// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.GWT.client.widgets.nonpublic;

import com.google.gwt.user.client.*;
import com.google.gwt.user.client.ui.*;

public abstract class AbstractLowLevelSizeableComposite extends AbstractSizeableWidget implements WidgetCompositor {
    private Widget mWidget;

    @Override
    public Element getElement() {
        if ( mWidget == null ) {
            throw new IllegalStateException( "initWidget() was never called in " + getClass().getName() );
        }
        return super.getElement();
    }

    @Override
    public Widget[] getCompositedWidgets() {
        return new Widget[]{mWidget};
    }

    /**
     * Sets the widget to be wrapped by the composite. The wrapped widget must be
     * set before calling any {@link Widget} methods on this object, or adding it
     * to a panel. This method may only be called once for a given composite.
     *
     * @param pWidget the widget to be wrapped
     */
    protected void LLinitWidget( Widget pWidget ) {
        // Make sure the widget is not being set twice.
        if ( mWidget != null ) {
            throw new IllegalStateException( "Composite.initWidget() may only be called once." );
        }

        pWidget.removeFromParent();

        // Use the contained widget's element as the composite's element,
        // effectively merging them within the DOM.
        setElement( pWidget.getElement() );

        //noinspection NonJREEmulationClassesInClientCode
        BackDoorToWidget.setParent( mWidget = pWidget, this ); // The Composite now owns this widget.

        initialize();
    }

    @Override
    protected void onAttach() {
        super.onAttach();

        //noinspection NonJREEmulationClassesInClientCode
        BackDoorToWidget.onAttach( mWidget ); // Call onAttach() on behalf of the contained widget.
    }

    @Override
    protected void onDetach() {
        super.onDetach();

        //noinspection NonJREEmulationClassesInClientCode
        BackDoorToWidget.onDetach( mWidget ); // Call onDetach() on behalf of the contained widget.
    }

    public Widget LLgetWidget() {
        return mWidget;
    }
}