#include "Application.h"

#include <Host/WindowMessageDispatcher.h>

#include <XCEditor/Foundation/UIEditorRuntimeTrace.h>
#include <XCEditor/Foundation/UIEditorTheme.h>

#include <XCEngine/Input/InputTypes.h>
#include <XCEngine/UI/DrawData.h>

#include <algorithm>
#include <cctype>
#include <cstdlib>
#include <sstream>
#include <string>

#include <shellscalingapi.h>

#ifndef XCUIEDITOR_REPO_ROOT
#define XCUIEDITOR_REPO_ROOT "."
#endif

namespace XCEngine::UI::Editor {

namespace {

using ::XCEngine::Input::KeyCode;
using ::XCEngine::UI::UIColor;
using ::XCEngine::UI::UIDrawData;
using ::XCEngine::UI::UIDrawList;
using ::XCEngine::UI::UIInputEvent;
using ::XCEngine::UI::UIInputEventType;
using ::XCEngine::UI::UIPoint;
using ::XCEngine::UI::UIPointerButton;
using ::XCEngine::UI::UIRect;

constexpr const wchar_t* kWindowClassName = L"XCEditorShellHost";
constexpr const wchar_t* kWindowTitle = L"Main Scene * - Main.xx - XCEngine Editor";
constexpr UINT kDefaultDpi = 96u;
constexpr float kBaseDpiScale = 96.0f;

bool ResolveVerboseRuntimeTraceEnabled() {
    wchar_t buffer[8] = {};
    const DWORD length = GetEnvironmentVariableW(
        L"XCUIEDITOR_VERBOSE_TRACE",
        buffer,
        static_cast<DWORD>(std::size(buffer)));
    return length > 0u && buffer[0] != L'0';
}

UINT QuerySystemDpi() {
    HDC screenDc = GetDC(nullptr);
    if (screenDc == nullptr) {
        return kDefaultDpi;
    }

    const int dpiX = GetDeviceCaps(screenDc, LOGPIXELSX);
    ReleaseDC(nullptr, screenDc);
    return dpiX > 0 ? static_cast<UINT>(dpiX) : kDefaultDpi;
}

UINT QueryWindowDpi(HWND hwnd) {
    if (hwnd != nullptr) {
        const HMODULE user32 = GetModuleHandleW(L"user32.dll");
        if (user32 != nullptr) {
            using GetDpiForWindowFn = UINT(WINAPI*)(HWND);
            const auto getDpiForWindow =
                reinterpret_cast<GetDpiForWindowFn>(GetProcAddress(user32, "GetDpiForWindow"));
            if (getDpiForWindow != nullptr) {
                const UINT dpi = getDpiForWindow(hwnd);
                if (dpi != 0u) {
                    return dpi;
                }
            }
        }
    }

    return QuerySystemDpi();
}

void EnableDpiAwareness() {
    const HMODULE user32 = GetModuleHandleW(L"user32.dll");
    if (user32 != nullptr) {
        using SetProcessDpiAwarenessContextFn = BOOL(WINAPI*)(DPI_AWARENESS_CONTEXT);
        const auto setProcessDpiAwarenessContext =
            reinterpret_cast<SetProcessDpiAwarenessContextFn>(
                GetProcAddress(user32, "SetProcessDpiAwarenessContext"));
        if (setProcessDpiAwarenessContext != nullptr) {
            if (setProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2)) {
                return;
            }
            if (GetLastError() == ERROR_ACCESS_DENIED) {
                return;
            }
            if (setProcessDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE)) {
                return;
            }
            if (GetLastError() == ERROR_ACCESS_DENIED) {
                return;
            }
        }
    }

    const HMODULE shcore = LoadLibraryW(L"shcore.dll");
    if (shcore != nullptr) {
        using SetProcessDpiAwarenessFn = HRESULT(WINAPI*)(PROCESS_DPI_AWARENESS);
        const auto setProcessDpiAwareness =
            reinterpret_cast<SetProcessDpiAwarenessFn>(
                GetProcAddress(shcore, "SetProcessDpiAwareness"));
        if (setProcessDpiAwareness != nullptr) {
            const HRESULT hr = setProcessDpiAwareness(PROCESS_PER_MONITOR_DPI_AWARE);
            FreeLibrary(shcore);
            if (SUCCEEDED(hr) || hr == E_ACCESSDENIED) {
                return;
            }
        } else {
            FreeLibrary(shcore);
        }
    }

    if (user32 != nullptr) {
        using SetProcessDPIAwareFn = BOOL(WINAPI*)();
        const auto setProcessDPIAware =
            reinterpret_cast<SetProcessDPIAwareFn>(GetProcAddress(user32, "SetProcessDPIAware"));
        if (setProcessDPIAware != nullptr) {
            setProcessDPIAware();
        }
    }
}

std::string TruncateText(const std::string& text, std::size_t maxLength) {
    if (text.size() <= maxLength) {
        return text;
    }

    if (maxLength <= 3u) {
        return text.substr(0u, maxLength);
    }

    return text.substr(0u, maxLength - 3u) + "...";
}

bool IsAutoCaptureOnStartupEnabled() {
    const char* value = std::getenv("XCUI_AUTO_CAPTURE_ON_STARTUP");
    if (value == nullptr || value[0] == '\0') {
        return false;
    }

