Simulation GUI: Refactor ini saving (#2291)

simulation/halsim_gui/src/main/native/include/IniSaver.h

@@ -0,0 +1,47 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <imgui.h>
+#include <imgui_internal.h>
+#include <wpi/DenseMap.h>
+
+namespace halsimgui {
+
+template <typename Info>
+class IniSaver {
+ public:
+  explicit IniSaver(const char* typeName) : m_typeName(typeName) {}
+  void Initialize();
+
+  // pass through useful functions to map
+  Info& operator[](int index) { return m_map[index]; }
+
+  auto begin() { return m_map.begin(); }
+  auto end() { return m_map.end(); }
+  auto find(int index) { return m_map.find(index); }
+
+  auto begin() const { return m_map.begin(); }
+  auto end() const { return m_map.end(); }
+  auto find(int index) const { return m_map.find(index); }
+
+ private:
+  static void* ReadOpen(ImGuiContext* ctx, ImGuiSettingsHandler* handler,
+                        const char* name);
+  static void ReadLine(ImGuiContext* ctx, ImGuiSettingsHandler* handler,
+                       void* entry, const char* lineStr);
+  static void WriteAll(ImGuiContext* ctx, ImGuiSettingsHandler* handler,
+                       ImGuiTextBuffer* out_buf);
+
+  const char* m_typeName;
+  wpi::DenseMap<int, Info> m_map;
+};
+
+}  // namespace halsimgui
+
+#include "IniSaver.inl"