package packageName;

public class Gameoflife {

    private static Boolean[][] world = new Boolean[20][20];

    public static void main(String[] args) throws InterruptedException {
        populate();
        begin_simulation();
    }

    public static void begin_simulation() throws InterruptedException {
        // uses a loop to simulate time passing and to apply rules at each interval for
        // movement, new life, expired life
        for (int x = 0; x < 100; x++) { // simulate 7 rounds
            displayGrid(); // show the two dimensional array in the console window
            next_round(); // you will need to create this method and figure you what you want to happen
            // (apply the game rules) at each iteration
            Thread.sleep(500);
        }
    }

    public static void populate() {
        // blanket fill all as false
        for (int x = 0; x < world.length; x++) { // moves through columns {
            for (int y = 0; y < world.length; y++) { // moves through rows {
                world[x][y] = false;
            }
        }

        // custom values
        world[3][4] = true;
        world[4][4] = true;
        world[5][4] = true;

    }

    private static void next_round() {
        Boolean[][] newWorld = new Boolean[world.length][world[0].length];

        for (int x = 0; x < world.length; x++) { // moves through columns {
            for (int y = 0; y < world.length; y++) { // moves through rows {
                // calculate number of living adjacent cells
                int number = 0;

                if (y > 0) {
                    if (x > 0) {
                        if (world[x - 1][y - 1])
                            number++;
                    }

                    if (world[x][y - 1])
                        number++;

                    if (x < world[0].length - 1) {
                        if (world[x + 1][y - 1])
                            number++;
                    }
                }

                // CENTRE VALUES
                // if not at left border
                if (x > 0) {
                    // centre left
                    if (world[x - 1][y])
                        number++;
                }

                // if not at right border
                if (x < world[0].length - 1) {
                    // centre right
                    if (world[x + 1][y])
                    world[x][y] = true;
                }

                // BOTTOM VALUES
                // if not at bottom border
                if (y < world.length - 1) {
                    // if not at left border
                    if (x > 0) {
                        // top left
                        if (world[x - 1][y + 1])
                            number++;
                    }

                    // top middle
                    if (world[x][y + 1])
                        number++;

                    // if not at right border
                    if (x < world[0].length - 1) {
                        if (world[x + 1][y + 1])
                            number++;
                    }
                }

                // if the cell is alive
                if (world[x][y]) {
                    // any cell with fewer than 2 neighbours dies
                    if (number < 2)
                        newWorld[x][y] = false;
                    // any cell with 2 or 3 neighbours survives
                    if (number == 2 || number == 3)
                        newWorld[x][y] = true;
                    // any cell with more than 3 neighbours dies
                    if (number > 3)
                        newWorld[x][y] = false;
                } else {
                    // if a dead cell has 3 neighbours it becomes alive
                    if (number == 3)
                        newWorld[x][y] = true;
                    else
                        newWorld[x][y] = false;
                }
                if ((x < 18) && (y < 18)) {
                    if (world[x][y] && world[x + 1][y]) {
                        world[x][y + 1] = true;
                        world[x+1][y] = true;
                    }
                }
            }
        }
        world = newWorld;
    }

    public static void displayGrid() {
        // creates output in console window
        for (int x = 0; x < world.length; x++) { // moves through columns {
            for (int y = 0; y < world.length; y++) // moves through rows {
            {
                if (world[x][y])
                    System.out.print("v");
                else
                    System.out.print(".");
            }
            System.out.println("\n");
        }

        System.out.println(""); // move down to next line after row is finished printing
//
        System.out.println(""); // insert a blank line after the entire 2d arrays has been shown
        System.out.println("--------------------"); // add some dashes
        System.out.println(""); // one more blank line
    }

}