IAEngine/Src/Editor/imp/cpp/Editor.cpp

// IAEngine: 2D Game Engine by IA
// Copyright (C) 2025 IASoft (PVT) LTD (oss@iasoft.dev)
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

#include <Editor.hpp>

#include <IAEngine/IAEngine.hpp>
#include <RenderCore/RenderCore.hpp>
#include <SDL3/SDL.h>

#include <Vendor/imgui/backends/imgui_impl_sdl3.h>
#include <Vendor/imgui/backends/imgui_impl_sdlgpu3.h>

#include <UI/UI.hpp>

#include <UI/View/Asset.hpp>

#include <LogoIcon.hpp>

namespace ia::iae
{
    EXTERN UINT8 DATA_TTF_FONTAWESOME7FREESOLID900[];
    EXTERN SIZE_T SIZE_TTF_FONTAWESOME7FREESOLID900;

    EXTERN SDL_Window *g_windowHandle;

    Editor Editor::s_instance{};

    ImDrawData *g_imDrawData{};
    IVec2 g_windowExtent{800, 600};

    VOID Editor::LoadProject(IN CONST String &directory)
    {
        m_activeProject = Project::Load(directory);
    }

    VOID Editor::OpenAsset(IN Path path)
    {
        UI::GetAssetView()->Open(path);
        UI::FocusAssetView();
    }

    INT32 Editor::Run(IN INT32 argc, IN PCCHAR argv[])
    {
        if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_GAMEPAD))
            THROW_UNKNOWN("Failed to intialize SDL: ", SDL_GetError());

        if (!(g_windowHandle = SDL_CreateWindow("IAEngine", g_windowExtent.x, g_windowExtent.y, SDL_WINDOW_RESIZABLE)))
            THROW_UNKNOWN("Failed to create the SDL window: ", SDL_GetError());

        LoadProject(".");

        SDL_SetWindowPosition(g_windowHandle, m_activeProject->WindowPosition().x, m_activeProject->WindowPosition().y);
        SDL_MaximizeWindow(g_windowHandle);
        SDL_GetWindowSizeInPixels(g_windowHandle, &g_windowExtent.x, &g_windowExtent.y);

        SDL_Surface *iconSurface = SDL_CreateSurface(LOGO_ICON_WIDTH, LOGO_ICON_HEIGHT, SDL_PIXELFORMAT_RGBA32);
        if (iconSurface)
        {
            for (UINT32 i = 0; i < LOGO_ICON_WIDTH * LOGO_ICON_HEIGHT * 4; i += 4)
            {
                STATIC UINT32 p{0xFFFFFFFF};
                const auto pixel = ((PUINT8) &p);
                const auto pixels = (PUINT8) iconSurface->pixels;
                LOGO_ICON_GET_PIXEL(LOGO_ICON_DATA, pixel);
                pixels[i + 0] = pixel[0];
                pixels[i + 1] = pixel[1];
                pixels[i + 2] = pixel[2];
                pixels[i + 3] = 0xFF;
            }

            SDL_SetWindowIcon(g_windowHandle, iconSurface);
            SDL_DestroySurface(iconSurface);
        }

        SDL_SetWindowTitle(g_windowHandle, BuildString("IAEngine - ", m_activeProject->Name()).c_str());

        RDC::Initialize(g_windowExtent, g_windowHandle, true);

        const auto mainScale = SDL_GetDisplayContentScale(SDL_GetPrimaryDisplay());

        IMGUI_CHECKVERSION();
        ImGui::CreateContext();
        auto &imGUIIO = ImGui::GetIO();
        imGUIIO.IniFilename = nullptr;
        imGUIIO.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
        imGUIIO.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;

        ImGuiStyle &style = ImGui::GetStyle();
        style.ScaleAllSizes(mainScale);
        style.FontScaleDpi = mainScale;

