package bufferedterrain;

import org.newdawn.slick.AppGameContainer;
import org.newdawn.slick.BasicGame;
import org.newdawn.slick.Color;
import org.newdawn.slick.GameContainer;
import org.newdawn.slick.Graphics;
import org.newdawn.slick.Input;
import org.newdawn.slick.SlickException;

public class Main extends BasicGame {

    Main()
    {
        super("Terrain Test");
    }

    private Input input;
    
    private int[][] terrain;
    
    public MersenneTwisterFast mt;

    private int width = 256;
    private int height = 192;

    public static void main(String[] args) {
        try
        {
            AppGameContainer app = new AppGameContainer(new Main());
            app.setDisplayMode(1024, 768, false);
            app.setFullscreen(false);
            app.setShowFPS(false);
            app.setVSync(true);
            app.setClearEachFrame(false);
            app.start();
        }
        catch (SlickException e)
        {
            e.printStackTrace();
        }
    }

    @Override
    public void init(GameContainer container) throws SlickException
    {
        input = container.getInput();
        mt = new MersenneTwisterFast();
        start();
    }

    @Override
    public void update(GameContainer container, int delta) throws SlickException
    {
        if (input.isKeyPressed(Input.KEY_ESCAPE)) container.exit();
        if (input.isKeyPressed(Input.KEY_F2)) start();
        if (input.isMouseButtonDown(Input.MOUSE_LEFT_BUTTON))
        {
            int mX = (int) Math.floor(input.getMouseX() / 4);
            int mY = (int) Math.floor(input.getMouseY() / 4);
            if (mX >= 1 && mX < width - 1 && mY >= 1 && mY < height - 1)
            {
                terrain[mX][mY] = -1;
                terrain[mX + 1][mY] = -1;
                terrain[mX + 1][mY + 1] = -1;
                terrain[mX][mY + 1] = -1;
            }
        }
        if (input.isMouseButtonDown(Input.MOUSE_RIGHT_BUTTON))
        {
            int mX = (int) Math.floor(input.getMouseX() / 4);
            int mY = (int) Math.floor(input.getMouseY() / 4);
            if (mX >= 1 && mX < width - 1 && mY >= 1 && mY < height - 1)
            {
                terrain[mX][mY] = 0;
                terrain[mX + 1][mY] = 0;
                terrain[mX + 1][mY + 1] = 0;
                terrain[mX][mY + 1] = 0;
            }
        }
        for (int x = 0; x < width; x++)
        {
            for (int y = height - 2; y >= 0; y--)
            {
                if (terrain[x][y] > 0)
                {
                    if (terrain[x][y+1] == 0)
                    {
                        terrain[x][y+1] = terrain[x][y];
                        terrain[x][y] = 0;
                    }
                }
                if (mt.nextBoolean())
                {
                    if (x + 1 < width)
                    {
                        if (terrain[x+1][y] == 0 && terrain[x][y] > 0)
                        {
                            terrain[x+1][y] = terrain[x][y];
                            terrain[x][y] = 0;
                        }
                    }
                    if (x - 1 >= 0)
                    {
                        if (terrain[x-1][y] == 0 && terrain[x][y] > 0)
                        {
                            terrain[x-1][y] = terrain[x][y];
                            terrain[x][y] = 0;
                        }
                    }
                }
            }
        }
        terrain[32 + mt.nextInt(32)-16][0] = 1;
        terrain[96 + mt.nextInt(32)-16][0] = 2;
        terrain[160 + mt.nextInt(32)-16][0] = 3;
        terrain[224 + mt.nextInt(32)-16][0] = 4;

    }

    public void render(GameContainer container, Graphics g) throws SlickException
    {
        g.setColor(Color.black);
        g.fillRect(0, 0, 1024, 768);
        for (int y = 0; y < height; y++)
        {
            for (int x = 0; x < width; x++)
            {
                if (terrain[x][y] != 0)
                {
                    switch(terrain[x][y])
                    {
                        case -1:
                        {
                            g.setColor(new Color(255, 100, 100));
                            break;
                        }
                        case 1:
                        {
                            g.setColor(Color.white);
                            break;
                        }
                        case 2:
                        {
                            g.setColor(Color.orange);
                            break;
                        }
                        case 3:
                        {
                            g.setColor(Color.blue);
                            break;
                        }
                        case 4:
                        {
                            g.setColor(Color.red);
                            break;
                        }
                    }
                    g.fillRect(x * 4, y * 4, 4, 4);
                }
            }
        }
    }

    private void start()
    {
        terrain = new int[width][height];
    }
}