// 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.google.gerrit.server.group.db;

import static com.google.common.truth.Truth.assertThat;
import static com.google.gerrit.testing.TestActionRefUpdateContext.testRefAction;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.google.gerrit.entities.Account;
import com.google.gerrit.entities.AccountGroup;
import com.google.gerrit.entities.AccountGroupByIdAudit;
import com.google.gerrit.entities.AccountGroupMemberAudit;
import com.google.gerrit.entities.InternalGroup;
import com.google.gerrit.server.account.GroupUuid;
import com.google.gerrit.server.account.externalids.storage.notedb.DisabledExternalIdCache;
import com.google.gerrit.server.notedb.NoteDbUtil;
import java.time.Instant;
import java.util.Optional;
import java.util.Set;
import org.eclipse.jgit.lib.Config;
import org.eclipse.jgit.lib.PersonIdent;
import org.junit.Before;
import org.junit.Test;

/** Unit tests for {@link AuditLogReader}. */
public final class AuditLogReaderTest extends AbstractGroupTest {

  private AuditLogReader auditLogReader;

  @Before
  public void setUp() throws Exception {
    auditLogReader =
        new AuditLogReader(
            allUsersName, new NoteDbUtil(SERVER_ID, new DisabledExternalIdCache()), new Config());
  }

  @Test
  public void createGroupAsUserIdent() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();

    AccountGroupMemberAudit expAudit =
        createExpMemberAudit(group.getId(), userId, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid)).containsExactly(expAudit);
  }

  @Test
  public void createGroupAsServerIdent() throws Exception {
    InternalGroup group = createGroup(1, "test-group", serverIdent, null);
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, group.getGroupUUID())).isEmpty();
  }

  @Test
  public void addAndRemoveMember() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();

    AccountGroupMemberAudit expAudit1 =
        createExpMemberAudit(group.getId(), userId, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid)).containsExactly(expAudit1);

    // User adds account 100002 to the group.
    Account.Id id = Account.id(100002);
    addMembers(uuid, ImmutableSet.of(id));

    AccountGroupMemberAudit expAudit2 =
        createExpMemberAudit(group.getId(), id, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expAudit1, expAudit2)
        .inOrder();

    // User removes account 100002 from the group.
    removeMembers(uuid, ImmutableSet.of(id));

    expAudit2 = expAudit2.toBuilder().removed(userId, getTipTimestamp(uuid)).build();
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expAudit1, expAudit2)
        .inOrder();
  }

  @Test
  public void addMemberByUnknownAuthorAndRemoveMemberByKnownAuthor() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();
    AccountGroupMemberAudit expAudit1 =
        createExpMemberAudit(group.getId(), userId, userId, getTipTimestamp(uuid));

    // An unidentified user adds account 100002 to the group.
    Account.Id id = Account.id(100002);
    addMembers(
        uuid,
        ImmutableSet.of(id),
        new PersonIdent("Test ident", "random@gerrit"),
        Optional.of(Instant.ofEpochSecond(1)));
    // Identified user removes account 100002 from the group.
    removeMembers(uuid, ImmutableSet.of(id));

    AccountGroupMemberAudit expAudit2 =
        createExpMemberAudit(
                group.getId(), id, Account.UNKNOWN_ACCOUNT_ID, Instant.ofEpochSecond(1))
            .toBuilder()
            .removed(userId, getTipTimestamp(uuid))
            .build();
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expAudit1, expAudit2)
        .inOrder();
  }

  @Test
  public void addMemberByUnknownAuthorAndRemoveMemberByKnownAuthor_ignoreUnidentifiedUser()
      throws Exception {
    // This test doesn't repeat the previous test, because it doesn't produce the correct result.
    // Instead this test adds and removes uses by an unidentified user and expects nothing in the
    // output.
    Config cfg = new Config();
    cfg.setBoolean("groups", "auditLog", "ignoreRecordsFromUnidentifiedUsers", true);
    auditLogReader =
        new AuditLogReader(
            allUsersName, new NoteDbUtil(SERVER_ID, new DisabledExternalIdCache()), cfg);
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();
    AccountGroupMemberAudit expAudit1 =
        createExpMemberAudit(group.getId(), userId, userId, getTipTimestamp(uuid));

