import java.util.*;

public class SnakeModel {
	
	public  snakeUse getSnakeHead(){
		return(snakeUse)(snake.getLast());
	}
	
	public snakeUse getSnakeTail(){
		return (snakeUse)(snake.getFirst());
	}
	public snakeUse getRuningDiriction(){
		return runingDiriction;
	}
	public LinkedList getSnake(){
		return snake;
	}
	
	public LinkedList getOthers(){
		return others;
	}	
	public int getScore(){
		return gameScore;
	}
	public boolean getReadyAddScore(){
		return readyAddScore;
	}
	private void setSnakeHead(snakeUse snakeHead){
		this.snakeHead=snakeHead;
	}

	public snakeUse getTempBlock(){
		return tempBlock;
	}	
	private void setTempBlock(){
		tempBlock=(snakeUse)(others.get((int)(Math.random()*others.size())));
	}
	private void moveTo(Object a,LinkedList from,LinkedList to){
		from.remove(a);
		to.add(a);
	}
	
	public void initializeV(){
		others.clear();
		snake.clear();
		gameScore=0;
	 	for(int i=0;i<row;i++){
	 		for(int j=0;j<col;j++){	 			
	 			others.add(jps[i][j]);
	 		}
	 	}
	 	
	 	//初始化蛇的形狀([5][5]、[5][6]、[5][7])
	 	for(int i=5;i<8;i++){
	 		moveTo(jps[5][i],others,snake);
	 		
	 	}
	 	snakeHead=new snakeUse(5,7);

	 	
	 	//設置隨機塊
	 	tempBlock=new snakeUse(0,0);
	 	setTempBlock();
	 	//初始化運動方向
	 	runingDiriction=new snakeUse(1,0);
	 			
	}
	public SnakeModel(int row1,int col1){
	 	row=row1;
	 	col=col1;
	 	jps=new snakeUse[row][col];
	 	snake=new LinkedList();
	 	others=new LinkedList();
	 	
	 	for(int i=0;i<row;i++){
	 		for(int j=0;j<col;j++){
	 			jps[i][j]=new snakeUse(i,j);
	 			
	 		}
	 	}
	 		 	
	 	initializeV();

	 	
	 }
	
	//如果move成功返回true,否則(結束)，返回false
	//參數direction是snakeUse類型，
	//direction 的值:(0,1)表示向右(0,-1)表示向左
	//(1,0)表示向下(-1,0)表示向上
	
	public boolean move(snakeUse direction){
		//判斷給的方向是不是跟運行方向相反
		if (direction.reverse(runingDiriction)){
			snakeHead.setX(snakeHead.getX()+runingDiriction.getX());
			snakeHead.setY(snakeHead.getY()+runingDiriction.getY());			
		}else{
			snakeHead.setX(snakeHead.getX()+direction.getX());
			snakeHead.setY(snakeHead.getY()+direction.getY());			
		}

		
		//如果蛇吃了隨機塊
		try{
		if ((snakeHead.getX()==tempBlock.getX())
			&&(snakeHead.getY()==tempBlock.getY()))
			{
			moveTo(jps[snakeHead.getX()][snakeHead.getY()],others,snake);
			setTempBlock();
			
			gameScore+=1;
			readyAddScore=true;
				
			}else{
				readyAddScore=false;
				//是否出界
				if((snakeHead.getX()<row)&&(snakeHead.getY()<col)){
					//如果不出界，判斷是否與自身相交
					if(snake.contains(jps[snakeHead.getX()][snakeHead.getY()])){
						//如果相交,游戲結束
						return false;
					}else{
						//如果不相交，就把snakeHead加到snake里面，并且把尾巴移出
						moveTo(jps[snakeHead.getX()][snakeHead.getY()],others,snake);
						moveTo(snake.getFirst(),snake,others);
					}
					
				}else{
					//出界！游戲結束
					return false;
				}				
			}
		
		
		
			
			
			
		}catch(ArrayIndexOutOfBoundsException e){
			return false;
		}
			//更新運行方向
		if (!(direction.reverse(runingDiriction)
		||direction.equals(runingDiriction))){
				runingDiriction.setX(direction.getX());
				runingDiriction.setY(direction.getY());
			}
		
		return true;
	}
	
	private int row,col;
	private snakeUse snakeHead;
	private snakeUse[][] jps;
	private LinkedList snake;
	private LinkedList others;
	private snakeUse tempBlock;
	private snakeUse runingDiriction;
	private int gameScore=0;
	private boolean readyAddScore=false;
}