using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using KairoEngine.Utility;

namespace KairoEngine.Grids
{
    public class HeatMapVisual : MonoBehaviour
    {
        private Grid<HeatMapGridObject> grid;
        private Mesh mesh;

        private bool updateMesh = false;
        
        private void Awake()
        {
            mesh = new Mesh();
            GetComponent<MeshFilter>().mesh = mesh;
        }

        public void SetGrid(Grid<HeatMapGridObject> grid) 
        {
            this.grid = grid;
            UpdateHeatMapVisual();
            grid.OnGridObjectChanged += Grid_OnGridObjectChanged;
        }

        private void UpdateHeatMapVisual()
        {
            MeshUtils.CreateEmptyMeshArrays(grid.GetWidth() * grid.GetHeight(), out Vector3[] vertices, out Vector2[] uv, out int[] triangles);
            for (int x = 0; x < grid.GetWidth(); x++)
            {
                for (int y = 0; y < grid.GetHeight(); y++)
                {
                    int index = x * grid.GetHeight() + y;
                    Vector3 quadSize = grid.GetQuadSize();
                    HeatMapGridObject gridObject = grid.GetObject(x, y);
                    Vector2 gridValueUV = new Vector2(gridObject.GetValueNormalized(), 0f);
                    Vector3 pos = grid.GetWorldPosition(x, y) + (quadSize * 0.5f);
                    float rot = 0f;
                    MeshUtils.AddToMeshArrays(vertices, uv, triangles, index, pos, rot, quadSize, gridValueUV, gridValueUV);
                }
            }
            mesh.vertices = vertices;
            mesh.uv = uv;
            mesh.triangles = triangles;
        }

        private void Grid_OnGridObjectChanged(object sender, Grid<HeatMapGridObject>.OnGridObjectChangedEventArgs e) => updateMesh = true;

        private void LateUpdate()
        {
            if(updateMesh)
            {
                updateMesh = false;
                Debug.Log("Grid event fired");
                UpdateHeatMapVisual();
            }
        }

        public void AddValue(int x, int y, int value)
        {
            HeatMapGridObject obj =  grid.GetObject(x, y);
            if(obj != null)
            {
                obj.AddValue(value);
                //grid.SetObject(x, y, obj);
            }
        }

        public void AddValue(Vector3 worldPosition, int value, int fullValueRange, int totalRange)
        {
            int lowerValueAmmount = Mathf.RoundToInt((float)value / (totalRange - fullValueRange));
            grid.GetGridPosition(worldPosition, out int originX, out int originY);
            for (int x = 0; x < totalRange; x++)
            {
                for (int y = 0; y < totalRange - x; y++)
                {
                    int radius = x + y;
                    int addValueAmmount = value;
                    if(radius > fullValueRange) addValueAmmount -= lowerValueAmmount * (radius - fullValueRange);
                    AddValue(originX + x, originY + y, addValueAmmount);
                    if(x != 0) AddValue(originX - x, originY + y, addValueAmmount);
                    if(y != 0) AddValue(originX + x, originY - y, addValueAmmount);
                    if(y != 0 && x != 0) AddValue(originX - x, originY - y, addValueAmmount);
                }
            }
        }
    }

    public class HeatMapGridObject 
    {
        private const int MIN = 0;
        private const int MAX = 100;
        private Grid<HeatMapGridObject> grid;
        private int x;
        private int y;
        public int value;

        public HeatMapGridObject(Grid<HeatMapGridObject> grid, int x, int y)
        {
            this.grid = grid;
            this.x = x;
            this.y = y;
        }

        public void AddValue(int addValue)
        {
            value += addValue;
            value = Mathf.Clamp(value, MIN, MAX);
            grid.TriggerGridObjectChanged(x, y);
        }

        public float GetValueNormalized() => (float)value / MAX;

        public override string ToString() => value.ToString();

    }

}