    // An unidentified user adds account 100002 to the group.
    Account.Id id = Account.id(100002);
    addMembers(
        uuid,
        ImmutableSet.of(id),
        new PersonIdent("Test ident", "random@gerrit"),
        Optional.of(Instant.ofEpochSecond(1)));
    // Identified user removes account 100002 from the group.
    removeMembers(
        uuid,
        ImmutableSet.of(id),
        new PersonIdent("Test ident", "random@gerrit"),
        Optional.of(Instant.ofEpochSecond(100)));

    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid)).containsExactly(expAudit1);
  }

  @Test
  public void addMultiMembers() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.Id groupId = group.getId();
    AccountGroup.UUID uuid = group.getGroupUUID();

    AccountGroupMemberAudit expAudit1 =
        createExpMemberAudit(groupId, userId, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid)).containsExactly(expAudit1);

    Account.Id id1 = Account.id(100002);
    Account.Id id2 = Account.id(100003);
    addMembers(uuid, ImmutableSet.of(id1, id2));

    AccountGroupMemberAudit expAudit2 =
        createExpMemberAudit(groupId, id1, userId, getTipTimestamp(uuid));
    AccountGroupMemberAudit expAudit3 =
        createExpMemberAudit(groupId, id2, userId, getTipTimestamp(uuid));

    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expAudit1, expAudit2, expAudit3)
        .inOrder();
  }

  @Test
  public void addAndRemoveSubgroups() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();

    InternalGroup subgroup = createGroupAsUser(2, "test-group-2");
    AccountGroup.UUID subgroupUuid = subgroup.getGroupUUID();

    addSubgroups(uuid, ImmutableSet.of(subgroupUuid));

    AccountGroupByIdAudit expAudit =
        createExpGroupAudit(group.getId(), subgroupUuid, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid)).containsExactly(expAudit);

    removeSubgroups(uuid, ImmutableSet.of(subgroupUuid));

    expAudit = expAudit.toBuilder().removed(userId, getTipTimestamp(uuid)).build();
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid)).containsExactly(expAudit);
  }

  @Test
  public void addMultiSubgroups() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.UUID uuid = group.getGroupUUID();

    InternalGroup subgroup1 = createGroupAsUser(2, "test-group-2");
    InternalGroup subgroup2 = createGroupAsUser(3, "test-group-3");
    AccountGroup.UUID subgroupUuid1 = subgroup1.getGroupUUID();
    AccountGroup.UUID subgroupUuid2 = subgroup2.getGroupUUID();

    addSubgroups(uuid, ImmutableSet.of(subgroupUuid1, subgroupUuid2));

    AccountGroupByIdAudit expAudit1 =
        createExpGroupAudit(group.getId(), subgroupUuid1, userId, getTipTimestamp(uuid));
    AccountGroupByIdAudit expAudit2 =
        createExpGroupAudit(group.getId(), subgroupUuid2, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid))
        .containsExactly(expAudit1, expAudit2)
        .inOrder();
  }

  @Test
  public void addAndRemoveMembersAndSubgroups() throws Exception {
    InternalGroup group = createGroupAsUser(1, "test-group");
    AccountGroup.Id groupId = group.getId();
    AccountGroup.UUID uuid = group.getGroupUUID();
    AccountGroupMemberAudit expMemberAudit =
        createExpMemberAudit(groupId, userId, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid)).containsExactly(expMemberAudit);

    Account.Id id1 = Account.id(100002);
    Account.Id id2 = Account.id(100003);
    Account.Id id3 = Account.id(100004);
    InternalGroup subgroup1 = createGroupAsUser(2, "test-group-2");
    InternalGroup subgroup2 = createGroupAsUser(3, "test-group-3");
    InternalGroup subgroup3 = createGroupAsUser(4, "test-group-4");
    AccountGroup.UUID subgroupUuid1 = subgroup1.getGroupUUID();
    AccountGroup.UUID subgroupUuid2 = subgroup2.getGroupUUID();
    AccountGroup.UUID subgroupUuid3 = subgroup3.getGroupUUID();

