/*
 * Copyright 2012-2016 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.boot.test.mock.mockito;

import java.util.List;

import org.mockito.MockSettings;
import org.mockito.Mockito;
import org.mockito.internal.util.MockUtil;
import org.mockito.listeners.InvocationListener;
import org.mockito.listeners.MethodInvocationReport;
import org.mockito.mock.MockCreationSettings;

import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;

/**
 * Reset strategy used on a mock bean. Usually applied to a mock via the
 * {@link MockBean @MockBean} annotation but can also be directly applied to any mock in
 * the {@code ApplicationContext} using the static methods.
 *
 * @author Phillip Webb
 * @since 1.4.0
 * @see ResetMocksTestExecutionListener
 */
public enum MockReset {

	/**
	 * Reset the mock before the test method runs.
	 */
	BEFORE,

	/**
	 * Reset the mock after the test method runs.
	 */
	AFTER,

	/**
	 * Don't reset the mock.
	 */
	NONE;

	/**
	 * Create {@link MockSettings settings} to be used with mocks where reset should occur
	 * before each test method runs.
	 * @return mock settings
	 */
	public static MockSettings before() {
		return withSettings(BEFORE);
	}

	/**
	 * Create {@link MockSettings settings} to be used with mocks where reset should occur
	 * after each test method runs.
	 * @return mock settings
	 */
	public static MockSettings after() {
		return withSettings(AFTER);
	}

	/**
	 * Create {@link MockSettings settings} to be used with mocks where a specific reset
	 * should occur.
	 * @param reset the reset type
	 * @return mock settings
	 */
	public static MockSettings withSettings(MockReset reset) {
		return apply(reset, Mockito.withSettings());
	}

	/**
	 * Apply {@link MockReset} to existing {@link MockSettings settings}.
	 * @param reset the reset type
	 * @param settings the settings
	 * @return the configured settings
	 */
	public static MockSettings apply(MockReset reset, MockSettings settings) {
		Assert.notNull(settings, "Settings must not be null");
		if (reset != null && reset != NONE) {
			settings.invocationListeners(new ResetInvocationListener(reset));
		}
		return settings;
	}

	/**
	 * Get the {@link MockReset} associated with the given mock.
	 * @param mock the source mock
	 * @return the reset type (never {@code null})
	 */
	@SuppressWarnings("rawtypes")
	static MockReset get(Object mock) {
		MockReset reset = MockReset.NONE;
		if (ClassUtils.isPresent("org.mockito.internal.util.MockUtil", null)) {
			MockUtil mockUtil = new MockUtil();
			if (mockUtil.isMock(mock)) {
				MockCreationSettings settings = mockUtil.getMockSettings(mock);
				List listeners = settings.getInvocationListeners();
				for (Object listener : listeners) {
					if (listener instanceof ResetInvocationListener) {
						reset = ((ResetInvocationListener) listener).getReset();
					}
				}
			}
		}
		return reset;
	}

	/**
	 * Dummy {@link InvocationListener} used to hold the {@link MockReset} value.
	 */
	private static class ResetInvocationListener implements InvocationListener {

		private final MockReset reset;

		ResetInvocationListener(MockReset reset) {
			this.reset = reset;
		}

		public MockReset getReset() {
			return this.reset;
		}

		@Override
		public void reportInvocation(MethodInvocationReport methodInvocationReport) {
		}

	}

}
