// Copyright (C) 2014-2017 Bayerische Motoren Werke Aktiengesellschaft (BMW AG)
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

#include <chrono>
#include <condition_variable>
#include <iomanip>
#include <iostream>
#include <sstream>
#include <thread>
#include <map>
#include <algorithm>
#include <future>
#include <atomic>

#include <gtest/gtest.h>

#include <vsomeip/vsomeip.hpp>
#include <vsomeip/internal/logger.hpp>

#include "application_test_globals.hpp"

class application_test_client {
public:
    application_test_client(struct application_test::service_info _service_info) :
            service_info_(_service_info),
            app_(vsomeip::runtime::get()->create_application("client")),
            wait_until_registered_(true),
            wait_until_service_available_(true),
            wait_for_stop_(true),
            received_responses_(0),
            sent_requests_(0),
            stop_called_(false),
            stop_thread_(std::bind(&application_test_client::wait_for_stop, this)),
            send_thread_(std::bind(&application_test_client::send, this)) {
        if (!app_->init()) {
            ADD_FAILURE() << "Couldn't initialize application";
            return;
        }
        app_->register_state_handler(
                std::bind(&application_test_client::on_state, this,
                        std::placeholders::_1));

        app_->register_message_handler(vsomeip::ANY_SERVICE,
                vsomeip::ANY_INSTANCE, vsomeip::ANY_METHOD,
                std::bind(&application_test_client::on_message, this,
                        std::placeholders::_1));

        // register availability for all other services and request their event.
        app_->register_availability_handler(service_info_.service_id,
                service_info_.instance_id,
                std::bind(&application_test_client::on_availability, this,
                        std::placeholders::_1, std::placeholders::_2,
                        std::placeholders::_3));
        app_->request_service(service_info_.service_id,
                service_info_.instance_id);
        std::promise<bool> its_promise;
        application_thread_ = std::thread([&](){
            its_promise.set_value(true);
            app_->start();
        });
        EXPECT_TRUE(its_promise.get_future().get());
        std::this_thread::sleep_for(std::chrono::milliseconds(100));
    }

    ~application_test_client() {
        send_thread_.join();
        stop_thread_.join();
        application_thread_.join();
    }

    void on_state(vsomeip::state_type_e _state) {
        VSOMEIP_INFO << "Application " << app_->get_name() << " is "
        << (_state == vsomeip::state_type_e::ST_REGISTERED ?
                "registered." : "deregistered.");

        if (_state == vsomeip::state_type_e::ST_REGISTERED) {
            std::lock_guard<std::mutex> its_lock(mutex_);
            wait_until_registered_ = false;
            condition_.notify_one();
        }
    }

    void on_availability(vsomeip::service_t _service,
                         vsomeip::instance_t _instance, bool _is_available) {
            VSOMEIP_INFO << "Service [" << std::setw(4)
            << std::setfill('0') << std::hex << _service << "." << _instance
            << "] is " << (_is_available ? "available":"not available") << ".";
            std::lock_guard<std::mutex> its_lock(mutex_);
            if(_is_available) {
                wait_until_service_available_ = false;
                condition_.notify_one();
            } else {
                wait_until_service_available_ = true;
                condition_.notify_one();
            }
    }

    void on_message(const std::shared_ptr<vsomeip::message> &_message) {
        ++received_responses_;
        EXPECT_EQ(service_info_.service_id, _message->get_service());
        EXPECT_EQ(service_info_.method_id, _message->get_method());
        EXPECT_EQ(service_info_.instance_id, _message->get_instance());
        VSOMEIP_INFO << "Received a response with Client/Session [" << std::setw(4)
                << std::setfill('0') << std::hex << _message->get_client() << "/"
                << std::setw(4) << std::setfill('0') << std::hex
                << _message->get_session() << "]";
    }

    void send() {
        std::unique_lock<std::mutex> its_lock(mutex_);
        while (wait_until_registered_ && !stop_called_) {
            condition_.wait_for(its_lock, std::chrono::milliseconds(100));
        }

        while (wait_until_service_available_  && !stop_called_) {
            condition_.wait_for(its_lock, std::chrono::milliseconds(100));
        }
        its_lock.unlock();
        its_lock.release();

        for (;;) {
            bool send(false);
            {
                std::lock_guard<std::mutex> its_lock(mutex_);
                send = !wait_until_service_available_;
            }
            if (send && !stop_called_) {
                std::shared_ptr<vsomeip::message> its_req = vsomeip::runtime::get()->create_request();
                its_req->set_service(service_info_.service_id);
                its_req->set_instance(service_info_.instance_id);
                its_req->set_method(service_info_.method_id);
                app_->send(its_req);
                ++sent_requests_;
                VSOMEIP_INFO << "Sent a request to the service!";
                std::this_thread::sleep_for(std::chrono::milliseconds(100));
            } else {
                std::this_thread::sleep_for(std::chrono::milliseconds(50));
            }
            if(stop_called_) {
                break;
            }
        }
    }

    void wait_for_stop() {
        std::unique_lock<std::mutex> its_lock(stop_mutex_);
        while (wait_for_stop_) {
            stop_condition_.wait(its_lock);
        }
        VSOMEIP_INFO << "going down";
        app_->clear_all_handler();
        app_->stop();
    }

    void stop(bool check) {
        stop_called_ = true;
        std::lock_guard<std::mutex> its_lock(stop_mutex_);
        wait_for_stop_ = false;
        VSOMEIP_INFO << "going down. Sent " << sent_requests_
                << " requests and received " << received_responses_
                << " responses. Delta: " << sent_requests_ - received_responses_;
        std::uint32_t counter(0);
        if (check) {
            while(sent_requests_ == 0 || sent_requests_ < received_responses_) {
                std::this_thread::sleep_for(std::chrono::milliseconds(100));
                if(++counter > 50) {
                    break;
                }
            }
            EXPECT_GT(sent_requests_, 0u);
            EXPECT_GT(received_responses_, 0u);
            EXPECT_EQ(sent_requests_, received_responses_);
        }
        stop_condition_.notify_one();
    }

private:
    struct application_test::service_info service_info_;
    std::shared_ptr<vsomeip::application> app_;

    bool wait_until_registered_;
    bool wait_until_service_available_;
    std::mutex mutex_;
    std::condition_variable condition_;

    bool wait_for_stop_;
    std::mutex stop_mutex_;
    std::condition_variable stop_condition_;

    std::atomic<std::uint32_t> received_responses_;
    std::atomic<std::uint32_t> sent_requests_;
    std::atomic<bool> stop_called_;

    std::thread stop_thread_;
    std::thread send_thread_;
    std::thread application_thread_;
};