// Copyright (C) 2018 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.acceptance.rest;

import static com.google.common.truth.Truth.assertThat;
import static org.apache.http.HttpStatus.SC_CREATED;

import com.google.auto.value.AutoValue;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.truth.Expect;
import com.google.gerrit.acceptance.AbstractDaemonTest;
import com.google.gerrit.acceptance.PushOneCommit;
import com.google.gerrit.acceptance.RestResponse;
import com.google.gerrit.extensions.registration.DynamicSet;
import com.google.gerrit.extensions.registration.RegistrationHandle;
import com.google.gerrit.httpd.restapi.ParameterParser;
import com.google.gerrit.httpd.restapi.RestApiServlet;
import com.google.gerrit.server.events.CommitReceivedEvent;
import com.google.gerrit.server.git.WorkQueue;
import com.google.gerrit.server.git.validators.CommitValidationException;
import com.google.gerrit.server.git.validators.CommitValidationListener;
import com.google.gerrit.server.git.validators.CommitValidationMessage;
import com.google.gerrit.server.logging.LoggingContext;
import com.google.gerrit.server.logging.PerformanceLogger;
import com.google.gerrit.server.logging.TraceContext;
import com.google.gerrit.server.project.CreateProjectArgs;
import com.google.gerrit.server.validators.ProjectCreationValidationListener;
import com.google.gerrit.server.validators.ValidationException;
import com.google.inject.Inject;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.SortedMap;
import java.util.SortedSet;
import org.apache.http.message.BasicHeader;
import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;

public class TraceIT extends AbstractDaemonTest {
  @Rule public final Expect expect = Expect.create();

  @Inject private DynamicSet<ProjectCreationValidationListener> projectCreationValidationListeners;
  @Inject private DynamicSet<CommitValidationListener> commitValidationListeners;
  @Inject private DynamicSet<PerformanceLogger> performanceLoggers;
  @Inject private WorkQueue workQueue;

  private TraceValidatingProjectCreationValidationListener projectCreationListener;
  private RegistrationHandle projectCreationListenerRegistrationHandle;
  private TraceValidatingCommitValidationListener commitValidationListener;
  private RegistrationHandle commitValidationRegistrationHandle;
  private TestPerformanceLogger testPerformanceLogger;
  private RegistrationHandle performanceLoggerRegistrationHandle;

  @Before
  public void setup() {
    projectCreationListener = new TraceValidatingProjectCreationValidationListener();
    projectCreationListenerRegistrationHandle =
        projectCreationValidationListeners.add("gerrit", projectCreationListener);
    commitValidationListener = new TraceValidatingCommitValidationListener();
    commitValidationRegistrationHandle =
        commitValidationListeners.add("gerrit", commitValidationListener);
    testPerformanceLogger = new TestPerformanceLogger();
    performanceLoggerRegistrationHandle = performanceLoggers.add("gerrit", testPerformanceLogger);
  }

  @After
  public void cleanup() {
    projectCreationListenerRegistrationHandle.remove();
    commitValidationRegistrationHandle.remove();
    performanceLoggerRegistrationHandle.remove();
  }

  @Test
  public void restCallWithoutTrace() throws Exception {
    RestResponse response = adminRestSession.put("/projects/new1");
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isNull();
    assertThat(projectCreationListener.traceId).isNull();
    assertThat(projectCreationListener.isLoggingForced).isFalse();
  }

  @Test
  public void restCallWithTraceRequestParam() throws Exception {
    RestResponse response =
        adminRestSession.put("/projects/new2?" + ParameterParser.TRACE_PARAMETER);
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isNotNull();
    assertThat(projectCreationListener.traceId).isNotNull();
    assertThat(projectCreationListener.isLoggingForced).isTrue();
  }

  @Test
  public void restCallWithTraceRequestParamAndProvidedTraceId() throws Exception {
    RestResponse response =
        adminRestSession.put("/projects/new3?" + ParameterParser.TRACE_PARAMETER + "=issue/123");
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isEqualTo("issue/123");
    assertThat(projectCreationListener.traceId).isEqualTo("issue/123");
    assertThat(projectCreationListener.isLoggingForced).isTrue();
  }

  @Test
  public void restCallWithTraceHeader() throws Exception {
    RestResponse response =
        adminRestSession.putWithHeader(
            "/projects/new4", new BasicHeader(RestApiServlet.X_GERRIT_TRACE, null));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isNotNull();
    assertThat(projectCreationListener.traceId).isNotNull();
    assertThat(projectCreationListener.isLoggingForced).isTrue();
  }