    // Add two accounts.
    addMembers(uuid, ImmutableSet.of(id1, id2));
    AccountGroupMemberAudit expMemberAudit1 =
        createExpMemberAudit(groupId, id1, userId, getTipTimestamp(uuid));
    AccountGroupMemberAudit expMemberAudit2 =
        createExpMemberAudit(groupId, id2, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expMemberAudit, expMemberAudit1, expMemberAudit2)
        .inOrder();

    // Add one subgroup.
    addSubgroups(uuid, ImmutableSet.of(subgroupUuid1));
    AccountGroupByIdAudit expGroupAudit1 =
        createExpGroupAudit(group.getId(), subgroupUuid1, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid))
        .containsExactly(expGroupAudit1);

    // Remove one account.
    removeMembers(uuid, ImmutableSet.of(id2));
    expMemberAudit2 = expMemberAudit2.toBuilder().removed(userId, getTipTimestamp(uuid)).build();
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(expMemberAudit, expMemberAudit1, expMemberAudit2)
        .inOrder();

    // Add two subgroups.
    addSubgroups(uuid, ImmutableSet.of(subgroupUuid2, subgroupUuid3));
    AccountGroupByIdAudit expGroupAudit2 =
        createExpGroupAudit(group.getId(), subgroupUuid2, userId, getTipTimestamp(uuid));
    AccountGroupByIdAudit expGroupAudit3 =
        createExpGroupAudit(group.getId(), subgroupUuid3, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid))
        .containsExactly(expGroupAudit1, expGroupAudit2, expGroupAudit3)
        .inOrder();

    // Add two account, including a removed account.
    addMembers(uuid, ImmutableSet.of(id2, id3));
    AccountGroupMemberAudit expMemberAudit4 =
        createExpMemberAudit(groupId, id2, userId, getTipTimestamp(uuid));
    AccountGroupMemberAudit expMemberAudit3 =
        createExpMemberAudit(groupId, id3, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getMembersAudit(allUsersRepo, uuid))
        .containsExactly(
            expMemberAudit, expMemberAudit1, expMemberAudit2, expMemberAudit4, expMemberAudit3)
        .inOrder();

    // Remove two subgroups.
    removeSubgroups(uuid, ImmutableSet.of(subgroupUuid1, subgroupUuid3));
    expGroupAudit1 = expGroupAudit1.toBuilder().removed(userId, getTipTimestamp(uuid)).build();
    expGroupAudit3 = expGroupAudit3.toBuilder().removed(userId, getTipTimestamp(uuid)).build();
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid))
        .containsExactly(expGroupAudit1, expGroupAudit2, expGroupAudit3)
        .inOrder();

    // Add back one removed subgroup.
    addSubgroups(uuid, ImmutableSet.of(subgroupUuid1));
    AccountGroupByIdAudit expGroupAudit4 =
        createExpGroupAudit(group.getId(), subgroupUuid1, userId, getTipTimestamp(uuid));
    assertThat(auditLogReader.getSubgroupsAudit(allUsersRepo, uuid))
        .containsExactly(expGroupAudit1, expGroupAudit2, expGroupAudit3, expGroupAudit4)
        .inOrder();
  }

  private InternalGroup createGroupAsUser(int next, String groupName) throws Exception {
    return createGroup(next, groupName, userIdent, userId);
  }

  private InternalGroup createGroup(
      int next, String groupName, PersonIdent authorIdent, Account.Id authorId) throws Exception {
    return testRefAction(
        () -> {
          InternalGroupCreation groupCreation =
              InternalGroupCreation.builder()
                  .setGroupUUID(GroupUuid.make(groupName, serverIdent))
                  .setNameKey(AccountGroup.nameKey(groupName))
                  .setId(AccountGroup.id(next))
                  .build();
          GroupDelta groupDelta =
              authorIdent.equals(serverIdent)
                  ? GroupDelta.builder().setDescription("Groups").build()
                  : GroupDelta.builder()
                      .setDescription("Groups")
                      .setMemberModification(members -> ImmutableSet.of(authorId))
                      .build();