    std::string normalized = value;
    std::transform(
        normalized.begin(),
        normalized.end(),
        normalized.begin(),
        [](unsigned char character) {
            return static_cast<char>(std::tolower(character));
        });
    return normalized != "0" &&
        normalized != "false" &&
        normalized != "off" &&
        normalized != "no";
}

std::int32_t MapVirtualKeyToUIKeyCode(WPARAM wParam) {
    switch (wParam) {
    case 'A': return static_cast<std::int32_t>(KeyCode::A);
    case 'B': return static_cast<std::int32_t>(KeyCode::B);
    case 'C': return static_cast<std::int32_t>(KeyCode::C);
    case 'D': return static_cast<std::int32_t>(KeyCode::D);
    case 'E': return static_cast<std::int32_t>(KeyCode::E);
    case 'F': return static_cast<std::int32_t>(KeyCode::F);
    case 'G': return static_cast<std::int32_t>(KeyCode::G);
    case 'H': return static_cast<std::int32_t>(KeyCode::H);
    case 'I': return static_cast<std::int32_t>(KeyCode::I);
    case 'J': return static_cast<std::int32_t>(KeyCode::J);
    case 'K': return static_cast<std::int32_t>(KeyCode::K);
    case 'L': return static_cast<std::int32_t>(KeyCode::L);
    case 'M': return static_cast<std::int32_t>(KeyCode::M);
    case 'N': return static_cast<std::int32_t>(KeyCode::N);
    case 'O': return static_cast<std::int32_t>(KeyCode::O);
    case 'P': return static_cast<std::int32_t>(KeyCode::P);
    case 'Q': return static_cast<std::int32_t>(KeyCode::Q);
    case 'R': return static_cast<std::int32_t>(KeyCode::R);
    case 'S': return static_cast<std::int32_t>(KeyCode::S);
    case 'T': return static_cast<std::int32_t>(KeyCode::T);
    case 'U': return static_cast<std::int32_t>(KeyCode::U);
    case 'V': return static_cast<std::int32_t>(KeyCode::V);
    case 'W': return static_cast<std::int32_t>(KeyCode::W);
    case 'X': return static_cast<std::int32_t>(KeyCode::X);
    case 'Y': return static_cast<std::int32_t>(KeyCode::Y);
    case 'Z': return static_cast<std::int32_t>(KeyCode::Z);
    case '0': return static_cast<std::int32_t>(KeyCode::Zero);
    case '1': return static_cast<std::int32_t>(KeyCode::One);
    case '2': return static_cast<std::int32_t>(KeyCode::Two);
    case '3': return static_cast<std::int32_t>(KeyCode::Three);
    case '4': return static_cast<std::int32_t>(KeyCode::Four);
    case '5': return static_cast<std::int32_t>(KeyCode::Five);
    case '6': return static_cast<std::int32_t>(KeyCode::Six);
    case '7': return static_cast<std::int32_t>(KeyCode::Seven);
    case '8': return static_cast<std::int32_t>(KeyCode::Eight);
    case '9': return static_cast<std::int32_t>(KeyCode::Nine);
    case VK_SPACE: return static_cast<std::int32_t>(KeyCode::Space);
    case VK_TAB: return static_cast<std::int32_t>(KeyCode::Tab);
    case VK_RETURN: return static_cast<std::int32_t>(KeyCode::Enter);
    case VK_ESCAPE: return static_cast<std::int32_t>(KeyCode::Escape);
    case VK_SHIFT: return static_cast<std::int32_t>(KeyCode::LeftShift);
    case VK_CONTROL: return static_cast<std::int32_t>(KeyCode::LeftCtrl);
    case VK_MENU: return static_cast<std::int32_t>(KeyCode::LeftAlt);
    case VK_UP: return static_cast<std::int32_t>(KeyCode::Up);
    case VK_DOWN: return static_cast<std::int32_t>(KeyCode::Down);
    case VK_LEFT: return static_cast<std::int32_t>(KeyCode::Left);
    case VK_RIGHT: return static_cast<std::int32_t>(KeyCode::Right);
    case VK_HOME: return static_cast<std::int32_t>(KeyCode::Home);
    case VK_END: return static_cast<std::int32_t>(KeyCode::End);
    case VK_PRIOR: return static_cast<std::int32_t>(KeyCode::PageUp);
    case VK_NEXT: return static_cast<std::int32_t>(KeyCode::PageDown);
    case VK_DELETE: return static_cast<std::int32_t>(KeyCode::Delete);
    case VK_BACK: return static_cast<std::int32_t>(KeyCode::Backspace);
    case VK_F1: return static_cast<std::int32_t>(KeyCode::F1);
    case VK_F2: return static_cast<std::int32_t>(KeyCode::F2);
    case VK_F3: return static_cast<std::int32_t>(KeyCode::F3);
    case VK_F4: return static_cast<std::int32_t>(KeyCode::F4);
    case VK_F5: return static_cast<std::int32_t>(KeyCode::F5);
    case VK_F6: return static_cast<std::int32_t>(KeyCode::F6);
    case VK_F7: return static_cast<std::int32_t>(KeyCode::F7);
    case VK_F8: return static_cast<std::int32_t>(KeyCode::F8);
    case VK_F9: return static_cast<std::int32_t>(KeyCode::F9);
    case VK_F10: return static_cast<std::int32_t>(KeyCode::F10);
    case VK_F11: return static_cast<std::int32_t>(KeyCode::F11);
    case VK_F12: return static_cast<std::int32_t>(KeyCode::F12);
    default: return static_cast<std::int32_t>(KeyCode::None);
    }
}

