initial commit

src/page_manager.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include "page.h"
+#include <memory>
+#include <vector>
+
+struct AppState;
+
+class PageManager {
+public:
+    PageManager() = default;
+
+    void push(AppState& state, std::unique_ptr<Page> page);
+    void pop(AppState& state);
+    void popToRoot(AppState& state);
+    void replace(AppState& state, std::unique_ptr<Page> page);
+
+    Page* current() const;
+    std::size_t depth() const;
+
+    void handleEvent(const SDL_Event& event);
+    void update(float dt);
+    void render(SDL_Renderer* renderer);
+
+private:
+    std::vector<std::unique_ptr<Page>> stack_;
+};