GenericSelect2DropDownSingleChoice.java

package fr.openwide.core.wicket.more.markup.html.select2;

import java.util.Collection;
import java.util.List;

import org.apache.wicket.AttributeModifier;
import org.apache.wicket.Component;
import org.apache.wicket.markup.html.form.DropDownChoice;
import org.apache.wicket.markup.html.form.IChoiceRenderer;
import org.apache.wicket.model.IModel;
import org.apache.wicket.model.LoadableDetachableModel;
import org.retzlaff.select2.Select2Behavior;
import org.retzlaff.select2.Select2Settings;

import fr.openwide.core.wicket.more.markup.html.model.ChoicesWrapperModel;
import fr.openwide.core.wicket.more.markup.html.select2.util.DropDownChoiceWidth;
import fr.openwide.core.wicket.more.markup.html.select2.util.IDropDownChoiceWidth;
import fr.openwide.core.wicket.more.markup.html.select2.util.Select2Utils;

public abstract class GenericSelect2DropDownSingleChoice<T> extends DropDownChoice<T> {
	private static final long serialVersionUID = -3776700270762640109L;
	
	private IDropDownChoiceWidth width = DropDownChoiceWidth.AUTO;
	
	private ChoicesWrapperModel<T> choicesWrapperModel;
	
	private final Select2Behavior<T, T> select2Behavior;
	
	protected GenericSelect2DropDownSingleChoice(String id, IModel<T> model, IModel<? extends Collection<? extends T>> choicesModel, IChoiceRenderer<? super T> renderer) {
		super(id);
		
		setModel(model);
		choicesWrapperModel = new ChoicesWrapperModel<T>(model, choicesModel);
		setChoices(choicesWrapperModel);
		setChoiceRenderer(renderer);
		setNullValid(true);
		
		select2Behavior = Select2Behavior.forChoice(this);
		fillSelect2Settings(select2Behavior.getSettings());
		add(select2Behavior);
	}

	@SuppressWarnings("unchecked")
	protected void ensureChoicesModelIsWrapped() {
		/*
		 * Ideally this wrapping should be done in setChoices(IModel) or in wrap(IModel),
		 * but those methods cannot be overriden...
		 */
		IModel<? extends List<? extends T>> choicesModel = getChoicesModel();
		if (choicesModel != choicesWrapperModel) {
			if (choicesModel instanceof ChoicesWrapperModel) {
				this.choicesWrapperModel = (ChoicesWrapperModel<T>) choicesModel;
			} else {
				this.choicesWrapperModel = new ChoicesWrapperModel<>(getModel(), choicesModel);
				setChoices(choicesWrapperModel);
			}
		}
	}
	
	@Override
	protected void onInitialize() {
		ensureChoicesModelIsWrapped();
		
		super.onInitialize();
		
		add(new AttributeModifier("style", new LoadableDetachableModel<String>() {
			private static final long serialVersionUID = 1L;
			
			@Override
			protected String load() {
				return "width: " + width.getWidth();
			}
		}) {
			private static final long serialVersionUID = 1L;

			@Override
			public boolean isEnabled(Component component) {
				return width != null;
			}
		});
	}
	
	@Override
	protected void onConfigure() {
		ensureChoicesModelIsWrapped();
		
		super.onConfigure();
		
		if (isRequired()) {
			Select2Utils.setRequiredSettings(getSettings());
		}
	}
	
	protected void fillSelect2Settings(Select2Settings settings) {
		Select2Utils.setDefaultSettings(settings);
	}
	
	protected final Select2Settings getSettings() {
		return select2Behavior.getSettings();
	}
	
	public GenericSelect2DropDownSingleChoice<T> setWidth(IDropDownChoiceWidth width) {
		this.width = width;
		return this;
	}
	
	protected String getRootKey() {
		return GenericSelect2DropDownSingleChoice.class.getSimpleName() + "." + this.getId();
	}
	
	@Override
	protected String getNullKey() {
		return getRootKey() + ".null";
	}
	
	@Override
	protected String getNullValidKey() {
		return getRootKey() + ".nullValid";
	}
	
	public boolean isSelectedObjectForcedInChoices() {
		return choicesWrapperModel.isSelectedObjectForcedInChoices();
	}
	
	public GenericSelect2DropDownSingleChoice<T> setSelectedObjectForcedInChoices(boolean selectedObjectForcedInChoices) {
		choicesWrapperModel.setSelectedObjectForcedInChoices(selectedObjectForcedInChoices);
		return this;
	}
	
	@Override
	protected void onDetach() {
		super.onDetach();
		if (choicesWrapperModel != null) {
			choicesWrapperModel.detach();
		}
	}
}