import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.geometry.Rectangle2D;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Alert.AlertType;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import java.util.Random;
  
public class myJigsaw extends Application {
  public int m;     //m是不在随机数组的那个数字
  ImageView[] imageViews = new ImageView[9];
  public static void main(String[] args) {
    Application.launch(args);
  }
  
  
  @Override
  public void start(Stage arg0) throws Exception {
    init(arg0);
  }
  public void init(Stage stage) {
    int[] n = random();       //自定义的函数，产生逆序数为偶数的不重复数组
  
    Image image = new Image("1.png");
  
  
    GridPane gridPane = new GridPane();
  
    for(int i = 0, k = 0; i <= 2; ++i) {
      for(int j = 0; j <= 2; ++j, ++k) {
        imageViews[k] = new ImageView(image);    //初始化数组
        imageViews[k].setOnMouseClicked(new myevent());   //设置点击事件
        imageViews[k].setViewport(new Rectangle2D(100 * j, 100 * i, 100, 100));       //切割图片
      }
    }
  
    gridPane.add(imageViews[n[0]], 0, 0);             //按照产生的随机数将imageView数组加入面板
    gridPane.add(imageViews[n[1]], 1, 0);
    gridPane.add(imageViews[n[2]], 2, 0);
    gridPane.add(imageViews[n[3]], 0, 1);
    gridPane.add(imageViews[n[4]], 1, 1);
    gridPane.add(imageViews[n[5]], 2, 1);
    gridPane.add(imageViews[n[6]], 0, 2);
    gridPane.add(imageViews[n[7]], 1, 2);
    m = findnum(n);                         //找出那个不在随机数组里面的数字
    ImageView incomp = new ImageView(imageViews[m].getImage());       //用于显示空格子的图片
    ImageView comp = new ImageView(image);                   //用于显示完整的大图
    incomp.setViewport(imageViews[m].getViewport());
    Image image2 = new Image("2.png");                 //2.png为一个透明图，放在空格子中
    imageViews[m].setImage(image2);
    gridPane.add(imageViews[m], 2, 2);
    gridPane.setGridLinesVisible(true);
    BorderPane borderPane = new BorderPane(gridPane);
    VBox right = new VBox(20, incomp, comp);
    borderPane.setRight(right);
    Scene scene = new Scene(borderPane, 820, 420);
    stage.setScene(scene);
    stage.setResizable(false);
    stage.show();
  
  }
  
  public int[] random() {       //生成8个不重复的逆序数为偶数的数字
    int[] ran = new int[8];
    while(iso(ran) == false) {
      ran = random_num();
    }
    return ran;
  
  }
  
  public int[] random_num() {   //生成8个不重复数
    int r[] = new int[8];
    Random random = new Random();
    for(int i = 0; i < 8; ++i) {
      r[i] = random.nextInt(9);
      for(int j = 0;j < i; ++j) {
        while(r[i] == r[j]) {
          i--;
          break;
        }
      }
    }
    return r;
  }
  
  public boolean iso(int[] num) {     //判断逆序数是否为偶数
    int sum = 0;
    for(int i = 0; i <= 6; ++i) {
      for(int j = i; j <= 7; j++) {
        if(num[i] > num[j]) {
          sum++;
        }
      }
    }
    if((sum % 2) == 0 && sum != 0) {
      return true;
    }
  
    return false;
  
  }
  
  class myevent implements EventHandler<MouseEvent> {        //点击事件的实现
  
  
  @Override
    public void handle(MouseEvent arg0) {
    // TODO Auto-generated method stub
      ImageView img = (ImageView) arg0.getSource();
      double sx = img.getLayoutX();
      double sy = img.getLayoutY();
      double dispx = sx - imageViews[m].getLayoutX();
      double dispy = sy - imageViews[m].getLayoutY();
      if((dispx == -100) && (dispy == 0 )) {        //点击的空格左边的格子
        swapimg(img, imageViews[m]);       //交换imageView
        if(issucc(imageViews)) {             //判断是否拼成功
          Alert alert = new Alert(AlertType.WARNING, "成功！");
          alert.show();
        }
      }
  
      else if ((dispx == 0) && (dispy == -100)) {    //上面的格子
        swapimg(img, imageViews[m]);
        if(issucc(imageViews)) {
          Alert alert = new Alert(AlertType.WARNING, "成功！");
          alert.show();
        }
      }
      else if((dispx == 100) && (dispy == 0)) {        //右边的格子
        swapimg(img, imageViews[m]);
        if(issucc(imageViews)) {
          Alert alert = new Alert(AlertType.WARNING, "成功！");
          alert.show();
        }
      }
      else if((dispx == 0) && (dispy == 100)) {        //下面的格子
        swapimg(img, imageViews[m]);
        if(issucc(imageViews)) {
          Alert alert = new Alert(AlertType.WARNING, "成功！");
          alert.show();
        }
      }
    }
    public void swapimg(ImageView i1, ImageView i2) {       //交换两个imageView的实现
      int row1 = GridPane.getRowIndex(i1);
      int colu1 = GridPane.getColumnIndex(i1);
      int row2 = GridPane.getRowIndex(i2);
      int colu2 = GridPane.getColumnIndex(i2);
  
      GridPane.setRowIndex(i1, row2);
      GridPane.setColumnIndex(i1, colu2);
      GridPane.setRowIndex(i2, row1);
      GridPane.setColumnIndex(i2, colu1);
    }
  }
  public boolean issucc(ImageView[] imageViews) {                //判断是否拼成功
    for(int i = 0; i <= 8; ++i) {
      if(i != 3 * GridPane.getRowIndex(imageViews[i]) + GridPane.getColumnIndex(imageViews[i])) {
        return false;
      }
    }
      return true;
  }
  
  public int findnum(int[] n) {                       //找出m
    for(int j = 0; j <= 8; ++j) {
      if((j == n[0]) || (j == n[1]) || (j == n[2]) || (j == n[3]) || (j == n[4]) || (j == n[5]) || (j == n[6]) || (j == n[7])) {
      }
      else {
        return j;
      }
    }
    return -1;
  } 
  
}