1 files changed, 88 insertions, 0 deletions
diff --git a/src/input.hpp b/src/input.hpp
new file mode 100644
index 0000000..39d4045
--- /dev/null
+++ b/src/input.hpp
@@ -0,0 +1,88 @@
+/**
+ * @file window.hpp
+ * Handles user input received from SDL.
+ *
+ * Copyright (C) 2019 Clyne Sullivan
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef INPUT_HPP_
+#define INPUT_HPP_
+
+#include <entityx/entityx.h>
+#include <SDL2/SDL.h>
+
+/**
+ * @class KeyUpEvent
+ * Stores info regarding key releases.
+ */
+struct KeyUpEvent {
+	KeyUpEvent(const SDL_Keysym& keysym) :
+		sym(keysym.sym), mod(keysym.mod) {}
+
+	SDL_Keycode sym;
+	Uint16 mod;
+};
+
+/**
+ * @class KeyDownEvent
+ * Stores info regarding key presses.
+ */
+struct KeyDownEvent {
+	KeyDownEvent(const SDL_Keysym& keysym) :
+		sym(keysym.sym), mod(keysym.mod) {}
+
+	SDL_Keycode sym;
+	Uint16 mod;
+};
+
+/**
+ * @class InputSystem
+ * Listens for user input from SDL, and emits input events accordingly.
+ */
+class InputSystem : public entityx::System<InputSystem> {
+public:
+	/**
+	 * Prepares the system for running.
+	 */
+	void configure([[maybe_unused]] entityx::EntityManager& entities,
+		[[maybe_unused]] entityx::EventManager& events) final {
+	}
+
+	/**
+	 * Updates the system by checking for SDL events.
+	 */
+	void update([[maybe_unused]] entityx::EntityManager& entities,
+		[[maybe_unused]] entityx::EventManager& events,
+		[[maybe_unused]] entityx::TimeDelta dt) final {
+		for (SDL_Event event; SDL_PollEvent(&event);) {
+			switch (event.type) {
+			case SDL_KEYUP:
+				if (auto key = event.key; key.repeat == 0)
+					events.emit<KeyUpEvent>(key.keysym);
+				break;
+			case SDL_KEYDOWN:
+				if (auto key = event.key; key.repeat == 0)
+					events.emit<KeyDownEvent>(key.keysym);
+				break;
+			default:
+				break;
+			}
+		}
+	}
+};
+
+#endif // INPUT_HPP_
+