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;
        public Transform actorBodies;
        public Toggle stretchkeyframesToggle;
        public InputField playBackSpeedField;
        public Button playToggleButton;

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

        // Private timing variables
        private int lastStageTick = 1;
        private float timeSinceLastUpdate = 0;
        private int cycleIndex = 0;
        private bool isDirty = true;
        private bool isTimelineDirty = true;
        private float playBackSpeed = 1f;

        public void MakeDirty()
        { isDirty = true; }

        public void MakeTimelineDirty()
        { isTimelineDirty = true; }

        public void Update()
        {
            // No animation, exit
            if (Workspace.animationDef == null) { return; }

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

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

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

                timeSinceLastUpdate -= 1 / (playBackSpeed * 60f);
                stageTick += 1;

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

                    else if (stageLoopDropdown.value >= 2)
                    {
                        ++cycleIndex;
                        stageTick = 1;

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

                        if (Workspace.stageID > Workspace.animationDef.animationStages.Count - 1)
                        {
                            Workspace.stageID = Workspace.animationDef.animationStages.Count - 1;
                            stageTick = Workspace.StageWindowSize;
                            isAnimating = false;
                        }
                    }

                    else
                    { 
                        stageTick = Workspace.StageWindowSize; 
                        isAnimating = false; 
                    }
                }
            }

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

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

            playToggleButton.image.color = isAnimating ? Constants.ColorGoldYellow : Constants.ColorWhite;

            // Update animation
            UpdateAnimation();
        }

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

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

            for (int actorID = 0; actorID < _actorBodies.Count; actorID++)
            {
                if (Workspace.stageID >= Workspace.animationDef?.animationStages.Count)
                { Debug.Log("Waiting for animation stage data to initialize..."); return; }

                if (actorID >= Workspace.animationDef?.animationStages[Workspace.stageID]?.animationClips.Count)
                { Debug.Log("Waiting for animation clip data to initialize..."); return; }

                Actor actor = Workspace.animationDef.actors[actorID];
                PawnAnimationClip clip = Workspace.animationDef?.animationStages[Workspace.stageID]?.animationClips[actorID];
                
                if (clip == null)
                { continue; }

                float clipPercent = (float)(stageTick % clip.duration) / clip.duration;
                if (stageTick == clip.duration) clipPercent = 1f;

                AlienRaceDef alienRaceDef = actor.GetAlienRaceDef();
                ActorBody actorBody = _actorBodies[actorID];
                string bodyType = alienRaceDef.isHumanoid ? actor.bodyType : "None";

                Vector3 deltaPos = new Vector3(clip.BodyOffsetX.Evaluate(clipPercent), 0, clip.BodyOffsetZ.Evaluate(clipPercent));
                deltaPos += actor.bodyTypeOffset.GetOffset(bodyType) + actor.GetAlienRaceOffset();

                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;

                bodyAngle = bodyAngle > 180 ? 180 - bodyAngle : bodyAngle;
                headAngle = headAngle > 180 ? 180 - headAngle : headAngle;*/

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

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

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

                Vector3 appendagePos = PawnUtility.AppendageOffsetAt(bodyType, bodyFacing);
                float appendageRotation = clip.GenitalAngle.Evaluate(clipPercent);

                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.appendageRenderer.transform.localPosition = new Vector3(appendagePos.x, appendagePos.z, 0f);
                actorBody.appendageRenderer.transform.eulerAngles = new Vector3(0, 0, -appendageRotation);

                actorBody.bodyRenderer.sprite = alienRaceDef.GetBodyTypeGraphic((CardinalDirection)bodyFacing, bodyType);
                actorBody.headRenderer.sprite = alienRaceDef.isHumanoid ? alienRaceDef.GetHeadGraphic((CardinalDirection)headFacing) : null;
                actorBody.appendageRenderer.sprite = alienRaceDef.isHumanoid && bodyFacing != 0 ? Resources.Load<Sprite>("Textures/Humanlike/Appendages/Appendage" + bodyFacing) : null;

                actorBody.bodyRenderer.gameObject.SetActive(actorBody.bodyRenderer.sprite != null);
                actorBody.headRenderer.gameObject.SetActive(actorBody.headRenderer.sprite != null);
                actorBody.appendageRenderer.gameObject.SetActive(actorBody.appendageRenderer.sprite != null);

                actorBody.bodyRenderer.sortingLayerName = clip.layer;
                actorBody.headRenderer.sortingLayerName = clip.layer;
                actorBody.headRenderer.sortingOrder = bodyFacing == 0 ? -1 : 1;
                actorBody.appendageRenderer.sortingLayerName = clip.layer;

                actorBody.bodyRenderer.flipX = bodyFacing == 3;
                actorBody.headRenderer.flipX = headFacing == 3;
                //actorBody.appendageRenderer.flipX = bodyFacing == 3;

                actorBody.transform.localScale = new Vector3(alienRaceDef.scale, alienRaceDef.scale, alienRaceDef.scale);

