using System;
using System.Collections;
using System.Collections.Generic;
using Ichni.RhythmGame.Beatmap;
using UnityEngine;

namespace Ichni.RhythmGame
{
    public partial class Scale : AnimationBase
    {
        #region [暴露属性字段与关联] Exposed Fields & References
        public TransformSubmodule targetTransformSubmodule;
        public FlexibleFloat scaleX, scaleY, scaleZ;
        
        // 静态跟踪全局激活的Scale组件，为了方便同物体的跨动画状态感应
        public static HashSet<Scale> ActiveScales = new HashSet<Scale>();
        #endregion

        protected void OnEnable() { ActiveScales.Add(this); }
        protected void OnDisable() { ActiveScales.Remove(this); }

        #region [生命周期与工厂] Lifecycle & Factory
        public static Scale GenerateElement(string elementName, Guid id,
            List<string> tags, bool isFirstGenerated, GameElement animatedObject,
            FlexibleFloat scaleX, FlexibleFloat scaleY, FlexibleFloat scaleZ)
        {
            Scale scale = Instantiate(GameManager.Instance.basePrefabs.emptyObject).AddComponent<Scale>();

            scale.Initialize(elementName, id, tags, isFirstGenerated, animatedObject);

            scale.animatedObject = animatedObject;

            scale.scaleX = scaleX;
            scale.scaleY = scaleY;
            scale.scaleZ = scaleZ;
            scale.animationReturnType = FlexibleReturnType.Before;

            scale.targetTransformSubmodule = (animatedObject as IHaveTransformSubmodule).transformSubmodule;
            //scale.timeDurationSubmodule.SetDuration(scaleX, scaleY, scaleZ);

            return scale;
        }

        public override void SetDefaultSubmodules()
        {
            timeDurationSubmodule = new TimeDurationSubmodule(this);
        }
        #endregion

        #region [核心动画逻辑] Core Animation Logic

        protected override void UpdateAnimation(float songTime, bool forceUpdate)
        {
            scaleX.UpdateFlexibleFloat(songTime);
            scaleY.UpdateFlexibleFloat(songTime);
            scaleZ.UpdateFlexibleFloat(songTime);

            bool isMiddleExecuting = scaleX.returnType is FlexibleReturnType.MiddleExecuting ||
                                     scaleY.returnType is FlexibleReturnType.MiddleExecuting ||
                                     scaleZ.returnType is FlexibleReturnType.MiddleExecuting;

            bool isSwitching = scaleX.isSwitchingReturnType || scaleY.isSwitchingReturnType || scaleZ.isSwitchingReturnType;

            if (forceUpdate || isMiddleExecuting)
            {
                if(!forceUpdate) animationReturnType = FlexibleReturnType.MiddleExecuting;
                
                // 检查是否是刚开始的第一帧，且有其它同类动画正在收尾（避免两帧叠加导致 ScaleX2）
                bool shouldSkipFirstFrame = false;
                if (!forceUpdate && isSwitching)
                {
                    foreach (var s in ActiveScales)
                    {
                        if (s != this && s.targetTransformSubmodule == this.targetTransformSubmodule)
                        {
                            if (s.scaleX.isSwitchingReturnType || s.scaleY.isSwitchingReturnType || s.scaleZ.isSwitchingReturnType)
                            {
                                shouldSkipFirstFrame = true;
                                break;
                            }
                        }
                    }
                }

                if (!shouldSkipFirstFrame)
                {
                    Vector3 currentScale = new Vector3(scaleX.value, scaleY.value, scaleZ.value);
                    targetTransformSubmodule.scaleOffset += currentScale;
                    targetTransformSubmodule.scaleDirtyMark = true;
                }
            }
            else if (isSwitching)
            {
                // 【收尾保护】如果这个动画是附着物体的“最后的动画”的结束，额外更新彻底将其设为终定值
                bool isAnyOtherExecuting = false;
                foreach (var s in ActiveScales)
                {
                    if (s != this && s.targetTransformSubmodule == this.targetTransformSubmodule)
                    {
                        if (s.scaleX.returnType is FlexibleReturnType.MiddleExecuting ||
                            s.scaleY.returnType is FlexibleReturnType.MiddleExecuting ||
                            s.scaleZ.returnType is FlexibleReturnType.MiddleExecuting)
                        {
                            isAnyOtherExecuting = true;
                            break;
                        }
                    }
                }

                if (!isAnyOtherExecuting)
                {
                    animationReturnType = FlexibleReturnType.MiddleExecuting; // 使系统认为有有效活动
                    Vector3 currentScale = new Vector3(scaleX.value, scaleY.value, scaleZ.value);
                    targetTransformSubmodule.scaleOffset += currentScale;
                    targetTransformSubmodule.scaleDirtyMark = true;
                }
            }
            else
            {
                animationReturnType = FlexibleReturnType.MiddleInterval;
            }
        }

        public override void ApplyTimeOffset(float offset)
        {
            base.ApplyTimeOffset(offset);
            scaleX.animations.ForEach(anim => anim.ApplyTimeOffset(offset));
            scaleY.animations.ForEach(anim => anim.ApplyTimeOffset(offset));
            scaleZ.animations.ForEach(anim => anim.ApplyTimeOffset(offset));
        }
        #endregion
    }

}