using System;
namespace test_map_generation.voronoi
{
    public struct BiomeInfo
    {
        public char type;
        public int x;
        public int y;
    }

    public struct BiomeType
    {
        public char symbol;
    }

    public class voronoi_generation
    {
        public int map_size_width;
        public int map_size_height;
        public int starterBiomeCount;

        public BiomeType[] biomeTypes;
        public BiomeInfo[] biomeCollection;

        public char[,] field;

        public voronoi_generation(int width, int height, int numStarterBiomes)
        {
            this.map_size_width = width;
            this.map_size_height = height;
            this.starterBiomeCount = numStarterBiomes;

            this.field = new char[this.map_size_width, this.map_size_height];
            this.initBoimeStarters();
        }

        public void generateMap()
        {
            for (int i = 0; i < this.map_size_height; i++)
            {
                for (int j = 0; j < this.map_size_width; j++)
                {
                    char nearest = '.'; // value here doesn't matter
                    int dist = int.MaxValue;

                    // walk over each biomeInfo
                    for (int z = 0; z < this.biomeCollection.Length; z++)
                    {

                        // calculate the difference in x and y direction
                        int xdiff = this.biomeCollection[z].x - i;
                        int ydiff = this.biomeCollection[z].y - j;

                        // calculate euclidean distance, sqrt is not needed
                        // because we only compare and do not need the real value
                        int cdist = xdiff * xdiff + ydiff * ydiff;

                        // is the current distance smaller than the old distance?
                        // if yes, take this biome
                        if (cdist < dist)
                        {
                            nearest = this.biomeCollection[z].type;
                            dist = cdist;
                        }

                        // set the field to the nearest biome
                        this.field[j,i] = nearest;
                    }
                }
            }
        }

        public void printMap()
        {
            for (int i = 0; i < this.map_size_height; i++)
            {
                String row = " ";

                for (int j = 0; j < this.map_size_width; j++)
                {
                    row += this.field[j, i].ToString();
                }
                Console.WriteLine(row);
            }
        }

        private void initBoimeStarters()
        {
            this.initBiomeTypes();

            this.biomeCollection = new BiomeInfo[this.starterBiomeCount];

            for (int i = 0; i < this.starterBiomeCount; i++)
            {
                Random rngGen = new Random();

                char biomeTypeSelected = this.biomeTypes[rngGen.Next(this.biomeTypes.Length)].symbol;
                int positionX = rngGen.Next(this.map_size_width);
                int positionY = rngGen.Next(this.map_size_height);

                this.biomeCollection[i].type = biomeTypeSelected;
                this.biomeCollection[i].x = positionX;
                this.biomeCollection[i].y = positionY;
            }
        }

        public void initBiomeTypes()
        {
            this.biomeTypes = new BiomeType[8];

            this.biomeTypes[0].symbol = '#';
            this.biomeTypes[1].symbol = 'O';
            this.biomeTypes[2].symbol = '?';
            this.biomeTypes[3].symbol = 'x';
            this.biomeTypes[4].symbol = '@';
            this.biomeTypes[5].symbol = '%';
            this.biomeTypes[6].symbol = '-';
            this.biomeTypes[7].symbol = '+';
        }
    }
}