// ImGui - standalone example application for Glfw + OpenGL 2, using fixed pipeline
// If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.

#include <imgui.h>
#include "imgui_impl_glfw.h"
#include <stdio.h>
#include <GLFW/glfw3.h>
#include <vector>

static void error_callback(int error, const char* description)
{
    fprintf(stderr, "Error %d: %s\n", error, description);
}

std::vector<float> foos;

int main(int, char**)
{
    foos.push_back(0.3);
    
    // Setup window
    glfwSetErrorCallback(error_callback);
    if (!glfwInit())
        return 1;
    GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGui OpenGL2 example", NULL, NULL);
    glfwMakeContextCurrent(window);

    // Setup ImGui binding
    ImGui_ImplGlfw_Init(window, true);

    bool show_test_window = true;
    bool show_another_window = false;
    ImVec4 clear_color = ImColor(114, 144, 154);

    // Main loop
    while (!glfwWindowShouldClose(window))
    {
        glfwPollEvents();
        ImGui_ImplGlfw_NewFrame();

        // 1. Show a simple window
        // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"
        {
            static float f = 0.0f;
            ImGui::Text("Hello, world!");
            ImGui::SliderFloat("float", &f, 0.0f, 1.0f);

            // fails
            /*
            for(auto s : foos) {
                ImGui::SliderFloat("float x", &s, 0.0f, 1.0f);
            }
            */
            
            
            // fails
            ///*
            for(float s : foos) {
                ImGui::SliderFloat("float x", &s, 0.0f, 1.0f);
            }
            //*/

            // works
            /*
            for(auto &s : foos) {
                ImGui::SliderFloat("float x", &s, 0.0f, 1.0f);
            }
            */

            // works
            /*
            for(float &s : foos) {
                ImGui::SliderFloat("float x", &s, 0.0f, 1.0f);
            }
            */
        }

        // Rendering
        int display_w, display_h;
        glfwGetFramebufferSize(window, &display_w, &display_h);
        glViewport(0, 0, display_w, display_h);
        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
        glClear(GL_COLOR_BUFFER_BIT);
        ImGui::Render();
        glfwSwapBuffers(window);
    }

    // Cleanup
    ImGui_ImplGlfw_Shutdown();
    glfwTerminate();

    return 0;
}