/*******************************************************************************
    * Copyhacked (H) 2012-2025.
    * This program and the accompanying materials
    * are made available under no term at all, use it like
    * you want, but share and discuss it
    * every time possible with every body.
    * 
    * Contributors:
    *      ron190 at ymail dot com - initial implementation
   ******************************************************************************/
  package com.jsql.view.swing.terminal;
  
  import com.jsql.util.LogLevelUtil;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  
  import javax.swing.text.BadLocationException;
  import javax.swing.text.DefaultCaret;
  import javax.swing.text.JTextComponent;
  import java.awt.*;
  
  /**
   * A caret in a block shape.
   */
  public class BlockCaret extends DefaultCaret {
      
      /**
       * Log4j logger sent to view.
       */
      private static final Logger LOGGER = LogManager.getRootLogger();
      
      /**
       * Create a caret shaped for terminal.
       */
      public BlockCaret() {
          this.setBlinkRate(500);  // half a second
      }
  
      @Override
      protected synchronized void damage(Rectangle r) {
          if (r == null) {
              return;
          }
  
          // give values to x,y,width,height (inherited from java.awt.Rectangle)
          this.x = r.x;
          this.y = r.y;
          this.height = r.height;
          
          // A value for width was probably set by paint(), which we leave alone.
          // But the first call to damage() precedes the first call to paint(), so
          // in this case we must be prepared to set a valid width, or else
          // paint()
          // will receive a bogus clip area and caret will not get drawn properly.
          if (this.width <= 0) {
              this.width = this.getComponent().getWidth();
          }
  
          //Calls getComponent().repaint(x, y, width, height) to erase
          this.repaint();
          
          // previous location of caret. Sometimes one call isn't enough.
          this.repaint();
      }
  
      @Override
      public void paint(Graphics g) {
          JTextComponent comp = this.getComponent();
          if (comp == null) {
              return;
          }
  
          int dot = this.getDot();
          Rectangle r = null;
          char dotChar;
          
          try {
              if (comp.modelToView2D(dot) != null) {
                  r = comp.modelToView2D(dot).getBounds();
              }
              dotChar = comp.getText(dot, 1).charAt(0);
          } catch (BadLocationException e) {
              LOGGER.log(LogLevelUtil.CONSOLE_JAVA, e, e);
              return;
          }
  
          if (r == null) {
              return;
          }
          if (Character.isWhitespace(dotChar)) {
              dotChar = '_';
          }
          if (this.x != r.x || this.y != r.y) {
              // paint() has been called directly, without a previous call to
              // damage(), so do some cleanup. (This happens, for example, when
              // the text component is resized.)
              this.damage(r);
              return;
          }
 
         g.setColor(new Color(0, 255, 0));
         g.setXORMode(comp.getBackground()); // do this to draw in XOR mode
 
         this.width = g.getFontMetrics().charWidth(dotChar);
         if (this.isVisible()) {
             g.fillRect(r.x, r.y, this.width, r.height);
         }
     }
 }