content: /*
   * Copyright 2021-2022 Alibaba Group Holding Ltd.
   *
   *    Licensed under the Apache License, Version 2.0 (the "License");
   *    you may not use this file except in compliance with the License.
   *    You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   *    Unless required by applicable law or agreed to in writing, software
   *    distributed under the License is distributed on an "AS IS" BASIS,
   *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *    See the License for the specific language governing permissions and
   *    limitations under the License.
   */
  
  package com.aliyun.fastmodel.driver.server.websocket;
  
  import java.awt.*;
  import java.awt.image.BufferedImage;
  
  import javax.swing.*;
  
  import lombok.Setter;
  
  /**
   * Desc:
   *
   * @author panguanjing
   * @date 2021/2/9
   */
  @Setter
  public class ImagePanel extends JPanel {
      public static final int TILED = 0;
      public static final int SCALED = 1;
      public static final int ACTUAL = 2;
  
      private BufferedImage image;
      private int style;
      private float alignmentX = 0.5f;
      private float alignmentY = 0.5f;
  
      public ImagePanel(BufferedImage image) {
          this(image, ACTUAL);
      }
  
      public ImagePanel(BufferedImage image, int style) {
          this.image = image;
          this.style = style;
          setLayout(new BorderLayout());
      }
  
      public void setImageAlignmentX(float alignmentX) {
          this.alignmentX = alignmentX > 1.0f ? 1.0f : alignmentX < 0.0f ? 0.0f
              : alignmentX;
      }
  
      public void setImageAlignmentY(float alignmentY) {
          this.alignmentY = alignmentY > 1.0f ? 1.0f : alignmentY < 0.0f ? 0.0f
              : alignmentY;
  
      }
  
      public void add(JComponent component) {
          add(component, null);
      }
  
      public void add(JComponent component, Object constraints) {
          component.setOpaque(false);
  
          if (component instanceof JScrollPane) {
              JScrollPane scrollPane = (JScrollPane)component;
              JViewport viewport = scrollPane.getViewport();
              viewport.setOpaque(false);
              Component c = viewport.getView();
  
              if (c instanceof JComponent) {
                  ((JComponent)c).setOpaque(false);
              }
          }
  
          super.add(component, constraints);
      }
  
      @Override
      protected void paintComponent(Graphics g) {
          super.paintComponent(g);
  
          if (image == null) {return;}
  
          switch (style) {
              case TILED:
                  drawTiled(g);
                  break;
  
              case SCALED:
                  Dimension d = getSize();
                  g.drawImage(image, 0, 0, d.width, d.height, null);
                  break;
  
              case ACTUAL:
                  drawActual(g);
                  break;
              default:
                  break;
          }
      }
  
      private void drawTiled(Graphics g) {
          Dimension d = getSize();
          int width = image.getWidth(null);
          int height = image.getHeight(null);
  
          for (int x = 0; x < d.width; x += width) {
              for (int y = 0; y < d.height; y += height) {
                  g.drawImage(image, x, y, null, null);
              }
          }
      }
  
      private void drawActual(Graphics g) {
          Dimension d = getSize();
          float x = (d.width - image.getWidth()) * alignmentX;
          float y = (d.height - image.getHeight()) * alignmentY;
          g.drawImage(image, (int)x, (int)y, this);
      }
  }
  