/*
 * Copyright 2002-2017 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.test.web.servlet.htmlunit.webdriver;

import com.gargoylesoftware.htmlunit.BrowserVersion;
import com.gargoylesoftware.htmlunit.WebClient;
import org.openqa.selenium.htmlunit.HtmlUnitDriver;

import org.springframework.lang.Nullable;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.htmlunit.MockMvcWebConnectionBuilderSupport;
import org.springframework.test.web.servlet.htmlunit.WebRequestMatcher;
import org.springframework.test.web.servlet.setup.MockMvcConfigurer;
import org.springframework.util.Assert;
import org.springframework.web.context.WebApplicationContext;

/**
 * {@code MockMvcHtmlUnitDriverBuilder} simplifies the building of an
 * {@link HtmlUnitDriver} that delegates to {@link MockMvc} and optionally
 * delegates to an actual connection for specific requests.
 *
 * <p>By default, the driver will delegate to {@code MockMvc} to handle
 * requests to {@code localhost} and to a {@link WebClient} to handle any
 * other URL (i.e. to perform an actual HTTP request).
 *
 * @author Rob Winch
 * @author Sam Brannen
 * @since 4.2
 * @see #mockMvcSetup(MockMvc)
 * @see #webAppContextSetup(WebApplicationContext)
 * @see #webAppContextSetup(WebApplicationContext, MockMvcConfigurer)
 * @see #javascriptEnabled(boolean)
 * @see #withDelegate(WebConnectionHtmlUnitDriver)
 * @see #build()
 */
public class MockMvcHtmlUnitDriverBuilder extends MockMvcWebConnectionBuilderSupport<MockMvcHtmlUnitDriverBuilder> {

	@Nullable
	private HtmlUnitDriver driver;

	private boolean javascriptEnabled = true;


	protected MockMvcHtmlUnitDriverBuilder(MockMvc mockMvc) {
		super(mockMvc);
	}

	protected MockMvcHtmlUnitDriverBuilder(WebApplicationContext context) {
		super(context);
	}

	protected MockMvcHtmlUnitDriverBuilder(WebApplicationContext context, MockMvcConfigurer configurer) {
		super(context, configurer);
	}


	/**
	 * Create a new {@code MockMvcHtmlUnitDriverBuilder} based on the supplied
	 * {@link MockMvc} instance.
	 * @param mockMvc the {@code MockMvc} instance to use (never {@code null})
	 * @return the MockMvcHtmlUnitDriverBuilder to customize
	 */
	public static MockMvcHtmlUnitDriverBuilder mockMvcSetup(MockMvc mockMvc) {
		Assert.notNull(mockMvc, "MockMvc must not be null");
		return new MockMvcHtmlUnitDriverBuilder(mockMvc);
	}

	/**
	 * Create a new {@code MockMvcHtmlUnitDriverBuilder} based on the supplied
	 * {@link WebApplicationContext}.
	 * @param context the {@code WebApplicationContext} to create a {@link MockMvc}
	 * instance from (never {@code null})
	 * @return the MockMvcHtmlUnitDriverBuilder to customize
	 */
	public static MockMvcHtmlUnitDriverBuilder webAppContextSetup(WebApplicationContext context) {
		Assert.notNull(context, "WebApplicationContext must not be null");
		return new MockMvcHtmlUnitDriverBuilder(context);
	}

	/**
	 * Create a new {@code MockMvcHtmlUnitDriverBuilder} based on the supplied
	 * {@link WebApplicationContext} and {@link MockMvcConfigurer}.
	 * @param context the {@code WebApplicationContext} to create a {@link MockMvc}
	 * instance from (never {@code null})
	 * @param configurer the {@code MockMvcConfigurer} to apply (never {@code null})
	 * @return the MockMvcHtmlUnitDriverBuilder to customize
	 */
	public static MockMvcHtmlUnitDriverBuilder webAppContextSetup(WebApplicationContext context,
			MockMvcConfigurer configurer) {

		Assert.notNull(context, "WebApplicationContext must not be null");
		Assert.notNull(configurer, "MockMvcConfigurer must not be null");
		return new MockMvcHtmlUnitDriverBuilder(context, configurer);
	}

	/**
	 * Specify whether JavaScript should be enabled.
	 * <p>Default is {@code true}.
	 * @param javascriptEnabled {@code true} if JavaScript should be enabled
	 * @return this builder for further customizations
	 * @see #build()
	 */
	public MockMvcHtmlUnitDriverBuilder javascriptEnabled(boolean javascriptEnabled) {
		this.javascriptEnabled = javascriptEnabled;
		return this;
	}

	/**
	 * Supply the {@code WebConnectionHtmlUnitDriver} that the driver
	 * {@linkplain #build built} by this builder should delegate to when
	 * processing non-{@linkplain WebRequestMatcher matching} requests.
	 * @param driver the {@code WebConnectionHtmlUnitDriver} to delegate to
	 * for requests that do not match (never {@code null})
	 * @return this builder for further customizations
	 * @see #build()
	 */
	public MockMvcHtmlUnitDriverBuilder withDelegate(WebConnectionHtmlUnitDriver driver) {
		Assert.notNull(driver, "HtmlUnitDriver must not be null");
		driver.setJavascriptEnabled(this.javascriptEnabled);
		driver.setWebConnection(createConnection(driver.getWebClient()));
		this.driver = driver;
		return this;
	}

	/**
	 * Build the {@link HtmlUnitDriver} configured via this builder.
	 * <p>The returned driver will use the configured {@link MockMvc} instance
	 * for processing any {@linkplain WebRequestMatcher matching} requests
	 * and a delegate {@code HtmlUnitDriver} for all other requests.
	 * <p>If a {@linkplain #withDelegate delegate} has been explicitly configured,
	 * it will be used; otherwise, a default {@code WebConnectionHtmlUnitDriver}
	 * with the {@link BrowserVersion} set to {@link BrowserVersion#CHROME CHROME}
	 * will be configured as the delegate.
	 * @return the {@code HtmlUnitDriver} to use
	 * @see #withDelegate(WebConnectionHtmlUnitDriver)
	 */
	public HtmlUnitDriver build() {
		return (this.driver != null ? this.driver :
				withDelegate(new WebConnectionHtmlUnitDriver(BrowserVersion.CHROME)).build());
	}

}
