init config opt system w/ 3 types and description support

src/ui/elements/ElementDescription.cpp

@@ -0,0 +1,61 @@
+
+#include "ElementDescription.h"
+#include "librecomp/config_store.hpp"
+#include "../config_options/ConfigRegistry.h"
+#include <string>
+#include <RmlUi/Core/ElementDocument.h>
+#include <RmlUi/Core/ElementText.h>
+
+using json = nlohmann::json;
+
+namespace recompui {
+
+static const std::string cls_base = "config-description"; 
+static const std::string cls_contents = cls_base + "__contents"; 
+
+static const std::string contents_id = cls_base + "__contents-text";
+
+static const std::string default_contents = ""; 
+
+ElementDescription::ElementDescription(const Rml::String& tag) : Rml::Element(tag)
+{
+    SetAttribute("recomp-store-element", true);
+    Rml::ElementDocument *doc = GetOwnerDocument();
+
+    SetClass(cls_base, true);
+    {
+        Rml::Element *p_el = AppendChild(doc->CreateElement("p"));
+        p_el->SetClass(cls_contents, true);
+        p_el->SetId(contents_id);
+    }
+}
+
+ElementDescription::~ElementDescription()
+{
+}
+
+void ElementDescription::update_text(const std::string& text) {
+    auto *p_el = GetElementById(contents_id);
+    p_el->SetInnerRML(text);
+    DirtyLayout();
+}
+
+void ElementDescription::OnAttributeChange(const Rml::ElementAttributes& changed_attributes)
+{
+	// Call through to the base element's OnAttributeChange().
+	Rml::Element::OnAttributeChange(changed_attributes);
+
+    auto config_store_key_attr = changed_attributes.find("recomp-data");
+    if (config_store_key_attr != changed_attributes.end() && config_store_key_attr->second.GetType() == Rml::Variant::STRING) {
+        config_key = config_store_key_attr->second.Get<Rml::String>();
+
+        try {
+            auto value = recomp::get_config_store_value<std::string>("translations/" + config_key + ":description");
+            update_text(value);
+        } catch (const std::runtime_error& e) {
+            update_text(default_contents);
+        }
+    }
+}
+
+} // namespace Rml