enemy spawner

Game/Scripts/Runtime/Data/SpawnTable.cs

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+using System;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace Game.Scripts.Runtime.Data
+{
+    [CreateAssetMenu(menuName = "Game/Spawning/Spawn Table", fileName = "SpawnTable")]
+    public class SpawnTable : ScriptableObject
+    {
+        [Serializable]
+        public class Entry
+        {
+            public EnemyDefinition Def;
+            [Min(0)] public int Weight = 1;
+            public int MinWave = 0;
+            public int MaxWave = int.MaxValue;
+            [Tooltip("Optional cap per wave. Values <= 0 mean unlimited.")]
+            public int Cap = -1;
+
+            public bool IsWaveValid(int wave) => wave >= MinWave && wave <= MaxWave;
+
+            public bool IsUnderCap(int currentCount)
+            {
+                if (Cap <= 0)
+                {
+                    return true;
+                }
+
+                return currentCount < Cap;
+            }
+        }
+
+        [SerializeField] private List<Entry> entries = new();
+
+        private readonly List<Entry> _eligibleBuffer = new();
+
+        public IReadOnlyList<Entry> Entries => entries;
+
+        public EnemyDefinition Pick(int wave, System.Random rng)
+        {
+            if (entries == null || entries.Count == 0)
+            {
+                return null;
+            }
+
+            _eligibleBuffer.Clear();
+            foreach (var entry in entries)
+            {
+                if (entry?.Def == null || entry.Weight <= 0)
+                {
+                    continue;
+                }
+
+                if (entry.IsWaveValid(wave))
+                {
+                    _eligibleBuffer.Add(entry);
+                }
+            }
+
+            if (_eligibleBuffer.Count == 0)
+            {
+                return null;
+            }
+
+            var totalWeight = 0;
+            foreach (var entry in _eligibleBuffer)
+            {
+                totalWeight += Mathf.Max(1, entry.Weight);
+            }
+
+            var roll = rng.Next(totalWeight);
+            foreach (var entry in _eligibleBuffer)
+            {
+                var weight = Mathf.Max(1, entry.Weight);
+                if (roll < weight)
+                {
+                    return entry.Def;
+                }
+
+                roll -= weight;
+            }
+
+            return _eligibleBuffer[^1].Def;
+        }
+
+        public IEnumerable<Entry> EnumerateEligibleEntries(int wave)
+        {
+            if (entries == null)
+            {
+                yield break;
+            }
+
+            foreach (var entry in entries)
+            {
+                if (entry?.Def == null || entry.Weight <= 0)
+                {
+                    continue;
+                }
+
+                if (entry.IsWaveValid(wave))
+                {
+                    yield return entry;
+                }
+            }
+        }
+    }
+}