                // ActorKeyframeCard update
                if (actorID != Workspace.actorID) continue;
                if (ActorKeyframeCard.Instance.positionXField.isFocused == false) { ActorKeyframeCard.Instance.positionXField.text = bodyPos.x.ToString("0.000"); }
                if (ActorKeyframeCard.Instance.positionZField.isFocused == false) { ActorKeyframeCard.Instance.positionZField.text = bodyPos.y.ToString("0.000"); }
                if (ActorKeyframeCard.Instance.rotationField.isFocused == false) { ActorKeyframeCard.Instance.rotationField.text = bodyAngle.ToString("0.000"); }
                if (ActorKeyframeCard.Instance.headBobField.isFocused == false) { ActorKeyframeCard.Instance.headBobField.text = headBob.ToString("0.000"); }
                if (ActorKeyframeCard.Instance.headRotationField.isFocused == false) { ActorKeyframeCard.Instance.headRotationField.text = headAngle.ToString("0.000"); }
                if (ActorKeyframeCard.Instance.appendageRotationField.isFocused == false) { ActorKeyframeCard.Instance.appendageRotationField.text = appendageRotation.ToString("0.000"); }
            }
        }

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

            foreach (Transform child in transform)
            { child.gameObject.SetActive(true); }

            Reset();

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

            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, actorBodies.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;

            isTimelineDirty = false;
        }

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

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

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

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

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

            Workspace.Instance.RecordEvent("Actor addition");
        }

        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;

            Workspace.Instance.RecordEvent("Actor deletion");
        }

        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);

            Workspace.Instance.RecordEvent("Keyframe addition");
        }

        public void ClonePawnKeyframe()
        {
            PawnAnimationClip clip = Workspace.Instance.GetCurrentPawnAnimationClip();
            List<PawnKeyframe> keyframes = clip?.keyframes;
            PawnKeyframe keyframe = Workspace.Instance.GetPawnKeyframe(Workspace.actorID, Workspace.keyframeID);

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

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

            if (keyframe == null)
            { Debug.LogWarning("Cannot clone pawn keyframe - no keyframe has been selected for cloning"); return; }

            PawnKeyframe cloneFrame = keyframe.Copy();
            cloneFrame.GenerateKeyframeID();
            cloneFrame.atTick = stageTick;

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

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

            else
            { keyframes.Add(cloneFrame); }

            clip.BuildSimpleCurves();

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

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

        public void RemovePawnKeyframe(int actorID, int keyframeID)
        {
            PawnKeyframe keyframe = Workspace.Instance.GetPawnKeyframe(actorID, keyframeID);
            PawnAnimationClip clip = Workspace.animationDef.animationStages[Workspace.stageID].animationClips[actorID];

            if (keyframe == null || clip == null) return;

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

            if (clip.keyframes.Count <= 2)
            { Debug.LogWarning("Cannot delete key frame - an animation clip must have two or more keyframes"); return; }

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

            clip.keyframes.Remove(keyframe);
            clip.BuildSimpleCurves();

            Workspace.Instance.RecordEvent("Keyframe deletion");          
        }

        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.");

            if (stretchkeyframesToggle.isOn)
            { StretchKeyframes(newStageWindowSize); }

            else
            {
                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;

            Workspace.Instance.RecordEvent("Stage length");
        }

        public void StretchKeyframes(int newStageWindowSize)
        {
            float scale = (float)newStageWindowSize / Workspace.StageWindowSize;

            foreach (PawnAnimationClip clip in Workspace.animationDef.animationStages[Workspace.stageID].animationClips)
            {
                foreach (PawnKeyframe keyframe in clip.keyframes)
                {
                    keyframe.tickDuration = Mathf.RoundToInt(keyframe.tickDuration * scale);
                    keyframe.atTick = null;
                }

                clip.BuildSimpleCurves();
            }
        }

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

            if (int.TryParse(cyclesNormalField.text, out int cycles))
            {
                cycles = cycles <= 0 ? 1 : cycles;

                Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicks = cycles * Workspace.StageWindowSize; 
                Workspace.animationDef.animationStages[Workspace.stageID].isLooping = cycles > 1;

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

            Workspace.Instance.RecordEvent("Cycle count (normal)");
        }

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

            if (int.TryParse(cyclesFastField.text, out int fastCycles))
            {
                fastCycles = fastCycles < 0 ? 0 : fastCycles;

                int.TryParse(cyclesNormalField.text, out int cycles);
                if (fastCycles > cycles) fastCycles = cycles;
                cyclesFastField.text = fastCycles.ToString();

                Workspace.animationDef.animationStages[Workspace.stageID].playTimeTicksQuick = fastCycles * Workspace.StageWindowSize;
            }

            Workspace.Instance.RecordEvent("Cycle count (fast)");
        }

        public void OnPlayBackSpeedChange()
        {
            if (float.TryParse(playBackSpeedField.text, out playBackSpeed))
            { playBackSpeed = Mathf.Clamp(playBackSpeed, 0.01f, 16f); }

            playBackSpeedField.text = playBackSpeed.ToString();
        }

        private int lastactorCount = 0;
        private int lastStageID = 0;
        private int lastStageCount = 0;
        private int lastStageWindowSize = 0;

        public bool AnimationTimelinesNeedUpdate()
        {
            if (Workspace.animationDef == null) return false;

            bool update = isTimelineDirty;

            if (lastStageID != Workspace.stageID)
            { update = true; }

            if (lastStageCount != Workspace.animationDef.animationStages.Count)
            { update = true; }

            if (lastactorCount != Workspace.animationDef.actors.Count)
            { update = true; }

            if (lastStageWindowSize != Workspace.StageWindowSize)
            { update = true; }

            if (update)
            {
                lastStageID = Workspace.stageID;
                lastStageCount = Workspace.animationDef.animationStages.Count;
                lastactorCount = Workspace.animationDef.actors.Count;
                lastStageWindowSize = Workspace.StageWindowSize;

                return true;
            }

            return false;
        }
    }
}