using UnityEngine;
using System;

namespace Architecture.Variables
{
    /// <summary>
    /// 共享浮点变量（ScriptableObject 资产）。
    /// 任何系统可读取 / 写入，并由 OnValueChanged 事件驱动 UI 刷新，
    /// 替代 MonoBehaviour 字段跨系统传递与逐帧反射读取。
    /// </summary>
    [CreateAssetMenu(menuName = "Architecture/Variables/Float", fileName = "NewFloatVariable")]
    public class FloatVariable : ScriptableObject, Architecture.IVariable
    {
        [SerializeField] private float _value;

        [Tooltip("进入 Play Mode 时的初始值，由 VariableRegistry 在每次启动游戏时自动恢复，防止跨局状态泄漏")]
        [SerializeField] private float _defaultValue;

        public float Value
        {
            get => _value;
            set
            {
                if (Mathf.Approximately(_value, value)) return;
                _value = value;
                OnValueChanged?.Invoke(value);
            }
        }

        public event Action<float> OnValueChanged;

        public void SetValue(float value) => Value = value;
        public void ApplyChange(float amount) => Value += amount;

        /// <summary>将运行时值重置为 _defaultValue（每次进入 Play Mode 时由 VariableRegistry 自动调用）。</summary>
        public void ResetToDefault()
        {
            _value = _defaultValue;
            OnValueChanged?.Invoke(_value);
        }

        [ContextMenu("Reset To Default")]
        public void Reset() => ResetToDefault();

        private void OnEnable() => VariableRegistry.Register(this);
        private void OnDisable()
        {
            VariableRegistry.Unregister(this);
            OnValueChanged = null;
        }
    }
}