Calendar.java

/*
 *  Copyright 2008 University of Prince Edward Island
 *
 *  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 ca.upei.ic.timetable.client;

import java.util.HashSet;
import java.util.Set;

import org.webinit.gwt.client.KeyValueCodingObserving;
import org.webinit.gwt.client.Observable;

/**
 * This is a managed Calendar class.
 * 
 * This class is managed by WIObjects that provides KeyValueCoding and general
 * observable/observer services.
 * 
 * @author felix
 *
 */
public abstract class Calendar implements Observable, KeyValueCodingObserving {
	
	public final static int RESOLUTION = 15;

	public final static int SUNDAY = 0;
	public final static int MONDAY = 1;
	public final static int TUESDAY = 2;
	public final static int WEDNESDAY = 3;
	public final static int THURSDAY = 4;
	public final static int FRIDAY = 5;
	public final static int SATURDAY = 6;
	
	public final static int FIVE = 5;
	public final static int SEVEN = 7;

	private int type_;
	private Set<CalendarItem> items_;
	
	/**
	 * Create a Calendar
	 * 
	 * setType must be called after the Calendar is created.
	 */
	public Calendar() {
		items_ = new HashSet<CalendarItem>();
	}
	
	/**
	 * Create a Calendar with a type
	 * 
	 * @param type
	 */
	public Calendar(int type) {
		this();
		setType(type);
	}
	
	/**
	 * Set the type of the Calendar
	 * 
	 * @param type
	 */
	public void setType(int type) {
		type_ = type;
		
		switch(type_) {
		case FIVE:
		case SEVEN:
			break;
		default:
			throw new IllegalArgumentException("Invalid Calendar type.");
		}	
	}
	
	public int getType() {
		return type_;
	}
	
	/**
	 * Add an CalendarItem to the Calendar
	 * 
	 * @param item
	 */
	public void addItem(CalendarItem item) {
		trigger("itemWillAdd", this, item);
		if (trigger("itemShouldAdd", this, item)) {
			items_.add(item);
			trigger("itemDidAdd", this, item);
		}
	}
	
	/**
	 * Remove an CalendarItem from the Calendar
	 * 
	 * @param item
	 * @return true the item exists.
	 */
	public boolean removeItem(CalendarItem item) {
		trigger("itemWillRemove", this, item);
		boolean result = false;
		if (trigger("itemShouldAdd", this, item))
			result = items_.remove(item);
		if (result)
			trigger("itemDidRemove", this, item);
		return result;
	}

	/**
	 * Get all CalendarItems of a day
	 * 
	 * @param day
	 * @return a Set of CalendarItems that occupy that day.
	 */
	public Set<CalendarItem> getItemsOfDay(int day) {
		final Set<CalendarItem> items = new HashSet<CalendarItem>();
		for (CalendarItem item: items_) {
			if (item.hasDay(day)) {
				items.add(item);
			}
		}
		return items;
	}
	
}