bool IsRepeatKeyMessage(LPARAM lParam) {
    return (static_cast<unsigned long>(lParam) & (1ul << 30)) != 0ul;
}

std::filesystem::path GetExecutableDirectory() {
    std::vector<wchar_t> buffer(MAX_PATH);
    while (true) {
        const DWORD copied = ::GetModuleFileNameW(
            nullptr,
            buffer.data(),
            static_cast<DWORD>(buffer.size()));
        if (copied == 0u) {
            return std::filesystem::current_path().lexically_normal();
        }

        if (copied < buffer.size() - 1u) {
            return std::filesystem::path(std::wstring(buffer.data(), copied))
                .parent_path()
                .lexically_normal();
        }

        buffer.resize(buffer.size() * 2u);
    }
}

std::string DescribeInputEventType(const UIInputEvent& event) {
    switch (event.type) {
    case UIInputEventType::PointerMove: return "PointerMove";
    case UIInputEventType::PointerEnter: return "PointerEnter";
    case UIInputEventType::PointerLeave: return "PointerLeave";
    case UIInputEventType::PointerButtonDown: return "PointerDown";
    case UIInputEventType::PointerButtonUp: return "PointerUp";
    case UIInputEventType::PointerWheel: return "PointerWheel";
    case UIInputEventType::KeyDown: return "KeyDown";
    case UIInputEventType::KeyUp: return "KeyUp";
    case UIInputEventType::Character: return "Character";
    case UIInputEventType::FocusGained: return "FocusGained";
    case UIInputEventType::FocusLost: return "FocusLost";
    default: return "Unknown";
    }
}

std::string DescribeProjectPanelEvent(const App::ProductProjectPanel::Event& event) {
    std::ostringstream stream = {};
    switch (event.kind) {
    case App::ProductProjectPanel::EventKind::AssetSelected:
        stream << "AssetSelected";
        break;
    case App::ProductProjectPanel::EventKind::AssetSelectionCleared:
        stream << "AssetSelectionCleared";
        break;
    case App::ProductProjectPanel::EventKind::FolderNavigated:
        stream << "FolderNavigated";
        break;
    case App::ProductProjectPanel::EventKind::AssetOpened:
        stream << "AssetOpened";
        break;
    case App::ProductProjectPanel::EventKind::ContextMenuRequested:
        stream << "ContextMenuRequested";
        break;
    case App::ProductProjectPanel::EventKind::None:
    default:
        stream << "None";
        break;
    }

    stream << " source=";
    switch (event.source) {
    case App::ProductProjectPanel::EventSource::Tree:
        stream << "Tree";
        break;
    case App::ProductProjectPanel::EventSource::Breadcrumb:
        stream << "Breadcrumb";
        break;
    case App::ProductProjectPanel::EventSource::GridPrimary:
        stream << "GridPrimary";
        break;
    case App::ProductProjectPanel::EventSource::GridDoubleClick:
        stream << "GridDoubleClick";
        break;
    case App::ProductProjectPanel::EventSource::GridSecondary:
        stream << "GridSecondary";
        break;
    case App::ProductProjectPanel::EventSource::Background:
        stream << "Background";
        break;
    case App::ProductProjectPanel::EventSource::None:
    default:
        stream << "None";
        break;
    }

    if (!event.itemId.empty()) {
        stream << " item=" << event.itemId;
    }
    if (!event.displayName.empty()) {
        stream << " label=" << event.displayName;
    }
    return stream.str();
}

std::string DescribeHierarchyPanelEvent(const App::ProductHierarchyPanel::Event& event) {
    std::ostringstream stream = {};
    switch (event.kind) {
    case App::ProductHierarchyPanel::EventKind::SelectionChanged:
        stream << "SelectionChanged";
        break;
    case App::ProductHierarchyPanel::EventKind::Reparented:
        stream << "Reparented";
        break;
    case App::ProductHierarchyPanel::EventKind::MovedToRoot:
        stream << "MovedToRoot";
        break;
    case App::ProductHierarchyPanel::EventKind::RenameRequested:
        stream << "RenameRequested";
        break;
    case App::ProductHierarchyPanel::EventKind::None:
    default:
        stream << "None";
        break;
    }

    if (!event.itemId.empty()) {
        stream << " item=" << event.itemId;
    }
    if (!event.targetItemId.empty()) {
        stream << " target=" << event.targetItemId;
    }
    if (!event.label.empty()) {
        stream << " label=" << event.label;
    }
    return stream.str();
}

