trail-into-darkness/Packages/com.jovian.encounter-system/Runtime/EncounterTable.cs

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

namespace Jovian.EncounterSystem {
    [CreateAssetMenu(fileName = "EncounterTable", menuName = "Jovian/Encounter System/Encounter Table", order = 1)]
    public class EncounterTable : ScriptableObject {
        public string id;
        public List<Encounter> encounters;

        public IEncounter GetRandomEncounter() {
            if(encounters == null || encounters.Count == 0) {
                return null;
            }

            return encounters[UnityEngine.Random.Range(0, encounters.Count)];
        }

        public IEncounter GetRandomEncounter(Type type) {
            if(encounters == null || encounters.Count == 0) {
                return null;
            }

            var encountersOfType = encounters.FindAll(encounter => encounter.GetType() == type);
            if(encountersOfType.Count > 0) {
                return encountersOfType[UnityEngine.Random.Range(0, encountersOfType.Count)];
            }

            return null;
        }

        /// <summary>Random pick limited by a predicate. Used with <see cref="QuestProgress.IsGated"/> to exclude gated encounters.</summary>
        public IEncounter GetRandomEncounter(Predicate<IEncounter> filter) {
            if(encounters == null || encounters.Count == 0 || filter == null) {
                return GetRandomEncounter();
            }

            var pool = encounters.FindAll(filter);
            if(pool.Count == 0) {
                return null;
            }

            return pool[UnityEngine.Random.Range(0, pool.Count)];
        }
    }
}