#include "Bootstrap/Application.h"
#include "Bootstrap/ApplicationBootstrapSupport.h"

#include "Platform/Win32/EditorWindow.h"
#include "Platform/Win32/EditorWindowManager.h"

#include <Platform/Win32/WindowMessageDispatcher.h>

namespace XCEngine::UI::Editor {

using namespace BootstrapSupport;

namespace {

void TryEnableNonClientDpiScaling(HWND hwnd) {
    if (hwnd == nullptr) {
        return;
    }

    const HMODULE user32 = GetModuleHandleW(L"user32.dll");
    if (user32 == nullptr) {
        return;
    }

    using EnableNonClientDpiScalingFn = BOOL(WINAPI*)(HWND);
    const auto enableNonClientDpiScaling =
        reinterpret_cast<EnableNonClientDpiScalingFn>(
            GetProcAddress(user32, "EnableNonClientDpiScaling"));
    if (enableNonClientDpiScaling != nullptr) {
        enableNonClientDpiScaling(hwnd);
    }
}

Application* GetApplicationFromWindowUserData(HWND hwnd) {
    return reinterpret_cast<Application*>(GetWindowLongPtrW(hwnd, GWLP_USERDATA));
}

} // namespace

bool Application::RegisterWindowClass() {
    WNDCLASSEXW windowClass = {};
    windowClass.cbSize = sizeof(windowClass);
    windowClass.style = CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
    windowClass.lpfnWndProc = &Application::WndProc;
    windowClass.cbClsExtra = 0;
    windowClass.cbWndExtra = 0;
    windowClass.hInstance = m_hInstance;
    windowClass.hCursor = LoadCursorW(nullptr, IDC_ARROW);
    windowClass.hbrBackground = nullptr;
    windowClass.lpszMenuName = nullptr;
    windowClass.hIcon = static_cast<HICON>(
        LoadImageW(
            m_hInstance,
            MAKEINTRESOURCEW(IDI_APP_ICON),
            IMAGE_ICON,
            0,
            0,
            LR_DEFAULTSIZE));
    windowClass.hIconSm = static_cast<HICON>(
        LoadImageW(
            m_hInstance,
            MAKEINTRESOURCEW(IDI_APP_ICON_SMALL),
            IMAGE_ICON,
            GetSystemMetrics(SM_CXSMICON),
            GetSystemMetrics(SM_CYSMICON),
            LR_DEFAULTCOLOR));
    windowClass.lpszClassName = kWindowClassName;
    m_windowClassAtom = RegisterClassExW(&windowClass);
    if (m_windowClassAtom == 0) {
        AppendUIEditorRuntimeTrace("app", "window class registration failed");
        return false;
    }

    return true;
}

LRESULT CALLBACK Application::WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
    if (message == WM_NCCREATE) {
        TryEnableNonClientDpiScaling(hwnd);
        const auto* createStruct = reinterpret_cast<const CREATESTRUCTW*>(lParam);
        Application* application =
            createStruct != nullptr
                ? reinterpret_cast<Application*>(createStruct->lpCreateParams)
                : nullptr;
        SetWindowLongPtrW(hwnd, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(application));
        if (application != nullptr && application->m_windowManager != nullptr) {
            application->m_windowManager->HandlePendingNativeWindowCreated(hwnd);
        }
        return TRUE;
    }

    Application* application = GetApplicationFromWindowUserData(hwnd);
    App::EditorWindow* window =
        application != nullptr && application->m_windowManager != nullptr
        ? application->m_windowManager->FindWindow(hwnd)
        : nullptr;
    LRESULT dispatcherResult = 0;
    if (application != nullptr &&
        window != nullptr &&
        Host::WindowMessageDispatcher::TryDispatch(
            hwnd,
            *application,
            *window,
            message,
            wParam,
            lParam,
            dispatcherResult)) {
        return dispatcherResult;
    }

    return DefWindowProcW(hwnd, message, wParam, lParam);
}

} // namespace XCEngine::UI::Editor