} // namespace

int Application::Run(HINSTANCE hInstance, int nCmdShow) {
    if (!Initialize(hInstance, nCmdShow)) {
        Shutdown();
        return 1;
    }

    MSG message = {};
    while (message.message != WM_QUIT) {
        if (PeekMessageW(&message, nullptr, 0U, 0U, PM_REMOVE)) {
            TranslateMessage(&message);
            DispatchMessageW(&message);
            continue;
        }

        RenderFrame();
    }

    Shutdown();
    return static_cast<int>(message.wParam);
}

bool Application::Initialize(HINSTANCE hInstance, int nCmdShow) {
    m_hInstance = hInstance;
    EnableDpiAwareness();
    const std::filesystem::path repoRoot = ResolveRepoRootPath();
    const std::filesystem::path logRoot =
        GetExecutableDirectory() / "logs";
    InitializeUIEditorRuntimeTrace(logRoot);
    SetUnhandledExceptionFilter(&Application::HandleUnhandledException);
    LogRuntimeTrace("app", "initialize begin");
    if (!m_editorContext.Initialize(repoRoot)) {
        LogRuntimeTrace(
            "app",
            "shell asset validation failed: " + m_editorContext.GetValidationMessage());
        return false;
    }

    WNDCLASSEXW windowClass = {};
    windowClass.cbSize = sizeof(windowClass);
    windowClass.style = CS_HREDRAW | CS_VREDRAW;
    windowClass.lpfnWndProc = &Application::WndProc;
    windowClass.hInstance = hInstance;
    windowClass.hCursor = LoadCursorW(nullptr, IDC_ARROW);
    windowClass.lpszClassName = kWindowClassName;
    m_windowClassAtom = RegisterClassExW(&windowClass);
    if (m_windowClassAtom == 0) {
        LogRuntimeTrace("app", "window class registration failed");
        return false;
    }

    m_hwnd = CreateWindowExW(
        0,
        kWindowClassName,
        kWindowTitle,
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT,
        CW_USEDEFAULT,
        1540,
        940,
        nullptr,
        nullptr,
        hInstance,
        this);
    if (m_hwnd == nullptr) {
        LogRuntimeTrace("app", "window creation failed");
        return false;
    }
    m_hostRuntime.Reset();
    m_hostRuntime.SetWindowDpi(QueryWindowDpi(m_hwnd));
    m_renderer.SetDpiScale(GetDpiScale());
    m_editorContext.SetExitRequestHandler([this]() {
        if (m_hwnd != nullptr) {
            PostMessageW(m_hwnd, WM_CLOSE, 0, 0);
        }
    });

    std::ostringstream dpiTrace = {};
    dpiTrace << "initial dpi=" << m_hostRuntime.GetWindowDpi() << " scale=" << GetDpiScale();
    LogRuntimeTrace("window", dpiTrace.str());

    if (!m_renderer.Initialize(m_hwnd)) {
        LogRuntimeTrace("app", "renderer initialization failed");
        return false;
    }
    RECT clientRect = {};
    GetClientRect(m_hwnd, &clientRect);
    const int clientWidth = (std::max)(clientRect.right - clientRect.left, 1L);
    const int clientHeight = (std::max)(clientRect.bottom - clientRect.top, 1L);
    if (!m_windowRenderer.Initialize(m_hwnd, clientWidth, clientHeight)) {
        LogRuntimeTrace("app", "d3d12 window renderer initialization failed");
        return false;
    }
    const Host::D3D12WindowRenderLoopAttachResult attachResult =
        m_windowRenderLoop.Attach(m_renderer, m_windowRenderer);
    if (!attachResult.interopWarning.empty()) {
        LogRuntimeTrace(
            "app",
            attachResult.interopWarning);
    }
    m_editorContext.AttachTextMeasurer(m_renderer);
    m_editorWorkspace.Initialize(repoRoot, m_renderer);
    m_editorWorkspace.AttachViewportWindowRenderer(m_windowRenderer);
    m_editorWorkspace.SetViewportSurfacePresentationEnabled(
        attachResult.hasViewportSurfacePresentation);
    if (!m_editorWorkspace.GetBuiltInIconError().empty()) {
        LogRuntimeTrace("icons", m_editorWorkspace.GetBuiltInIconError());
    }
    LogRuntimeTrace(
        "app",
        "workspace initialized: " +
            m_editorContext.DescribeWorkspaceState(m_editorWorkspace.GetShellInteractionState()));
    m_renderReady = true;

    ShowWindow(m_hwnd, nCmdShow);
    UpdateWindow(m_hwnd);

    m_autoScreenshot.Initialize(m_editorContext.GetShellAsset().captureRootPath);
    if (IsAutoCaptureOnStartupEnabled()) {
        m_autoScreenshot.RequestCapture("startup");
        m_editorContext.SetStatus("Capture", "Startup capture requested.");
    }
    LogRuntimeTrace("app", "initialize completed");
    return true;
}

void Application::Shutdown() {
    LogRuntimeTrace("app", "shutdown begin");
    m_renderReady = false;
    if (GetCapture() == m_hwnd) {
        ReleaseCapture();
    }

    m_autoScreenshot.Shutdown();
    m_editorWorkspace.Shutdown();
    m_windowRenderLoop.Detach();
    m_windowRenderer.Shutdown();
    m_renderer.Shutdown();

    if (m_hwnd != nullptr && IsWindow(m_hwnd)) {
        DestroyWindow(m_hwnd);
    }
    m_hwnd = nullptr;

    if (m_windowClassAtom != 0 && m_hInstance != nullptr) {
        UnregisterClassW(kWindowClassName, m_hInstance);
        m_windowClassAtom = 0;
    }