  @Test
  public void restCallWithTraceHeaderAndProvidedTraceId() throws Exception {
    RestResponse response =
        adminRestSession.putWithHeader(
            "/projects/new5", new BasicHeader(RestApiServlet.X_GERRIT_TRACE, "issue/123"));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isEqualTo("issue/123");
    assertThat(projectCreationListener.traceId).isEqualTo("issue/123");
    assertThat(projectCreationListener.isLoggingForced).isTrue();
  }

  @Test
  public void restCallWithTraceRequestParamAndTraceHeader() throws Exception {
    // trace ID only specified by trace header
    RestResponse response =
        adminRestSession.putWithHeader(
            "/projects/new6?trace", new BasicHeader(RestApiServlet.X_GERRIT_TRACE, "issue/123"));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isEqualTo("issue/123");
    assertThat(projectCreationListener.traceId).isEqualTo("issue/123");
    assertThat(projectCreationListener.isLoggingForced).isTrue();

    // trace ID only specified by trace request parameter
    response =
        adminRestSession.putWithHeader(
            "/projects/new7?trace=issue/123", new BasicHeader(RestApiServlet.X_GERRIT_TRACE, null));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isEqualTo("issue/123");
    assertThat(projectCreationListener.traceId).isEqualTo("issue/123");
    assertThat(projectCreationListener.isLoggingForced).isTrue();

    // same trace ID specified by trace header and trace request parameter
    response =
        adminRestSession.putWithHeader(
            "/projects/new8?trace=issue/123",
            new BasicHeader(RestApiServlet.X_GERRIT_TRACE, "issue/123"));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeader(RestApiServlet.X_GERRIT_TRACE)).isEqualTo("issue/123");
    assertThat(projectCreationListener.traceId).isEqualTo("issue/123");
    assertThat(projectCreationListener.isLoggingForced).isTrue();

    // different trace IDs specified by trace header and trace request parameter
    response =
        adminRestSession.putWithHeader(
            "/projects/new9?trace=issue/123",
            new BasicHeader(RestApiServlet.X_GERRIT_TRACE, "issue/456"));
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);
    assertThat(response.getHeaders(RestApiServlet.X_GERRIT_TRACE))
        .containsExactly("issue/123", "issue/456");
    assertThat(projectCreationListener.traceIds).containsExactly("issue/123", "issue/456");
    assertThat(projectCreationListener.isLoggingForced).isTrue();
  }

  @Test
  public void pushWithoutTrace() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    PushOneCommit.Result r = push.to("refs/heads/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isNull();
    assertThat(commitValidationListener.isLoggingForced).isFalse();
  }

  @Test
  public void pushWithTrace() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    push.setPushOptions(ImmutableList.of("trace"));
    PushOneCommit.Result r = push.to("refs/heads/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isNotNull();
    assertThat(commitValidationListener.isLoggingForced).isTrue();
  }

  @Test
  public void pushWithTraceAndProvidedTraceId() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    push.setPushOptions(ImmutableList.of("trace=issue/123"));
    PushOneCommit.Result r = push.to("refs/heads/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isEqualTo("issue/123");
    assertThat(commitValidationListener.isLoggingForced).isTrue();
  }

  @Test
  public void pushForReviewWithoutTrace() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    PushOneCommit.Result r = push.to("refs/for/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isNull();
    assertThat(commitValidationListener.isLoggingForced).isFalse();
  }

  @Test
  public void pushForReviewWithTrace() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    push.setPushOptions(ImmutableList.of("trace"));
    PushOneCommit.Result r = push.to("refs/for/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isNotNull();
    assertThat(commitValidationListener.isLoggingForced).isTrue();
  }

  @Test
  public void pushForReviewWithTraceAndProvidedTraceId() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    push.setPushOptions(ImmutableList.of("trace=issue/123"));
    PushOneCommit.Result r = push.to("refs/for/master");
    r.assertOkStatus();
    assertThat(commitValidationListener.traceId).isEqualTo("issue/123");
    assertThat(commitValidationListener.isLoggingForced).isTrue();
  }

