// Copyright (C) 2022 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.googlesource.gerrit.owners.restapi;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.collect.ImmutableMap;
import com.google.gerrit.acceptance.GitUtil;
import com.google.gerrit.acceptance.LightweightPluginDaemonTest;
import com.google.gerrit.acceptance.PushOneCommit.Result;
import com.google.gerrit.acceptance.TestPlugin;
import com.google.gerrit.acceptance.UseLocalDisk;
import com.google.gerrit.acceptance.config.GlobalPluginConfig;
import com.google.gerrit.entities.Project;
import com.google.gerrit.entities.Project.NameKey;
import com.google.gerrit.entities.RefNames;
import com.google.gerrit.extensions.client.SubmitType;
import com.google.gerrit.extensions.restapi.AuthException;
import com.google.gerrit.extensions.restapi.BadRequestException;
import com.google.gerrit.extensions.restapi.ResourceConflictException;
import com.google.gerrit.extensions.restapi.Response;
import com.googlesource.gerrit.owners.entities.FilesOwnersResponse;
import com.googlesource.gerrit.owners.entities.GroupOwner;
import com.googlesource.gerrit.owners.entities.Owner;
import java.util.Arrays;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.compress.utils.Sets;
import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
import org.eclipse.jgit.junit.TestRepository;
import org.eclipse.jgit.lib.Config;
import org.eclipse.jgit.transport.FetchResult;
import org.eclipse.jgit.util.FS;
import org.junit.Test;

@TestPlugin(name = "owners", httpModule = "com.googlesource.gerrit.owners.OwnersRestApiModule")
@UseLocalDisk
public class GetFilesOwnersIT extends LightweightPluginDaemonTest {

  private static final String REFS_META_CONFIG = RefNames.REFS_META + "config";
  private GetFilesOwners ownersApi;
  private Owner rootOwner;
  private Owner projectOwner;
  private NameKey parentProjectName;
  private NameKey childProjectName;
  private TestRepository<InMemoryRepository> childRepo;
  private TestRepository<InMemoryRepository> parentRepo;
  private TestRepository<InMemoryRepository> allProjectsRepo;

  @Override
  public void setUpTestPlugin() throws Exception {
    super.setUpTestPlugin();

    rootOwner = new Owner(admin.fullName(), admin.id().get());
    projectOwner = new Owner(user.fullName(), user.id().get());
    ownersApi = plugin.getSysInjector().getInstance(GetFilesOwners.class);

    parentProjectName =
        createProjectOverAPI("parent", allProjects, true, SubmitType.FAST_FORWARD_ONLY);
    parentRepo = cloneProjectWithMetaRefs(parentProjectName);

    childProjectName =
        createProjectOverAPI("child", parentProjectName, true, SubmitType.FAST_FORWARD_ONLY);
    childRepo = cloneProject(childProjectName);

    allProjectsRepo = cloneProjectWithMetaRefs(allProjects);
  }

  @Test
  public void shouldReturnExactFileOwners() throws Exception {
    addOwnerFileToRoot(true);
    assertChangeHasOwners(createChange().getChangeId());
  }

  @Test
  public void shouldReturnExactFileOwnersWhenOwnersIsSetToAllProjects() throws Exception {
    addOwnerFileWithMatchers(allProjectsRepo, REFS_META_CONFIG, true);
    assertChangeHasOwners(createChange(childRepo).getChangeId());
  }

  @Test
  public void shouldReturnExactFileOwnersWhenOwnersIsSetToParentProject() throws Exception {
    addOwnerFileWithMatchers(parentRepo, REFS_META_CONFIG, true);
    assertChangeHasOwners(createChange(childRepo).getChangeId());
  }

  @Test
  public void shouldReturnOwnersLabels() throws Exception {
    addOwnerFileToRoot(true);
    String changeId = createChange().getChangeId();
    approve(changeId);

    Response<FilesOwnersResponse> resp =
        assertResponseOk(ownersApi.apply(parseCurrentRevisionResource(changeId)));

    assertThat(resp.value().ownersLabels)
        .containsExactly(admin.id().get(), ImmutableMap.builder().put("Code-Review", 2).build());
  }

  @Test
  @GlobalPluginConfig(pluginName = "owners", name = "owners.expandGroups", value = "false")
  public void shouldReturnResponseWithUnexpandedFileOwners() throws Exception {
    addOwnerFileToRoot(true);
    String changeId = createChange().getChangeId();

    Response<FilesOwnersResponse> resp =
        assertResponseOk(ownersApi.apply(parseCurrentRevisionResource(changeId)));

    assertThat(resp.value().files)
        .containsExactly("a.txt", Sets.newHashSet(new GroupOwner(admin.username())));
  }

  @Test
  @GlobalPluginConfig(pluginName = "owners", name = "owners.expandGroups", value = "false")
  public void shouldReturnResponseWithUnexpandedFileMatchersOwners() throws Exception {
    addOwnerFileWithMatchersToRoot(true);
    String changeId = createChange().getChangeId();

    Response<FilesOwnersResponse> resp =
        assertResponseOk(ownersApi.apply(parseCurrentRevisionResource(changeId)));

    assertThat(resp.value().files)
        .containsExactly("a.txt", Sets.newHashSet(new GroupOwner(admin.username())));
  }

