#include <Wt/WBootstrap3Theme.h>
#include <Wt/WDialog.h>
#include <Wt/WEnvironment.h>
#include <Wt/WPushButton.h>
#include <Wt/WServer.h>
#include <Wt/WVBoxLayout.h>

Wt::WContainerWidget *m_displayedLayout = nullptr;

void setContainerActive(Wt::WVBoxLayout *layout, std::unique_ptr<Wt::WContainerWidget> container)
{
    if (m_displayedLayout != nullptr)
    {
        m_displayedLayout->removeFromParent();
        m_displayedLayout = nullptr;
    }

    m_displayedLayout = layout->addWidget(std::move(container), 1);
}

std::unique_ptr<Wt::WContainerWidget> buildContainer()
{
    auto container  = std::make_unique<Wt::WContainerWidget>();
    auto gridLayout = container->setLayout(std::make_unique<Wt::WGridLayout>());

    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Text1"), 0, 0, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Text2"), 1, 0, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Text3"), 2, 0, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Text4"), 3, 0, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);

    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Value1"), 0, 1, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Value2"), 1, 1, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Value3"), 2, 1, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);
    gridLayout->addWidget(
        std::make_unique<Wt::WText>("Value4"), 3, 1, Wt::AlignmentFlag::Justify | Wt::AlignmentFlag::Top);

    return container;
}

std::unique_ptr<Wt::WApplication> createApplication(const Wt::WEnvironment &env)
{
    auto app = std::make_unique<Wt::WApplication>(env);

    auto appTheme = std::make_shared<Wt::WBootstrap3Theme>();

    app->setTheme(appTheme);

    auto layout = app->root()->setLayout(std::make_unique<Wt::WVBoxLayout>());
    auto button = layout->addWidget(std::make_unique<Wt::WPushButton>("Update Container"));

    auto container = buildContainer();
    setContainerActive(layout, std::move(container));

    button->clicked().connect([layout]() {
        auto container = buildContainer();
        setContainerActive(layout, std::move(container));
    });

    return app;
}

int main(int argc, char **argv)
{
    try
    {
        Wt::WServer server(argc, argv, WTHTTP_CONFIGURATION);

        server.addEntryPoint(Wt::EntryPointType::Application, std::bind(createApplication, std::placeholders::_1));

        server.run();
    }
    catch (Wt::WException &e)
    {
        std::cerr << "Exception: " << e.what() << std::endl;
    }
}