/// Rohmer Maxime <maxluligames@gmail.com>
/// 28 April 2022
/// TileMap.cs
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace WaveFunctionCollapseCLI
{
    // The TileMap will contain all the WaveFunctionColllapse
    internal class TileMap
    {
        private Size _dimensions;
        private Tile[,] _tiles;

        public Size Dimensions { get => _dimensions; set => _dimensions = value; }
        internal Tile[,] Tiles { get => _tiles; set => _tiles = value; }

        public TileMap(Size dimensions, List<TileType> avaibleTypes)
        {
            Dimensions = dimensions;

            Tiles = new Tile[Dimensions.Width, Dimensions.Height];
            for (int x = 0; x < Dimensions.Width; x++)
            {
                for (int y = 0; y < Dimensions.Height; y++)
                {
                    Tiles[x, y] = new Tile(avaibleTypes);
                }
            }
        }

        public void NextStep()
        {
            Random rnd = new Random();
            List<Tile> lowestEntropyTiles = new List<Tile>();
            int lowestEntropy = -1;

            foreach (Tile t in Tiles)
            {
                int tileEntropy = t.PossibleTyles.Count;

                if (lowestEntropy == -1)
                {
                    //checks if its the first tile
                    lowestEntropy = tileEntropy;
                    lowestEntropyTiles.Add(t);
                }
                else
                {
                    if (lowestEntropy > tileEntropy)
                    {
                        lowestEntropy = tileEntropy;
                        lowestEntropyTiles.Clear();
                        lowestEntropyTiles.Add(t);
                    }
                    else
                    {
                        if (lowestEntropy == tileEntropy)
                        {
                            lowestEntropyTiles.Add(t);
                        }
                    }
                }

                //the list contains all the tyles that have exactly the same entropy 
                //now we can randomly select one and set one of the posssible types and set it, then we need to recursively change everything

                int tileCount = lowestEntropyTiles.Count;

                int tileIndex = rnd.Next(0, tileCount);
                List<TileType> options = lowestEntropyTiles[tileIndex].PossibleTyles;

                int optionCount = options.Count();
                if (optionCount > 0)
                {
                    int idx = rnd.Next(0, optionCount);
                    lowestEntropyTiles[tileIndex].PossibleTyles = new List<TileType> { options[idx] };
                }

                Wave();

            }
        }
        private void Wave()
        {
            // we need to iterate trough the map to update every possibleTile every tile can have with the modified array
            // each pass can mean more tile to refresh so we need to do it until a pass does not change the array
            //for that we also need to deep copy it 

            // Tiles and tiletypes have implemented clone

            Tile[,] oldTiles = new Tile[Dimensions.Width,Dimensions.Height];
            //while (!oldTiles.Equals(Tiles))
            {
                oldTiles = (Tile[,])Tiles.Clone();
                for (int x = 0; x < Dimensions.Width; x++)
                {
                    for (int y = 0; y < Dimensions.Height; y++)
                    {
                        CheckNeighbours(x, y);
                    }
                }
            }

        }
        private void CheckNeighbours(int x, int y)
        {
            //checks that the tile is not on a corner
            List<Tile> Neighbours = new List<Tile>();
            Tile target = Tiles[x, y];
            if (x > 0 && x < Dimensions.Width - 1 && y > 0 && y < Dimensions.Height - 1)
            {
                Neighbours.Add(Tiles[x, y - 1]);    //Top
                Neighbours.Add(Tiles[x, y + 1]);    //Bottom
                Neighbours.Add(Tiles[x - 1, y]);     //Left
                Neighbours.Add(Tiles[x + 1, y]);    //Right
            }
            else
            {
                //TODO
            }

            List<TileType> typesToRemove = new List<TileType>();
            foreach (Tile t in Neighbours)
            {
                typesToRemove.Clear();
                foreach (TileType tyleType in t.PossibleTyles)
                {
                    bool typePossible = false;
                    foreach (TileType targetTyleType in target.PossibleTyles)
                    {
                        if (!tyleType.IsCompatible(targetTyleType))
                        {
                            typePossible = true;
                        }
                    }
                    if (!typePossible)
                    {
                        typesToRemove.Add(tyleType);
                    }
                }
                foreach (TileType toRmv in typesToRemove)
                {
                    t.PossibleTyles.Remove(toRmv);
                }
            }
        }
        public void Display(List<TileType> types, List<ConsoleColor> colors)
        {
            Console.Write("\n");
            char sprite = '#';
            for (int x = 0; x < Dimensions.Width; x++)
            {
                for (int y = 0; y < Dimensions.Height; y++)
                {
                    //we check if there only is one possibility 
                    if (Tiles[x, y].PossibleTyles.Count < 2)
                    {
                        //Console.BackgroundColor = colors[types.IndexOf(new TileType(Tiles[x, y].PossibleTyles[0].Name))];
                        //Console.ForegroundColor = colors[types.IndexOf(new TileType(Tiles[x, y].PossibleTyles[0].Name))];

                        int idxColor = 0;
                        for (int i = 0;i < types.Count;i++)
                        {
                            if (Tiles[x, y].PossibleTyles.Count > 0)
                            {
                                if (types[i].Name == Tiles[x, y].PossibleTyles[0].Name)
                                {
                                    idxColor = i;
                                }
                            }
                        }
                        Console.ForegroundColor = colors[idxColor];
                    }
                    else
                    {
                        //this means that we need other steps to determinate wich Tile to use
                        //Console.BackgroundColor = ConsoleColor.Gray;
                        Console.ForegroundColor = ConsoleColor.Gray;
                    }
                    Console.Write(sprite);
                }
                Console.Write("\n");
            }
        }
    }

}