        ImGui_ImplSDLGPU3_InitInfo initInfo{.Device = RDC_Device::GetHandle(),
                                            .ColorTargetFormat = RDC_Device::GetSwapchainTextureFormat(),
                                            .PresentMode = SDL_GPU_PRESENTMODE_VSYNC};
        ImGui_ImplSDL3_InitForSDLGPU(g_windowHandle);
        ImGui_ImplSDLGPU3_Init(&initInfo);

        ImFontConfig fontConfig;
        fontConfig.MergeMode = true;
        fontConfig.PixelSnapH = true;
        fontConfig.FontDataOwnedByAtlas = false;
        fontConfig.GlyphOffset.y = 1.5f;
        fontConfig.SizePixels = 12.0f;
        static const ImWchar icon_ranges[] = {ICON_MIN_FA, ICON_MAX_FA, 0};

        imGUIIO.Fonts->AddFontDefault();
        imGUIIO.Fonts->AddFontFromMemoryTTF((PVOID) DATA_TTF_FONTAWESOME7FREESOLID900,
                                            SIZE_TTF_FONTAWESOME7FREESOLID900, 0.0f, &fontConfig, icon_ranges);
        imGUIIO.Fonts->Build();

        UI::Initialize();

        SDL_Event event{};
        while (true)
        {
            SDL_PollEvent(&event);
            if (event.type == SDL_EVENT_QUIT)
                break;
            UI::ProcessEvent(&event);
            UI::Update();
            ImGui_ImplSDL3_ProcessEvent(&event);

            ImGui_ImplSDLGPU3_NewFrame();
            ImGui_ImplSDL3_NewFrame();
            ImGui::NewFrame();

            UI::Draw();

            ImGui::Render();

            STATIC SDL_GPURenderPass *ActiveRenderPass{};
            STATIC SDL_GPUCommandBuffer *ActiveCommandBuffer{};
            STATIC SDL_GPUColorTargetInfo ActiveColorTargetInfo{.clear_color = SDL_FColor{0.0f, 0.0f, 0.0f, 1.0f},
                                                                .load_op = SDL_GPU_LOADOP_CLEAR,
                                                                .store_op = SDL_GPU_STOREOP_STORE};

            if (!(ActiveCommandBuffer = SDL_AcquireGPUCommandBuffer(RDC_Device::GetHandle())))
                THROW_UNKNOWN("Failed to acquire SDL GPU command buffer: ", SDL_GetError());

            g_imDrawData = ImGui::GetDrawData();
            ImGui_ImplSDLGPU3_PrepareDrawData(g_imDrawData, ActiveCommandBuffer);

            SDL_GPUTexture *swapChainTexture{};
            if (!SDL_WaitAndAcquireGPUSwapchainTexture(ActiveCommandBuffer, g_windowHandle, &swapChainTexture, nullptr,
                                                       nullptr))
                THROW_UNKNOWN("Failed to acquire SDL GPU Swapchain texture: ", SDL_GetError());

            ActiveColorTargetInfo.texture = swapChainTexture;
            ActiveColorTargetInfo.clear_color = SDL_FColor{0.3f, 0.3f, 0.3f, 1.0f};
            ActiveRenderPass = SDL_BeginGPURenderPass(ActiveCommandBuffer, &ActiveColorTargetInfo, 1, nullptr);
            ImGui_ImplSDLGPU3_RenderDrawData(g_imDrawData, ActiveCommandBuffer, ActiveRenderPass);

            SDL_EndGPURenderPass(ActiveRenderPass);

            SDL_SubmitGPUCommandBuffer(ActiveCommandBuffer);

            RDC_Device::WaitForIdle();
        }

        IVec2 currentWindowPosition{};
        SDL_GetWindowPosition(g_windowHandle, &currentWindowPosition.x, &currentWindowPosition.y);
        m_activeProject->WindowPosition() = currentWindowPosition;
        m_activeProject->Update();

        UI::Terminate();

        ImGui_ImplSDL3_Shutdown();
        ImGui_ImplSDLGPU3_Shutdown();
        ImGui::DestroyContext();

        SDL_DestroyWindow(g_windowHandle);

        return 0;
    }
} // namespace ia::iae