/*
 * Copyright 2012-present 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.boot.test.context;

import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;

import org.junit.jupiter.api.Test;

import org.springframework.core.io.ClassPathResource;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;

/**
 * Tests for {@link FilteredClassLoader}.
 *
 * @author Phillip Webb
 * @author Roy Jacobs
 */
class FilteredClassLoaderTests {

	static ClassPathResource TEST_RESOURCE = new ClassPathResource(
			"org/springframework/boot/test/context/FilteredClassLoaderTestsResource.txt");

	@Test
	void loadClassWhenFilteredOnPackageShouldThrowClassNotFound() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader(
				FilteredClassLoaderTests.class.getPackage().getName())) {
			assertThatExceptionOfType(ClassNotFoundException.class)
				.isThrownBy(() -> Class.forName(getClass().getName(), false, classLoader));
		}
	}

	@Test
	void loadClassWhenFilteredOnClassShouldThrowClassNotFound() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader(FilteredClassLoaderTests.class)) {
			assertThatExceptionOfType(ClassNotFoundException.class)
				.isThrownBy(() -> Class.forName(getClass().getName(), false, classLoader));
		}
	}

	@Test
	void loadClassWhenNotFilteredShouldLoadClass() throws Exception {
		FilteredClassLoader classLoader = new FilteredClassLoader((className) -> false);
		Class<?> loaded = Class.forName(getClass().getName(), false, classLoader);
		assertThat(loaded.getName()).isEqualTo(getClass().getName());
		classLoader.close();
	}

	@Test
	void loadResourceWhenFilteredOnResourceShouldReturnNotFound() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader(TEST_RESOURCE)) {
			final URL loaded = classLoader.getResource(TEST_RESOURCE.getPath());
			assertThat(loaded).isNull();
		}
	}

	@Test
	void loadResourceWhenNotFilteredShouldLoadResource() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader((resourceName) -> false)) {
			final URL loaded = classLoader.getResource(TEST_RESOURCE.getPath());
			assertThat(loaded).isNotNull();
		}
	}

	@Test
	void loadResourcesWhenFilteredOnResourceShouldReturnNotFound() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader(TEST_RESOURCE)) {
			final Enumeration<URL> loaded = classLoader.getResources(TEST_RESOURCE.getPath());
			assertThat(loaded.hasMoreElements()).isFalse();
		}
	}

	@Test
	void loadResourcesWhenNotFilteredShouldLoadResource() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader((resourceName) -> false)) {
			final Enumeration<URL> loaded = classLoader.getResources(TEST_RESOURCE.getPath());
			assertThat(loaded.hasMoreElements()).isTrue();
		}
	}

	@Test
	void loadResourceAsStreamWhenFilteredOnResourceShouldReturnNotFound() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader(TEST_RESOURCE)) {
			final InputStream loaded = classLoader.getResourceAsStream(TEST_RESOURCE.getPath());
			assertThat(loaded).isNull();
		}
	}

	@Test
	void loadResourceAsStreamWhenNotFilteredShouldLoadResource() throws Exception {
		try (FilteredClassLoader classLoader = new FilteredClassLoader((resourceName) -> false)) {
			final InputStream loaded = classLoader.getResourceAsStream(TEST_RESOURCE.getPath());
			assertThat(loaded).isNotNull();
		}
	}

	@Test
	void publicDefineClassWhenFilteredThrowsException() throws Exception {
		Class<FilteredClassLoaderTests> hiddenClass = FilteredClassLoaderTests.class;
		try (FilteredClassLoader classLoader = new FilteredClassLoader(hiddenClass)) {
			assertThatIllegalArgumentException()
				.isThrownBy(() -> classLoader.publicDefineClass(hiddenClass.getName(), new byte[] {}, null));
		}
	}

}
