package jalview.util;

import java.awt.Toolkit;
import java.awt.event.MouseEvent;

/**
 * retrieve KeyEvent masks for Java 8 or Java 11+
 * 
 * @author hansonr
 *
 */
public class ShortcutKeyMaskExWrapper
{
  public static final int SHIFT_DOWN_MASK;

  public static final int ALT_DOWN_MASK;

  public static final int SHORTCUT_MASK;

  static
  {
    float specversion = Platform.getJavaVersion();
    String method;
    // BH technically, these are not masks; they are bits.
    if (specversion >= 11)
    {
      SHIFT_DOWN_MASK = 0x040; // KeyEvent.SHIFT_DOWN_MASK;
      ALT_DOWN_MASK = 0x200; // KeyEvent.ALT_DOWN_MASK;
      method = "getMenuShortcutKeyMaskEx";
    }
    else
    {
      SHIFT_DOWN_MASK = 0x01; // KeyEvent.SHIFT_MASK;
      ALT_DOWN_MASK = 0x08; // KeyEvent.ALT_MASK;
      method = "getMenuShortcutKeyMask";
    }

    int mask = 0;
    try
    {
      // Just use reflection -- doesn't matter what version is running.
      Toolkit tk = Toolkit.getDefaultToolkit();
      mask = (int) (tk.getClass().getMethod(method, new Class<?>[0])
              .invoke(tk, new Object[0]));
    } catch (Exception e)
    {
      System.out.println("Shortcut exception: " + e);
    }

    SHORTCUT_MASK = mask;
  }

  // BH Q: Why not just use the public static field?
  public static int getMenuShortcutKeyMaskEx()
  {
    return SHORTCUT_MASK;
  }

  // BH Q: Why is this here?
  public static int getModifiersEx(MouseEvent e)
  {
    return e.getModifiersEx();
  }

}