  @Test
  @UseLocalDisk
  public void shouldReturnInheritedOwnersFromProjectsOwners() throws Exception {
    assertInheritFromProject(project);
  }

  @Test
  @UseLocalDisk
  public void shouldReturnInheritedOwnersFromParentProjectsOwners() throws Exception {
    assertInheritFromProject(allProjects);
  }

  @Test
  @UseLocalDisk
  public void shouldNotReturnInheritedOwnersFromProjectsOwners() throws Exception {
    assertNotInheritFromProject(project);
  }

  @Test
  @UseLocalDisk
  public void shouldNotReturnInheritedOwnersFromParentProjectsOwners() throws Exception {
    addOwnerFileToProjectConfig(project, false);
    assertNotInheritFromProject(allProjects);
  }

  private static <T> Response<T> assertResponseOk(Response<T> response) {
    assertThat(response.statusCode()).isEqualTo(HttpServletResponse.SC_OK);
    return response;
  }

  private void assertNotInheritFromProject(Project.NameKey projectNameKey) throws Exception {
    addOwnerFileToRoot(false);
    addOwnerFileToProjectConfig(projectNameKey, true);

    String changeId = createChange().getChangeId();
    assertChangeHasOwners(changeId);
  }

  private void assertChangeHasOwners(String changeId)
      throws AuthException, BadRequestException, ResourceConflictException, Exception {
    Response<FilesOwnersResponse> resp =
        assertResponseOk(ownersApi.apply(parseCurrentRevisionResource(changeId)));

    assertThat(resp.value().files).containsExactly("a.txt", Sets.newHashSet(rootOwner));
  }

  private void assertInheritFromProject(Project.NameKey projectNameKey) throws Exception {
    addOwnerFileToRoot(true);
    addOwnerFileToProjectConfig(projectNameKey, true);

    String changeId = createChange().getChangeId();
    Response<FilesOwnersResponse> resp =
        assertResponseOk(ownersApi.apply(parseCurrentRevisionResource(changeId)));

    assertThat(resp.value().files)
        .containsExactly("a.txt", Sets.newHashSet(rootOwner, projectOwner));
  }

  private void addOwnerFileToProjectConfig(Project.NameKey projectNameKey, boolean inherit)
      throws Exception {
    TestRepository<InMemoryRepository> project = cloneProject(projectNameKey);
    GitUtil.fetch(project, RefNames.REFS_CONFIG + ":" + RefNames.REFS_CONFIG);
    project.reset(RefNames.REFS_CONFIG);
    pushFactory
        .create(
            admin.newIdent(),
            project,
            "Add OWNER file",
            "OWNERS",
            String.format(
                "inherited: %s\nmatchers:\n" + "- suffix: .txt\n  owners:\n   - %s\n",
                inherit, user.email()))
        .to(RefNames.REFS_CONFIG);
  }

  private void addOwnerFileToRoot(boolean inherit) throws Exception {
    // Add OWNERS file to root:
    //
    // inherited: true
    // owners:
    // - admin
    merge(
        createChange(
            testRepo,
            "master",
            "Add OWNER file",
            "OWNERS",
            String.format("inherited: %s\nowners:\n- %s\n", inherit, admin.email()),
            ""));
  }

  private void addOwnerFileWithMatchersToRoot(boolean inherit) throws Exception {
    addOwnerFileWithMatchers(testRepo, "master", inherit);
  }

  private void addOwnerFileWithMatchers(TestRepository<?> repo, String targetRef, boolean inherit)
      throws Exception {
    // Add OWNERS file to root:
    //
    // inherited: true
    // matchers:
    // - suffix: .txt
    //   owners:
    //   - admin@mail.com
    Result changeCreated =
        createChange(
            repo,
            targetRef,
            "Add OWNER file",
            "OWNERS",
            String.format(
                "inherited: %s\nmatchers:\n" + "- suffix: .txt\n  owners:\n   - %s\n",
                inherit, admin.email()),
            "");
    changeCreated.assertOkStatus();
    merge(changeCreated);
  }

  public TestRepository<InMemoryRepository> cloneProjectWithMetaRefs(Project.NameKey project)
      throws Exception {
    String uri = registerRepoConnection(project, admin);
    String initialRef = "refs/remotes/origin/config";
    DfsRepositoryDescription desc = new DfsRepositoryDescription("clone of " + project.get());

    InMemoryRepository.Builder b = new InMemoryRepository.Builder().setRepositoryDescription(desc);
    if (uri.startsWith("ssh://")) {
      // SshTransport depends on a real FS to read ~/.ssh/config, but InMemoryRepository by default
      // uses a null FS.
      // Avoid leaking user state into our tests.
      b.setFS(FS.detect().setUserHome(null));
    }
    InMemoryRepository dest = b.build();
    Config cfg = dest.getConfig();
    cfg.setString("remote", "origin", "url", uri);
    cfg.setStringList(
        "remote",
        "origin",
        "fetch",
        Arrays.asList(
            "+refs/heads/*:refs/remotes/origin/*", "+refs/meta/config:refs/remotes/origin/config"));
    TestRepository<InMemoryRepository> testRepo = GitUtil.newTestRepository(dest);
    FetchResult result = testRepo.git().fetch().setRemote("origin").call();
    if (result.getTrackingRefUpdate(initialRef) != null) {
      testRepo.reset(initialRef);
    }
    return testRepo;
  }
}