/*
 * Copyright 2002-2019 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
 *
 *      https://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.core.codec;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.Map;

import org.junit.Test;
import org.reactivestreams.Publisher;
import reactor.core.publisher.Flux;
import reactor.test.StepVerifier;

import org.springframework.core.ResolvableType;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.InputStreamResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.lang.Nullable;
import org.springframework.util.MimeType;
import org.springframework.util.MimeTypeUtils;
import org.springframework.util.StreamUtils;

import static org.junit.Assert.*;
import static org.springframework.core.ResolvableType.forClass;

/**
 * @author Arjen Poutsma
 */
public class ResourceDecoderTests extends AbstractDecoderTestCase<ResourceDecoder> {

	private final byte[] fooBytes = "foo".getBytes(StandardCharsets.UTF_8);

	private final byte[] barBytes = "bar".getBytes(StandardCharsets.UTF_8);


	public ResourceDecoderTests() {
		super(new ResourceDecoder());
	}

	@Override
	@Test
	public void canDecode() {
		assertTrue(this.decoder.canDecode(forClass(InputStreamResource.class), MimeTypeUtils.TEXT_PLAIN));
		assertTrue(this.decoder.canDecode(forClass(ByteArrayResource.class), MimeTypeUtils.TEXT_PLAIN));
		assertTrue(this.decoder.canDecode(forClass(Resource.class), MimeTypeUtils.TEXT_PLAIN));
		assertTrue(this.decoder.canDecode(forClass(InputStreamResource.class), MimeTypeUtils.APPLICATION_JSON));
		assertFalse(this.decoder.canDecode(forClass(Object.class), MimeTypeUtils.APPLICATION_JSON));
	}


	@Override
	@Test
	public void decode() {
		Flux<DataBuffer> input = Flux.concat(
				dataBuffer(this.fooBytes),
				dataBuffer(this.barBytes));

		testDecodeAll(input, Resource.class, step -> step
				.consumeNextWith(resource -> {
					try {
						byte[] bytes = StreamUtils.copyToByteArray(resource.getInputStream());
						assertEquals("foobar", new String(bytes));
					}
					catch (IOException e) {
						fail(e.getMessage());
					}
				})
				.expectComplete()
				.verify());
	}

	@Override
	protected void testDecodeError(Publisher<DataBuffer> input, ResolvableType outputType,
			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {

		input = Flux.concat(
				Flux.from(input).take(1),
				Flux.error(new InputException()));

		Flux<Resource> result = this.decoder.decode(input, outputType, mimeType, hints);

		StepVerifier.create(result)
				.expectError(InputException.class)
				.verify();
	}

	@Override
	public void decodeToMono() {
		Flux<DataBuffer> input = Flux.concat(
				dataBuffer(this.fooBytes),
				dataBuffer(this.barBytes));

		testDecodeToMonoAll(input, ResolvableType.forClass(Resource.class),
				step -> step
						.consumeNextWith(value -> {
							Resource resource = (Resource) value;
							try {
								byte[] bytes = StreamUtils.copyToByteArray(resource.getInputStream());
								assertEquals("foobar", new String(bytes));
								assertEquals("testFile", resource.getFilename());
							}
							catch (IOException e) {
								fail(e.getMessage());
							}
						})
						.expectComplete()
						.verify(),
				null,
				Collections.singletonMap(ResourceDecoder.FILENAME_HINT, "testFile"));
	}

}
