idle-survivors/Assets/Scripts/Wave/SpawnPackSO.cs

using System.Collections.Generic;
using System.Collections.ObjectModel;
using DefaultNamespace;
using UnityEngine;
using UnityEngine.Assertions;

namespace Wave
{
    [CreateAssetMenu(fileName = "SpawnPack", menuName = "Spawn/Pack", order = 0)]
    public class SpawnPackSO : ScriptableObject
    {
        [SerializeField] private List<Enemy> possibleEnemies;
        [SerializeField] [Min(0)] private int minCount;
        [SerializeField] [Min(0)] private int maxCount;
        
        public ReadOnlyCollection<Enemy> EnemiesToSpawn()
        {
            Assert.IsTrue(possibleEnemies.Count > 0);
            
            var count = Random.Range(minCount, maxCount);
            var enemiesToSpawn = new List<Enemy>();
            
            for (var i = 0; i < count; i++)
            {
                var enemyIndex = Random.Range(0, possibleEnemies.Count);
                enemiesToSpawn.Add(possibleEnemies[enemyIndex]);
            }

            return enemiesToSpawn.AsReadOnly();
        }
    }
}