#include <frame_statistics.hpp>
#include <gtest/gtest.h>
#include <limits>

namespace aethera::web {
TEST(Sliding_Statistics, Publishes_Derived_Window_Statistics_On_Submit) {
    Sliding_Statistics statistics{20};
    for (int value = 1; value <= 20; ++value)
        static_cast<void>(statistics.submit(static_cast<double>(value)));

    const auto& state = statistics.state();
        EXPECT_EQ(state.count, 20U);
        EXPECT_DOUBLE_EQ(state.latest, 20.0);
        EXPECT_DOUBLE_EQ(state.minimum, 1.0);
        EXPECT_DOUBLE_EQ(state.maximum, 20.0);
        EXPECT_DOUBLE_EQ(state.average, 10.5);
        EXPECT_DOUBLE_EQ(state.trimmed_average, 10.5);
        EXPECT_NEAR(state.p50, 10.0, 2.0);
        EXPECT_GE(state.p95, 15.0);
        EXPECT_LE(state.p95, 20.0);
        EXPECT_GE(state.p99, state.p95);
        EXPECT_LE(state.p99, 20.0);
}

TEST(Sliding_Statistics, Overwrites_Oldest_And_Ignores_Nonfinite_Values) {
    Sliding_Statistics statistics{3};
    static_cast<void>(statistics.submit(1.0));
    static_cast<void>(statistics.submit(2.0));
    static_cast<void>(statistics.submit(std::numeric_limits<double>::infinity()));
    static_cast<void>(statistics.submit(3.0));
    static_cast<void>(statistics.submit(4.0));

    const auto& state = statistics.state();
        EXPECT_EQ(state.count, 3U);
        EXPECT_DOUBLE_EQ(state.latest, 4.0);
        EXPECT_DOUBLE_EQ(state.minimum, 2.0);
        EXPECT_DOUBLE_EQ(state.maximum, 4.0);
        EXPECT_DOUBLE_EQ(state.average, 3.0);
}

TEST(Sliding_Statistics, Estimates_Quantiles_Without_Growing_The_Window) {
    Sliding_Statistics statistics{64};
    for (int value = 1; value <= 1000; ++value)
        static_cast<void>(statistics.submit(static_cast<double>(value)));

    const auto& state = statistics.state();
    EXPECT_EQ(state.count, 64U);
    EXPECT_NEAR(state.average, 968.5, 0.001);
    EXPECT_DOUBLE_EQ(state.minimum, 937.0);
    EXPECT_DOUBLE_EQ(state.maximum, 1000.0);
    EXPECT_NEAR(state.p50, 500.0, 10.0);
    EXPECT_NEAR(state.p95, 950.0, 15.0);
    EXPECT_NEAR(state.p99, 990.0, 15.0);
}
}