 0, clip.BodyOffsetZ.Evaluate(clipPercent));
                deltaPos += Workspace.animationDef.actors[actorID].bodyTypeOffset.GetOffset(bodyType);

                float bodyAngle = clip.BodyAngle.Evaluate(clipPercent);
                float headAngle = clip.HeadAngle.Evaluate(clipPercent);

                if (bodyAngle < 0) bodyAngle = 360 - ((-1f * bodyAngle) % 360);
                if (bodyAngle > 360) bodyAngle %= 360;

                if (headAngle < 0) headAngle = 360 - ((-1f * headAngle) % 360);
                if (headAngle > 360) headAngle %= 360;

                int bodyFacing = (int)clip.BodyFacing.Evaluate(clipPercent);
                int headFacing = (int)clip.HeadFacing.Evaluate(clipPercent);

                Vector3 headBob = new Vector3(0, 0, clip.HeadBob.Evaluate(clipPercent)) + PawnUtility.BaseHeadOffsetAt(bodyType, bodyFacing);

                Vector3 bodyPos = new Vector3(deltaPos.x, deltaPos.z, 0);
                Vector3 headPos = new Vector3(headBob.x, headBob.z, 0);

                actorBody.transform.position = bodyPos;
                actorBody.transform.eulerAngles = new Vector3(0, 0, bodyAngle);

                actorBody.headRenderer.transform.localPosition = headPos;
                actorBody.headRenderer.transform.eulerAngles = new Vector3(0, 0, headAngle);

                actorBody.bodyRenderer.sprite = Resources.Load<Sprite>("Textures/Humanlike/Bodies/" + bodyType + bodyFacing);
                actorBody.headRenderer.sprite = Resources.Load<Sprite>("Textures/Humanlike/Heads/Head" + headFacing);

                actorBody.bodyRenderer.sortingLayerName = clip.layer;
                actorBody.headRenderer.sortingLayerName = clip.layer;
                actorBody.headRenderer.sortingOrder = headFacing == 0 ? -1 : 1;
            }
        }

        public void Initialize()
        {
            Debug.Log("Initializing animation preview");
            Reset();

            InitializeAnimationTimeline();
            StageCardManager.Instance.Initialize();

            Workspace.isDirty = false;
        }

        public void InitializeAnimationTimeline()
        {
            cyclesNormalField.text = Mathf.Max(Mathf.CeilToInt((float)Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicks / Workspace.StageWindowSize), 1).ToString();
            cyclesFastField.text = Mathf.Max(Mathf.CeilToInt((float)Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicksQuick / Workspace.StageWindowSize), 1).ToString();

            for (int actorID = 0; actorID < Workspace.animationDef.actors.Count; actorID++)
            {
                ActorBody actorBody = Instantiate(actorBodyPrefab, transform);
                actorBody.Initialize(actorID);

                AnimationTimeline animationTimeline = Instantiate(animationTimelinePrefab, animationTimelines);
                animationTimeline.Initialize(actorID);
            }

            animationClipLengthField.text = Workspace.StageWindowSize.ToString();
            animationClipTimeField.text = "1";
            stageTimelineSlider.maxValue = Workspace.StageWindowSize;
            stageTimelineSlider.value = 1;
            stageTick = 1;
        }

        public void Reset()
        {
            Workspace.stageID = 0;
            isAnimating = false;
            ResetAnimationTimeline();
            StageCardManager.Instance.Reset();
        }

        public void ResetAnimationTimeline()
        {         
            timeSinceLastUpdate = 0;
            cycleIndex = 0;

            foreach (ActorBody actorBody in GetComponentsInChildren<ActorBody>())
            { Destroy(actorBody.gameObject); }

            foreach (AnimationTimeline animationTimeline in animationTimelines.GetComponentsInChildren<AnimationTimeline>())
            { Destroy(animationTimeline.gameObject); }
        }

        public bool AddAnimationStage()
        {
            AnimationStage stage = new AnimationStage();
 
            return stage.MakeNew();
        }

        public bool CloneAnimationStage()
        {
            AnimationStage stage = Workspace.animationDef.animationStages[Workspace.stageID].Copy();
            stage.Initialize();
            stage.stageName += " (Clone)";

