Board.java

public class Board {
    private int _maxNum;
    private int _num0s;
    private int _score;
    private Block[][] _board;

    public Board() {
	_maxNum = 0;
	_num0s = 16;
	_score = 0;
	_board = new Block[4][4];
	for (int i = 0; i < 4; i++) {
	    for (int i2 = 0; i2 < 4; i2++) {
		_board[i][i2] = new Block();
	    }
	}
    }

    public void addBlock() {
	int pos = (int)(Math.random() * _num0s); //Selects a position from empty blocks
	int index = 0; //Current index
	if (_num0s == 0) {return;} //Does nothing if there are no empty spaces
	for (int r = 0; r < 4; r++) {
	    for (int c = 0; c < 4; c++) {
		if(_board[r][c].isEmpty()){
		    if (index == pos) { //If the index matches the position, set the block value to 2 or 4
			_board[r][c].set(((int)(Math.random()*2)+1)*2);
			_num0s--; //Decreases number of empty spaces by one
			return;
		    }
		    index++;
		}
	    }
	}
    }

    public int slideLeftRow(int r){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=0;i<3;i++){
		if (_board[r][i].isEmpty()){
		    if(!_board[r][i+1].isEmpty()){ //Does nothing for two empty blocks
			_board[r][i].set(_board[r][i+1].get());
			_board[r][i+1].set(0);
			moves++;
		    }
		}
	    }
	}
	return moves; //Keeps track of actions
    }
    public int mergeLeft(int r){
	int merges=0;
	for(int i=0;i<3;i++){
	    if((_board[r][i].get()==_board[r][i+1].get())&&!_board[r][i].isEmpty()){ //Ignores zeroes
		_board[r][i].set(_board[r][i].get()*2); //Double value of block
		if(_board[r][i].get()>_maxNum){
		    _maxNum=_board[r][i].get(); //Set _maxNum if this block value is the greatest
		}
		_score+=_board[r][i].get(); //Add to score
		_board[r][i+1].set(0); //Delete previous block
		_num0s++;
		slideLeftRow(r); //Slides again to make up for open blocks due to merge
		merges++;
	    }
	}
	return merges; //Keeps track of merges
    }
    public void slideLeft(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideLeftRow(i);
	    merges+=mergeLeft(i);
	}
	if(moves+merges>0){ //Only if an action is made
	    addBlock();
	}
    }
    public int slideRightRow(int r){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=3;i>0;i--){
		if (_board[r][i].isEmpty()){
		    if(!_board[r][i-1].isEmpty()){
			_board[r][i].set(_board[r][i-1].get());
			_board[r][i-1].set(0);
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeRight(int r){
	int merges=0;
	for(int i=3;i>0;i--){
	    if((_board[r][i].get()==_board[r][i-1].get())&&!_board[r][i].isEmpty()){
		_board[r][i].set(_board[r][i].get()*2);
		if(_board[r][i].get()>_maxNum){
		    _maxNum=_board[r][i].get();
		}
		_score+=_board[r][i].get();
		_board[r][i-1].set(0);
		_num0s++;
		slideRightRow(r);
		merges++;
	    }
	}
	return merges;
    }
    public void slideRight(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideRightRow(i);
	    merges+=mergeRight(i);
	}
	if(moves+merges>0){
	    addBlock();
	}
    }
    public int slideUpCol(int c){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=0;i<3;i++){
		if (_board[i][c].isEmpty()){
		    if(!_board[i+1][c].isEmpty()){
			_board[i][c].set(_board[i+1][c].get());
			_board[i+1][c].set(0);
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeUp(int c){
	int merges=0;
	for(int i=0;i<3;i++){
	    if((_board[i][c].get()==_board[i+1][c].get())&&!_board[i][c].isEmpty()){
		_board[i][c].set(_board[i][c].get()*2);
		if(_board[i][c].get()>_maxNum){
		    _maxNum=_board[i][c].get();
		}
		_score+=_board[i][c].get();
		_board[i+1][c].set(0);
		_num0s++;
		slideUpCol(c);
		merges++;
	    }
	}
	return merges;
    }
    public void slideUp(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideUpCol(i);
	    merges+=mergeUp(i);
	}
	if(moves+merges>0){
	    addBlock();
	}
    }
    public int slideDownCol(int c){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=3;i>0;i--){
		if (_board[i][c].isEmpty()){
		    if(!_board[i-1][c].isEmpty()){
			_board[i][c].set(_board[i-1][c].get());
			_board[i-1][c].set(0);
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeDown(int c){
	int merges=0;
	for(int i=3;i>0;i--){
	    if((_board[i][c].get()==_board[i-1][c].get())&&!_board[i][c].isEmpty()){
		_board[i][c].set(_board[i][c].get()*2);
		if(_board[i][c].get()>_maxNum){
		    _maxNum=_board[i][c].get();
		}
		_score+=_board[i][c].get();
		_board[i-1][c].set(0);
		_num0s++;
		slideDownCol(c);
		merges++;
	    }
	}
	return merges;
    }
    public void slideDown(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideDownCol(i);
	    merges+=mergeDown(i);
	}
	if(moves+merges>0){
	    addBlock();
	}
    }

