import static org.assertj.core.api.Assertions.assertThat;

import org.eclipse.jface.dialogs.TitleAreaDialog;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.FileDialog;
import org.eclipse.swt.widgets.Shell;
import org.junit.jupiter.api.Test;


public class SWTRadioButtonFocusTest {

  private SimpleDialog _dialog;

  @Test
  /**
   * This is a user test - only opens the Dialog to test the behavior by self
   */
  void testRadioButtons() {
      Shell shell = new Shell();
      SimpleDialog dialog = new SimpleDialog(shell, true);
      dialog.open();
  }

  @Test
  void testRadioButtonsAuto() {
      Shell shell = new Shell();
      _dialog = new SimpleDialog(shell, false);
      _dialog.setBlockOnOpen(false);
      _dialog.open();

      _dialog.getRadioButton1().setSelection(false);
      _dialog.getRadioButton2().setSelection(true);
      _dialog.getRadioButton2().notifyListeners(SWT.Selection, new Event()); //select radio button 2

      assertThat(_dialog.getRadioButton2().getSelection()).isTrue(); //check if radio button 2 is selected

      _dialog.getFileChooserButton().notifyListeners(SWT.Selection, new Event()); //click the browse button to open fileChooser

      assertThat(_dialog.getRadioButton2().getSelection()).isTrue(); //after closing the fileChooser, radio button 2 should be still selected - but radio button 1 is selected instead
  }

  private class SimpleDialog extends TitleAreaDialog {

    private boolean _userTest;
    private Button _radio1;
    private Button _radio2;
    private Button _button;

    public SimpleDialog(Shell parentShell, boolean userTest) {
      this(parentShell);
      _userTest = userTest;
    }

    public SimpleDialog(Shell parentShell) {
      super(parentShell);
    }

    @Override
    public void create() {
      super.create();
      setTitle("SWT Radio Buttons");
      setMessage("Select Radio Button 2 and then open the FileChooser and close it afterwards.");
    }

    @Override
    protected Control createDialogArea(Composite parent) {
      Composite area = (Composite) super.createDialogArea(parent);
      Composite container = new Composite(area, SWT.NONE);
      GridDataFactory.fillDefaults().applyTo(container);
      GridLayoutFactory.fillDefaults().applyTo(container);

      createRadioButtons(container);
      createFileChooserButton(container);

      return area;

    }

    private void createRadioButtons(Composite parent) {
      _radio1 = new Button(parent, SWT.RADIO);
      _radio1.setText("Option 1");
      GridDataFactory.fillDefaults().grab(true, false).applyTo(_radio1);

      _radio2 = new Button(parent, SWT.RADIO);
      _radio2.setText("Option 2");
      GridDataFactory.fillDefaults().grab(true, false).applyTo(_radio2);
    }

    private void createFileChooserButton(Composite parent) {
      _button = new Button(parent, SWT.PUSH);
      _button.setText("Browse...");
      _button.addSelectionListener(createSelectionAdapter());
    }

    private SelectionAdapter createSelectionAdapter() {
      if (_userTest) {
        return new SelectionAdapter() {
          @Override
          public void widgetSelected(SelectionEvent e) {
            /**
             * The error only occurs if the current shell is used! If a new shell is created, there is no error behavior.
             */
            FileDialog fileDialog = new FileDialog(getShell(), SWT.OPEN);
            fileDialog.setText("Select File");
            fileDialog.open();
          }
        };
      } else {
        return new SelectionAdapter() {
          @Override
          public void widgetSelected(SelectionEvent e) {
            SimpleDialog simpleDialog = new SimpleDialog(getShell());
            simpleDialog.setBlockOnOpen(false);
            simpleDialog.open();
            simpleDialog.close();
          }
        };
      }
    }

    public Button getRadioButton1() {
      return _radio1;
    }

    public Button getRadioButton2() {
      return _radio2;
    }

    public Button getFileChooserButton() {
      return _button;
    }
  }
}