#include "XCUIBackend/XCUIEditorFontSetup.h"

#include <imgui.h>

namespace XCEngine {
namespace Editor {
namespace XCUIBackend {

namespace {

constexpr float kUiFontSize = 18.0f;
constexpr const char* kPrimaryUiFontPath = "C:/Windows/Fonts/segoeui.ttf";
constexpr const char* kChineseFallbackFontPath = "C:/Windows/Fonts/msyh.ttc";

bool BuildDefaultXCUIEditorFontAtlas(::ImFontAtlas& atlas, ::ImFont*& outDefaultFont) {
    outDefaultFont = nullptr;
    atlas.Clear();

    ImFontConfig baseConfig = {};
    baseConfig.OversampleH = 2;
    baseConfig.OversampleV = 1;
    baseConfig.PixelSnapH = true;

    outDefaultFont = atlas.AddFontFromFileTTF(
        kPrimaryUiFontPath,
        kUiFontSize,
        &baseConfig,
        atlas.GetGlyphRangesDefault());

    if (outDefaultFont != nullptr) {
        ImFontConfig mergeConfig = baseConfig;
        mergeConfig.MergeMode = true;
        mergeConfig.PixelSnapH = true;
        atlas.AddFontFromFileTTF(
            kChineseFallbackFontPath,
            kUiFontSize,
            &mergeConfig,
            atlas.GetGlyphRangesChineseSimplifiedCommon());
    } else {
        outDefaultFont = atlas.AddFontFromFileTTF(
            kChineseFallbackFontPath,
            kUiFontSize,
            &baseConfig,
            atlas.GetGlyphRangesChineseSimplifiedCommon());
    }

    if (outDefaultFont == nullptr) {
        ImFontConfig fallbackConfig = baseConfig;
        fallbackConfig.SizePixels = kUiFontSize;
        outDefaultFont = atlas.AddFontDefault(&fallbackConfig);
    }

    return outDefaultFont != nullptr;
}

} // namespace

bool ConfigureDefaultXCUIEditorFontsForCurrentContext() {
    ImGuiIO& io = ImGui::GetIO();
    ImFont* uiFont = nullptr;
    if (!BuildDefaultXCUIEditorFontAtlas(*io.Fonts, uiFont)) {
        return false;
    }

    io.FontDefault = uiFont;
    return io.FontDefault != nullptr;
}

} // namespace XCUIBackend
} // namespace Editor
} // namespace XCEngine