#include "bookmouse.hpp"

#include <SDL_opengl.h>
#include <fud_array.hpp>

namespace bookmouse {

Bookmouse::Bookmouse() :
    m_sdlContext{}, m_mainWindow{m_sdlContext}, m_glContext{m_mainWindow},
    m_imgui{m_glContext, m_sdlContext, m_mainWindow}
{
    /*
     * Load Fonts
     *
     * - If no fonts are loaded, dear imgui will use the default
     *   font. You can also load multiple fonts and use
     *   ImGui::PushFont()/PopFont() to select them.
     * - AddFontFromFileTTF() will return the ImFont* so you can store
     *   it if you need to select the font among multiple.
     * - If the file cannot be loaded, the function will return a
     *   nullptr. Please handle those errors in your application
     *   (e.g. use an assertion, or display an error and quit).
     * - The fonts will be rasterized at a given size (w/
     *   oversampling) and stored into a texture when calling
     *   ImFontAtlas::Build()/GetTexDataAsXXXX(), which
     *   ImGui_ImplXXXX_NewFrame below will call.
     * - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to
     * - use Freetype for higher quality font rendering.
     * - Read 'docs/FONTS.md' for more instructions and details.
     * - Remember that in C/C++ if you want to include a backslash \
     *   in a string literal you need to write a double backslash \\ !
     * - Our Emscripten build process allows embedding fonts to be
     * - accessible at runtime from the "fonts/" folder. See
     *   Makefile.emscripten for details.
     * auto imguiIO = m_imgui.getIO();
     * imguiIO.Fonts->AddFontDefault();
     * imguiIO.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\segoeui.ttf", 18.0f);
     * imguiIO.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);
     * imguiIO.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
     * imguiIO.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);
     * ImFont* font = imguiIO.Fonts->AddFontFromFileTTF(
     *    "c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, nullptr,
     * io.Fonts->GetGlyphRangesJapanese()); IM_ASSERT(font != nullptr);
     */
}

int Bookmouse::run()
{
    while (m_running) {
        auto event = pollEvent();
        static_cast<void>(event);

        constexpr uint32_t delayMillis = 10;
        if (SDL_GetWindowFlags(m_mainWindow.window()) & SDL_WINDOW_MINIMIZED) {
            SDL_Delay(delayMillis);
            continue;
        }
        m_imgui.startFrame();
        updateState();
        renderFrame();
    }
    return 0;
}

SDL_Event Bookmouse::pollEvent()
{
    /*
     * Poll and handle events (inputs, window resize, etc.)
     * You can read the io.WantCaptureMouse, io.WantCaptureKeyboard
     * flags to tell if dear imgui wants to use your inputs.
     * - When io.WantCaptureMouse is true, do not dispatch mouse input
     *   data to your main application, or clear/overwrite your copy of
     *   the mouse data.
     * - When io.WantCaptureKeyboard is true, do not dispatch keyboard
     *   input data to your main application, or clear/overwrite your
     *   copy of the keyboard data.
     * Generally you may always pass all inputs to dear imgui, and
     * hide them from your application based on those two flags.
     */
    SDL_Event event{};
    while (SDL_PollEvent(&event)) {
        static_cast<void>(m_imgui.processEvent(event));
        if (event.type == SDL_QUIT) {
            m_running = false;
        }
        if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE &&
            event.window.windowID == SDL_GetWindowID(m_mainWindow.window())) {
            m_running = false;
        }
    }
    return event;
}

void Bookmouse::updateState()
{
    bool my_tool_active{true};
    ImGui::Begin("My First Tool", &my_tool_active, ImGuiWindowFlags_MenuBar);
    if (ImGui::BeginMenuBar()) {
        if (ImGui::BeginMenu("File")) {
            if (ImGui::MenuItem("Open..", "Ctrl+O")) { /* Do stuff */
            }
            if (ImGui::MenuItem("Save", "Ctrl+S")) { /* Do stuff */
            }
            if (ImGui::MenuItem("Close", "Ctrl+W")) {
                my_tool_active = false;
            }
            ImGui::EndMenu();
        }
        ImGui::EndMenuBar();
    }

    // Edit a color stored as 4 floats
    fud::Array<float, 4> my_color{};
    ImGui::ColorEdit4("Color", my_color.data());

    // Generate samples and plot them
    float samples[100];
    for (int idx = 0; idx < 100; idx++) {
        auto num = static_cast<float>(idx);
        auto time = static_cast<float>(ImGui::GetTime());
        samples[idx] = sinf(num * 0.2f + time * 1.5f);
    }
    ImGui::PlotLines("Samples", samples, 100);

    // Display contents in a scrolling region
    ImGui::TextColored(ImVec4(1, 1, 0, 1), "Important Stuff");
    ImGui::BeginChild("Scrolling");
    for (int n = 0; n < 50; n++)
        ImGui::Text("%04d: Some text", n);
    ImGui::EndChild();
    ImGui::End();
}

void Bookmouse::renderFrame()
{
    ImGui::Render();
    const auto& imguiIO = m_imgui.getIO();
    glViewport(0, 0, static_cast<int>(imguiIO.DisplaySize.x), static_cast<int>(imguiIO.DisplaySize.y));
    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
    glClearColor(
        clear_color.x * clear_color.w,
        clear_color.y * clear_color.w,
        clear_color.z * clear_color.w,
        clear_color.w);
    glClear(GL_COLOR_BUFFER_BIT);
    m_imgui.render();
}

} // namespace bookmouse