1 files changed, 59 insertions, 0 deletions
diff --git a/src/openvic-simulation/misc/SimulationClock.hpp b/src/openvic-simulation/misc/SimulationClock.hpp
new file mode 100644
index 0000000..fbf7930
--- /dev/null
+++ b/src/openvic-simulation/misc/SimulationClock.hpp
@@ -0,0 +1,59 @@
+#pragma once
+
+#include <chrono>
+#include <functional>
+#include <vector>
+
+#include "openvic-simulation/utility/Getters.hpp"
+
+namespace OpenVic {
+	/* Conditionally advances game depending on speed and pause state. */
+	class SimulationClock {
+	public:
+		using tick_function_t = std::function<void()>;
+		using update_function_t = std::function<void()>;
+		using state_changed_function_t = std::function<void()>;
+		using speed_t = int8_t;
+
+		/* Minimum number of miliseconds before the simulation advances
+		 * (in descending duration order, hence increasing speed order). */
+		static constexpr std::chrono::milliseconds GAME_SPEEDS[] {
+			std::chrono::milliseconds { 3000 }, std::chrono::milliseconds { 2000 }, std::chrono::milliseconds { 1000 },
+			std::chrono::milliseconds { 100 }, std::chrono::milliseconds { 1 }
+		};
+		static constexpr speed_t MIN_SPEED = 0, MAX_SPEED = std::size(GAME_SPEEDS) - 1;
+
+	private:
+		using time_point_t = std::chrono::time_point<std::chrono::high_resolution_clock>;
+
+		/* Advance simulation (triggered while unpaused at interval determined by speed). */
+		tick_function_t tick_function;
+		/* Refresh game state (triggered with every call to conditionally_advance_game). */
+		update_function_t update_function;
+		/* Callback for when speed or pause state is changed. */
+		state_changed_function_t state_changed_function;
+
+		time_point_t last_tick_time;
+		speed_t PROPERTY_CUSTOM_NAME(current_speed, get_simulation_speed);
+		bool PROPERTY_CUSTOM_PREFIX(paused, is);
+
+	public:
+
+		SimulationClock(
+			tick_function_t new_tick_function, update_function_t new_update_function,
+			state_changed_function_t new_state_changed_function
+		);
+
+		void set_paused(bool new_paused);
+		void toggle_paused();
+
+		void set_simulation_speed(speed_t speed);
+		void increase_simulation_speed();
+		void decrease_simulation_speed();
+		bool can_increase_simulation_speed() const;
+		bool can_decrease_simulation_speed() const;
+
+		void conditionally_advance_game();
+		void reset();
+	};
+}