/*
    * 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.juneau.commons.time;
  
  import static org.junit.jupiter.api.Assertions.*;
  
  import java.time.*;
  import java.time.temporal.ChronoUnit;
  
  import org.apache.juneau.*;
  import org.junit.jupiter.api.*;
  
  /**
   * Tests for {@link TimeProvider}.
   */
  class TimeProvider_Test extends TestBase {
  
  	//====================================================================================================
  	// INSTANCE field tests
  	//====================================================================================================
  
  	@Test
  	void a01_instanceNotNull() {
  		assertNotNull(TimeProvider.INSTANCE);
  	}
  
  	//====================================================================================================
  	// getSystemDefaultZoneId() tests
  	//====================================================================================================
  
  	@Test
  	void b01_getSystemDefaultZoneId() {
  		ZoneId expected = ZoneId.systemDefault();
  		ZoneId actual = TimeProvider.INSTANCE.getSystemDefaultZoneId();
  		assertEquals(expected, actual);
  	}
  
  	@Test
  	void b02_getSystemDefaultZoneId_notNull() {
  		ZoneId zoneId = TimeProvider.INSTANCE.getSystemDefaultZoneId();
  		assertNotNull(zoneId);
  	}
  
  	//====================================================================================================
  	// now() tests
  	//====================================================================================================
  
  	@Test
  	void c01_now() {
  		ZonedDateTime now = TimeProvider.INSTANCE.now();
  		assertNotNull(now);
  		assertEquals(ZoneId.systemDefault(), now.getZone());
  	}
  
  	@Test
  	void c02_now_isRecent() {
  		ZonedDateTime before = ZonedDateTime.now();
  		ZonedDateTime now = TimeProvider.INSTANCE.now();
  		ZonedDateTime after = ZonedDateTime.now();
  
  		// The time should be between before and after (with some tolerance)
  		assertTrue(now.isAfter(before.minusSeconds(1)) || now.isEqual(before.minusSeconds(1)));
  		assertTrue(now.isBefore(after.plusSeconds(1)) || now.isEqual(after.plusSeconds(1)));
  	}
  
  	@Test
  	void c03_now_usesSystemDefaultZone() {
  		ZonedDateTime now = TimeProvider.INSTANCE.now();
  		assertEquals(ZoneId.systemDefault(), now.getZone());
  	}
  
  	//====================================================================================================
  	// now(ZoneId) tests
  	//====================================================================================================
  
  	@Test
  	void d01_nowWithZoneId() {
  		ZoneId utc = ZoneId.of("UTC");
  		ZonedDateTime now = TimeProvider.INSTANCE.now(utc);
  		assertNotNull(now);
  		assertEquals(utc, now.getZone());
  	}
  
  	@Test
  	void d02_nowWithZoneId_usesSpecifiedZone() {
 		ZoneId newYork = ZoneId.of("America/New_York");
 		ZonedDateTime now = TimeProvider.INSTANCE.now(newYork);
 		assertEquals(newYork, now.getZone());
 	}
 
 	@Test
 	void d03_nowWithZoneId_isRecent() {
 		ZoneId utc = ZoneId.of("UTC");
 		ZonedDateTime before = ZonedDateTime.now(utc);
 		ZonedDateTime now = TimeProvider.INSTANCE.now(utc);
 		ZonedDateTime after = ZonedDateTime.now(utc);
 
 		// The time should be between before and after (with some tolerance)
 		assertTrue(now.isAfter(before.minusSeconds(1)) || now.isEqual(before.minusSeconds(1)));
 		assertTrue(now.isBefore(after.plusSeconds(1)) || now.isEqual(after.plusSeconds(1)));
 	}
 
 	@Test
 	void d04_nowWithZoneId_differentZones() {
 		ZoneId utc = ZoneId.of("UTC");
 		ZoneId newYork = ZoneId.of("America/New_York");
 
 		ZonedDateTime utcTime = TimeProvider.INSTANCE.now(utc);
 		ZonedDateTime nyTime = TimeProvider.INSTANCE.now(newYork);
 
 		// Both should represent the same instant, just in different zones
 		Instant utcInstant = utcTime.toInstant();
 		Instant nyInstant = nyTime.toInstant();
 
 		// They should be very close (within 1 second)
 		long diffSeconds = Math.abs(ChronoUnit.SECONDS.between(utcInstant, nyInstant));
 		assertTrue(diffSeconds < 2, "Times should be within 1 second of each other");
 	}
 
 	@Test
 	void d05_nowWithZoneId_nullThrowsException() {
 		assertThrows(NullPointerException.class, () -> {
 			TimeProvider.INSTANCE.now(null);
 		});
 	}
 
 	//====================================================================================================
 	// Custom instance tests
 	//====================================================================================================
 
 	@Test
 	void e01_customInstance() {
 		TimeProvider provider = new TimeProvider();
 		assertNotNull(provider);
 		assertNotNull(provider.getSystemDefaultZoneId());
 		assertNotNull(provider.now());
 	}
 
 	@Test
 	void e02_customInstance_behaviorMatchesInstance() {
 		TimeProvider custom = new TimeProvider();
 		ZoneId customZone = custom.getSystemDefaultZoneId();
 		ZoneId instanceZone = TimeProvider.INSTANCE.getSystemDefaultZoneId();
 		assertEquals(instanceZone, customZone);
 	}
 }