// Copyright (C) 2017 The Android Open Source Project
//
// 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 com.ericsson.gerrit.plugins.goimport;

import static com.ericsson.gerrit.plugins.goimport.GoImportFilter.CONTENT_PLH;
import static com.ericsson.gerrit.plugins.goimport.GoImportFilter.PAGE_200;
import static com.google.common.truth.Truth.assertThat;
import static com.google.gerrit.testing.GerritJUnit.assertThrows;
import static org.mockito.Mockito.any;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

import com.google.gerrit.entities.Project;
import com.google.gerrit.server.AnonymousUser;
import com.google.gerrit.server.permissions.PermissionBackend;
import com.google.gerrit.server.permissions.RefPermission;
import com.google.gerrit.server.project.ProjectCache;
import com.google.gerrit.server.project.ProjectState;
import com.google.inject.Provider;
import java.io.IOException;
import java.net.URISyntaxException;
import java.util.Optional;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;

@RunWith(MockitoJUnitRunner.class)
public class GoImportFilterTest {
  private static final String PROD_FQDN = "gerrit-review.googlesource.com";
  private static final String PROD_URL = "https://" + PROD_FQDN;
  private static final String PROJECT_NAME = "projectName";
  private static final String CONTENT_FORMAT = "%1$s/%3$s git %2$s/%3$s";
  private static final String CONTENT =
      String.format(CONTENT_FORMAT, PROD_FQDN, auth(PROD_URL), PROJECT_NAME);
  private static final String ANON_CONTENT =
      String.format(CONTENT_FORMAT, PROD_FQDN, PROD_URL, PROJECT_NAME);
  private static final String AUTH_CONTENT =
      String.format(CONTENT_FORMAT, auth(PROD_FQDN), auth(PROD_URL), PROJECT_NAME);

  /** URLs that require authentication has an additional "/a" ($BASE/a/$ENDPOINT). */
  private static String auth(String baseUrl) {
    return baseUrl + "/a";
  }

  private static byte[] response200(boolean allowAnon, boolean authenticated) {
    if (authenticated) {
      return PAGE_200.replace(CONTENT_PLH, AUTH_CONTENT).getBytes();
    } else if (allowAnon) {
      return PAGE_200.replace(CONTENT_PLH, ANON_CONTENT).getBytes();
    }
    return PAGE_200.replace(CONTENT_PLH, CONTENT).getBytes();
  }

  private GoImportFilter unitUnderTest;

  @Mock private Provider<AnonymousUser> mockAnonProvider;
  @Mock private AnonymousUser mockAnon;
  @Mock private PermissionBackend mockPerms;
  @Mock private PermissionBackend.WithUser mockPermsWithUser;
  @Mock private PermissionBackend.ForRef mockPermsForRef;
  @Mock private ProjectCache mockProjectCache;
  @Mock private HttpServletRequest mockRequest;
  @Mock private HttpServletResponse mockResponse;
  @Mock private FilterChain mockChain;
  @Mock private ServletOutputStream mockOutputStream;
  @Mock private ProjectState mockProjectState;

  @Before
  public void setUp() throws Exception {
    unitUnderTest = new GoImportFilter(mockAnonProvider, mockPerms, mockProjectCache, PROD_URL);
    assertThat(unitUnderTest).isNotNull();
    when(mockResponse.getOutputStream()).thenReturn(mockOutputStream);
    when(mockAnonProvider.get()).thenReturn(mockAnon);
    when(mockPerms.user(mockAnon)).thenReturn(mockPermsWithUser);
    when(mockPermsWithUser.ref(any())).thenReturn(mockPermsForRef);
  }

  @Test
  public void testConstructor() throws Exception {
    assertThat(unitUnderTest.webUrl.endsWith("/")).isTrue();
    unitUnderTest =
        new GoImportFilter(
            mockAnonProvider,
            mockPerms,
            mockProjectCache,
            "http://gerrit-review.googlesource.com:8080/");
    assertThat(unitUnderTest.webUrl.endsWith("/")).isTrue();
    assertThat(unitUnderTest.projectPrefix).isNotNull();
  }

  @Test(expected = URISyntaxException.class)
  public void testConstructorWithURISyntaxException() throws Exception {
    unitUnderTest = new GoImportFilter(mockAnonProvider, mockPerms, mockProjectCache, "\\\\");
  }

  @Test
  public void testDoFilterWithNull() throws Exception {
    unitUnderTest.doFilter(null, null, mockChain);
    verify(mockChain, times(1)).doFilter(null, null);
  }

  @Test
  public void testDoFilterWithoutGoGetParameter() throws Exception {
    when(mockRequest.getParameter("go-get")).thenReturn(null);
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(0)).write(any(byte[].class));
    verify(mockChain, times(1)).doFilter(mockRequest, mockResponse);
  }

  @Test
  public void testDoFilterWithWrongGoGetParameterValue() throws Exception {
    when(mockRequest.getParameter("go-get")).thenReturn("2");
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(0)).write(any(byte[].class));
    verify(mockChain, times(1)).doFilter(mockRequest, mockResponse);
  }

