package com.googlecode.gwt.test.uibinder.widget;

import com.google.gwt.dom.client.Element;
import com.google.gwt.user.client.ui.CellPanel;
import com.google.gwt.user.client.ui.HasHorizontalAlignment.HorizontalAlignmentConstant;
import com.google.gwt.user.client.ui.HasVerticalAlignment.VerticalAlignmentConstant;
import com.google.gwt.user.client.ui.IsWidget;
import com.googlecode.gwt.test.uibinder.UiBinderXmlUtils;
import com.googlecode.gwt.test.uibinder.UiObjectTag;
import com.googlecode.gwt.test.uibinder.UiObjectTagFactory;

import java.util.List;
import java.util.Map;

/**
 * Handles subclasses of CellPanel (which declare <g:cell> tags).
 *
 * @author Gael Lazzari
 */
public class UiCellPanelTagFactory implements UiObjectTagFactory<CellPanel> {

    private static class UiCellPanelTag extends UiObjectTag<CellPanel> {

        private static final String CELL_TAG = "cell";

        @Override
        protected void appendElement(CellPanel wrapped, Element element, String namespaceURI,
                                     List<IsWidget> childWidgets) {

            if (!CELL_TAG.equals(element.getTagName())
                    || !UiBinderXmlUtils.CLIENTUI_NSURI.equals(namespaceURI)) {
                super.appendElement(wrapped, element, namespaceURI, childWidgets);
            } else {

                // hanle cell's attributes
                String width = element.getAttribute("width");
                if (width == null || width.trim().length() == 0) {
                    width = null;
                }

                String horizontalAlignment = element.getAttribute("horizontalAlignment");
                HorizontalAlignmentConstant hConstant = null;
                if (horizontalAlignment != null && horizontalAlignment.trim().length() > 0) {
                    hConstant = UiBinderXmlUtils.parseHorizontalAlignment(horizontalAlignment.trim());
                }

                String verticalAlignment = element.getAttribute("verticalAlignment");
                VerticalAlignmentConstant vConstant = null;
                if (verticalAlignment != null && verticalAlignment.trim().length() > 0) {
                    vConstant = UiBinderXmlUtils.parseVerticalAlignment(verticalAlignment.trim());
                }

                // handle cell's child widget and set cell's attributes
                for (IsWidget widget : childWidgets) {
                    wrapped.add(widget);
                    if (width != null) {
                        wrapped.setCellWidth(widget, width);
                    }
                    if (hConstant != null) {
                        wrapped.setCellHorizontalAlignment(widget, hConstant);
                    }
                    if (vConstant != null) {
                        wrapped.setCellVerticalAlignment(widget, vConstant);
                    }
                }

            }
        }

        @Override
        protected void finalizeObject(CellPanel widget) {
            // nothing to do
        }

        @Override
        protected void initializeObject(CellPanel wrapped, Map<String, Object> attributes,
                                        Object owner) {
            // nothing to do
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see com.googlecode.gwt.test.uibinder.UiObjectTagFactory#createUiObjectTag (java.lang.Class,
     * java.util.Map)
     */
    public UiObjectTag<CellPanel> createUiObjectTag(Class<?> clazz, Map<String, Object> attributes) {
        if (!CellPanel.class.isAssignableFrom(clazz)) {
            return null;
        }

        return new UiCellPanelTag();
    }

}