import java.awt.*;
import javax.swing.*;

public class AlgoFrame extends JFrame{

    private int canvasWidth;
    private int canvasHeight;

    public AlgoFrame(String title, int canvasWidth, int canvasHeight){

        super(title);

        this.canvasWidth = canvasWidth;
        this.canvasHeight = canvasHeight;

        AlgoCanvas canvas = new AlgoCanvas();
        setContentPane(canvas);
        pack();

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);

        setVisible(true);
    }

    public AlgoFrame(String title){

        this(title, 1024, 768);
    }

    public int getCanvasWidth(){return canvasWidth;}
    public int getCanvasHeight(){return canvasHeight;}

    // data
    private HeapSortData data;
    public void render(HeapSortData data){
        this.data = data;
        repaint();
    }

    private class AlgoCanvas extends JPanel{

        public AlgoCanvas(){
            // 双缓存
            super(true);
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);

            Graphics2D g2d = (Graphics2D)g;

            // 抗锯齿
            RenderingHints hints = new RenderingHints(
                    RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_ON);
            hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
            g2d.addRenderingHints(hints);

            // 具体绘制
            int w = canvasWidth/data.N();
            for(int i = 0 ; i < data.N() ; i ++ ) {
                if ( i >= data.heapIndex)
                    AlgoVisHelper.setColor(g2d, AlgoVisHelper.Red);
                else
                    AlgoVisHelper.setColor(g2d, AlgoVisHelper.Grey);

                AlgoVisHelper.fillRectangle(g2d, i * w, canvasHeight - data.get(i), w - 1, data.get(i));
            }
        }

        @Override
        public Dimension getPreferredSize(){
            return new Dimension(canvasWidth, canvasHeight);
        }
    }
}

public class HeapSortData {

    private int[] numbers;
    public int heapIndex;   // numbers[heapIndex...N) 已经排好序

    public HeapSortData(int N, int randomBound){

        numbers = new int[N];
        heapIndex = N;

        for( int i = 0 ; i < N ; i ++)
            numbers[i] = (int)(Math.random()*randomBound) + 1;
    }

    public int N(){
        return numbers.length;
    }

    public int get(int index){
        if( index < 0 || index >= numbers.length)
            throw new IllegalArgumentException("Invalid index to access Sort Data.");

        return numbers[index];
    }

    public void swap(int i, int j) {

        if( i < 0 || i >= numbers.length || j < 0 || j >= numbers.length)
            throw new IllegalArgumentException("Invalid index to access Sort Data.");

        int t = numbers[i];
        numbers[i] = numbers[j];
        numbers[j] = t;
    }
}

import java.awt.*;

public class AlgoVisualizer {

    private static int DELAY = 10;

    private HeapSortData data;
    private AlgoFrame frame;

    public AlgoVisualizer(int sceneWidth, int sceneHeight, int N){

        // 初始化数据
        data = new HeapSortData(N, sceneHeight);

        // 初始化视图
        EventQueue.invokeLater(() -> {
            frame = new AlgoFrame("Heap Sort Visualization", sceneWidth, sceneHeight);

            new Thread(() -> {
                run();
            }).start();
        });
    }

    public void run(){

        setData(data.N());

        // 建堆
        for( int i = (data.N()-1-1)/2 ; i >= 0 ; i -- ){
            shiftDown(data.N(), i);
        }

        // 堆排序
        for( int i = data.N()-1; i > 0 ; i-- ){
            data.swap(0, i);
            shiftDown(i, 0);
            setData(i);
        }

        setData(0);
    }

    private void shiftDown(int n, int k){

        while( 2*k+1 < n ){
            int j = 2*k+1;
            if( j+1 < n && data.get(j+1) > data.get(j) )
                j += 1;

            if( data.get(k) >= data.get(j) )
                break;

            data.swap(k, j);
            setData(data.heapIndex);

            k = j;
        }
    }

    private void setData(int heapIndex){

        data.heapIndex = heapIndex;

        frame.render(data);
        AlgoVisHelper.pause(DELAY);
    }

    public static void main(String[] args) {

        int sceneWidth = 800;
        int sceneHeight = 800;
        int N = 100;

        AlgoVisualizer vis = new AlgoVisualizer(sceneWidth, sceneHeight, N);
    }
}

import java.awt.*;
import java.awt.geom.Ellipse2D;

import java.awt.geom.Rectangle2D;
import java.lang.InterruptedException;

public class AlgoVisHelper {

    private AlgoVisHelper(){}

    public static final Color Red = new Color(0xF44336);
    public static final Color Pink = new Color(0xE91E63);
    public static final Color Purple = new Color(0x9C27B0);
    public static final Color DeepPurple = new Color(0x673AB7);
    public static final Color Indigo = new Color(0x3F51B5);
    public static final Color Blue = new Color(0x2196F3);
    public static final Color LightBlue = new Color(0x03A9F4);
    public static final Color Cyan = new Color(0x00BCD4);
    public static final Color Teal = new Color(0x009688);
    public static final Color Green = new Color(0x4CAF50);
    public static final Color LightGreen = new Color(0x8BC34A);
    public static final Color Lime = new Color(0xCDDC39);
    public static final Color Yellow = new Color(0xFFEB3B);
    public static final Color Amber = new Color(0xFFC107);
    public static final Color Orange = new Color(0xFF9800);
    public static final Color DeepOrange = new Color(0xFF5722);
    public static final Color Brown = new Color(0x795548);
    public static final Color Grey = new Color(0x9E9E9E);
    public static final Color BlueGrey = new Color(0x607D8B);
    public static final Color Black = new Color(0x000000);
    public static final Color White = new Color(0xFFFFFF);

    public static void strokeCircle(Graphics2D g, int x, int y, int r){

        Ellipse2D circle = new Ellipse2D.Double(x-r, y-r, 2*r, 2*r);
        g.draw(circle);
    }

    public static void fillCircle(Graphics2D g, int x, int y, int r){

        Ellipse2D circle = new Ellipse2D.Double(x-r, y-r, 2*r, 2*r);
        g.fill(circle);
    }

    public static void strokeRectangle(Graphics2D g, int x, int y, int w, int h){

        Rectangle2D rectangle = new Rectangle2D.Double(x, y, w, h);
        g.draw(rectangle);
    }

    public static void fillRectangle(Graphics2D g, int x, int y, int w, int h){

        Rectangle2D rectangle = new Rectangle2D.Double(x, y, w, h);
        g.fill(rectangle);
    }

    public static void setColor(Graphics2D g, Color color){
        g.setColor(color);
    }

    public static void setStrokeWidth(Graphics2D g, int w){
        int strokeWidth = w;
        g.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
    }

    public static void pause(int t) {
        try {
            Thread.sleep(t);
        }
        catch (InterruptedException e) {
            System.out.println("Error sleeping");
        }
    }

}