#include "util/MockAssert.hpp"
#include "util/prometheus/Counter.hpp"
#include "util/prometheus/OStream.hpp"

#include <gmock/gmock.h>
#include <gtest/gtest.h>

#include <cstdint>
#include <string>
#include <thread>
#include <utility>

using namespace util::prometheus;

struct AnyCounterTests : virtual ::testing::Test {
    struct MockCounterImpl {
        using ValueType = std::uint64_t;
        MOCK_METHOD(void, add, (ValueType));
        MOCK_METHOD(void, set, (ValueType));
        MOCK_METHOD(ValueType, value, (), (const));
    };

    ::testing::StrictMock<MockCounterImpl> mockCounterImpl;
    std::string const name = "test_counter";
    std::string labelsString = R"JSON({label1="value1",label2="value2"})JSON";
    CounterInt counter{name, labelsString, static_cast<MockCounterImpl&>(mockCounterImpl)};
};

TEST_F(AnyCounterTests, name)
{
    EXPECT_EQ(counter.name(), name);
}

TEST_F(AnyCounterTests, labelsString)
{
    EXPECT_EQ(counter.labelsString(), labelsString);
}

TEST_F(AnyCounterTests, serialize)
{
    EXPECT_CALL(mockCounterImpl, value()).WillOnce(::testing::Return(42));
    OStream stream{false};
    counter.serializeValue(stream);
    EXPECT_EQ(std::move(stream).data(), R"(test_counter{label1="value1",label2="value2"} 42)");
}

TEST_F(AnyCounterTests, operatorAdd)
{
    EXPECT_CALL(mockCounterImpl, add(1));
    ++counter;
    EXPECT_CALL(mockCounterImpl, add(42));
    counter += 42;
}

TEST_F(AnyCounterTests, set)
{
    EXPECT_CALL(mockCounterImpl, value()).WillOnce(::testing::Return(4));
    EXPECT_CALL(mockCounterImpl, set(42));
    counter.set(42);
}

TEST_F(AnyCounterTests, reset)
{
    EXPECT_CALL(mockCounterImpl, set(0));
    counter.reset();
}

TEST_F(AnyCounterTests, value)
{
    EXPECT_CALL(mockCounterImpl, value()).WillOnce(::testing::Return(42));
    EXPECT_EQ(counter.value(), 42);
}

struct AnyCounterAssertTest : common::util::WithMockAssert, AnyCounterTests {};

TEST_F(AnyCounterAssertTest, setLowerValue)
{
    testing::Mock::AllowLeak(&mockCounterImpl);
    EXPECT_CLIO_ASSERT_FAIL({
        EXPECT_CALL(mockCounterImpl, value()).WillOnce(::testing::Return(50));
        counter.set(42);
    });
}

struct CounterIntTests : ::testing::Test {
    CounterInt counter{"test_counter", R"(label1="value1",label2="value2")"};
};

TEST_F(CounterIntTests, operatorAdd)
{
    ++counter;
    counter += 24;
    EXPECT_EQ(counter.value(), 25);
}

TEST_F(CounterIntTests, reset)
{
    ++counter;
    EXPECT_EQ(counter.value(), 1);
    counter.reset();
    EXPECT_EQ(counter.value(), 0);
}

TEST_F(CounterIntTests, multithreadAdd)
{
    static constexpr auto kNUM_ADDITIONS = 1000;
    static constexpr auto kNUM_NUMBER_ADDITIONS = 100;
    static constexpr auto kNUMBER_TO_ADD = 11;
    std::thread thread1([&] {
        for (int i = 0; i < kNUM_ADDITIONS; ++i) {
            ++counter;
        }
    });
    std::thread thread2([&] {
        for (int i = 0; i < kNUM_NUMBER_ADDITIONS; ++i) {
            counter += kNUMBER_TO_ADD;
        }
    });
    thread1.join();
    thread2.join();
    EXPECT_EQ(counter.value(), kNUM_ADDITIONS + (kNUM_NUMBER_ADDITIONS * kNUMBER_TO_ADD));
}

struct CounterDoubleTests : ::testing::Test {
    CounterDouble counter{"test_counter", R"(label1="value1",label2="value2")"};
};

TEST_F(CounterDoubleTests, operatorAdd)
{
    ++counter;
    counter += 24.1234;
    EXPECT_NEAR(counter.value(), 25.1234, 1e-9);
}

TEST_F(CounterDoubleTests, reset)
{
    ++counter;
    EXPECT_EQ(counter.value(), 1.);
    counter.reset();
    EXPECT_EQ(counter.value(), 0.);
}

TEST_F(CounterDoubleTests, multithreadAdd)
{
    static constexpr auto kNUM_ADDITIONS = 1000;
    static constexpr auto kNUM_NUMBER_ADDITIONS = 100;
    static constexpr auto kNUMBER_TO_ADD = 11.1234;
    std::thread thread1([&] {
        for (int i = 0; i < kNUM_ADDITIONS; ++i) {
            ++counter;
        }
    });
    std::thread thread2([&] {
        for (int i = 0; i < kNUM_NUMBER_ADDITIONS; ++i) {
            counter += kNUMBER_TO_ADD;
        }
    });
    thread1.join();
    thread2.join();
    EXPECT_NEAR(counter.value(), kNUM_ADDITIONS + (kNUM_NUMBER_ADDITIONS * kNUMBER_TO_ADD), 1e-9);
}