using System.Collections;
using UnityEngine;
using UnityEngine.Events;

public class Level1 : Level
{
    [Header("Wave Flow")]
    public WaveSpawner spawner;                 // Assign in Inspector
    [Min(0.05f)] public float checkInterval = 0.25f;

    private bool _running;
    private Coroutine _monitorCo;

    // Optional: simple counters for UI hooks
    private int _currentWaveIdx = -1;
    private int _totalWaves = 0;
    private int _currentAlive = 0;
    private void OnEnable()
    {
        if (spawner != null)
        {
            spawner.OnWaveStarted += HandleWaveStarted;
            spawner.OnWaveCompleted += HandleWaveCompleted;
            spawner.OnAllWavesCompleted += HandleAllWavesCompleted;
            spawner.OnAliveCountChanged += HandleAliveChanged;
        }
    }

    private void OnDisable()
    {
        if (spawner != null)
        {
            spawner.OnWaveStarted -= HandleWaveStarted;
            spawner.OnWaveCompleted -= HandleWaveCompleted;
            spawner.OnAllWavesCompleted -= HandleAllWavesCompleted;
            spawner.OnAliveCountChanged -= HandleAliveChanged;
        }
    }

    public override void OnLevelStart()
    {
        base.OnLevelStart();

        if (spawner == null)
        {
            Debug.LogError("[Level1] No WaveSpawner assigned.");
            CompleteLevelImmediate();
            return;
        }

        _totalWaves = spawner.TotalWaves;
        _running = true;

        // Kick off waves
        spawner.StartSpawning();

        // As an extra safeguard, monitor completion state
        _monitorCo = StartCoroutine(MonitorForCompletion());
        Debug.Log("[Level1] Level started, waves spawning…");
    }

    public override void OnLevelEnd()
    {   
        base.OnLevelEnd();
        _running = false;

        if (_monitorCo != null)
        {
            StopCoroutine(_monitorCo);
            _monitorCo = null;
        }
        Debug.Log("OnLevelEndCalled");
    }

    private IEnumerator MonitorForCompletion()
    {
        var wait = new WaitForSeconds(checkInterval);
        while (_running)
        {
            // Complete when spawner reports all waves completed AND no alive remain
            if (spawner.AllWavesCompleted && spawner.CurrentAlive == 0)
            {
                CompleteLevelImmediate();
                yield break;
            }
            yield return wait;
        }
    }

    private void CompleteLevelImmediate()
    {
        _running = false;
        Debug.Log("[Level1] All waves cleared. Level complete!");

        if (GameplayManager.Instance != null)
            GameplayManager.Instance.CompleteCurrentLevel();
        else
            gameObject.SetActive(false);
    }

    // ===== Event handlers (useful for UI/logs/hook-ins) =====
    private void HandleWaveStarted(int waveIdx, WaveSpawner.Wave wave)
    {
        _currentWaveIdx = waveIdx;
        Debug.Log($"[Level1] Wave {waveIdx + 1}/{_totalWaves} started. Count={wave.count}, Rate={wave.spawnRate:F2}/s");
        // TODO: Update UI: “Wave X/Y starting”
    }

    private void HandleWaveCompleted(int waveIdx)
    {
        Debug.Log($"[Level1] Wave {waveIdx + 1}/{_totalWaves} completed.");
        // TODO: UI “Wave complete”
    }

    private void HandleAllWavesCompleted()
    {
        Debug.Log("[Level1] All waves spawned. Waiting for last enemies to die…");
        // Completion is finalized in MonitorForCompletion once alive == 0
    }

    private void HandleAliveChanged(int currentAlive)
    {
        _currentAlive = currentAlive;
        // TODO: UI “Enemies Left: currentAlive”
    }
}