/**
 * (C) 2016 - 2021 KISTLER INSTRUMENTE AG, Winterthur, Switzerland
 * (C) 2016 - 2022 Stanislav Angelovic <stanislav.angelovic@protonmail.com>
 *
 * @file TestFixture.h
 *
 * Created on: Jan 2, 2017
 * Project: sdbus-c++
 * Description: High-level D-Bus IPC C++ library based on sd-bus
 *
 * This file is part of sdbus-c++.
 *
 * sdbus-c++ is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * sdbus-c++ is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with sdbus-c++. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef SDBUS_CPP_INTEGRATIONTESTS_TESTFIXTURE_H_
#define SDBUS_CPP_INTEGRATIONTESTS_TESTFIXTURE_H_

#include "TestAdaptor.h"
#include "TestProxy.h"
#include "Defs.h"

#include <gtest/gtest.h>
#include <gmock/gmock.h>
#include <systemd/sd-event.h>
#include <sys/eventfd.h>

#include <thread>
#include <chrono>
#include <atomic>
#include <chrono>

namespace sdbus { namespace test {

class BaseTestFixture : public ::testing::Test
{
public:
    static void SetUpTestCase()
    {
        s_adaptorConnection->requestName(BUS_NAME);
    }

    static void TearDownTestCase()
    {
        s_adaptorConnection->releaseName(BUS_NAME);
    }

    template <typename _Fnc>
    static bool waitUntil(_Fnc&& fnc, std::chrono::milliseconds timeout = std::chrono::seconds(5))
    {
        using namespace std::chrono_literals;

        std::chrono::milliseconds elapsed{};
        std::chrono::milliseconds step{5ms};
        do {
            std::this_thread::sleep_for(step);
            elapsed += step;
            if (elapsed > timeout)
                return false;
        } while (!fnc());

        return true;
    }

    static bool waitUntil(std::atomic<bool>& flag, std::chrono::milliseconds timeout = std::chrono::seconds(5))
    {
        return waitUntil([&flag]() -> bool { return flag; }, timeout);
    }

private:
    void SetUp() override
    {
      m_objectManagerProxy = std::make_unique<ObjectManagerTestProxy>(*s_proxyConnection, BUS_NAME, MANAGER_PATH);
      m_proxy = std::make_unique<TestProxy>(*s_proxyConnection, BUS_NAME, OBJECT_PATH);

      m_objectManagerAdaptor = std::make_unique<ObjectManagerTestAdaptor>(*s_adaptorConnection, MANAGER_PATH);
      m_adaptor = std::make_unique<TestAdaptor>(*s_adaptorConnection, OBJECT_PATH);
    }

    void TearDown() override
    {
      m_proxy.reset();
      m_adaptor.reset();
    }

public:
    static std::unique_ptr<sdbus::IConnection> s_adaptorConnection;
    static std::unique_ptr<sdbus::IConnection> s_proxyConnection;
    std::unique_ptr<ObjectManagerTestAdaptor> m_objectManagerAdaptor;
    std::unique_ptr<ObjectManagerTestProxy> m_objectManagerProxy;
    std::unique_ptr<TestAdaptor> m_adaptor;
    std::unique_ptr<TestProxy> m_proxy;
};

struct SdBusCppLoop{};
struct SdEventLoop{};

template <typename _EventLoop>
class TestFixture : public BaseTestFixture{};

// Fixture working upon internal sdbus-c++ event loop
template <>
class TestFixture<SdBusCppLoop> : public BaseTestFixture
{
public:
    static void SetUpTestCase()
    {
        BaseTestFixture::SetUpTestCase();
        s_proxyConnection->enterEventLoopAsync();
        s_adaptorConnection->enterEventLoopAsync();
        std::this_thread::sleep_for(std::chrono::milliseconds(50)); // Give time for the proxy connection to start listening to signals
    }

    static void TearDownTestCase()
    {
        BaseTestFixture::TearDownTestCase();
        s_adaptorConnection->leaveEventLoop();
        s_proxyConnection->leaveEventLoop();
    }
};

// Fixture working upon attached external sd-event loop
template <>
class TestFixture<SdEventLoop> : public BaseTestFixture
{
public:
    static void SetUpTestCase()
    {
        sd_event_new(&s_adaptorSdEvent);
        sd_event_new(&s_proxySdEvent);

        s_adaptorConnection->attachSdEventLoop(s_adaptorSdEvent);
        s_proxyConnection->attachSdEventLoop(s_proxySdEvent);

        s_eventExitFd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
        // No callback means that the event loop will exit when this event source triggers
        sd_event_add_io(s_adaptorSdEvent, nullptr, s_eventExitFd, EPOLLIN, nullptr, NULL);
        sd_event_add_io(s_proxySdEvent, nullptr, s_eventExitFd, EPOLLIN, nullptr, NULL);

        s_adaptorEventLoopThread = std::thread([]()
        {
            sd_event_loop(s_adaptorSdEvent);
        });
        s_proxyEventLoopThread = std::thread([]()
        {
            sd_event_loop(s_proxySdEvent);
        });

        BaseTestFixture::SetUpTestCase();
        std::this_thread::sleep_for(std::chrono::milliseconds(50)); // Give time for the proxy connection to start listening to signals
    }

    static void TearDownTestCase()
    {
        uint64_t value = 1;
        write(s_eventExitFd, &value, sizeof(value));

        s_adaptorEventLoopThread.join();
        s_proxyEventLoopThread.join();

        sd_event_unref(s_adaptorSdEvent);
        sd_event_unref(s_proxySdEvent);
        close(s_eventExitFd);

        BaseTestFixture::TearDownTestCase();
    }

private:
    static std::thread s_adaptorEventLoopThread;
    static std::thread s_proxyEventLoopThread;
    static sd_event *s_adaptorSdEvent;
    static sd_event *s_proxySdEvent;
    static int s_eventExitFd;
};

typedef ::testing::Types<SdBusCppLoop, SdEventLoop> EventLoopTags;

TYPED_TEST_SUITE(TestFixture, EventLoopTags);

template <typename _EventLoop>
using SdbusTestObject = TestFixture<_EventLoop>;
TYPED_TEST_SUITE(SdbusTestObject, EventLoopTags);

template <typename _EventLoop>
using AsyncSdbusTestObject = TestFixture<_EventLoop>;
TYPED_TEST_SUITE(AsyncSdbusTestObject, EventLoopTags);

template <typename _EventLoop>
using AConnection = TestFixture<_EventLoop>;
TYPED_TEST_SUITE(AConnection, EventLoopTags);

}}

#endif /* SDBUS_CPP_INTEGRATIONTESTS_TESTFIXTURE_H_ */