using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Utils = KairoEngine.Utility.Utilities;
using TMPro;

namespace KairoEngine.Grids
{
    public enum GridPlane
    {
        XY,
        XZ,
        YZ
    }

    public class Grid<TGridObject>
    {
        

        private int width;
        private int height;
        private float cellSize;
        private Vector3 originPosition;
        private bool debug = false;

        private GridPlane plane = GridPlane.XY;

        private TGridObject[,] gridArray;
        private TextMesh[,] debugTextArray;

        public event EventHandler<OnGridObjectChangedEventArgs> OnGridObjectChanged;
        public class OnGridObjectChangedEventArgs : EventArgs 
        {
            public int x;
            public int y;
        }

        public Grid(int width, int height, float cellSize, Vector3 originPosition, Func<Grid<TGridObject>, int, int, TGridObject> createGridObject, 
            GridPlane plane = GridPlane.XY, bool debug = false)
        {
            this.width = width;
            this.height = height;
            this.cellSize = cellSize;
            this.originPosition = originPosition;
            this.gridArray = new TGridObject[width, height];
            this.debug = debug;
            this.plane = plane;

            for (int x = 0; x < gridArray.GetLength(0); x++)
            {
                for (int y = 0; y < gridArray.GetLength(1); y++)
                {
                    gridArray[x, y] = createGridObject(this, x, y);
                }
            }
            UpdateDebugView();
        }

        public int GetWidth() => width;
        public int GetHeight() => height;
        public float GetCellSize() => cellSize;

        public Vector3 GetWorldPosition(int x, int y)
        {
            switch(plane)
            {
                case GridPlane.XY:
                    return new Vector3(x, y, 0) * cellSize + originPosition;
                case GridPlane.XZ:
                    return new Vector3(x, 0, y) * cellSize + originPosition;
                case GridPlane.YZ:
                    return new Vector3(0, x, y) * cellSize + originPosition;
                default:
                    return new Vector3();
            }
        }

        public void GetGridPosition(Vector3 worldPosition, out int x, out int y)
        {
            x = 0;
            y = 0;
            switch(plane)
            {
                case GridPlane.XY:
                    x = Mathf.FloorToInt((worldPosition - originPosition).x/ cellSize);
                    y = Mathf.FloorToInt((worldPosition - originPosition).y / cellSize);
                    break;
                case GridPlane.XZ:
                    x = Mathf.FloorToInt((worldPosition - originPosition).x/ cellSize);
                    y = Mathf.FloorToInt((worldPosition - originPosition).z / cellSize);
                    break;
                case GridPlane.YZ:
                    x = Mathf.FloorToInt((worldPosition - originPosition).y/ cellSize);
                    y = Mathf.FloorToInt((worldPosition - originPosition).z / cellSize);
                    break;
                default:
                    break;
            }
        }

        public bool IsPositionInsideGrid(Vector2Int gridPosition)
        {
            if(gridPosition.x < 0) return false;
            if(gridPosition.x > width - 1) return false;
            if(gridPosition.y < 0) return false;
            if(gridPosition.y > height - 1) return false;
            return true;
        }

        public bool IsPositionInsideGrid(Vector3 worldPosition)
        {
            float maxWidth, maxHeight;
            switch(plane)
            {
                case GridPlane.XY:
                    maxWidth = originPosition.x + (cellSize * width);
                    maxHeight = originPosition.y + (cellSize * height);
                    if(worldPosition.x > maxWidth) return false;
                    if(worldPosition.x < originPosition.x) return false;
                    if(worldPosition.y > maxHeight) return false;
                    if(worldPosition.y < originPosition.y) return false;
                    break;
                case GridPlane.XZ:
                    maxWidth = originPosition.x + (cellSize * width);
                    maxHeight = originPosition.z + (cellSize * height);
                    if(worldPosition.x > maxWidth) return false;
                    if(worldPosition.x < originPosition.x) return false;
                    if(worldPosition.z > maxHeight) return false;
                    if(worldPosition.z < originPosition.z) return false;
                    break;
                case GridPlane.YZ:
                    maxWidth = originPosition.y + (cellSize * width);
                    maxHeight = originPosition.z + (cellSize * height);
                    if(worldPosition.y > maxWidth) return false;
                    if(worldPosition.y < originPosition.y) return false;
                    if(worldPosition.z > maxHeight) return false;
                    if(worldPosition.z < originPosition.z) return false;
                    break;
                default:
                    break;
            }
            return true;
        }

        public void SetObject(int x, int y, TGridObject value)
        {
            if(x >= 0 && y >= 0 && x < width && y < height)
            {
                gridArray[x, y] = value;
                if(debug) debugTextArray[x, y].text = gridArray[x, y].ToString();
                TriggerGridObjectChanged(x, y);
            }
        }

        public void SetObject(Vector3 worldPosition, TGridObject value)
        {
            int x, y;
            GetGridPosition(worldPosition, out x, out y);
            SetObject(x, y, value);
        }

        public TGridObject GetObject(int x, int y)
        {
            if(x >= 0 && y >= 0 && x < width && y < height)
            {
                return gridArray[x, y];
            }
            else return default(TGridObject);
        }

        public TGridObject GetObject(Vector3 worldPosition)
        {
            int x, y;
            GetGridPosition(worldPosition, out x, out y);
            return GetObject(x, y);
        } 

        public Vector3 GetQuadSize()
        {
            switch(plane)
            {
                case GridPlane.XY:
                    return new Vector3(1, 1, 0) * GetCellSize();
                case GridPlane.XZ:
                    return new Vector3(1, 0, 1) * GetCellSize();
                case GridPlane.YZ:
                    return new Vector3(0, 1, 1) * GetCellSize();
                default:
                    return new Vector3(0, 0, 0);
            }
        }

        public GridPlane GetGridPlane() => plane;

        public void TriggerGridObjectChanged(int x, int y)
        {
            if(OnGridObjectChanged != null) OnGridObjectChanged(this, new OnGridObjectChangedEventArgs {x = x, y = y});
            UpdateDebugView();
        }

        private void UpdateDebugView()
        {
            DestroyDebugText();
            if(debug)
            {
                this.debugTextArray = new TextMesh[width, height];

                for (int x = 0; x < gridArray.GetLength(0); x++)
                {
                    for (int y = 0; y < gridArray.GetLength(1); y++)
                    {
                        debugTextArray[x, y] = Utils.CreateWorldText(gridArray[x,y]?.ToString(), null, GetWorldPosition(x, y) + GetQuadSize() * .5f, 
                            12, Color.white, TextAnchor.MiddleCenter);
                        Debug.DrawLine(GetWorldPosition(x, y), GetWorldPosition(x, y + 1), Color.white, 100f);
                        Debug.DrawLine(GetWorldPosition(x, y), GetWorldPosition(x + 1, y), Color.white, 100f);
                    }
                }
                Debug.DrawLine(GetWorldPosition(0, height), GetWorldPosition(width, height), Color.white, 100f);
                Debug.DrawLine(GetWorldPosition(width, 0), GetWorldPosition(width, height), Color.white, 100f);
            }
        }

        private void DestroyDebugText()
        {
            if(this.debugTextArray != null)
            {
                for (int x = 0; x < this.debugTextArray.GetLength(0); x++)
                {
                    for (int y = 0; y < this.debugTextArray.GetLength(1); y++)
                    {
                        GameObject.Destroy(debugTextArray[x,y].gameObject);
                    }
                }
            }
        }
    }

    
}