Add mpris module

Uses libplayerctl to use the MPRIS dbus protocol to query, listen and
control media players.

Signed-off-by: Robert Günzler <r@gnzler.io>

include/modules/mpris/mpris.hpp

@@ -0,0 +1,67 @@
+#pragma once
+
+#include <iostream>
+#include <string>
+
+#include "gtkmm/box.h"
+#include "gtkmm/label.h"
+
+extern "C" {
+#include <playerctl/playerctl.h>
+}
+
+#include "ALabel.hpp"
+#include "util/sleeper_thread.hpp"
+
+namespace waybar::modules::mpris {
+
+class Mpris : public AModule {
+ public:
+  Mpris(const std::string&, const Json::Value&);
+  ~Mpris();
+  auto update() -> void;
+  bool handleToggle(GdkEventButton* const&);
+
+ private:
+  static auto onPlayerNameAppeared(PlayerctlPlayerManager*, PlayerctlPlayerName*, gpointer) -> void;
+  static auto onPlayerNameVanished(PlayerctlPlayerManager*, PlayerctlPlayerName*, gpointer) -> void;
+  static auto onPlayerPlay(PlayerctlPlayer*, gpointer) -> void;
+  static auto onPlayerPause(PlayerctlPlayer*, gpointer) -> void;
+  static auto onPlayerStop(PlayerctlPlayer*, gpointer) -> void;
+  static auto onPlayerMetadata(PlayerctlPlayer*, GVariant*, gpointer) -> void;
+
+  struct PlayerInfo {
+    std::string name;
+    PlayerctlPlaybackStatus status;
+    std::string status_string;
+
+    std::optional<std::string> artist;
+    std::optional<std::string> album;
+    std::optional<std::string> title;
+    std::optional<std::string> length;  // as HH:MM:SS
+  };
+
+  auto getPlayerInfo() -> std::optional<PlayerInfo>;
+  auto getIcon(const Json::Value&, const std::string&) -> std::string;
+
+  Gtk::Box box_;
+  Gtk::Label label_;
+
+  // config
+  std::string format_;
+  std::string format_playing_;
+  std::string format_paused_;
+  std::string format_stopped_;
+  std::chrono::seconds interval_;
+  std::string player_;
+  std::vector<std::string> ignored_players_;
+
+  PlayerctlPlayerManager* manager;
+  PlayerctlPlayer* player;
+  std::string lastStatus;
+  std::string lastPlayer;
+
+  util::SleeperThread thread_;
+};
+
+}  // namespace waybar::modules::mpris