gather-and-defend/Assets/Scripts/ResourceMaker.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ResourceMaker : MonoBehaviour
{
    [SerializeField] 
    private int _resourceMakingAmount;
    [SerializeField] 
    private ResourceChoice _resourceChoice;

    private ResourceManager _resourceManager;
    private enum ResourceChoice
    {
        Rock,
        Wood,
        Food
    };

    private void Start()
    {
        _resourceManager = ResourceManager.Instance;
    }

    public void GenerateResource()
    {
        switch (_resourceChoice)
        {
            case ResourceChoice.Rock:
                _resourceManager.RockGenerationAmount(_resourceMakingAmount,ResourceManager.AddOrRemove.Add);
                break;
            case ResourceChoice.Wood:
                _resourceManager.WoodGenerationAmount(_resourceMakingAmount, ResourceManager.AddOrRemove.Add);
                break;
            case ResourceChoice.Food:
                _resourceManager.FoodGenerationAmount(_resourceMakingAmount, ResourceManager.AddOrRemove.Add);
                break;
        }
    }

    private void OnDestroy()
    {
        switch (_resourceChoice)
        {
            case ResourceChoice.Rock:
                _resourceManager.RockGenerationAmount(_resourceMakingAmount, ResourceManager.AddOrRemove.Remove);
                break;
            case ResourceChoice.Wood:
                _resourceManager.WoodGenerationAmount(_resourceMakingAmount, ResourceManager.AddOrRemove.Remove);
                break;
            case ResourceChoice.Food:
                _resourceManager.FoodGenerationAmount(_resourceMakingAmount, ResourceManager.AddOrRemove.Remove);
                break;
        }
    }
}