/*
 * Copyright 2012-2019 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.boot.autoconfigure.web;

import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.junit.Test;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.boot.autoconfigure.condition.ConditionalOnExpression;
import org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext;
import org.springframework.boot.context.embedded.ConfigurableEmbeddedServletContainer;
import org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizer;
import org.springframework.boot.context.embedded.EmbeddedServletContainerFactory;
import org.springframework.boot.context.embedded.MockEmbeddedServletContainerFactory;
import org.springframework.boot.test.util.EnvironmentTestUtils;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.FrameworkServlet;

import static org.assertj.core.api.Assertions.assertThat;
import static org.mockito.Mockito.verify;

/**
 * Tests for {@link EmbeddedServletContainerAutoConfiguration}.
 *
 * @author Dave Syer
 */
public class EmbeddedServletContainerAutoConfigurationTests {

	private AnnotationConfigEmbeddedWebApplicationContext context;

	@Test
	public void createFromConfigClass() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(BaseConfiguration.class);
		verifyContext();
	}

	@Test
	public void contextAlreadyHasDispatcherServletWithDefaultName() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(DispatcherServletConfiguration.class,
				BaseConfiguration.class);
		verifyContext();
	}

	@Test
	public void contextAlreadyHasDispatcherServlet() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(SpringServletConfiguration.class,
				BaseConfiguration.class);
		verifyContext();
		assertThat(this.context.getBeanNamesForType(DispatcherServlet.class).length).isEqualTo(2);
	}

	@Test
	public void contextAlreadyHasNonDispatcherServlet() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(NonSpringServletConfiguration.class,
				BaseConfiguration.class);
		verifyContext(); // the non default servlet is still registered
		assertThat(this.context.getBeanNamesForType(DispatcherServlet.class).length).isEqualTo(0);
	}

	@Test
	public void contextAlreadyHasNonServlet() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(NonServletConfiguration.class,
				BaseConfiguration.class);
		assertThat(this.context.getBeanNamesForType(DispatcherServlet.class).length).isEqualTo(0);
		assertThat(this.context.getBeanNamesForType(Servlet.class).length).isEqualTo(0);
	}

	@Test
	public void contextAlreadyHasDispatcherServletAndRegistration() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(
				DispatcherServletWithRegistrationConfiguration.class, BaseConfiguration.class);
		verifyContext();
		assertThat(this.context.getBeanNamesForType(DispatcherServlet.class).length).isEqualTo(1);
	}

	@Test
	public void containerHasNoServletContext() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(EnsureContainerHasNoServletContext.class,
				BaseConfiguration.class);
		verifyContext();
	}

	@Test
	public void customizeContainerThroughCallback() throws Exception {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext(CallbackEmbeddedContainerCustomizer.class,
				BaseConfiguration.class);
		verifyContext();
		assertThat(getContainerFactory().getPort()).isEqualTo(9000);
	}

	@Test
	public void initParametersAreConfiguredOnTheServletContext() {
		this.context = new AnnotationConfigEmbeddedWebApplicationContext();
		EnvironmentTestUtils.addEnvironment(this.context, "server.context_parameters.a:alpha",
				"server.context_parameters.b:bravo");
		this.context.register(BaseConfiguration.class);
		this.context.refresh();

		ServletContext servletContext = this.context.getServletContext();
		assertThat(servletContext.getInitParameter("a")).isEqualTo("alpha");
		assertThat(servletContext.getInitParameter("b")).isEqualTo("bravo");
	}

	private void verifyContext() {
		MockEmbeddedServletContainerFactory containerFactory = getContainerFactory();
		Servlet servlet = this.context.getBean(DispatcherServletAutoConfiguration.DEFAULT_DISPATCHER_SERVLET_BEAN_NAME,
				Servlet.class);
		verify(containerFactory.getServletContext()).addServlet("dispatcherServlet", servlet);
	}

	private MockEmbeddedServletContainerFactory getContainerFactory() {
		return this.context.getBean(MockEmbeddedServletContainerFactory.class);
	}

	@Configuration
	@Import({ EmbeddedContainerConfiguration.class, EmbeddedServletContainerAutoConfiguration.class,
			DispatcherServletAutoConfiguration.class, ServerPropertiesAutoConfiguration.class })
	protected static class BaseConfiguration {

	}

	@Configuration
	@ConditionalOnExpression("true")
	public static class EmbeddedContainerConfiguration {

		@Bean
		public EmbeddedServletContainerFactory containerFactory() {
			return new MockEmbeddedServletContainerFactory();
		}

	}

	@Configuration
	public static class DispatcherServletConfiguration {

		@Bean
		public DispatcherServlet dispatcherServlet() {
			return new DispatcherServlet();
		}

	}

	@Configuration
	public static class SpringServletConfiguration {

		@Bean
		public DispatcherServlet springServlet() {
			return new DispatcherServlet();
		}

	}

	@Configuration
	public static class NonSpringServletConfiguration {

		@Bean
		public FrameworkServlet dispatcherServlet() {
			return new FrameworkServlet() {
				@Override
				protected void doService(HttpServletRequest request, HttpServletResponse response) throws Exception {
				}
			};
		}

	}

	@Configuration
	public static class NonServletConfiguration {

		@Bean
		public String dispatcherServlet() {
			return "foo";
		}

	}

	@Configuration
	public static class DispatcherServletWithRegistrationConfiguration {

		@Bean(name = DispatcherServletAutoConfiguration.DEFAULT_DISPATCHER_SERVLET_BEAN_NAME)
		public DispatcherServlet dispatcherServlet() {
			return new DispatcherServlet();
		}

		@Bean(name = DispatcherServletAutoConfiguration.DEFAULT_DISPATCHER_SERVLET_REGISTRATION_BEAN_NAME)
		public ServletRegistrationBean dispatcherRegistration() {
			return new ServletRegistrationBean(dispatcherServlet(), "/app/*");
		}

	}

	@Component
	public static class EnsureContainerHasNoServletContext implements BeanPostProcessor {

		@Override
		public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
			if (bean instanceof ConfigurableEmbeddedServletContainer) {
				MockEmbeddedServletContainerFactory containerFactory = (MockEmbeddedServletContainerFactory) bean;
				assertThat(containerFactory.getServletContext()).isNull();
			}
			return bean;
		}

		@Override
		public Object postProcessAfterInitialization(Object bean, String beanName) {
			return bean;
		}

	}

	@Component
	public static class CallbackEmbeddedContainerCustomizer implements EmbeddedServletContainerCustomizer {

		@Override
		public void customize(ConfigurableEmbeddedServletContainer container) {
			container.setPort(9000);
		}

	}

}
