/*
 * Copyright 2007 Future Earth, info@future-earth.eu
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package eu.future.earth.gwt.client.date;

import java.util.Date;

import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.Widget;

public abstract class EventPanel<T> extends SimplePanel implements HasDateEventHandlers<T>, Comparable<EventPanel<T>> {

	private T value = null;

	private TimeEventRenderer<T> renderer = null;

	@SuppressWarnings("unchecked")
	protected EventPanel(TimeEventRenderer<? extends T> newRenderer, T newData) {
		super();
		renderer = (TimeEventRenderer<T>) newRenderer;
		value = newData;
	}

	public abstract void setContentHeight(int height);

	public abstract int getContentHeight();

	public abstract void setWidth(int width);

	public int compareTo(EventPanel<T> other) {
		Date one = getStart();
		Date two = other.getStart();
		if (one != null) {
			return one.compareTo(two);
		}
		return 0;
	}

	private String eventStyleName = null;

	public String getEventStyleName() {
		return eventStyleName;
	}

	public void setEventStyleName(String eventStyleName) {
		this.eventStyleName = eventStyleName;
	}

	public void setStart(Date newStart) {
		if (value != null) {
			renderer.setStartTime(value, newStart);
		}
	}

	public int getPosY() {
		return posY;
	}

	public void setPosY(int posY) {
		this.posY = posY;
	}

	private int posY = 0;

	public void setEndTime(Date newEnd) {
		if (value != null) {
			renderer.setEndTime(value, newEnd);
		}
	}

	public Date getStart() {
		if (value != null) {
			return renderer.getStartTime(value);
		} else {
			return null;
		}
	}

	public Date getEnd() {
		if (value != null) {
			return renderer.getEndTime(value);
		} else {
			return null;
		}
	}

	public T getValue() {
		return value;
	}

	public void setValue(T value) {
		this.value = value;
	}

	private HandlerRegistration parent = null;

	public void addParentDateEventHandler(DateEventListener<? extends T> handler) {
		parent = addDateEventHandler(handler);
	}

	public void clearParent() {
		if (parent != null) {
			parent.removeHandler();
		}
	}

	public HandlerRegistration addDateEventHandler(DateEventListener<? extends T> handler) {
		return addHandler(handler, DateEvent.getType());
	}

	/**
	 * Indicates whether some other object is "equal to" this one.
	 * 
	 * @param obj
	 *            the reference object with which to compare.
	 * @return <code>true</code> if this object is the same as the obj argument; <code>false</code> otherwise.
	 * @todo Implement this java.lang.Object method
	 */
	@SuppressWarnings("unchecked")
	public boolean equals(Object obj) {
		if (obj instanceof EventPanel<?>) {
			final EventPanel<? extends T> real = (EventPanel<? extends T>) obj;
			if (renderer == null) {
				return value.equals(real.getValue());
			}
			if (renderer.equal(value, real.getValue())) {
				return true;
			}
		}
		return false;
	}

	public boolean isDraggable() {
		if (renderer == null) {
			return false;
		}
		return renderer.enableDragAndDrop();
	}

	public abstract void repaintTime();

	public abstract Widget getDraggableItem();

}