          GroupConfig groupConfig =
              GroupConfig.createForNewGroup(allUsersName, allUsersRepo, groupCreation);
          groupConfig.setGroupDelta(groupDelta, getAuditLogFormatter());

          groupConfig.commit(createMetaDataUpdate(authorIdent));
          return groupConfig
              .getLoadedGroup()
              .orElseThrow(() -> new IllegalStateException("create group failed"));
        });
  }

  private void updateGroup(AccountGroup.UUID uuid, GroupDelta groupDelta) throws Exception {
    updateGroup(uuid, groupDelta, userIdent);
  }

  private void updateGroup(AccountGroup.UUID uuid, GroupDelta groupDelta, PersonIdent authorIdent)
      throws Exception {
    testRefAction(
        () -> {
          GroupConfig groupConfig = GroupConfig.loadForGroup(allUsersName, allUsersRepo, uuid);
          groupConfig.setGroupDelta(groupDelta, getAuditLogFormatter());
          groupConfig.commit(createMetaDataUpdate(authorIdent));
        });
  }

  private void addMembers(AccountGroup.UUID groupUuid, Set<Account.Id> ids) throws Exception {
    addMembers(groupUuid, ids, userIdent, Optional.empty());
  }

  private void addMembers(
      AccountGroup.UUID groupUuid,
      Set<Account.Id> ids,
      PersonIdent authorIdent,
      Optional<Instant> updatedOn)
      throws Exception {
    GroupDelta.Builder groupDelta =
        GroupDelta.builder().setMemberModification(memberIds -> Sets.union(memberIds, ids));
    if (updatedOn.isPresent()) {
      groupDelta.setUpdatedOn(updatedOn.get());
    }
    updateGroup(groupUuid, groupDelta.build(), authorIdent);
  }

  private void removeMembers(AccountGroup.UUID groupUuid, Set<Account.Id> ids) throws Exception {
    removeMembers(groupUuid, ids, userIdent, Optional.empty());
  }

  private void removeMembers(
      AccountGroup.UUID groupUuid,
      Set<Account.Id> ids,
      PersonIdent authorIdent,
      Optional<Instant> updatedOn)
      throws Exception {
    GroupDelta.Builder groupDelta =
        GroupDelta.builder().setMemberModification(memberIds -> Sets.difference(memberIds, ids));
    if (updatedOn.isPresent()) {
      groupDelta.setUpdatedOn(updatedOn.get());
    }
    updateGroup(groupUuid, groupDelta.build(), authorIdent);
  }

  private void addSubgroups(AccountGroup.UUID groupUuid, Set<AccountGroup.UUID> uuids)
      throws Exception {
    GroupDelta groupDelta =
        GroupDelta.builder()
            .setSubgroupModification(memberIds -> Sets.union(memberIds, uuids))
            .build();
    updateGroup(groupUuid, groupDelta);
  }

  private void removeSubgroups(AccountGroup.UUID groupUuid, Set<AccountGroup.UUID> uuids)
      throws Exception {
    GroupDelta groupDelta =
        GroupDelta.builder()
            .setSubgroupModification(memberIds -> Sets.difference(memberIds, uuids))
            .build();
    updateGroup(groupUuid, groupDelta);
  }

  private static AccountGroupMemberAudit createExpMemberAudit(
      AccountGroup.Id groupId, Account.Id id, Account.Id addedBy, Instant addedOn) {
    return AccountGroupMemberAudit.builder()
        .groupId(groupId)
        .memberId(id)
        .addedOn(addedOn)
        .addedBy(addedBy)
        .build();
  }

  private static AccountGroupByIdAudit createExpGroupAudit(
      AccountGroup.Id groupId, AccountGroup.UUID uuid, Account.Id addedBy, Instant addedOn) {
    return AccountGroupByIdAudit.builder()
        .groupId(groupId)
        .includeUuid(uuid)
        .addedOn(addedOn)
        .addedBy(addedBy)
        .build();
  }
}