  @Test
  public void workQueueCopyLoggingContext() throws Exception {
    assertThat(LoggingContext.getInstance().getTags().isEmpty()).isTrue();
    assertForceLogging(false);
    try (TraceContext traceContext = TraceContext.open().forceLogging().addTag("foo", "bar")) {
      SortedMap<String, SortedSet<Object>> tagMap = LoggingContext.getInstance().getTags().asMap();
      assertThat(tagMap.keySet()).containsExactly("foo");
      assertThat(tagMap.get("foo")).containsExactly("bar");
      assertForceLogging(true);

      workQueue
          .createQueue(1, "test-queue")
          .submit(
              () -> {
                // Verify that the tags and force logging flag have been propagated to the new
                // thread.
                SortedMap<String, SortedSet<Object>> threadTagMap =
                    LoggingContext.getInstance().getTags().asMap();
                expect.that(threadTagMap.keySet()).containsExactly("foo");
                expect.that(threadTagMap.get("foo")).containsExactly("bar");
                expect
                    .that(LoggingContext.getInstance().shouldForceLogging(null, null, false))
                    .isTrue();
              })
          .get();

      // Verify that tags and force logging flag in the outer thread are still set.
      tagMap = LoggingContext.getInstance().getTags().asMap();
      assertThat(tagMap.keySet()).containsExactly("foo");
      assertThat(tagMap.get("foo")).containsExactly("bar");
      assertForceLogging(true);
    }
    assertThat(LoggingContext.getInstance().getTags().isEmpty()).isTrue();
    assertForceLogging(false);
  }

  @Test
  public void performanceLoggingForRestCall() throws Exception {
    RestResponse response = adminRestSession.put("/projects/new10");
    assertThat(response.getStatusCode()).isEqualTo(SC_CREATED);

    // This assertion assumes that the server invokes the PerformanceLogger plugins before it sends
    // the response to the client. If this assertion gets flaky it's likely that this got changed on
    // server-side.
    assertThat(testPerformanceLogger.logEntries()).isNotEmpty();
  }

  @Test
  public void performanceLoggingForPush() throws Exception {
    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
    PushOneCommit.Result r = push.to("refs/heads/master");
    r.assertOkStatus();
    assertThat(testPerformanceLogger.logEntries()).isNotEmpty();
  }

  private void assertForceLogging(boolean expected) {
    assertThat(LoggingContext.getInstance().shouldForceLogging(null, null, false))
        .isEqualTo(expected);
  }

  private static class TraceValidatingProjectCreationValidationListener
      implements ProjectCreationValidationListener {
    String traceId;
    ImmutableSet<String> traceIds;
    Boolean isLoggingForced;

    @Override
    public void validateNewProject(CreateProjectArgs args) throws ValidationException {
      this.traceId =
          Iterables.getFirst(LoggingContext.getInstance().getTagsAsMap().get("TRACE_ID"), null);
      this.traceIds = LoggingContext.getInstance().getTagsAsMap().get("TRACE_ID");
      this.isLoggingForced = LoggingContext.getInstance().shouldForceLogging(null, null, false);
    }
  }

  private static class TraceValidatingCommitValidationListener implements CommitValidationListener {
    String traceId;
    Boolean isLoggingForced;

    @Override
    public List<CommitValidationMessage> onCommitReceived(CommitReceivedEvent receiveEvent)
        throws CommitValidationException {
      this.traceId =
          Iterables.getFirst(LoggingContext.getInstance().getTagsAsMap().get("TRACE_ID"), null);
      this.isLoggingForced = LoggingContext.getInstance().shouldForceLogging(null, null, false);
      return ImmutableList.of();
    }
  }

  private static class TestPerformanceLogger implements PerformanceLogger {
    private List<PerformanceLogEntry> logEntries = new ArrayList<>();

    @Override
    public void log(String operation, long durationMs, Map<String, Optional<Object>> metaData) {
      logEntries.add(PerformanceLogEntry.create(operation, metaData));
    }

    ImmutableList<PerformanceLogEntry> logEntries() {
      return ImmutableList.copyOf(logEntries);
    }
  }

  @AutoValue
  abstract static class PerformanceLogEntry {
    static PerformanceLogEntry create(String operation, Map<String, Optional<Object>> metaData) {
      return new AutoValue_TraceIT_PerformanceLogEntry(operation, ImmutableMap.copyOf(metaData));
    }

    abstract String operation();

    abstract ImmutableMap<String, Object> metaData();
  }
}