using System.Collections;
using System.Collections.Generic;
using Sirenix.OdinInspector;
using UnityEngine;

namespace Hallucinate.GameSetup.Maze
{
    /// <summary>
    /// Central controller for the Maze system.
    /// Manages algorithm selection, debug speed, and regeneration.
    /// </summary>
    public class MazeManager : MonoBehaviour
    {
        public enum AlgorithmType { Recursive, Wilsons, Prims, Crawler, NoiseRecursive }

        [BoxGroup("Generation")]
        [InfoBox("Set the array size to control how many maze floors are generated. Runtime grid data is rebuilt when Regenerate runs.")]
        [ValidateInput(nameof(HasAtLeastOneFloor), "Maze Manager needs at least one floor.")]
        public MazeGrid[] mazes;

        [BoxGroup("Generation")]
        [MinValue(0.001f)]
        public float floorHeight = 3.5f;

        [BoxGroup("Generation")]
        [MinValue(0)]
        public int connectionsPerFloor = 2;

        [BoxGroup("Generation")]
        [SerializeField] private AlgorithmType selectedAlgorithm;

        [BoxGroup("Generation/Grid Size")]
        [PropertyRange(5, 200)]
        [SerializeField] private int width = 30;

        [BoxGroup("Generation/Grid Size")]
        [PropertyRange(5, 200)]
        [SerializeField] private int depth = 30;
        
        [BoxGroup("Animation")]
        [SerializeField] private bool animateGeneration = true;

        [BoxGroup("Animation")]
        [ShowIf(nameof(animateGeneration))]
        [PropertyRange(1, 500)]
        [LabelText("Generation Speed (Cells/Frame)")]
        [SerializeField] private int generationSpeed = 50;

        public static int cellsProcessedThisFrame;

        [BoxGroup("Animation")]
        [ShowIf(nameof(animateGeneration))]
        public MazeRenderer.CellAnimationType cellAnimationType = MazeRenderer.CellAnimationType.ScaleUp;

        [BoxGroup("Progress")]
        [ProgressBar(0, 100)]
        [ShowInInspector, ReadOnly]
        private float completionPercentage;

        [BoxGroup("References")]
        [Required]
        [SerializeField] private MazeRenderer mazeRenderer;

        [BoxGroup("Rooms (Phase 2)")]
        public bool generateRooms = true;
        [BoxGroup("Rooms (Phase 2)")]
        [ShowIf(nameof(generateRooms))]
        public int numberOfRooms = 2;
        [BoxGroup("Rooms (Phase 2)")]
        [ShowIf(nameof(generateRooms))]
        public Vector2Int minRoomSize = new Vector2Int(2, 2);
        [BoxGroup("Rooms (Phase 2)")]
        [ShowIf(nameof(generateRooms))]
        public Vector2Int maxRoomSize = new Vector2Int(4, 4);

        [BoxGroup("References")]
        [Required]
        [SerializeField] private Transform mazeContainer;

        [FoldoutGroup("Manhole Prefabs")]
        public GameObject straightManHoleLadder;
        [FoldoutGroup("Manhole Prefabs")]
        public GameObject straightManHoleUp;
        [FoldoutGroup("Manhole Prefabs")]
        public GameObject deadendManHoleLadder;
        [FoldoutGroup("Manhole Prefabs")]
        public GameObject deadendManHoleUp;

        [ShowInInspector]
        [ReadOnly]
        [BoxGroup("Runtime")]
        private int FloorCount => mazes?.Length ?? 0;

        [ShowInInspector]
        [ReadOnly]
        [BoxGroup("Runtime")]
        private string CurrentGrid => _grid == null ? "None" : $"{_grid.Width}x{_grid.Depth}, Level {_grid.Level}";

        private MazeGrid _grid;
        private Coroutine _generationCoroutine;
        private HashSet<Vector3Int> _modifiedCells = new HashSet<Vector3Int>();

        private void Start()
        {
            Regenerate();
        }

        private void Update()
        {
            if (Input.GetKeyDown(KeyCode.R))
            {
                Regenerate();
            }
        }

        [ContextMenu("Clear Maze")]
        [Button("Clear Maze", ButtonSizes.Large)]
        public void ClearMaze()
        {
            if (_generationCoroutine != null)
            {
                StopCoroutine(_generationCoroutine);
                _generationCoroutine = null;
            }

            if (mazeRenderer != null)
            {
                mazeRenderer.Clear();
            }

            completionPercentage = 0f;
            _modifiedCells?.Clear();
        }

        [ContextMenu("Regenerate")]
        [Button("Regenerate Maze", ButtonSizes.Large)]
        public void Regenerate()
        {
            if (mazeRenderer == null)
            {
                Debug.LogError("MazeManager needs a MazeRenderer reference before regenerating.", this);
                return;
            }

            if (mazeContainer == null)
            {
                Debug.LogError("MazeManager needs a maze container reference before regenerating.", this);
                return;
            }

            if (mazes == null || mazes.Length == 0)
            {
                mazes = new MazeGrid[1];
            }

            ClearMaze();

            mazeRenderer.currentAnimationType = cellAnimationType;

            if (animateGeneration)
            {
                _generationCoroutine = StartCoroutine(GenerateMazeRoutine());
            }
            else
            {
                GenerateMazeInstant();
            }
        }

        private void GenerateMazeInstant()
        {
            _modifiedCells.Clear();
            completionPercentage = 0f;

            for (int i = 0; i < mazes.Length; i++)
            {
                mazes[i] = new MazeGrid(width, depth);
                mazes[i].Level = i;
                
                CarveRooms(mazes[i]);

