package com.jnumerical.gameoflife;

import java.awt.Color;
import java.awt.Graphics;
import java.util.Random;

public class Board
{
    private int cellPix, gridWidth, gridHeight, gap, shift, chance, boardLifetime, colorLifetime, steps;
    private int[][] grid = new int[gridWidth][gridHeight];
    private int[][] gridNext = new int[gridWidth][gridHeight];
    private Color colorBG, colorA, colorB, colorC, colorD;
    private Random rand = new Random();
    
    public Board(int c, int cPix, int g, int bLife, int cLife) {
        steps = 0;
        chance = c;
        cellPix = cPix;
        boardLifetime = bLife;
        colorLifetime = cLife;
        gridWidth = Main.width / cellPix;
        gridHeight = Main.height / cellPix;
        grid = new int[gridWidth][gridHeight];
        gridNext = new int[gridWidth][gridHeight];
        gap = g;
        shift = gap / 2;
    }
    
    public void update(){
        calculateNext();
        setNext();
        chooseColors();
        
        if(steps % colorLifetime == 0) createColors();
        if(steps % boardLifetime == 0) randomizeGrid();
        steps++;
    }
    
    public void createColors(){
        colorBG = new Color(0, 0, 0);
        
        int r = 0, g = 0, b = 0;
        int rand6 = rand.nextInt(6);
        int rand256 = rand.nextInt(256);
        if(rand6 == 0){
            r = 0;
            g = rand256;
            b = 255;
        }
        else if(rand6 == 1){
            r = 255;
            g = rand256;
            b = 0;
        }
        else if(rand6 == 2){
            r = rand256;
            g = 255;
            b = 0;
        }
        else if(rand6 == 3){
            r = rand256;
            g = 0;
            b = 255;
        }
        else if(rand6 == 4){
            r = 255;
            g = 0;
            b = rand256;
        }
        else if(rand6 == 5){
            r = 0;
            g = 255;
            b = rand256;
        }
        
        colorA = new Color((r+g)/2, (g+b)/2, (b+r)/2);
        colorB = new Color(r, g, b);        
        colorC = new Color((r+b)/2, (g+r)/2, (b+g)/2);
        colorD = new Color((r+b)/4, (g+r)/4, (b+g)/4);
    }
    
    public void calculateNext(){
        int neighbors;
        for(int i=0; i<gridWidth; i++)
            for(int j=0; j<gridHeight; j++){
                neighbors = getNeighbors(i,j);
                if(neighbors==3 || (neighbors==2 && grid[i][j]>0)) gridNext[i][j] = 1;
                else gridNext[i][j] = 0;
            }
    }
    
    public int getNeighbors(int i, int j){
        int num = 0;
        i += gridWidth;
        j += gridHeight;
        if(grid[(i+1) % gridWidth][j     % gridHeight] > 0) num++;
        if(grid[(i-1) % gridWidth][j     % gridHeight] > 0) num++;
        if(grid[i     % gridWidth][(j+1) % gridHeight] > 0) num++;
        if(grid[i     % gridWidth][(j-1) % gridHeight] > 0) num++;
        if(grid[(i+1) % gridWidth][(j+1) % gridHeight] > 0) num++;
        if(grid[(i-1) % gridWidth][(j-1) % gridHeight] > 0) num++;
        if(grid[(i+1) % gridWidth][(j-1) % gridHeight] > 0) num++;
        if(grid[(i-1) % gridWidth][(j+1) % gridHeight] > 0) num++;
        return num;
    }
    
    public void setNext(){
        for(int i=0; i<gridWidth; i++)
            for(int j=0; j<gridHeight; j++){
                grid[i][j] = gridNext[i][j];
            }
    }
    
    public void render(Graphics g){
        g.setColor(colorBG);
        g.fillRect(0, 0, Main.width, Main.height);
        for(int i=0; i<gridWidth; i++){
            for(int j=0; j<gridHeight; j++){
                if(grid[i][j] != 0){
                    if(grid[i][j] == 1) g.setColor(colorD);
                    else if(grid[i][j] == 2) g.setColor(colorC);
                    else if(grid[i][j] == 3) g.setColor(colorB);
                    else g.setColor(colorA);
                    g.fillRect(i*cellPix +shift, j*cellPix +shift, cellPix-gap, cellPix-gap);
                } 
            }
        }
    }
    
    private void randomizeGrid(){
        for(int i=0; i<gridWidth; i++)
            for(int j=0; j<gridHeight; j++){
                if(rand.nextInt(100) < chance) grid[i][j] = 1;
                else grid[i][j] = 0;
            }
    }
    
    public void chooseColors(){
        for(int i=0; i<gridWidth; i++)
            for(int j=0; j<gridHeight; j++){
                if(grid[i][j] > 0) grid[i][j] = getNeighbors(i,j);
            }
    }
}