using System;
using System.Collections;
using System.Collections.Generic;
using PixelCrushers;
using UnityEngine;
using UnityEngine.Events;

namespace Beyond
{
    public class KillTrigger : Saver
    {
        [SerializeField] EnemySpawner[] m_spawners;

        public UnityEvent<KillTrigger> OnTrigger;

        [Serializable]
        public class SaveData
        {
            public bool wasTriggered = false;
        }

        private SaveData m_data = new SaveData();
        void Start()
        {
            if (m_spawners == null) return; // Guard clause
            foreach (var s in m_spawners)
            {
                if (s != null) // Good practice to check for null spawners in array
                {
                    s.m_OnDead.AddListener(OnEnemyKilled);
                }
            }
        }

        public void CheckSpawners()
        {
            if (m_data.wasTriggered)
                return;

            if (m_spawners == null) return; // Guard clause

            foreach (var spawner in m_spawners)
            {
                if (spawner == null) continue; // Skip if a spawner in the array is null

                 bool hasSpawnedAWave = spawner.GetWavesSpawnedCount() > 0; // We'll need to add this getter to EnemySpawner
                bool noEnemiesCurrentlyAlive = !spawner.IsAnyEnemyAlive();

                if (hasSpawnedAWave && noEnemiesCurrentlyAlive)
                {
                    // This spawner has done its part for *this current engagement*
                }
                else
                {
                    return; // If ANY spawner doesn't meet this, the trigger condition isn't met
                }
            }
            OnTrigger?.Invoke(this);
            m_data.wasTriggered = true;
        }
        private void OnEnemyKilled(EnemySpawner arg0)
        {
            // arg0 is the spawner from which an enemy died.
            // We need to check all spawners associated with this trigger.
            CheckSpawners();
        }

        private void OnDestroy()
        {
            if (m_spawners == null) return; // Guard clause
            foreach (var s in m_spawners)
            {
                if (s != null) // Good practice
                {
                    s.m_OnDead.RemoveListener(OnEnemyKilled);
                }
            }
        }

        public override string RecordData()
        {
            return SaveSystem.Serialize(m_data);
        }

        public override void ApplyData(string s)
        {
            var data = SaveSystem.Deserialize<SaveData>(s);
            if (data != null)
                m_data = data;
            // Optional: if not triggered, re-check on load in case state was met while inactive
            // if (!m_data.wasTriggered) { CheckSpawners(); }
        }
    }
}