                IMazeAlgorithm algorithmForFloor = GetAlgorithm(selectedAlgorithm);
                algorithmForFloor.Generate(mazes[i]);
            }

            GenerateConnections();

            for (int i = 0; i < mazes.Length; i++)
            {
                mazeRenderer.Initialize(mazes[i], mazeContainer, i == 0);
            }
            if (mazes.Length > 0) _grid = mazes[0];

            completionPercentage = 100f;
        }

        private IEnumerator GenerateMazeRoutine()
        {
            _modifiedCells.Clear();
            completionPercentage = 0f;

            for (int i = 0; i < mazes.Length; i++)
            {
                mazes[i] = new MazeGrid(width, depth);
                mazes[i].Level = i;
                int floorIndex = i;

                mazes[i].OnCellChanged += (x, z, type) => 
                {
                    if (type != MazeCellType.Wall)
                    {
                        _modifiedCells.Add(new Vector3Int(x, floorIndex, z));
                        int totalCells = width * depth * mazes.Length;
                        // Approximate the progress to reach roughly 100% since algorithms don't visit all cells
                        float fillRatio = 0.6f; 
                        completionPercentage = Mathf.Clamp((_modifiedCells.Count / ((float)totalCells * fillRatio)) * 100f, 0, 99f);
                    }
                };

                CarveRooms(mazes[i]);
                mazeRenderer.Initialize(mazes[i], mazeContainer, i == 0);
                
                IMazeAlgorithm algorithmForFloor = GetAlgorithm(selectedAlgorithm);
                cellsProcessedThisFrame = 0;
                yield return StartCoroutine(algorithmForFloor.GenerateStepByStep(mazes[i], generationSpeed));
            }

            GenerateConnections();

            if (mazes.Length > 0) _grid = mazes[0];

            completionPercentage = 100f;
            _generationCoroutine = null;
        }

        private void GenerateConnections()
        {
            // Step 2: Create connections between adjacent floors
            for (int i = 0; i < mazes.Length - 1; i++)
            {
                MazeGrid currentFloor = mazes[i];
                MazeGrid nextFloor = mazes[i + 1];

                List<Vector2Int> possibleConnections = new List<Vector2Int>();

                for (int z = 0; z < depth; z++)
                {
                    for (int x = 0; x < width; x++)
                    {
                        // Check if both floors have a corridor at this position
                        bool isCurrentFloorPath = currentFloor.GetCell(x, z) == MazeCellType.Corridor;
                        bool isNextFloorPath = nextFloor.GetCell(x, z) == MazeCellType.Corridor;

                        if (isCurrentFloorPath && isNextFloorPath)
                        {
                            possibleConnections.Add(new Vector2Int(x, z));
                        }
                    }
                }

                ShuffleList(possibleConnections);

                int connectionsMade = 0;
                foreach (Vector2Int pos in possibleConnections)
                {
                    if (connectionsMade >= connectionsPerFloor) break;

                    int x = pos.x;
                    int z = pos.y;

                    // Set stair cells
                    currentFloor.SetCell(x, z, MazeCellType.StairsUp);
                    nextFloor.SetCell(x, z, MazeCellType.StairsDown);

                    connectionsMade++;
                }
            }
        }

        private void CarveRooms(MazeGrid grid)
        {
            if (!generateRooms) return;

            for (int i = 0; i < numberOfRooms; i++)
            {
                int w = Random.Range(minRoomSize.x, maxRoomSize.x + 1);
                int d = Random.Range(minRoomSize.y, maxRoomSize.y + 1);
                
                int startX = Random.Range(1, width - w - 1);
                int startZ = Random.Range(1, depth - d - 1);

                for (int x = startX; x < startX + w; x++)
                {
                    for (int z = startZ; z < startZ + d; z++)
                    {
                        grid.SetCell(x, z, MazeCellType.Room);
                    }
                }

                // Carve guaranteed door to seed pathfinding
                if (Random.value > 0.5f)
                {
                    int doorX = Random.Range(startX, startX + w);
                    int doorZ = Random.value > 0.5f ? startZ + d : startZ - 1;
                    grid.SetCell(doorX, doorZ, MazeCellType.Corridor);
                }
                else
                {
                    int doorX = Random.value > 0.5f ? startX + w : startX - 1;
                    int doorZ = Random.Range(startZ, startZ + d);
                    grid.SetCell(doorX, doorZ, MazeCellType.Corridor);
                }
            }
        }

        private void ShuffleList<T>(List<T> list)
        {
            for (int i = 0; i < list.Count; i++)
            {
                T temp = list[i];
                int randomIndex = Random.Range(i, list.Count);
                list[i] = list[randomIndex];
                list[randomIndex] = temp;
            }
        }

        private IMazeAlgorithm GetAlgorithm(AlgorithmType type)
        {
            return type switch
            {
                AlgorithmType.Recursive => new RecursiveAlgorithm(),
                AlgorithmType.Wilsons => new WilsonsAlgorithm(),
                AlgorithmType.Prims => new PrimsAlgorithm(),
                AlgorithmType.Crawler => new CrawlerAlgorithm(),
                AlgorithmType.NoiseRecursive => new NoiseRecursiveGenerator(),
                _ => new RecursiveAlgorithm()
            };
        }

        [Button("Find Scene References")]
        private void FindSceneReferences()
        {
            if (mazeRenderer == null)
            {
                mazeRenderer = GetComponentInChildren<MazeRenderer>();
            }

            if (mazeContainer == null)
            {
                mazeContainer = transform;
            }
        }

        private bool HasAtLeastOneFloor(MazeGrid[] floors)
        {
            return floors != null && floors.Length > 0;
        }
    }
}