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

namespace Minigames.DivingForPictures
{
    /// <summary>
    /// Spawns and manages mobile obstacles for the diving minigame.
    /// Uses object pooling and validates spawn positions to avoid colliding with tiles.
    /// </summary>
    public class ObstacleSpawner : MonoBehaviour
    {
        [Header("Obstacle Prefabs")]
        [Tooltip("List of possible obstacle prefabs to spawn")]
        [SerializeField] private List<GameObject> obstaclePrefabs;

        [Header("Spawn Settings")]
        [Tooltip("Time interval between spawn attempts (in seconds)")]
        [SerializeField] private float spawnInterval = 2f;
        
        [Tooltip("Random variation in spawn timing (+/- seconds)")]
        [SerializeField] private float spawnIntervalVariation = 0.5f;
        
        [Tooltip("Maximum number of spawn position attempts before skipping")]
        [SerializeField] private int maxSpawnAttempts = 10;
        
        [Tooltip("Radius around spawn point to check for tile collisions")]
        [SerializeField] private float spawnCollisionRadius = 1f;

        [Header("Spawn Position")]
        [Tooltip("How far below screen to spawn obstacles")]
        [SerializeField] private float spawnDistanceBelowScreen = 2f;

        [Tooltip("Horizontal spawn range (distance from center)")]
        [SerializeField] private float spawnRangeX = 8f;

        [Header("Obstacle Properties Randomization")]
        [Tooltip("Minimum movement speed for spawned obstacles")]
        [SerializeField] private float minMoveSpeed = 1f;
        
        [Tooltip("Maximum movement speed for spawned obstacles")]
        [SerializeField] private float maxMoveSpeed = 4f;

        [Header("Object Pooling")]
        [Tooltip("Whether to use object pooling for obstacles")]
        [SerializeField] private bool useObjectPooling = true;
        
        [Tooltip("Maximum objects per prefab type in pool")]
        [SerializeField] private int maxPerPrefabPoolSize = 3;
        
        [Tooltip("Total maximum pool size across all prefab types")]
        [SerializeField] private int totalMaxPoolSize = 15;

        [Header("Layer Settings")]
        [Tooltip("Layer mask for tile collision detection during spawn position validation")]
        [SerializeField] private LayerMask tileLayerMask = -1; // Let user configure which layers to avoid

        [Tooltip("Target layer for spawned obstacles - obstacles will be placed on this layer")]
        [SerializeField] private int obstacleLayer = 11; // Default to layer 11, but configurable

        [Header("Events")]
        [Tooltip("Called when an obstacle is spawned")]
        public UnityEvent<GameObject> onObstacleSpawned;
        
        [Tooltip("Called when an obstacle is returned to pool")]
        public UnityEvent<GameObject> onObstacleDestroyed;

        // Private fields
        private ObstaclePool _obstaclePool;
        private Camera _mainCamera;
        private float _screenBottom;
        private float _spawnRangeX;
        private Coroutine _spawnCoroutine;
        private readonly List<GameObject> _activeObstacles = new List<GameObject>();
        private int _obstacleCounter = 0; // Counter for unique obstacle naming

        private void Awake()
        {
            _mainCamera = Camera.main;
            
            // Validate obstacle prefabs
            ValidateObstaclePrefabs();
            
            if (useObjectPooling)
            {
                InitializeObjectPool();
            }
        }

        private void Start()
        {
            CalculateScreenBounds();
            StartSpawning();
        }

        private void OnDestroy()
        {
            StopSpawning();
        }

        /// <summary>
        /// Validates that all prefabs have required components
        /// </summary>
        private void ValidateObstaclePrefabs()
        {
            for (int i = 0; i < obstaclePrefabs.Count; i++)
            {
                if (obstaclePrefabs[i] == null) continue;
                
                // Check if the prefab has a FloatingObstacle component
                if (obstaclePrefabs[i].GetComponent<FloatingObstacle>() == null)
                {
                    Debug.LogWarning($"Obstacle prefab {obstaclePrefabs[i].name} does not have a FloatingObstacle component. Adding one automatically.");
                    obstaclePrefabs[i].AddComponent<FloatingObstacle>();
                }
                
                // Ensure the prefab is on the correct layer (using configurable obstacleLayer)
                if (obstaclePrefabs[i].layer != obstacleLayer)
                {
                    Debug.LogWarning($"Obstacle prefab {obstaclePrefabs[i].name} is not on the configured obstacle layer ({obstacleLayer}). Setting layer automatically.");
                    SetLayerRecursively(obstaclePrefabs[i], obstacleLayer);
                }
            }
        }