    LogRuntimeTrace("app", "shutdown end");
    ShutdownUIEditorRuntimeTrace();
}

void Application::RenderFrame() {
    if (!m_renderReady || m_hwnd == nullptr) {
        return;
    }

    RECT clientRect = {};
    GetClientRect(m_hwnd, &clientRect);
    const unsigned int pixelWidth =
        static_cast<unsigned int>((std::max)(clientRect.right - clientRect.left, 1L));
    const unsigned int pixelHeight =
        static_cast<unsigned int>((std::max)(clientRect.bottom - clientRect.top, 1L));
    const float width = PixelsToDips(static_cast<float>(pixelWidth));
    const float height = PixelsToDips(static_cast<float>(pixelHeight));

    UIDrawData drawData = {};
    UIDrawList& drawList = drawData.EmplaceDrawList("XCEditorShell");
    drawList.AddFilledRect(
        UIRect(0.0f, 0.0f, width, height),
        UIColor(0.10f, 0.10f, 0.10f, 1.0f));

    if (m_editorContext.IsValid()) {
        std::vector<UIInputEvent> frameEvents = std::move(m_pendingInputEvents);
        m_pendingInputEvents.clear();
        if (!frameEvents.empty() && IsVerboseRuntimeTraceEnabled()) {
            LogRuntimeTrace(
                "input",
                DescribeInputEvents(frameEvents) + " | " +
                    m_editorContext.DescribeWorkspaceState(
                        m_editorWorkspace.GetShellInteractionState()));
        }

        const Host::D3D12WindowRenderLoopFrameContext frameContext =
            m_windowRenderLoop.BeginFrame();
        if (!frameContext.warning.empty()) {
            LogRuntimeTrace("viewport", frameContext.warning);
        }

        m_editorWorkspace.Update(
            m_editorContext,
            UIRect(0.0f, 0.0f, width, height),
            frameEvents,
            BuildCaptureStatusText());
        const UIEditorShellInteractionFrame& shellFrame =
            m_editorWorkspace.GetShellFrame();
        if (IsVerboseRuntimeTraceEnabled() &&
            (!frameEvents.empty() ||
             shellFrame.result.workspaceResult.dockHostResult.layoutChanged ||
             shellFrame.result.workspaceResult.dockHostResult.commandExecuted)) {
            std::ostringstream frameTrace = {};
            frameTrace << "result consumed="
                       << (shellFrame.result.consumed ? "true" : "false")
                       << " layoutChanged="
                       << (shellFrame.result.workspaceResult.dockHostResult.layoutChanged ? "true" : "false")
                       << " commandExecuted="
                       << (shellFrame.result.workspaceResult.dockHostResult.commandExecuted ? "true" : "false")
                       << " active="
                       << m_editorContext.GetWorkspaceController().GetWorkspace().activePanelId
                       << " message="
                       << shellFrame.result.workspaceResult.dockHostResult.layoutResult.message;
            LogRuntimeTrace(
                "frame",
                frameTrace.str());
        }
        ApplyHostCaptureRequests(shellFrame.result);
        for (const App::ProductEditorWorkspaceTraceEntry& entry : m_editorWorkspace.GetTraceEntries()) {
            LogRuntimeTrace(entry.channel, entry.message);
        }
        ApplyHostedContentCaptureRequests();
        ApplyCurrentCursor();
        m_editorWorkspace.Append(drawList);
        if (frameContext.canRenderViewports) {
            m_editorWorkspace.RenderRequestedViewports(frameContext.renderContext);
        }
    } else {
        drawList.AddText(
            UIPoint(28.0f, 28.0f),
            "Editor shell asset invalid.",
            UIColor(0.92f, 0.92f, 0.92f, 1.0f),
            16.0f);
        drawList.AddText(
            UIPoint(28.0f, 54.0f),
            m_editorContext.GetValidationMessage().empty()
                ? std::string("Unknown validation error.")
                : m_editorContext.GetValidationMessage(),
            UIColor(0.72f, 0.72f, 0.72f, 1.0f),
            12.0f);
    }

    const Host::D3D12WindowRenderLoopPresentResult presentResult =
        m_windowRenderLoop.Present(drawData);
    if (!presentResult.warning.empty()) {
        LogRuntimeTrace("present", presentResult.warning);
    }
    m_autoScreenshot.CaptureIfRequested(
        m_renderer,
        drawData,
        pixelWidth,
        pixelHeight,
        presentResult.framePresented);
}

void Application::OnPaintMessage() {
    if (!m_renderReady || m_hwnd == nullptr) {
        return;
    }

