#include <gmock/gmock.h>

#include <map>

#include <process/clock.hpp>
#include <process/future.hpp>
#include <process/gtest.hpp>
#include <process/statistics.hpp>

#include <stout/duration.hpp>

using namespace process;

using std::map;


TEST(Statistics, set)
{
  Statistics statistics(Days(1));

  // Set one using Clock::now() implicitly.
  statistics.set("test", "statistic", 3.0);

  // Set one using Clock::now() explicitly.
  Seconds now(Clock::now());
  statistics.set("test", "statistic", 4.0, now);

  Future<map<Seconds, double> > values =
    statistics.timeseries("test", "statistic");

  AWAIT_ASSERT_READY(values);

  EXPECT_EQ(2, values.get().size());

  EXPECT_GE(Clock::now(), values.get().begin()->first.secs());
  EXPECT_DOUBLE_EQ(3.0, values.get().begin()->second);

  EXPECT_EQ(1, values.get().count(now));
  EXPECT_DOUBLE_EQ(4.0, values.get()[now]);
}


TEST(Statistics, truncate)
{
  Clock::pause();

  Statistics statistics(Days(1));

  statistics.set("test", "statistic", 3.0);

  Future<map<Seconds, double> > values =
    statistics.timeseries("test", "statistic");

  AWAIT_ASSERT_READY(values);

  EXPECT_EQ(1, values.get().size());
  EXPECT_GE(Clock::now(), values.get().begin()->first.secs());
  EXPECT_DOUBLE_EQ(3.0, values.get().begin()->second);

  Clock::advance(Days(1) + Seconds(1));
  Clock::settle();

  statistics.increment("test", "statistic");

  values = statistics.timeseries("test", "statistic");

  AWAIT_ASSERT_READY(values);

  EXPECT_EQ(1, values.get().size());
  EXPECT_GE(Clock::now(), values.get().begin()->first.secs());
  EXPECT_DOUBLE_EQ(4.0, values.get().begin()->second);

  Clock::resume();
}


TEST(Statistics, meter) {
  Statistics statistics(Days(1));

  // Set up a meter, and ensure it captures the expected time rate.
  Future<Try<Nothing> > meter =
    statistics.meter("test", "statistic", new meters::TimeRate("metered"));

  AWAIT_ASSERT_READY(meter);

  ASSERT_TRUE(meter.get().isSome());

  Seconds now(Clock::now());
  statistics.set("test", "statistic", 1.0, now);
  statistics.set("test", "statistic", 2.0, Seconds(now.secs() + 1.0));
  statistics.set("test", "statistic", 4.0, Seconds(now.secs() + 2.0));

  // Check the raw statistic values.
  Future<map<Seconds, double> > values =
    statistics.timeseries("test", "statistic");

  AWAIT_ASSERT_READY(values);

  EXPECT_EQ(3, values.get().size());
  EXPECT_EQ(1, values.get().count(now));
  EXPECT_EQ(1, values.get().count(Seconds(now.secs() + 1.0)));
  EXPECT_EQ(1, values.get().count(Seconds(now.secs() + 2.0)));

  EXPECT_EQ(1.0, values.get()[now]);
  EXPECT_EQ(2.0, values.get()[Seconds(now.secs() + 1.0)]);
  EXPECT_EQ(4.0, values.get()[Seconds(now.secs() + 2.0)]);

  // Now check the metered values.
  values = statistics.timeseries("test", "metered");

  AWAIT_ASSERT_READY(values);

  EXPECT_EQ(2, values.get().size());
  EXPECT_EQ(1, values.get().count(Seconds(now.secs() + 1.0)));
  EXPECT_EQ(1, values.get().count(Seconds(now.secs() + 2.0)));

  EXPECT_EQ(0., values.get()[now]);
  EXPECT_EQ(1.0, values.get()[Seconds(now.secs() + 1.0)]); // 100%.
  EXPECT_EQ(2.0, values.get()[Seconds(now.secs() + 2.0)]); // 200%.
}


TEST(Statistics, archive)
{
  Clock::pause();

  Statistics statistics(Seconds(10));

  // Create a meter and a statistic for archival.
  // Set up a meter, and ensure it captures the expected time rate.
  Future<Try<Nothing> > meter =
    statistics.meter("test", "statistic", new meters::TimeRate("metered"));

  AWAIT_ASSERT_READY(meter);

  ASSERT_TRUE(meter.get().isSome());

  Seconds now(Clock::now());
  statistics.set("test", "statistic", 1.0, now);
  statistics.set("test", "statistic", 2.0, Seconds(now.secs() + 1.0));

  // Archive and ensure the following:
  //   1. The statistic will no longer be part of the snapshot.
  //   2. Any meters associated with this statistic will be removed.
  //   3. However, the time series will be retained until the window expiration.
  statistics.archive("test", "statistic");

  // TODO(bmahler): Wait for JSON parsing to verify number 1.

  // Ensure the raw time series is present.
  Future<map<Seconds, double> > values =
    statistics.timeseries("test", "statistic");
  AWAIT_ASSERT_READY(values);
  EXPECT_FALSE(values.get().empty());

  // Ensure the metered timeseries is present.
  values = statistics.timeseries("test", "metered");
  AWAIT_ASSERT_READY(values);
  EXPECT_FALSE(values.get().empty());

  // Expire the window and ensure the statistics were removed.
  Clock::advance(STATISTICS_TRUNCATION_INTERVAL);
  Clock::settle();

  // Ensure the raw statistics are gone.
  values = statistics.timeseries("test", "statistic");
  AWAIT_ASSERT_READY(values);
  EXPECT_TRUE(values.get().empty());

  // Ensure the metered statistics are gone.
  values = statistics.timeseries("test", "metered");
  AWAIT_ASSERT_READY(values);
  EXPECT_TRUE(values.get().empty());

  // Reactivate the statistic, and make sure the meter is still missing.
  statistics.set("test", "statistic", 1.0, now);

  values = statistics.timeseries("test", "metered");
  AWAIT_ASSERT_READY(values);
  EXPECT_TRUE(values.get().empty());

  Clock::resume();
}