package com.googlesource.gerrit.plugins.healthcheck;

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

import com.google.gerrit.metrics.Counter0;
import com.google.gerrit.metrics.Description;
import com.google.gerrit.metrics.DisabledMetricMaker;
import com.google.gerrit.metrics.Timer0;
import com.googlesource.gerrit.plugins.healthcheck.check.HealthCheck.Result;
import com.googlesource.gerrit.plugins.healthcheck.check.HealthCheck.Status;
import com.googlesource.gerrit.plugins.healthcheck.check.MetricsHandler;
import java.util.concurrent.TimeUnit;
import org.junit.Test;

public class MetricsHandlerTest {

  private class TestMetricsMaker extends DisabledMetricMaker {
    private Long failures = 0L;
    private Long latency = 0L;

    @Override
    public Counter0 newCounter(String name, Description desc) {
      return new Counter0() {
        @Override
        public void incrementBy(long value) {
          failures += value;
        }

        @Override
        public void remove() {}
      };
    }

    @Override
    public Timer0 newTimer(String name, Description desc) {
      return new Timer0() {
        @Override
        public void remove() {}

        @Override
        public void record(long value, TimeUnit unit) {
          latency = value;
        }
      };
    }
  }

  @Test
  public void shouldSendCounterWhenStatusFailed() {
    TestMetricsMaker metricMaker = new TestMetricsMaker();
    MetricsHandler handler = new MetricsHandler("test", metricMaker);

    handler.sendMetrics(new Status(Result.FAILED, 1L, 1L));

    assertThat(metricMaker.failures).isEqualTo(1L);
  }

  @Test
  public void shouldSendCounterWhenStatusTimeout() {
    TestMetricsMaker metricMaker = new TestMetricsMaker();
    MetricsHandler handler = new MetricsHandler("test", metricMaker);

    handler.sendMetrics(new Status(Result.TIMEOUT, 1L, 1L));

    assertThat(metricMaker.failures).isEqualTo(1L);
  }

  @Test
  public void shouldNOTSendCounterWhenStatusSuccess() {
    TestMetricsMaker metricMaker = new TestMetricsMaker();
    MetricsHandler handler = new MetricsHandler("test", metricMaker);

    handler.sendMetrics(new Status(Result.PASSED, 1L, 1L));

    assertThat(metricMaker.failures).isEqualTo(0L);
  }

  @Test
  public void shouldRecordLatencyWhenSuccess() {
    TestMetricsMaker metricMaker = new TestMetricsMaker();
    MetricsHandler handler = new MetricsHandler("test", metricMaker);
    Long elapsed = System.currentTimeMillis();

    handler.sendMetrics(new Status(Result.PASSED, 1L, elapsed));

    assertThat(metricMaker.latency).isEqualTo(elapsed);
  }

  @Test
  public void shouldRecordLatencyWhenFailure() {
    TestMetricsMaker metricMaker = new TestMetricsMaker();
    MetricsHandler handler = new MetricsHandler("test", metricMaker);
    Long elapsed = System.currentTimeMillis();

    handler.sendMetrics(new Status(Result.FAILED, 1L, elapsed));

    assertThat(metricMaker.latency).isEqualTo(elapsed);
  }
}