/*
 * Copyright 2002-2016 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.security.web.authentication.preauth;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.fail;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyZeroInteractions;
import static org.mockito.Mockito.when;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
import org.springframework.mock.web.MockFilterChain;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.authentication.TestingAuthenticationToken;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.authority.AuthorityUtils;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.web.WebAttributes;
import org.springframework.security.web.authentication.ForwardAuthenticationFailureHandler;
import org.springframework.security.web.authentication.ForwardAuthenticationSuccessHandler;

/**
 *
 * @author Rob Winch
 *
 */
public class AbstractPreAuthenticatedProcessingFilterTests {
	private AbstractPreAuthenticatedProcessingFilter filter;

	@Before
	public void createFilter() {
		filter = new AbstractPreAuthenticatedProcessingFilter() {
			protected Object getPreAuthenticatedCredentials(HttpServletRequest request) {
				return "n/a";
			}

			protected Object getPreAuthenticatedPrincipal(HttpServletRequest request) {
				return "doesntmatter";
			}
		};
		SecurityContextHolder.clearContext();
	}

	@After
	public void tearDown() {
		SecurityContextHolder.clearContext();
	}

	@Test
	public void filterChainProceedsOnFailedAuthenticationByDefault() throws Exception {
		AuthenticationManager am = mock(AuthenticationManager.class);
		when(am.authenticate(any(Authentication.class))).thenThrow(
				new BadCredentialsException(""));
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();
		filter.doFilter(new MockHttpServletRequest(), new MockHttpServletResponse(),
				mock(FilterChain.class));
		assertThat(SecurityContextHolder.getContext().getAuthentication()).isNull();
	}

	/* SEC-881 */
	@Test(expected = BadCredentialsException.class)
	public void exceptionIsThrownOnFailedAuthenticationIfContinueFilterChainOnUnsuccessfulAuthenticationSetToFalse()
			throws Exception {
		AuthenticationManager am = mock(AuthenticationManager.class);
		when(am.authenticate(any(Authentication.class))).thenThrow(
				new BadCredentialsException(""));
		filter.setContinueFilterChainOnUnsuccessfulAuthentication(false);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();
		filter.doFilter(new MockHttpServletRequest(), new MockHttpServletResponse(),
				mock(FilterChain.class));
		assertThat(SecurityContextHolder.getContext().getAuthentication()).isNull();
	}

	@Test
	public void testAfterPropertiesSet() {
		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		try {
			filter.afterPropertiesSet();
			fail("AfterPropertiesSet didn't throw expected exception");
		}
		catch (IllegalArgumentException expected) {
		}
		catch (Exception unexpected) {
			fail("AfterPropertiesSet throws unexpected exception");
		}
	}

	// SEC-2045
	@Test
	public void testAfterPropertiesSetInvokesSuper() throws Exception {
		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();
		assertThat(filter.initFilterBeanInvoked).isTrue();
	}

	@Test
	public void testDoFilterAuthenticated() throws Exception {
		testDoFilter(true);
	}

	@Test
	public void testDoFilterUnauthenticated() throws Exception {
		testDoFilter(false);
	}

	// SEC-1968
	@Test
	public void nullPreAuthenticationClearsPreviousUser() throws Exception {
		SecurityContextHolder.getContext().setAuthentication(
				new TestingAuthenticationToken("oldUser", "pass", "ROLE_USER"));
		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.principal = null;
		filter.setCheckForPrincipalChanges(true);

		filter.doFilter(new MockHttpServletRequest(), new MockHttpServletResponse(),
				new MockFilterChain());

		assertThat(SecurityContextHolder.getContext().getAuthentication()).isEqualTo(null);
	}

	@Test
	public void nullPreAuthenticationPerservesPreviousUserCheckPrincipalChangesFalse()
			throws Exception {
		TestingAuthenticationToken authentication = new TestingAuthenticationToken(
				"oldUser", "pass", "ROLE_USER");
		SecurityContextHolder.getContext().setAuthentication(authentication);
		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.principal = null;

		filter.doFilter(new MockHttpServletRequest(), new MockHttpServletResponse(),
				new MockFilterChain());

		assertThat(SecurityContextHolder.getContext().getAuthentication()).isEqualTo(
				authentication);
	}

	@Test
	public void requiresAuthenticationFalsePrincipalString() throws Exception {
		Object principal = "sameprincipal";
		SecurityContextHolder.getContext().setAuthentication(
				new TestingAuthenticationToken(principal, "something", "ROLE_USER"));
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setCheckForPrincipalChanges(true);
		filter.principal = principal;
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verifyZeroInteractions(am);
	}

	@Test
	public void requiresAuthenticationTruePrincipalString() throws Exception {
		Object currentPrincipal = "currentUser";
		TestingAuthenticationToken authRequest = new TestingAuthenticationToken(
				currentPrincipal, "something", "ROLE_USER");
		SecurityContextHolder.getContext().setAuthentication(authRequest);
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setCheckForPrincipalChanges(true);
		filter.principal = "newUser";
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verify(am).authenticate(any(PreAuthenticatedAuthenticationToken.class));
	}

	@Test
	public void callsAuthenticationSuccessHandlerOnSuccessfulAuthentication() throws Exception {
		Object currentPrincipal = "currentUser";
		TestingAuthenticationToken authRequest = new TestingAuthenticationToken(
				currentPrincipal, "something", "ROLE_USER");
		SecurityContextHolder.getContext().setAuthentication(authRequest);
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setAuthenticationSuccessHandler(new ForwardAuthenticationSuccessHandler("/forwardUrl"));
		filter.setCheckForPrincipalChanges(true);
		filter.principal = "newUser";
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verify(am).authenticate(any(PreAuthenticatedAuthenticationToken.class));
		assertThat(response.getForwardedUrl()).isEqualTo("/forwardUrl");
	}

