Stat

using System;
using Game.Tools.Extensions;
using UnityEngine;

namespace Game.Stats
{
    public sealed class Stat : IStat
    {
        private readonly int _max;
        private readonly IStatChanged _changed;

        private int _value;

        public Stat(int max, IStatChanged changed)
        {
            _max = max.ThrowExceptionIfLessThanOrEqualToZero(nameof(max));
            _value = max;
            _changed = changed ?? throw new ArgumentNullException(nameof(changed));
        }

        public void Add(int value = 1) =>
            ChangeValue(value);

        public void Subtract(int value = 1) =>
            ChangeValue(-value);

        private void ChangeValue(int value)
        {
            _value += value;
            _value = Mathf.Clamp(_value, 0, _max);

            _changed.OnStatChanged(_value, _max);
        }
    }
}