/**
 * Licensed to Apereo under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership. Apereo
 * 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 the
 * following location:
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0
 *
 * <p>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.apereo.portal.test;

import java.util.TimeZone;
import org.joda.time.DateTimeZone;
import org.junit.AfterClass;
import org.junit.BeforeClass;

/**
 * Utility for setting the TZ during a unit test. {@link #beforeTest()} should be called in a {@link
 * BeforeClass} method and {@link #afterTest()} should be called in a {@link AfterClass} block
 *
 */
public final class TimeZoneTestUtils {
    private final DateTimeZone testTimeZone;

    private TimeZone defaultTimeZone;
    private DateTimeZone defaultDateTimeZone;
    private String defaultUserTimezone;

    public TimeZoneTestUtils() {
        this(DateTimeZone.UTC);
    }

    public TimeZoneTestUtils(DateTimeZone testTimeZone) {
        this.testTimeZone = testTimeZone;
    }

    public void beforeTest() {
        defaultTimeZone = TimeZone.getDefault();
        defaultDateTimeZone = DateTimeZone.getDefault();
        defaultUserTimezone = System.getProperty("user.timezone");

        TimeZone.setDefault(testTimeZone.toTimeZone());
        DateTimeZone.setDefault(testTimeZone);
        System.setProperty("user.timezone", testTimeZone.getID());
    }

    public void afterTest() {
        if (defaultTimeZone != null) {
            TimeZone.setDefault(defaultTimeZone);
        }
        if (defaultDateTimeZone != null) {
            DateTimeZone.setDefault(defaultDateTimeZone);
        }
        if (defaultUserTimezone != null) {
            System.setProperty("user.timezone", defaultUserTimezone);
        }
    }
}