	@Test
	public void callsAuthenticationFailureHandlerOnFailedAuthentication() throws Exception {
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setAuthenticationFailureHandler(new ForwardAuthenticationFailureHandler("/forwardUrl"));
		filter.setCheckForPrincipalChanges(true);
		AuthenticationManager am = mock(AuthenticationManager.class);
		when(am.authenticate(any(PreAuthenticatedAuthenticationToken.class))).thenThrow(new PreAuthenticatedCredentialsNotFoundException("invalid"));
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verify(am).authenticate(any(PreAuthenticatedAuthenticationToken.class));
		assertThat(response.getForwardedUrl()).isEqualTo("/forwardUrl");
		assertThat(request.getAttribute(WebAttributes.AUTHENTICATION_EXCEPTION)).isNotNull();
	}

	// SEC-2078
	@Test
	public void requiresAuthenticationFalsePrincipalNotString() throws Exception {
		Object principal = new Object();
		SecurityContextHolder.getContext().setAuthentication(
				new TestingAuthenticationToken(principal, "something", "ROLE_USER"));
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setCheckForPrincipalChanges(true);
		filter.principal = principal;
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verifyZeroInteractions(am);
	}

	@Test
	public void requiresAuthenticationFalsePrincipalUser() throws Exception {
		User currentPrincipal = new User("user", "password",
				AuthorityUtils.createAuthorityList("ROLE_USER"));
		UsernamePasswordAuthenticationToken currentAuthentication = new UsernamePasswordAuthenticationToken(
				currentPrincipal, currentPrincipal.getPassword(),
				currentPrincipal.getAuthorities());
		SecurityContextHolder.getContext().setAuthentication(currentAuthentication);
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setCheckForPrincipalChanges(true);
		filter.principal = new User(currentPrincipal.getUsername(),
				currentPrincipal.getPassword(), AuthorityUtils.NO_AUTHORITIES);
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verifyZeroInteractions(am);
	}

	@Test
	public void requiresAuthenticationTruePrincipalNotString() throws Exception {
		Object currentPrincipal = new Object();
		TestingAuthenticationToken authRequest = new TestingAuthenticationToken(
				currentPrincipal, "something", "ROLE_USER");
		SecurityContextHolder.getContext().setAuthentication(authRequest);
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		filter.setCheckForPrincipalChanges(true);
		filter.principal = new Object();
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verify(am).authenticate(any(PreAuthenticatedAuthenticationToken.class));
	}

	@Test
	public void requiresAuthenticationOverridePrincipalChangedTrue() throws Exception {
		Object principal = new Object();
		SecurityContextHolder.getContext().setAuthentication(
				new TestingAuthenticationToken(principal, "something", "ROLE_USER"));
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter() {
			@Override
			protected boolean principalChanged(HttpServletRequest request,
					Authentication currentAuthentication) {
				return true;
			}
		};
		filter.setCheckForPrincipalChanges(true);
		filter.principal = principal;
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verify(am).authenticate(any(PreAuthenticatedAuthenticationToken.class));
	}

	@Test
	public void requiresAuthenticationOverridePrincipalChangedFalse() throws Exception {
		Object principal = new Object();
		SecurityContextHolder.getContext().setAuthentication(
				new TestingAuthenticationToken(principal, "something", "ROLE_USER"));
		MockHttpServletRequest request = new MockHttpServletRequest();
		MockHttpServletResponse response = new MockHttpServletResponse();
		MockFilterChain chain = new MockFilterChain();

		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter() {
			@Override
			protected boolean principalChanged(HttpServletRequest request,
					Authentication currentAuthentication) {
				return false;
			}
		};
		filter.setCheckForPrincipalChanges(true);
		filter.principal = principal;
		AuthenticationManager am = mock(AuthenticationManager.class);
		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();

		filter.doFilter(request, response, chain);

		verifyZeroInteractions(am);
	}

	private void testDoFilter(boolean grantAccess) throws Exception {
		MockHttpServletRequest req = new MockHttpServletRequest();
		MockHttpServletResponse res = new MockHttpServletResponse();
		getFilter(grantAccess).doFilter(req, res, new MockFilterChain());
		assertThat(null != SecurityContextHolder.getContext().getAuthentication()).isEqualTo(
				grantAccess);
	}

	private static ConcretePreAuthenticatedProcessingFilter getFilter(boolean grantAccess)
			throws Exception {
		ConcretePreAuthenticatedProcessingFilter filter = new ConcretePreAuthenticatedProcessingFilter();
		AuthenticationManager am = mock(AuthenticationManager.class);

		if (!grantAccess) {
			when(am.authenticate(any(Authentication.class))).thenThrow(
					new BadCredentialsException(""));
		}
		else {
			when(am.authenticate(any(Authentication.class))).thenAnswer(
					new Answer<Authentication>() {
						public Authentication answer(InvocationOnMock invocation)
								throws Throwable {
							return (Authentication) invocation.getArguments()[0];
						}
					});
		}

		filter.setAuthenticationManager(am);
		filter.afterPropertiesSet();
		return filter;
	}

	private static class ConcretePreAuthenticatedProcessingFilter extends
			AbstractPreAuthenticatedProcessingFilter {
		private Object principal = "testPrincipal";
		private boolean initFilterBeanInvoked;

		protected Object getPreAuthenticatedPrincipal(HttpServletRequest httpRequest) {
			return principal;
		}

		protected Object getPreAuthenticatedCredentials(HttpServletRequest httpRequest) {
			return "testCredentials";
		}

		@Override
		protected void initFilterBean() throws ServletException {
			super.initFilterBean();
			initFilterBeanInvoked = true;
		}
	}

}