        /// <summary>
        /// Sets the layer of a GameObject and all its children
        /// </summary>
        private void SetLayerRecursively(GameObject obj, int layer)
        {
            obj.layer = layer;
            foreach (Transform child in obj.transform)
            {
                SetLayerRecursively(child.gameObject, layer);
            }
        }

        /// <summary>
        /// Initialize the object pool system
        /// </summary>
        private void InitializeObjectPool()
        {
            GameObject poolGO = new GameObject("ObstaclePool");
            poolGO.transform.SetParent(transform);
            _obstaclePool = poolGO.AddComponent<ObstaclePool>();
            
            // Set up pool configuration
            _obstaclePool.maxPerPrefabPoolSize = maxPerPrefabPoolSize;
            _obstaclePool.totalMaxPoolSize = totalMaxPoolSize;
            
            // Convert GameObject list to FloatingObstacle list
            List<FloatingObstacle> prefabObstacles = new List<FloatingObstacle>(obstaclePrefabs.Count);
            foreach (var prefab in obstaclePrefabs)
            {
                if (prefab != null)
                {
                    FloatingObstacle obstacleComponent = prefab.GetComponent<FloatingObstacle>();
                    if (obstacleComponent != null)
                    {
                        prefabObstacles.Add(obstacleComponent);
                    }
                    else
                    {
                        Debug.LogError($"Obstacle prefab {prefab.name} is missing a FloatingObstacle component!");
                    }
                }
            }
            
            // Initialize the pool
            _obstaclePool.Initialize(prefabObstacles);
        }

        /// <summary>
        /// Calculate screen bounds in world space dynamically
        /// </summary>
        private void CalculateScreenBounds()
        {
            if (_mainCamera == null)
            {
                _mainCamera = Camera.main;
                if (_mainCamera == null)
                {
                    Debug.LogError("[ObstacleSpawner] No main camera found!");
                    return;
                }
            }

            // Calculate screen bottom (Y spawn position will be 2 units below this)
            Vector3 bottomWorldPoint = _mainCamera.ViewportToWorldPoint(new Vector3(0.5f, 0f, _mainCamera.nearClipPlane));
            _screenBottom = bottomWorldPoint.y;

            // Calculate screen width in world units
            Vector3 leftWorldPoint = _mainCamera.ViewportToWorldPoint(new Vector3(0f, 0.5f, _mainCamera.nearClipPlane));
            Vector3 rightWorldPoint = _mainCamera.ViewportToWorldPoint(new Vector3(1f, 0.5f, _mainCamera.nearClipPlane));
            float screenWidth = rightWorldPoint.x - leftWorldPoint.x;
            
            // Calculate spawn range based on 80% of screen width (40% on each side from center)
            _spawnRangeX = (screenWidth * 0.8f) / 2f;
            
            Debug.Log($"[ObstacleSpawner] Screen calculated - Width: {screenWidth:F2}, Bottom: {_screenBottom:F2}, Spawn Range X: ±{_spawnRangeX:F2}");
        }

        /// <summary>
        /// Starts the obstacle spawning coroutine
        /// </summary>
        public void StartSpawning()
        {
            if (_spawnCoroutine == null)
            {
                _spawnCoroutine = StartCoroutine(SpawnObstaclesCoroutine());
                Debug.Log("[ObstacleSpawner] Started spawning obstacles");
            }
        }

        /// <summary>
        /// Stops the obstacle spawning coroutine
        /// </summary>
        public void StopSpawning()
        {
            if (_spawnCoroutine != null)
            {
                StopCoroutine(_spawnCoroutine);
                _spawnCoroutine = null;
                Debug.Log("[ObstacleSpawner] Stopped spawning obstacles");
            }
        }

        /// <summary>
        /// Main spawning coroutine that runs continuously
        /// </summary>
        private IEnumerator SpawnObstaclesCoroutine()
        {
            while (true)
            {
                // Calculate next spawn time with variation
                float nextSpawnTime = spawnInterval + Random.Range(-spawnIntervalVariation, spawnIntervalVariation);
                nextSpawnTime = Mathf.Max(0.1f, nextSpawnTime); // Ensure minimum interval
                
                yield return new WaitForSeconds(nextSpawnTime);
                
