1 files changed, 107 insertions, 0 deletions
diff --git a/src/frontend.hpp b/src/frontend.hpp
new file mode 100644
index 00000000..b0861906
--- /dev/null
+++ b/src/frontend.hpp
@@ -0,0 +1,107 @@
+#pragma once
+
+#include "frontend_fwd.hpp"
+
+#include <string_view>
+
+#include "h-basic.hpp"
+
+/**
+ * User interface operations supported by the front end.
+ */
+class Frontend {
+
+public:
+	/**
+	 * Result polling/waiting for an event.
+	 */
+	enum class event_result_t {
+		SUCCESS,
+		FAILURE,
+	};
+
+	/**
+	 * Initialize the underlying user interface element.
+	 */
+	virtual void init() = 0;
+
+	/**
+	 * Destroy the underlying user interface element.
+	 */
+	virtual void nuke() = 0;
+
+	/**
+	 * Poll or wait for event and process it.
+	 */
+	virtual void process_event(bool wait) = 0;
+
+	/**
+	 * Does this user interface draw its own cursor?
+	 *
+	 * The return value is assumed to be constant over the
+	 * lifetime of the user interface.
+	 */
+	virtual bool soft_cursor() const = 0;
+
+	/**
+	 * Does this user interface have an "icky" lower right corner,
+	 * i.e. does it _not_ support putting the cursor in that corner?
+	 *
+	 * The return value is assumed to be constant over the
+	 * lifetime of the user interface.
+	 */
+	virtual bool icky_corner() const = 0;
+
+	/**
+	 * Flush any pending events.
+	 */
+	virtual void flush_events() = 0;
+
+	/**
+	 * Process any pending events.
+	 */
+	virtual void process_queued_events() = 0;
+
+	/**
+	 * Clear contents of the user interface.
+	 */
+	virtual void clear() = 0;
+
+	/**
+	 * Flush pending output.
+	 */
+	virtual void flush_output() = 0;
+
+	/**
+	 * Make a noise, e.g. a system beep or similar.
+	 */
+	virtual void noise() = 0;
+
+	/**
+	 * React to changes generated by the game, e.g. window
+	 * size, or colors.
+	 */
+	virtual void react() = 0;
+
+	/**
+	 * Rename the main window.
+	 */
+	virtual void rename_main_window(std::string_view) = 0;
+
+	/**
+	 * Draw the cursor at position x, y.
+	 */
+	virtual void draw_cursor(int x, int y) = 0;
+
+	/**
+	 * Draw the given text string s at position x, y
+	 * using attributes a.
+	 */
+	virtual void draw_text(int x, int y, int n, byte a, const char *s) = 0;
+
+	/**
+	 * Destroy.
+	 */
+	virtual ~Frontend() = default;
+
+};