  @Test
  public void testDoFilterWithExistingProject() throws Exception {
    when(mockRequest.getServletPath()).thenReturn("/" + PROJECT_NAME);
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    when(mockProjectCache.get(Project.nameKey(PROJECT_NAME)))
        .thenReturn(Optional.of(mockProjectState));
    when(mockPermsForRef.testOrFalse(RefPermission.READ)).thenReturn(false);
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(1)).write(response200(false, false));
    verify(mockChain, times(0)).doFilter(mockRequest, mockResponse);
    verify(mockProjectCache, times(1)).get(any(Project.NameKey.class));
    verify(mockResponse, times(1)).setStatus(200);
    verify(mockPermsForRef, times(1)).testOrFalse(RefPermission.READ);
  }

  @Test
  public void testDoFilterAuthenticatedWithExistingProject() throws Exception {
    when(mockRequest.getServletPath()).thenReturn("/a/" + PROJECT_NAME);
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    when(mockProjectCache.get(Project.nameKey(PROJECT_NAME)))
        .thenReturn(Optional.of(mockProjectState));
    when(mockPermsForRef.testOrFalse(RefPermission.READ)).thenReturn(false);
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(1)).write(response200(false, true));
    verify(mockChain, times(0)).doFilter(mockRequest, mockResponse);
    verify(mockProjectCache, times(1)).get(any(Project.NameKey.class));
    verify(mockResponse, times(1)).setStatus(200);
    verify(mockPermsForRef, times(1)).testOrFalse(RefPermission.READ);
  }

  @Test
  public void testDoFilterWithExistingProjectAndPackage() throws Exception {
    when(mockRequest.getServletPath()).thenReturn("/" + PROJECT_NAME + "/my/package");
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    when(mockProjectCache.get(Project.nameKey(PROJECT_NAME)))
        .thenReturn(Optional.of(mockProjectState));
    when(mockPermsForRef.testOrFalse(RefPermission.READ)).thenReturn(false);
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(1)).write(response200(false, false));
    verify(mockChain, times(0)).doFilter(mockRequest, mockResponse);
    verify(mockProjectCache, times(3)).get(any(Project.NameKey.class));
    verify(mockResponse, times(1)).setStatus(200);
  }

  @Test
  public void testDoFilterWithAnonymousAccessibleProject() throws Exception {
    when(mockRequest.getServletPath()).thenReturn("/projectName");
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    when(mockProjectCache.get(Project.nameKey(PROJECT_NAME)))
        .thenReturn(Optional.of(mockProjectState));
    when(mockPermsForRef.testOrFalse(RefPermission.READ)).thenReturn(true);
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(1)).write(response200(true, false));
    verify(mockChain, times(0)).doFilter(mockRequest, mockResponse);
    verify(mockProjectCache, times(1)).get(any(Project.NameKey.class));
    verify(mockResponse, times(1)).setStatus(200);
    verify(mockPermsForRef, times(1)).testOrFalse(RefPermission.READ);
  }

  @Test
  public void testDoFilterWithNonExistingProject() throws Exception {
    when(mockRequest.getServletPath()).thenReturn("/" + PROJECT_NAME);
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    when(mockProjectCache.get(any(Project.NameKey.class))).thenReturn(Optional.empty());
    unitUnderTest.doFilter(mockRequest, mockResponse, mockChain);
    verify(mockOutputStream, times(1)).write(any(byte[].class));
    verify(mockChain, times(0)).doFilter(mockRequest, mockResponse);
    verify(mockProjectCache, times(1)).get(any(Project.NameKey.class));
    verify(mockResponse, times(1)).setStatus(404);
  }

  @Test
  public void testDoFilterWithIOException() throws Exception {
    String msg = "test-io-error";
    when(mockRequest.getServletPath()).thenReturn("/" + PROJECT_NAME);
    when(mockRequest.getParameter("go-get")).thenReturn("1");
    doThrow(new IOException(msg)).when(mockOutputStream).write(any(byte[].class));
    when(mockProjectCache.get(any(Project.NameKey.class)))
        .thenReturn(Optional.of(mockProjectState));
    IOException thrown =
        assertThrows(
            IOException.class, () -> unitUnderTest.doFilter(mockRequest, mockResponse, mockChain));
    assertThat(thrown).hasMessageThat().isEqualTo(msg);
    verify(mockOutputStream, times(1)).write(any(byte[].class));
  }

  @Test
  public void testDoFilterWithServletException() throws Exception {
    String msg = "test-serv-error";
    doThrow(new ServletException(msg)).when(mockChain).doFilter(null, null);
    ServletException thrown =
        assertThrows(ServletException.class, () -> unitUnderTest.doFilter(null, null, mockChain));
    assertThat(thrown).hasMessageThat().isEqualTo(msg);
    verify(mockChain, times(1)).doFilter(null, null);
  }
}