            Workspace.animationDef.animationStages.Insert(Workspace.stageID + 1, stage);

            return true;
        }

        public bool MoveAnimationStage(int startIndex, int delta)
        {
            if (startIndex + delta < 0 || startIndex + delta >= Workspace.animationDef.animationStages.Count)
            { return false; }

            AnimationStage stage = Workspace.animationDef.animationStages[startIndex];
            Workspace.animationDef.animationStages[startIndex] = Workspace.animationDef.animationStages[startIndex + delta];
            Workspace.animationDef.animationStages[startIndex + delta] = stage;

            return true;
        }

        public bool RemoveAnimationStage()
        {
            if (Workspace.animationDef.animationStages.Count == 1)
            { 
                Debug.LogWarning("Cannot delete animation stage - the animation must contain at least one animation stage.");
                return false;
            }

            Workspace.animationDef.animationStages.RemoveAt(Workspace.stageID);
            Workspace.stageID = Workspace.stageID >= Workspace.animationDef.animationStages.Count ? Workspace.stageID = Workspace.animationDef.animationStages.Count - 1 : Workspace.stageID;

            return true;
        }

        public void AddActor()
        {
            Actor actor = new Actor();

            if (actor.MakeNew())
            { Initialize(); }
        }

        public void RemoveActor()
        {
            if (Workspace.animationDef.actors.Count == 1)
            {
                Debug.LogWarning("Cannot delete actor - the animation must contain at least one actor.");
                return;
            }

            foreach (AnimationStage stage in Workspace.animationDef.animationStages)
            { stage.animationClips.RemoveAt(Workspace.actorID); }

            Workspace.animationDef.actors.RemoveAt(Workspace.actorID);
            Workspace.actorID = Workspace.actorID >= Workspace.animationDef.actors.Count ? Workspace.actorID = Workspace.animationDef.actors.Count - 1 : Workspace.actorID;

            Initialize();
        }

        public void AddPawnKeyframe()
        {
            PawnAnimationClip clip = Workspace.Instance.GetCurrentPawnAnimationClip();
            List<PawnKeyframe> keyframes = clip?.keyframes;

            if (clip == null || keyframes == null)
            { Debug.LogWarning("Cannot add pawn keyframe - the AnimationDef is invalid"); return; }

            if (keyframes.FirstOrDefault(x => x.atTick == stageTick) != null)
            { Debug.LogWarning("Cannot add pawn keyframe - a keyframe already exists at this tick"); return; }

            float clipPercent = (float)(stageTick % clip.duration) / clip.duration;

            PawnKeyframe keyframe = new PawnKeyframe();
            keyframe.bodyAngle = clip.BodyAngle.Evaluate(clipPercent);
            keyframe.headAngle = clip.HeadAngle.Evaluate(clipPercent);
            keyframe.headBob = clip.HeadBob.Evaluate(clipPercent);
            keyframe.bodyOffsetX = clip.BodyOffsetX.Evaluate(clipPercent);
            keyframe.bodyOffsetZ = clip.BodyOffsetZ.Evaluate(clipPercent);
            keyframe.headFacing = clip.HeadFacing.Evaluate(clipPercent);
            keyframe.bodyFacing = clip.BodyFacing.Evaluate(clipPercent);
            keyframe.genitalAngle = clip.GenitalAngle.Evaluate(clipPercent);

            keyframe.atTick = stageTick;
            
