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

namespace Hallucinate.GameSetup.Maze
{
    /// <summary>
    /// Responsible for the visual representation of the maze.
    /// Handles spawning, pooling, and animations.
    /// </summary>
    public class MazeRenderer : MonoBehaviour
    {
        [SerializeField] private MazeVisualProfile visualProfile;
        
        private readonly Dictionary<Vector2Int, GameObject> _spawnedCells = new Dictionary<Vector2Int, GameObject>();
        private Transform _container;

        public void Initialize(MazeGrid grid, Transform container)
        {
            _container = container;
            grid.OnCellChanged += HandleCellChanged;
            
            // Initial render
            for (int z = 0; z < grid.Depth; z++)
            {
                for (int x = 0; x < grid.Width; x++)
                {
                    UpdateCellVisual(x, z, grid.GetCell(x, z), false);
                }
            }
        }

        public void Clear()
        {
            // IMPORTANT: Stop all running animations to prevent accessing destroyed objects
            StopAllCoroutines();

            foreach (var cell in _spawnedCells.Values)
            {
                if (cell != null) Destroy(cell);
            }
            _spawnedCells.Clear();
        }

        private void HandleCellChanged(int x, int z, MazeCellType type)
        {
            UpdateCellVisual(x, z, type, true);
        }

        private void UpdateCellVisual(int x, int z, MazeCellType type, bool animate)
        {
            Vector2Int pos = new Vector2Int(x, z);
            
            // Remove old visual if exists
            if (_spawnedCells.TryGetValue(pos, out GameObject oldObj))
            {
                Destroy(oldObj);
                _spawnedCells.Remove(pos);
            }

            GameObject prefab = visualProfile.GetPrefab(type);
            if (prefab == null) return;

            Vector3 worldPos = new Vector3(x * visualProfile.scale, 0, z * visualProfile.scale);
            GameObject newObj = Instantiate(prefab, worldPos, Quaternion.identity, _container);
            newObj.transform.localScale = Vector3.one * visualProfile.scale;
            _spawnedCells[pos] = newObj;

            if (animate)
            {
                StartCoroutine(AnimateCell(newObj.transform));
            }
        }

        private IEnumerator AnimateCell(Transform target)
        {
            if (target == null) yield break;

            float duration = visualProfile.animationDuration;
            float elapsed = 0;
            Vector3 finalScale = target.localScale;
            target.localScale = Vector3.zero;

            while (elapsed < duration)
            {
                // Extra safety check in case the object is destroyed mid-animation
                if (target == null) yield break;

                elapsed += Time.deltaTime;
                float t = elapsed / duration;
                float s = Mathf.Sin(t * Mathf.PI * 0.5f); 
                target.localScale = finalScale * s;
                yield return null;
            }

            if (target != null)
            {
                target.localScale = finalScale;
            }
        }
    }
}