import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class DateUtils {
	private static final long ONE_MINUTE = 60;
	private static final long ONE_HOUR = 3600;
	private static final long ONE_DAY = 86400;
	private static final long ONE_MONTH = 2592000;
	private static final long ONE_YEAR = 31104000;

	public static Calendar calendar = Calendar.getInstance();

	/**
	 * 
	 * @return yyyy-mm-dd
	 *  2012-12-25
	 */
	public static String getDate() {
		return getYear() + "-" + getMonth() + "-" + getDay();
	}

	/**
	 * @param format
	 * @return 
	 * yyyy年MM月dd HH:mm 
	 * MM-dd HH:mm 2012-12-25
	 * 
	 */
	public static String getDate(String format) {
		SimpleDateFormat simple = new SimpleDateFormat(format);
		return simple.format(calendar.getTime());
	}

	/**
	 * 
	 * @return yyyy-MM-dd HH:mm 
	 * 2012-12-29 23:47
	 */
	public static String getDateAndMinute() {
		SimpleDateFormat simple = new SimpleDateFormat("yyyy-MM-dd HH:mm");
		return simple.format(calendar.getTime());
	}

	/**
	 * 
	 * @return
	 *  yyyy-MM-dd HH:mm:ss 
	 *  2012-12-29 23:47:36
	 */
	public static String getFullDate() {
		SimpleDateFormat simple = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		return simple.format(calendar.getTime());
	}

	/**
	 * 距离今天多久
	 * @param date
	 * @return 
	 * 
	 */
	public static String fromToday(Date date) {
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(date);

		long time = date.getTime() / 1000;
		long now = new Date().getTime() / 1000;
		long ago = now - time;
		if (ago <= ONE_HOUR)
			return ago / ONE_MINUTE + "分钟前";
		else if (ago <= ONE_DAY)
			return ago / ONE_HOUR + "小时" + (ago % ONE_HOUR / ONE_MINUTE)
					+ "分钟前";
		else if (ago <= ONE_DAY * 2)
			return "昨天" + calendar.get(Calendar.HOUR_OF_DAY) + "点"
					+ calendar.get(Calendar.MINUTE) + "分";
		else if (ago <= ONE_DAY * 3)
			return "前天" + calendar.get(Calendar.HOUR_OF_DAY) + "点"
					+ calendar.get(Calendar.MINUTE) + "分";
		else if (ago <= ONE_MONTH) {
			long day = ago / ONE_DAY;
			return day + "天前" + calendar.get(Calendar.HOUR_OF_DAY) + "点"
					+ calendar.get(Calendar.MINUTE) + "分";
		} else if (ago <= ONE_YEAR) {
			long month = ago / ONE_MONTH;
			long day = ago % ONE_MONTH / ONE_DAY;
			return month + "个月" + day + "天前"
					+ calendar.get(Calendar.HOUR_OF_DAY) + "点"
					+ calendar.get(Calendar.MINUTE) + "分";
		} else {
			long year = ago / ONE_YEAR;
			int month = calendar.get(Calendar.MONTH) + 1;// JANUARY which is 0 so month+1
			return year + "年前" + month + "月" + calendar.get(Calendar.DATE)
					+ "日";
		}

	}

	/**
	 * 距离截止日期还有多长时间
	 * 
	 * @param date
	 * @return
	 */
	public static String fromDeadline(Date date) {
		long deadline = date.getTime() / 1000;
		long now = (new Date().getTime()) / 1000;
		long remain = deadline - now;
		if (remain <= ONE_HOUR)
			return "只剩下" + remain / ONE_MINUTE + "分钟";
		else if (remain <= ONE_DAY)
			return "只剩下" + remain / ONE_HOUR + "小时"
					+ (remain % ONE_HOUR / ONE_MINUTE) + "分钟";
		else {
			long day = remain / ONE_DAY;
			long hour = remain % ONE_DAY / ONE_HOUR;
			long minute = remain % ONE_DAY % ONE_HOUR / ONE_MINUTE;
			return "只剩下" + day + "天" + hour + "小时" + minute + "分钟";
		}

	}

	/**
	 * 距离今天的绝对时间
	 * 
	 * @param date
	 * @return
	 */
	public static String toToday(Date date) {
		long time = date.getTime() / 1000;
		long now = (new Date().getTime()) / 1000;
		long ago = now - time;
		if (ago <= ONE_HOUR)
			return ago / ONE_MINUTE + "分钟";
		else if (ago <= ONE_DAY)
			return ago / ONE_HOUR + "小时" + (ago % ONE_HOUR / ONE_MINUTE) + "分钟";
		else if (ago <= ONE_DAY * 2)
			return "昨天" + (ago - ONE_DAY) / ONE_HOUR + "点" + (ago - ONE_DAY)
					% ONE_HOUR / ONE_MINUTE + "分";
		else if (ago <= ONE_DAY * 3) {
			long hour = ago - ONE_DAY * 2;
			return "前天" + hour / ONE_HOUR + "点" + hour % ONE_HOUR / ONE_MINUTE
					+ "分";
		} else if (ago <= ONE_MONTH) {
			long day = ago / ONE_DAY;
			long hour = ago % ONE_DAY / ONE_HOUR;
			long minute = ago % ONE_DAY % ONE_HOUR / ONE_MINUTE;
			return day + "天前" + hour + "点" + minute + "分";
		} else if (ago <= ONE_YEAR) {
			long month = ago / ONE_MONTH;
			long day = ago % ONE_MONTH / ONE_DAY;
			long hour = ago % ONE_MONTH % ONE_DAY / ONE_HOUR;
			long minute = ago % ONE_MONTH % ONE_DAY % ONE_HOUR / ONE_MINUTE;
			return month + "个月" + day + "天" + hour + "点" + minute + "分前";
		} else {
			long year = ago / ONE_YEAR;
			long month = ago % ONE_YEAR / ONE_MONTH;
			long day = ago % ONE_YEAR % ONE_MONTH / ONE_DAY;
			return year + "年前" + month + "月" + day + "天";
		}

	}

	public static String getYear() {
		return calendar.get(Calendar.YEAR) + "";
	}

	public static String getMonth() {
		int month = calendar.get(Calendar.MONTH) + 1;
		return month + "";
	}

	public static String getDay() {
		return calendar.get(Calendar.DATE) + "";
	}

	public static String get24Hour() {
		return calendar.get(Calendar.HOUR_OF_DAY) + "";
	}

	public static String getMinute() {
		return calendar.get(Calendar.MINUTE) + "";
	}

	public static String getSecond() {
		return calendar.get(Calendar.SECOND) + "";
	}

	public static void main(String[] args) throws ParseException {
		String deadline = "2012-12-30 12:45:59";
		Date date = new Date();
		SimpleDateFormat simple = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		date = simple.parse(deadline);
		System.out.println(DateUtils.fromDeadline(date));

		String before = "2012-12-12 0:0:59";
		date = simple.parse(before);
		System.out.println(DateUtils.fromToday(date));

		System.out.println(DateUtils.getFullDate());
		System.out.println(DateUtils.getDate());
	}

}