// gKeyMapper - talk to gkeymapper-daemon over the session bus.
#ifndef GKEYMAPPER_DAEMONCLIENT_H
#define GKEYMAPPER_DAEMONCLIENT_H

#include <gio/gio.h>

#include <functional>
#include <string>

namespace gkeymapper {

// What the footer needs to know about the daemon.
struct DaemonStatus {
    bool reachable = false;
    std::string version;
    std::string device;
    std::string configPath;
};

// Control-plane client for the daemon. Every call is asynchronous and its
// result arrives on the GTK main loop, so the UI never blocks on the daemon
// (a call is answered at most one daemon loop iteration late). Keypresses never
// travel through here.
class DaemonClient {
public:
    using StatusFn = std::function<void(const DaemonStatus&)>;
    using KeyFn = std::function<void(int index, const std::string& action)>;

    DaemonClient() = default;
    ~DaemonClient();

    DaemonClient(const DaemonClient&) = delete;
    DaemonClient& operator=(const DaemonClient&) = delete;

    void init(StatusFn onStatus, KeyFn onKey);

    // Best effort: asks the daemon to re-read the mappings file. Its file watch
    // would pick the save up by itself, this only makes it immediate.
    void reload();

private:
    static void on_bus_ready(GObject* source, GAsyncResult* result, gpointer userData);
    static void on_daemon_signal(GDBusConnection* connection, const gchar* sender,
                                 const gchar* objectPath, const gchar* interfaceName,
                                 const gchar* signalName, GVariant* parameters,
                                 gpointer userData);
    static void on_name_owner_changed(GDBusConnection* connection, const gchar* sender,
                                      const gchar* objectPath, const gchar* interfaceName,
                                      const gchar* signalName, GVariant* parameters,
                                      gpointer userData);
    static void on_status_reply(GObject* source, GAsyncResult* result, gpointer userData);
    static void on_reload_reply(GObject* source, GAsyncResult* result, gpointer userData);

    void watch_signals();
    void fetch_status();
    void report_unreachable();
    void publish(const DaemonStatus& status);

    GDBusConnection* connection_ = nullptr;
    guint signal_subscription_ = 0;
    guint name_subscription_ = 0;
    bool started_ = false;
    StatusFn onStatus_;
    KeyFn onKey_;
};

} // namespace gkeymapper

#endif // GKEYMAPPER_DAEMONCLIENT_H