            PawnKeyframe nextKeyframe = keyframes.FirstOrDefault(x => x.atTick > stageTick);

            if (nextKeyframe != null)
            { keyframes.Insert(keyframes.IndexOf(nextKeyframe), keyframe); }

            else
            { keyframes.Add(keyframe); }

            clip.BuildSimpleCurves();

            animationTimelines.GetComponentsInChildren<AnimationTimeline>()[Workspace.actorID].AddPawnKeyFrame(keyframe.keyframeID);
        }

        public void RemovePawnKeyframe()
        {
            RemovePawnKeyframe(Workspace.actorID, Workspace.keyframeID);
        }

        public void RemovePawnKeyframe(int actorID, int keyframeID)
        {
            PawnKeyframe keyframe = Workspace.Instance.GetPawnKeyframe(actorID, keyframeID);

            if (keyframe != null && keyframe.atTick == 1)
            { Debug.LogWarning("Cannot delete key frame - the first key frame of an animation cannot be deleted"); return; }

            if (keyframe != null)
            {
                animationTimelines.GetComponentsInChildren<AnimationTimeline>()[Workspace.actorID].RemovePawnKeyFrame(keyframe.keyframeID);

                PawnAnimationClip clip = Workspace.animationDef.animationStages[Workspace.stageID].animationClips[actorID];
                clip.keyframes.Remove(keyframe);
                clip.BuildSimpleCurves();
            }
        }

        public void ToggleAnimation()
        {
            isAnimating = !isAnimating;
        }

        public void ToggleActorManipulationMode(int mode)
        {
            Workspace.actorManipulationMode = (ActorManipulationMode)mode;
        }

        public void OnStageTimelineSliderChange()
        {
            if (Workspace.animationDef == null) return;

            if (stageTick != (int)stageTimelineSlider.value)
            { 
                stageTick = (int)stageTimelineSlider.value;
                animationClipTimeField.text = stageTick.ToString();
            }
        }

        public void OnAnimationClipTimeFieldChange()
        {
            if (Workspace.animationDef == null) return;

            int.TryParse(animationClipTimeField.text, out int newStageTick);
            stageTick = Mathf.Clamp(newStageTick, 1, Workspace.StageWindowSize);
            stageTimelineSlider.value = stageTick;
        }

        public void OnAnimationClipLengthFieldChange()
        {
            if (Workspace.animationDef == null) return;

            int.TryParse(animationClipLengthField.text, out int newstageWindowSize);
            newstageWindowSize = Mathf.Clamp(newstageWindowSize, Constants.minAnimationClipLength, Constants.maxAnimationClipLength);

            Debug.Log("Resizing animation clip length to " + newstageWindowSize.ToString() + " ticks.");

            for (int i = 0; i < Workspace.animationDef.animationStages[Workspace.stageID].animationClips.Count; i++)
            {
                PawnAnimationClip clip = Workspace.animationDef.animationStages[Workspace.stageID].animationClips[i];
                List<PawnKeyframe> keyframes = clip.keyframes.Where(x => x.atTick > newstageWindowSize)?.ToList();

                if (keyframes.NullOrEmpty())
                { continue; }

                foreach (PawnKeyframe keyframe in keyframes)
                { 
                    RemovePawnKeyframe(i, keyframe.keyframeID);

                    if (Workspace.animationDef.animationStages[Workspace.stageID].animationClips[i].keyframes.Count <= 2)
                    { break; }
                }
            }

            animationClipLengthField.text = newstageWindowSize.ToString();
            Workspace.animationDef.animationStages[Workspace.stageID].stageWindowSize = newstageWindowSize;

            //ResetAnimationTimeline();
            //InitializeAnimationTimeline();
        }

        public void OnCycleNormalFieldChange()
        {
            if (Workspace.animationDef == null) return;

            if (int.TryParse(cyclesNormalField.text, out int cycles))
            { Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicks = cycles * Workspace.StageWindowSize; }
        }

        public void OnCycleFastFieldChange()
        {
            if (Workspace.animationDef == null) return;

            if (int.TryParse(cyclesFastField.text, out int cycles))
            { Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicksQuick = cycles * Workspace.StageWindowSize; }
        }
    }
}