the shortcut

src/graphics/ui/elements/Menu.cpp

@@ -0,0 +1,93 @@
+#include "Menu.hpp"
+
+#include <stdexcept>
+
+using namespace gui;
+
+Menu::Menu() : Container(glm::vec2(1)){
+}
+
+bool Menu::has(const std::string& name) {
+    return pages.find(name) != pages.end() ||
+           pageSuppliers.find(name) != pageSuppliers.end();
+}
+
+void Menu::addPage(std::string name, std::shared_ptr<UINode> panel) {
+    pages[name] = Page{name, panel};
+}
+
+void Menu::addSupplier(std::string name, supplier<std::shared_ptr<UINode>> pageSupplier) {
+    pageSuppliers[name] = pageSupplier;
+}
+
+std::shared_ptr<UINode> Menu::fetchPage(const std::string& name) {
+    auto found = pages.find(name);
+    if (found == pages.end()) {
+        auto supplier = pageSuppliers.find(name);
+        if (supplier == pageSuppliers.end()) {
+            if (pagesLoader) {
+                return pagesLoader(name);
+            }
+            return nullptr;
+        } else {
+            return supplier->second();
+            // supplied pages caching is not implemented
+        }
+    } else {
+        return found->second.panel;
+    }
+}
+
+void Menu::setPage(std::string name, bool history) {
+    Page page {name, fetchPage(name)};
+    if (page.panel == nullptr) {
+        throw std::runtime_error("no page found");
+    }
+    setPage(page, history);
+}
+
+void Menu::setPage(Page page, bool history) {
+    if (current.panel) {
+        Container::remove(current.panel);
+    }
+    if (history) {
+        pageStack.push(current);
+    }
+    current = page;
+    Container::add(current.panel);
+    setSize(current.panel->getSize());
+}
+
+void Menu::back() {
+    if (pageStack.empty())
+        return;
+    Page page = pageStack.top();
+    pageStack.pop();
+    
+    auto updated = fetchPage(page.name);
+    if (updated) {
+        page.panel = updated;
+    }
+
+    setPage(page, false);
+}
+
+void Menu::setPageLoader(page_loader_func loader) {
+    pagesLoader = loader;
+}
+
+Page& Menu::getCurrent() {
+    return current;
+}
+
+void Menu::clearHistory() {
+    pageStack = std::stack<Page>();
+}
+
+void Menu::reset() {
+    clearHistory();
+    if (current.panel) {
+        Container::remove(current.panel);
+        current = Page{"", nullptr};
+    }
+}