    PAINTSTRUCT paintStruct = {};
    BeginPaint(m_hwnd, &paintStruct);
    RenderFrame();
    EndPaint(m_hwnd, &paintStruct);
}

float Application::GetDpiScale() const {
    return m_hostRuntime.GetDpiScale(kBaseDpiScale);
}

float Application::PixelsToDips(float pixels) const {
    const float dpiScale = GetDpiScale();
    return dpiScale > 0.0f ? pixels / dpiScale : pixels;
}

bool Application::IsPointerInsideClientArea() const {
    if (m_hwnd == nullptr || !IsWindow(m_hwnd)) {
        return false;
    }

    POINT screenPoint = {};
    if (!GetCursorPos(&screenPoint)) {
        return false;
    }

    const LPARAM pointParam = MAKELPARAM(
        static_cast<SHORT>(screenPoint.x),
        static_cast<SHORT>(screenPoint.y));
    return SendMessageW(m_hwnd, WM_NCHITTEST, 0, pointParam) == HTCLIENT;
}

LPCWSTR Application::ResolveCurrentCursorResource() const {
    switch (m_editorWorkspace.GetHostedContentCursorKind()) {
    case App::ProductProjectPanel::CursorKind::ResizeEW:
        return IDC_SIZEWE;
    case App::ProductProjectPanel::CursorKind::Arrow:
    default:
        break;
    }

    switch (m_editorWorkspace.GetDockCursorKind()) {
    case Widgets::UIEditorDockHostCursorKind::ResizeEW:
        return IDC_SIZEWE;
    case Widgets::UIEditorDockHostCursorKind::ResizeNS:
        return IDC_SIZENS;
    case Widgets::UIEditorDockHostCursorKind::Arrow:
    default:
        return IDC_ARROW;
    }
}

bool Application::ApplyCurrentCursor() const {
    if (!HasInteractiveCaptureState() && !IsPointerInsideClientArea()) {
        return false;
    }

    const HCURSOR cursor = LoadCursorW(nullptr, ResolveCurrentCursorResource());
    if (cursor == nullptr) {
        return false;
    }

    SetCursor(cursor);
    return true;
}

UIPoint Application::ConvertClientPixelsToDips(LONG x, LONG y) const {
    return UIPoint(
        PixelsToDips(static_cast<float>(x)),
        PixelsToDips(static_cast<float>(y)));
}

std::string Application::BuildCaptureStatusText() const {
    if (m_autoScreenshot.HasPendingCapture()) {
        return "Shot pending...";
    }

    if (!m_autoScreenshot.GetLastCaptureError().empty()) {
        return TruncateText(m_autoScreenshot.GetLastCaptureError(), 38u);
    }

    if (!m_autoScreenshot.GetLastCaptureSummary().empty()) {
        return TruncateText(m_autoScreenshot.GetLastCaptureSummary(), 38u);
    }

    return {};
}

void Application::LogRuntimeTrace(
    std::string_view channel,
    std::string_view message) const {
    AppendUIEditorRuntimeTrace(channel, message);
}

bool Application::IsVerboseRuntimeTraceEnabled() {
    static const bool s_enabled = ResolveVerboseRuntimeTraceEnabled();
    return s_enabled;
}

std::string Application::DescribeInputEvents(
    const std::vector<UIInputEvent>& events) const {
    std::ostringstream stream = {};
    stream << "events=[";
    for (std::size_t index = 0; index < events.size(); ++index) {
        if (index > 0u) {
            stream << " | ";
        }
        const UIInputEvent& event = events[index];
        stream << DescribeInputEventType(event)
               << '@'
               << static_cast<int>(event.position.x)
               << ','
               << static_cast<int>(event.position.y);
    }
    stream << ']';
    return stream.str();
}

void Application::OnResize(UINT width, UINT height) {
    ApplyWindowResize(width, height);
}

void Application::OnEnterSizeMove() {
    m_hostRuntime.BeginInteractiveResize();
}

void Application::OnExitSizeMove() {
    m_hostRuntime.EndInteractiveResize();
    UINT width = 0u;
    UINT height = 0u;
    if (QueryCurrentClientPixelSize(width, height)) {
        ApplyWindowResize(width, height);
    }
}

bool Application::ApplyWindowResize(UINT width, UINT height) {
    if (!m_renderReady || width == 0u || height == 0u) {
        return false;
    }

    const Host::D3D12WindowRenderLoopResizeResult resizeResult =
        m_windowRenderLoop.ApplyResize(width, height);
    m_editorWorkspace.SetViewportSurfacePresentationEnabled(
        resizeResult.hasViewportSurfacePresentation);

    if (!resizeResult.windowRendererWarning.empty()) {
        LogRuntimeTrace("present", resizeResult.windowRendererWarning);
    }

    if (!resizeResult.interopWarning.empty()) {
        LogRuntimeTrace("present", resizeResult.interopWarning);
    }

    return resizeResult.hasViewportSurfacePresentation;
}

bool Application::QueryCurrentClientPixelSize(UINT& outWidth, UINT& outHeight) const {
    outWidth = 0u;
    outHeight = 0u;
    if (m_hwnd == nullptr || !IsWindow(m_hwnd)) {
        return false;
    }

