package foundation.period;

import java.util.Calendar;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;

import foundation.variant.provider.DataEvent;
import foundation.variant.provider.IVariantsProvider;
import foundation.variant.provider.VariantCenter;
import foundation.variant.provider.VariantExistsException;
import foundation.variant.provider.VariantProviderType;


public class ActivePeriod implements IVariantsProvider { 
	
	public static String ProviderName = "activePeriod";
	private static ActivePeriod instance;
	private static Object lock = new Object();
	private String id;
	private int year;
	private int month;
	private int day;
	private int monthNo;
	private static Set<String> paramNames;
	
	
	static {
		createInstance();
	}
	
	private ActivePeriod() {
		paramNames = new HashSet<String>();
		
		Date now = new Date();
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(now);
		
		year = calendar.get(Calendar.YEAR);
		month = calendar.get(Calendar.MONTH) + 1;
		day = calendar.get(Calendar.DAY_OF_MONTH);
		monthNo = year * 100 + month;
	}
	
	public static ActivePeriod getInstance() {
		if (instance == null) {
			synchronized (lock) {
				if (instance == null) {
					instance = new ActivePeriod();
				}
			}
		}
		
		return instance;
	}
	
	public static synchronized ActivePeriod createInstance() {
		instance = new ActivePeriod();
		return instance;
	}
	
	public static void init(String id, int year, int month) throws VariantExistsException {
		ActivePeriod period = getInstance();
		
		period.id = id;
		period.year = year;
		period.month = month;
		period.monthNo = year * 100 + month;
		
		paramNames.add("period.year");
		paramNames.add("period.month");
		paramNames.add("period.monthno");
		
		VariantCenter.getInstance().registPersist(paramNames, period);
	}

	public String getId() {
		return instance.id;
	}

	public static int getYear() {
		return instance.year;
	}

	public static int getMonth() {
		return instance.month;
	}

	public static int getDay() {
		return instance.day;
	}	
	
	public static int getMonthNo() {
		return instance.monthNo;
	}

	@Override
	public String getProviderName() {
		return ProviderName;
	}

	@Override
	public VariantProviderType getProviderType() {
		return VariantProviderType.Persist;
	}

	@Override
	public boolean containsVariant(String name) {
		if (name == null) {
			return false;
		}
		
		return paramNames.contains(name);
	}

	@Override
	public Object getVariantValue(DataEvent dataEvent, String name) {
		if (name == null) {
			return null;
		}
		
		name = name.toLowerCase();
		
		if ("period.year".equals(name)) {
			return String.valueOf(year);
		}
		else if ("period.month".equals(name)) {
			return String.valueOf(month);
		}
		else if ("period.monthno".equals(name)) {
			return String.valueOf(monthNo);
		}
		
		return null;
	}

	@Override
	public Set<String> getVariantNames() {
		return paramNames;
	}

}