#include "client_manager.hh"

#include "buffer_manager.hh"
#include "color_registry.hh"
#include "command_manager.hh"
#include "event_manager.hh"
#include "file.hh"
#include "user_interface.hh"
#include "window.hh"

namespace Kakoune
{

ClientManager::ClientManager() = default;
ClientManager::~ClientManager() = default;

String ClientManager::generate_name() const
{
    for (int i = 0; true; ++i)
    {
        String name = "unnamed" + to_string(i);
        if (validate_client_name(name))
            return name;
    }
}

Client* ClientManager::create_client(std::unique_ptr<UserInterface>&& ui,
                                     const String& init_commands)
{
    Buffer& buffer = **BufferManager::instance().begin();
    Client* client = new Client{std::move(ui), get_unused_window_for_buffer(buffer),
                                            generate_name()};
    m_clients.emplace_back(client);
    try
    {
        CommandManager::instance().execute(init_commands, client->context());
    }
    catch (Kakoune::runtime_error& error)
    {
        client->context().print_status({ error.what(), get_color("Error") });
        client->context().hooks().run_hook("RuntimeError", error.what(),
                                           client->context());
    }
    catch (Kakoune::client_removed&)
    {
        m_clients.pop_back();
        return nullptr;
    }

    client->ui().set_input_callback([client, this]() {
        try
        {
            client->handle_available_input();
        }
        catch (Kakoune::runtime_error& error)
        {
            client->context().print_status({ error.what(), get_color("Error") });
            client->context().hooks().run_hook("RuntimeError", error.what(),
                                               client->context());
        }
        catch (Kakoune::client_removed&)
        {
            ClientManager::instance().remove_client(*client);
        }
    });

    return client;
}

void ClientManager::remove_client(Client& client)
{
    for (auto it = m_clients.begin(); it != m_clients.end(); ++it)
    {
        if (it->get() == &client)
        {
             m_clients.erase(it);
             return;
        }
    }
    kak_assert(false);
}

Window& ClientManager::get_unused_window_for_buffer(Buffer& buffer)
{
    for (auto& w : m_windows)
    {
        if (&w->buffer() != &buffer)
           continue;

        auto it = std::find_if(m_clients.begin(), m_clients.end(),
                               [&](const std::unique_ptr<Client>& client)
                               { return &client->context().window() == w.get(); });
        if (it == m_clients.end())
        {
            w->forget_timestamp();
            return *w;
        }
    }
    m_windows.emplace_back(new Window(buffer));
    return *m_windows.back();
}

void ClientManager::ensure_no_client_uses_buffer(Buffer& buffer)
{
    for (auto& client : m_clients)
    {
        client->context().forget_jumps_to_buffer(buffer);

        if (&client->context().buffer() != &buffer)
            continue;

        if (client->context().editor().is_editing())
            throw runtime_error("client '" + client->context().name() + "' is inserting in '" +
                                buffer.display_name() + '\'');

        // change client context to edit the first buffer which is not the
        // specified one. As BufferManager stores buffer according to last
        // access, this selects a sensible buffer to display.
        for (auto& buf : BufferManager::instance())
        {
            if (buf != &buffer)
            {
               Window& w = get_unused_window_for_buffer(*buf);
               client->context().change_editor(w);
               break;
            }
        }
    }
    auto end = std::remove_if(m_windows.begin(), m_windows.end(),
                              [&buffer](const std::unique_ptr<Window>& w)
                              { return &w->buffer() == &buffer; });
    m_windows.erase(end, m_windows.end());
}

bool ClientManager::validate_client_name(const String& name) const
{
    auto it = find_if(m_clients, [&](const std::unique_ptr<Client>& client)
                                 { return client->context().name() == name; });
    return it == m_clients.end();
}

Client& ClientManager::get_client(const String& name)
{
    for (auto& client : m_clients)
    {
        if (client->context().name() == name)
            return *client;
    }
    throw runtime_error("no client named: " + name);
}

void ClientManager::redraw_clients() const
{
    for (auto& client : m_clients)
        client->redraw_ifn();
}

}