    RECT clientRect = {};
    if (!GetClientRect(m_hwnd, &clientRect)) {
        return false;
    }

    const LONG width = clientRect.right - clientRect.left;
    const LONG height = clientRect.bottom - clientRect.top;
    if (width <= 0 || height <= 0) {
        return false;
    }

    outWidth = static_cast<UINT>(width);
    outHeight = static_cast<UINT>(height);
    return true;
}

void Application::OnDpiChanged(UINT dpi, const RECT& suggestedRect) {
    m_hostRuntime.SetWindowDpi(dpi == 0u ? kDefaultDpi : dpi);
    m_renderer.SetDpiScale(GetDpiScale());
    if (m_hwnd != nullptr) {
        const LONG windowWidth = suggestedRect.right - suggestedRect.left;
        const LONG windowHeight = suggestedRect.bottom - suggestedRect.top;
        SetWindowPos(
            m_hwnd,
            nullptr,
            suggestedRect.left,
            suggestedRect.top,
            windowWidth,
            windowHeight,
            SWP_NOZORDER | SWP_NOACTIVATE);
        UINT clientWidth = 0u;
        UINT clientHeight = 0u;
        if (QueryCurrentClientPixelSize(clientWidth, clientHeight)) {
            ApplyWindowResize(clientWidth, clientHeight);
        }
    }

    std::ostringstream trace = {};
    trace << "dpi changed to " << m_hostRuntime.GetWindowDpi() << " scale=" << GetDpiScale();
    LogRuntimeTrace("window", trace.str());
}

void Application::ApplyHostCaptureRequests(const UIEditorShellInteractionResult& result) {
    if (result.requestPointerCapture && GetCapture() != m_hwnd) {
        SetCapture(m_hwnd);
    }
    if (result.releasePointerCapture && GetCapture() == m_hwnd) {
        ReleaseCapture();
    }
}

void Application::ApplyHostedContentCaptureRequests() {
    if (m_editorWorkspace.WantsHostPointerCapture() && GetCapture() != m_hwnd) {
        SetCapture(m_hwnd);
    }

    if (m_editorWorkspace.WantsHostPointerRelease() &&
        GetCapture() == m_hwnd &&
        !m_editorWorkspace.HasShellInteractiveCapture()) {
        ReleaseCapture();
    }
}

bool Application::HasInteractiveCaptureState() const {
    return m_editorWorkspace.HasInteractiveCapture();
}

void Application::QueuePointerEvent(
    UIInputEventType type,
    UIPointerButton button,
    WPARAM wParam,
    LPARAM lParam) {
    UIInputEvent event = {};
    event.type = type;
    event.pointerButton = button;
    event.position = ConvertClientPixelsToDips(
        GET_X_LPARAM(lParam),
        GET_Y_LPARAM(lParam));
    event.modifiers = m_inputModifierTracker.BuildPointerModifiers(static_cast<std::size_t>(wParam));
    m_pendingInputEvents.push_back(event);
}

void Application::QueuePointerLeaveEvent() {
    UIInputEvent event = {};
    event.type = UIInputEventType::PointerLeave;
    if (m_hwnd != nullptr) {
        POINT clientPoint = {};
        GetCursorPos(&clientPoint);
        ScreenToClient(m_hwnd, &clientPoint);
        event.position = ConvertClientPixelsToDips(clientPoint.x, clientPoint.y);
    }
    m_pendingInputEvents.push_back(event);
}

void Application::QueuePointerWheelEvent(short wheelDelta, WPARAM wParam, LPARAM lParam) {
    if (m_hwnd == nullptr) {
        return;
    }

    POINT screenPoint = {
        GET_X_LPARAM(lParam),
        GET_Y_LPARAM(lParam)
    };
    ScreenToClient(m_hwnd, &screenPoint);

    UIInputEvent event = {};
    event.type = UIInputEventType::PointerWheel;
    event.position = ConvertClientPixelsToDips(screenPoint.x, screenPoint.y);
    event.wheelDelta = static_cast<float>(wheelDelta);
    event.modifiers = m_inputModifierTracker.BuildPointerModifiers(static_cast<std::size_t>(wParam));
    m_pendingInputEvents.push_back(event);
}

void Application::QueueKeyEvent(UIInputEventType type, WPARAM wParam, LPARAM lParam) {
    UIInputEvent event = {};
    event.type = type;
    event.keyCode = MapVirtualKeyToUIKeyCode(wParam);
    event.modifiers = m_inputModifierTracker.ApplyKeyMessage(type, wParam, lParam);
    event.repeat = IsRepeatKeyMessage(lParam);
    m_pendingInputEvents.push_back(event);
}

void Application::QueueCharacterEvent(WPARAM wParam, LPARAM) {
    UIInputEvent event = {};
    event.type = UIInputEventType::Character;
    event.character = static_cast<std::uint32_t>(wParam);
    event.modifiers = m_inputModifierTracker.GetCurrentModifiers();
    m_pendingInputEvents.push_back(event);
}

void Application::QueueWindowFocusEvent(UIInputEventType type) {
    UIInputEvent event = {};
    event.type = type;
    m_pendingInputEvents.push_back(event);
}

std::filesystem::path Application::ResolveRepoRootPath() {
    std::string root = XCUIEDITOR_REPO_ROOT;
    if (root.size() >= 2u && root.front() == '"' && root.back() == '"') {
        root = root.substr(1u, root.size() - 2u);
    }
    return std::filesystem::path(root).lexically_normal();
}

