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

namespace Ichni.Editor.Commands
{
    public class ChangeValueCommand : ICommand
    {
        private IBaseElement target;
        private string path;
        private object oldValue;
        private object newValue;
        private float timestamp;
        
        // 合并窗口期：同一字段 1 秒内的接连覆盖，只算作一次编辑行为
        private const float MERGE_WINDOW = 1f;

        public ChangeValueCommand(IBaseElement target, string path, object newValue)
        {
            this.target = target;
            this.path = path;
            this.newValue = newValue;
            this.oldValue = ReflectionHelper.GetDeepValue(target, path);
            this.timestamp = Time.realtimeSinceStartup;
        }

        public void Execute()
        {
            if (target == null) return;
            ReflectionHelper.SetDeepValue(target, path, newValue);
        }

        public void Undo()
        {
            // 防暴毙机制：如果所附着的对象因为其它原因在场景中已被销毁（如删除该 Note），自动拦截撤销并停止访问底层数据。
            if (target == null) return; 

            ReflectionHelper.SetDeepValue(target, path, oldValue);
            target.Refresh(); 
            
            
        }

        public void Redo()
        {
            if (target == null) return;

            ReflectionHelper.SetDeepValue(target, path, newValue);
            target.Refresh();
            
            
        }

        public bool TryMerge(ICommand other)
        {
            if (other is ChangeValueCommand otherCommand)
            {
                // 若对象、路径完全一致，则尝试吞并它的新值
                if (System.Object.ReferenceEquals(this.target, otherCommand.target) && 
                    this.path == otherCommand.path && 
                   (otherCommand.timestamp - this.timestamp) < MERGE_WINDOW)
                {
                    this.newValue = otherCommand.newValue;
                    this.timestamp = otherCommand.timestamp;
                    return true;
                }
            }
            return false;
        }

        private void RefreshInspectorIfMatched()
        {
            var inspector = EditorManager.instance.uiManager.inspector;
            if (inspector != null && inspector.connectedGameElement != null)
            {
                // 由于目前 DynamicUI 未实现细粒度的数据绑定事件派发，发生撤回时，我们重新装载选择一次右侧属性窗面板以完成显示同步。
                // 借由我们之前的对象池机制，这个 SetInspector 消耗会在低于 1ms 的时间内无感重构。
                inspector.SetInspector(inspector.connectedGameElement);
            }
        }
    }
}