                // Attempt to spawn an obstacle
                TrySpawnObstacle();
            }
        }

        /// <summary>
        /// Attempts to spawn an obstacle at a valid position
        /// </summary>
        private void TrySpawnObstacle()
        {
            Debug.Log($"[ObstacleSpawner] TrySpawnObstacle called at {Time.time:F2}");
            
            if (obstaclePrefabs == null || obstaclePrefabs.Count == 0)
            {
                Debug.LogWarning("[ObstacleSpawner] No obstacle prefabs available for spawning!");
                return;
            }

            Vector3 spawnPosition;
            bool foundValidPosition = false;

            // Try to find a valid spawn position
            for (int attempts = 0; attempts < maxSpawnAttempts; attempts++)
            {
                spawnPosition = GetRandomSpawnPosition();
                
                if (IsValidSpawnPosition(spawnPosition))
                {
                    Debug.Log($"[ObstacleSpawner] Found valid position at {spawnPosition} after {attempts + 1} attempts");
                    SpawnObstacleAt(spawnPosition);
                    foundValidPosition = true;
                    break;
                }
                else
                {
                    Debug.Log($"[ObstacleSpawner] Position {spawnPosition} invalid (attempt {attempts + 1}/{maxSpawnAttempts})");
                }
            }

            if (!foundValidPosition)
            {
                Debug.LogWarning($"[ObstacleSpawner] SPAWN MISSED: Could not find valid spawn position after {maxSpawnAttempts} attempts at {Time.time:F2}");
            }
        }

        /// <summary>
        /// Gets a random spawn position below the screen
        /// </summary>
        private Vector3 GetRandomSpawnPosition()
        {
            // Use dynamically calculated spawn range (80% of screen width)
            float randomX = Random.Range(-_spawnRangeX, _spawnRangeX);
            // Spawn 2 units below screen bottom
            float spawnY = _screenBottom - 2f;

            return new Vector3(randomX, spawnY, 0f);
        }

        /// <summary>
        /// Checks if a spawn position is valid (not colliding with tiles)
        /// </summary>
        private bool IsValidSpawnPosition(Vector3 position)
        {
            // Use OverlapCircle to check for collisions with tiles
            Collider2D collision = Physics2D.OverlapCircle(position, spawnCollisionRadius, tileLayerMask);
            return collision == null;
        }

        /// <summary>
        /// Spawns an obstacle at the specified position
        /// </summary>
        private void SpawnObstacleAt(Vector3 position)
        {
            Debug.Log($"[ObstacleSpawner] SpawnObstacleAt called for position {position}");
            
            // Select random prefab
            int prefabIndex = Random.Range(0, obstaclePrefabs.Count);
            GameObject prefab = obstaclePrefabs[prefabIndex];
            
            if (prefab == null)
            {
                Debug.LogError($"[ObstacleSpawner] SPAWN FAILED: Obstacle prefab at index {prefabIndex} is null!");
                return;
            }

            GameObject obstacle;

            // Spawn using pool or instantiate directly
            if (useObjectPooling && _obstaclePool != null)
            {
                Debug.Log($"[ObstacleSpawner] Requesting obstacle from pool (prefab index {prefabIndex})");
                obstacle = _obstaclePool.GetObstacle(prefabIndex);
                if (obstacle == null)
                {
                    Debug.LogError($"[ObstacleSpawner] SPAWN FAILED: Failed to get obstacle from pool for prefab index {prefabIndex}!");
                    return;
                }
                
                Debug.Log($"[ObstacleSpawner] Got obstacle {obstacle.name} from pool, active state: {obstacle.activeInHierarchy}");
                
                // FORCE ACTIVATION - bypass pool issues
                if (!obstacle.activeInHierarchy)
                {
                    Debug.LogWarning($"[ObstacleSpawner] Pool returned inactive object {obstacle.name}, force activating!");
                    obstacle.SetActive(true);
                    Debug.Log($"[ObstacleSpawner] After force activation, {obstacle.name} active state: {obstacle.activeInHierarchy}");
                }
                
                obstacle.transform.position = position;
                obstacle.transform.rotation = prefab.transform.rotation;
                obstacle.transform.SetParent(transform);
                Debug.Log($"[ObstacleSpawner] After positioning, obstacle {obstacle.name} active state: {obstacle.activeInHierarchy}");
            }
            else
            {
                Debug.Log($"[ObstacleSpawner] Instantiating new obstacle (pooling disabled)");
                obstacle = Instantiate(prefab, position, prefab.transform.rotation, transform);
            }