    public int slideLeftRowTest(int r){ //Tests to see if an action would be made for gameStatus()
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=0;i<3;i++){
		if (_board[r][i].isEmpty()){
		    if(!_board[r][i+1].isEmpty()){
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeLeftTest(int r){ //Tests to see if an action would be made for gameStatus()
	int merges=0;
	for(int i=0;i<3;i++){
	    if((_board[r][i].get()==_board[r][i+1].get())&&!_board[r][i].isEmpty()){
      		merges++;
	    }
	}
	return merges;
    }
    public int slideLeftTest(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideLeftRowTest(i);
	    merges+=mergeLeftTest(i);
	}
	return moves+merges;
    }
    public int slideRightRowTest(int r){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=3;i>0;i--){
		if (_board[r][i].isEmpty()){
		    if(!_board[r][i-1].isEmpty()){
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeRightTest(int r){
	int merges=0;
	for(int i=3;i>0;i--){
	    if((_board[r][i].get()==_board[r][i-1].get())&&!_board[r][i].isEmpty()){
		merges++;
	    }
	}
	return merges;
    }
    public int slideRightTest(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideRightRowTest(i);
	    merges+=mergeRightTest(i);
	}
	return moves+merges;
    }
    public int slideUpColTest(int c){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=0;i<3;i++){
		if (_board[i][c].isEmpty()){
		    if(!_board[i+1][c].isEmpty()){
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeUpTest(int c){
	int merges=0;
	for(int i=0;i<3;i++){
	    if((_board[i][c].get()==_board[i+1][c].get())&&!_board[i][c].isEmpty()){
		merges++;
	    }
	}
	return merges;
    }
    public int slideUpTest(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideUpColTest(i);
	    merges+=mergeUpTest(i);
	}
        return moves+merges;
    }
    public int slideDownColTest(int c){
	int moves=0;
	for(int p=1; p<4; p++){
	    for(int i=3;i>0;i--){
		if (_board[i][c].isEmpty()){
		    if(!_board[i-1][c].isEmpty()){
			moves++;
		    }
		}
	    }
	}
	return moves;
    }
    public int mergeDownTest(int c){
	int merges=0;
	for(int i=3;i>0;i--){
	    if((_board[i][c].get()==_board[i-1][c].get())&&!_board[i][c].isEmpty()){
		merges++;
	    }
	}
	return merges;
    }
    public int slideDownTest(){
	int moves=0;
	int merges=0;
	for(int i=0;i<4;i++){
	    moves+=slideDownColTest(i);
	    merges+=mergeDownTest(i);
	}
	return moves+merges;
    }
    public String gameStatus() {
	if (_maxNum >= 2048) {return "Win";} //You win if you have a block with a value of 2048 or higher
	if (slideRightTest()+slideLeftTest()+slideUpTest()+slideDownTest()>0) {return "Ongoing";} //If an action is possible in any direction, the game is ongoing
	return "Loss";
    }
    public int getScore() { return _score; }
    public String toString(){
	String foo = "----------------------\n";
	for( int i =0; i < 4; i++ ) {
	    foo += "| ";
	    for( int j=0; j < 4; j++ ) {
		foo +=_board[i][j] + "|"; //get(i+1,j+1)
	    }
	    foo += "\n----------------------\n";
	}

	return foo;
    }
}