LONG WINAPI Application::HandleUnhandledException(EXCEPTION_POINTERS* exceptionInfo) {
    if (exceptionInfo != nullptr &&
        exceptionInfo->ExceptionRecord != nullptr) {
        AppendUIEditorCrashTrace(
            exceptionInfo->ExceptionRecord->ExceptionCode,
            exceptionInfo->ExceptionRecord->ExceptionAddress);
    } else {
        AppendUIEditorCrashTrace(0u, nullptr);
    }

    return EXCEPTION_EXECUTE_HANDLER;
}

LRESULT CALLBACK Application::WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
    LRESULT dispatcherResult = 0;
    if (Host::WindowMessageDispatcher::TryHandleNonClientCreate(
            hwnd,
            message,
            lParam,
            dispatcherResult)) {
        return dispatcherResult;
    }

    Application* application = Host::WindowMessageDispatcher::GetApplicationFromWindow(hwnd);
    if (application != nullptr &&
        Host::WindowMessageDispatcher::TryDispatch(
            *application,
            message,
            wParam,
            lParam,
            dispatcherResult)) {
        return dispatcherResult;
    }

    switch (message) {
    case WM_MOUSEMOVE:
        if (application != nullptr) {
            if (!application->m_trackingMouseLeave) {
                TRACKMOUSEEVENT trackMouseEvent = {};
                trackMouseEvent.cbSize = sizeof(trackMouseEvent);
                trackMouseEvent.dwFlags = TME_LEAVE;
                trackMouseEvent.hwndTrack = hwnd;
                if (TrackMouseEvent(&trackMouseEvent)) {
                    application->m_trackingMouseLeave = true;
                }
            }
            application->QueuePointerEvent(
                UIInputEventType::PointerMove,
                UIPointerButton::None,
                wParam,
                lParam);
            return 0;
        }
        break;
    case WM_MOUSELEAVE:
        if (application != nullptr) {
            application->m_trackingMouseLeave = false;
            application->QueuePointerLeaveEvent();
            return 0;
        }
        break;
    case WM_LBUTTONDOWN:
        if (application != nullptr) {
            SetFocus(hwnd);
            application->QueuePointerEvent(
                UIInputEventType::PointerButtonDown,
                UIPointerButton::Left,
                wParam,
                lParam);
            return 0;
        }
        break;
    case WM_LBUTTONUP:
        if (application != nullptr) {
            application->QueuePointerEvent(
                UIInputEventType::PointerButtonUp,
                UIPointerButton::Left,
                wParam,
                lParam);
            return 0;
        }
        break;
    case WM_MOUSEWHEEL:
        if (application != nullptr) {
            application->QueuePointerWheelEvent(GET_WHEEL_DELTA_WPARAM(wParam), wParam, lParam);
            return 0;
        }
        break;
    case WM_SETFOCUS:
        if (application != nullptr) {
            application->m_inputModifierTracker.SyncFromSystemState();
            application->QueueWindowFocusEvent(UIInputEventType::FocusGained);
            return 0;
        }
        break;
    case WM_KILLFOCUS:
        if (application != nullptr) {
            application->m_inputModifierTracker.Reset();
            application->QueueWindowFocusEvent(UIInputEventType::FocusLost);
            return 0;
        }
        break;
    case WM_CAPTURECHANGED:
        if (application != nullptr &&
            reinterpret_cast<HWND>(lParam) != hwnd &&
            application->HasInteractiveCaptureState()) {
            application->QueueWindowFocusEvent(UIInputEventType::FocusLost);
            return 0;
        }
        break;
    case WM_KEYDOWN:
    case WM_SYSKEYDOWN:
        if (application != nullptr) {
            if (wParam == VK_F12) {
                application->m_autoScreenshot.RequestCapture("manual_f12");
            }
            application->QueueKeyEvent(UIInputEventType::KeyDown, wParam, lParam);
            return 0;
        }
        break;
    case WM_KEYUP:
    case WM_SYSKEYUP:
        if (application != nullptr) {
            application->QueueKeyEvent(UIInputEventType::KeyUp, wParam, lParam);
            return 0;
        }
        break;
    case WM_CHAR:
        if (application != nullptr) {
            application->QueueCharacterEvent(wParam, lParam);
            return 0;
        }
        break;
    case WM_ERASEBKGND:
        return 1;
    case WM_DESTROY:
        if (application != nullptr) {
            application->m_hwnd = nullptr;
        }
        PostQuitMessage(0);
        return 0;
    default:
        break;
    }

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

int RunXCUIEditorApp(HINSTANCE hInstance, int nCmdShow) {
    Application application;
    return application.Run(hInstance, nCmdShow);
}

} // namespace XCEngine::UI::Editor