            // Assign unique name with counter
            _obstacleCounter++;
            string oldName = obstacle.name;
            obstacle.name = $"Obstacle{_obstacleCounter:D3}";
            Debug.Log($"[ObstacleSpawner] Renamed obstacle from '{oldName}' to '{obstacle.name}', active state: {obstacle.activeInHierarchy}");

            // Configure the obstacle
            ConfigureObstacle(obstacle, prefabIndex);
            Debug.Log($"[ObstacleSpawner] After configuration, obstacle {obstacle.name} active state: {obstacle.activeInHierarchy}");
            
            // Track active obstacles
            _activeObstacles.Add(obstacle);
            
            // Invoke events
            onObstacleSpawned?.Invoke(obstacle);
            Debug.Log($"[ObstacleSpawner] After events, obstacle {obstacle.name} active state: {obstacle.activeInHierarchy}");
            
            Debug.Log($"[ObstacleSpawner] Successfully spawned obstacle {obstacle.name} at {position}. Active count: {_activeObstacles.Count}, Final active state: {obstacle.activeInHierarchy}");
        }

        /// <summary>
        /// Configures an obstacle with randomized properties
        /// </summary>
        private void ConfigureObstacle(GameObject obstacle, int prefabIndex)
        {
            FloatingObstacle obstacleComponent = obstacle.GetComponent<FloatingObstacle>();
            if (obstacleComponent != null)
            {
                // Set prefab index
                obstacleComponent.PrefabIndex = prefabIndex;
                
                // Randomize properties
                obstacleComponent.MoveSpeed = Random.Range(minMoveSpeed, maxMoveSpeed);
                
                // Set spawner reference (since FloatingObstacle has this built-in now)
                obstacleComponent.SetSpawner(this);
            }
        }

        /// <summary>
        /// Returns an obstacle to the pool (called by FloatingObstacle)
        /// </summary>
        public void ReturnObstacleToPool(GameObject obstacle, int prefabIndex)
        {
            if (obstacle == null) return;

            Debug.Log($"[ObstacleSpawner] ReturnObstacleToPool called for {obstacle.name}, active state: {obstacle.activeInHierarchy}");

            // Remove from active list
            _activeObstacles.Remove(obstacle);

            // Invoke events
            onObstacleDestroyed?.Invoke(obstacle);

            // Return to pool or destroy
            if (useObjectPooling && _obstaclePool != null)
            {
                Debug.Log($"[ObstacleSpawner] Returning {obstacle.name} to pool");
                _obstaclePool.ReturnObstacle(obstacle, prefabIndex);
            }
            else
            {
                Debug.Log($"[ObstacleSpawner] Destroying {obstacle.name} (pooling disabled)");
                Destroy(obstacle);
            }
        }

        /// <summary>
        /// Public method to change spawn interval at runtime
        /// </summary>
        public void SetSpawnInterval(float interval)
        {
            spawnInterval = interval;
        }

        /// <summary>
        /// Public method to change spawn range at runtime
        /// </summary>
        public void SetSpawnRange(float range)
        {
            spawnRangeX = range;
        }

        /// <summary>
        /// Public method to set speed range at runtime
        /// </summary>
        public void SetSpeedRange(float min, float max)
        {
            minMoveSpeed = min;
            maxMoveSpeed = max;
        }

        /// <summary>
        /// Public method to recalculate screen bounds (useful if camera changes)
        /// </summary>
        public void RecalculateScreenBounds()
        {
            CalculateScreenBounds();
        }

        /// <summary>
        /// Gets the count of currently active obstacles
        /// </summary>
        public int ActiveObstacleCount => _activeObstacles.Count;

#if UNITY_EDITOR
        private void OnDrawGizmosSelected()
        {
            // Only draw if screen bounds have been calculated
            if (_spawnRangeX > 0f)
            {
                // Draw spawn area using dynamic calculations
                Gizmos.color = Color.yellow;
                Vector3 center = new Vector3(0f, _screenBottom - 2f, 0f);
                Vector3 size = new Vector3(_spawnRangeX * 2f, 1f, 1f);
                Gizmos.DrawWireCube(center, size);
                
                // Draw collision radius at spawn point
                Gizmos.color = Color.red;
                Gizmos.DrawWireSphere(center, spawnCollisionRadius);
            }
        }
#endif
    }
}