/*
 * Copyright 2002-2013 the original author or authors.
 *
 * Licensed 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.springframework.messaging.support;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import org.junit.Test;
import org.springframework.messaging.MessageHeaders;

import static org.junit.Assert.*;

/**
 * Test fixture for {@link MessageHeaderAccessor}.
 *
 * @author Rossen Stoyanchev
 */
public class MessageHeaderAccessorTests {


	@Test
	public void empty() {
		MessageHeaderAccessor headers = new MessageHeaderAccessor();
		assertEquals(Collections.emptyMap(), headers.toMap());
	}

	@Test
	public void wrapMessage() {
		Map<String, Object> original = new HashMap<>();
		original.put("foo", "bar");
		original.put("bar", "baz");
		GenericMessage<String> message = new GenericMessage<>("payload", original);

		MessageHeaderAccessor headers = new MessageHeaderAccessor(message);
		Map<String, Object> actual = headers.toMap();

		assertEquals(4, actual.size());
		assertNotNull(actual.get(MessageHeaders.ID));
		assertNotNull(actual.get(MessageHeaders.TIMESTAMP));
		assertEquals("bar", actual.get("foo"));
		assertEquals("baz", actual.get("bar"));
	}

	@Test
	public void wrapMessageAndModifyHeaders() {
		Map<String, Object> original = new HashMap<>();
		original.put("foo", "bar");
		original.put("bar", "baz");
		GenericMessage<String> message = new GenericMessage<>("payload", original);

		MessageHeaderAccessor headers = new MessageHeaderAccessor(message);
		headers.setHeader("foo", "BAR");
		Map<String, Object> actual = headers.toMap();

		assertEquals(4, actual.size());
		assertNotNull(actual.get(MessageHeaders.ID));
		assertNotNull(actual.get(MessageHeaders.TIMESTAMP));
		assertEquals("BAR", actual.get("foo"));
		assertEquals("baz", actual.get("bar"));
	}

	@Test
	public void copyHeadersNullMap() {
		MessageHeaderAccessor headers = new MessageHeaderAccessor();
		headers.copyHeaders(null);
		headers.copyHeadersIfAbsent(null);

		assertEquals(0, headers.toMap().size());
	}

}
