/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.openmeetings.util;

import static org.apache.openmeetings.util.OpenmeetingsVariables.webAppRootKey;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

import org.red5.logging.Red5LoggerFactory;
import org.slf4j.Logger;

/**
 * @author Sebastian Wagner 27.08.2005 - 19:24:25
 *
 */
public class CalendarPatterns {
	private static final Logger log = Red5LoggerFactory.getLogger(CalendarPatterns.class, webAppRootKey);

	public static ThreadLocal<SimpleDateFormat> dateFormat__ddMMyyyyHHmmss = new ThreadLocal<SimpleDateFormat>() {
		protected SimpleDateFormat initialValue() {
			return new SimpleDateFormat("dd.MM.yyyy HH:mm:ss");
		};
	};
	public static ThreadLocal<SimpleDateFormat> dateFormat__ddMMyyyy = new ThreadLocal<SimpleDateFormat>() {
		protected SimpleDateFormat initialValue() {
			return new SimpleDateFormat("dd.MM.yyyy");
		};
	};
	public static ThreadLocal<SimpleDateFormat> dateFormat__ddMMyyyyBySeparator = new ThreadLocal<SimpleDateFormat>() {
		protected SimpleDateFormat initialValue() {
			return new SimpleDateFormat("dd-MM-yyyy");
		};
	};
	public static ThreadLocal<SimpleDateFormat> dateFormat__yyyyMMddHHmmss = new ThreadLocal<SimpleDateFormat>() {
		protected SimpleDateFormat initialValue() {
			return new SimpleDateFormat("yyyy.MM.dd HH:mm:ss");
		};
	};

	public static String getDateByMiliSeconds(Date t) {
		return dateFormat__yyyyMMddHHmmss.get().format(t);
	}

	public static String getDateWithTimeByMiliSeconds(Date t) {
		return t == null ? null : dateFormat__yyyyMMddHHmmss.get().format(t);
	}

	public static String getDateWithTimeByMiliSecondsWithZone(Date t) {
		if (t == null) {
			return null;
		}
		SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy HH:mm:ss z (Z)");
		Date dateOld = new Date();
		long timeAdv = t.getTime();
		dateOld.setTime(timeAdv);
		String result = sdf.format(dateOld);
		return result;
	}

	public static String getExportDate(Date t) {
		if (t == null) {
			return "";
		}
		return "" + t.getTime();
	}

	public static Date parseImportDate(String dateString) {
		try {

			Date resultDate = null;

			resultDate = validDate(dateFormat__ddMMyyyyHHmmss.get(), dateString);

			if (resultDate != null) {
				return resultDate;
			}

			resultDate = validDate(dateFormat__ddMMyyyy.get(), dateString);

			if (resultDate != null) {
				return resultDate;
			}

			resultDate = validDate(dateString);

			if (dateString != null) {
				return resultDate;
			}

			throw new Exception("Could not parse date string " + dateString);
		} catch (Exception e) {
			log.error("parseDate", e);
		}
		return null;
	}

	private static Date validDate(String testdate) {
		try {

			Long t = Long.valueOf(testdate);

			if (t != null) {
				return new Date(t);
			}

		} catch (Exception err) {
		}
		return null;
	}

	private static Date validDate(SimpleDateFormat sdf, String testdate) {
		Date resultDate = null;
		try {
			resultDate = sdf.parse(testdate);
		}

		// if the format of the string provided doesn't match the format we
		// declared in SimpleDateFormat() we will get an exception

		catch (java.text.ParseException e) {
			return null;
		}

		if (!sdf.format(resultDate).equals(testdate)) {
			return null;
		}

		return resultDate;

	}

	public static String getDateWithTimeByMiliSecondsAndTimeZone(Date t,
			TimeZone timezone) {
		if (t == null) {
			return null;
		}
		SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy HH:mm:ss z (Z)");
		sdf.setTimeZone(timezone);
		Date dateOld = new Date();
		long timeAdv = t.getTime();
		dateOld.setTime(timeAdv);
		String result = sdf.format(dateOld);
		return result;
	}

	public static String getTimeForStreamId(Date t) {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
		Date dateOld = new Date();
		long timeAdv = t.getTime();
		dateOld.setTime(timeAdv);
		String result = sdf.format(dateOld);
		return result;
	}

	public static Date parseDate(String dateString) {
		try {
			return dateFormat__ddMMyyyy.get().parse(dateString);
		} catch (Exception e) {
			log.error("parseDate", e);
		}
		return null;
	}

	public static Date parseDateBySeparator(String dateString) {
		try {
			return dateFormat__ddMMyyyyBySeparator.get().parse(dateString);
		} catch (Exception e) {
			log.error("parseDate", e);
		}
		return null;
	}

	public static Date parseDateWithHour(String dateString) {
		try {
			if (dateString == null || dateString.length() == 0
					|| dateString.equals("null")) {
				return null;
			}
			return dateFormat__ddMMyyyyHHmmss.get().parse(dateString);
		} catch (Exception e) {
			log.error("parseDate", e);
		}
		return null;
	}

	public static String getYear(Date t) {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy");
		Date dateOld = new Date();
		long timeAdv = t.getTime();
		dateOld.setTime(timeAdv);
		String result = sdf.format(dateOld);
		return result;
	}

}