#include "nmWxVTKRenderContainerWidget.h"

#include "nmVTKCameraController.h"
#include "nmVTKImageExporter.h"
#include "nmVTKInteractionManager.h"
#include "nmVTKOrientationMarkerController.h"
#include "nmVTKRotationCenterMarkerLayer.h"
#include "nmVTKRotationCenterPicker.h"
#include "nmVTKScene.h"
#include "nmVTKViewCommandController.h"

#include <QCoreApplication>
#include <QEvent>
#include <QFileDialog>
#include <QLabel>
#include <QMenu>
#include <QMessageBox>
#include <QMouseEvent>
#include <QStackedWidget>
#include <QThread>
#include <QTimer>
#include <QVBoxLayout>
#include <QVTKWidget.h>

#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL)
VTK_MODULE_INIT(vtkRenderingFreeType)
VTK_MODULE_INIT(vtkInteractionStyle)

#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>

namespace {

const char* const ROTATION_CENTER_MARKER_LAYER_ID =
        "nm.render.rotation_center_marker";

}

nmWxVTKRenderContainerWidget::nmWxVTKRenderContainerWidget(QWidget* pParent)
    : QWidget(pParent),
      m_pMainLayout(nullptr),
      m_pStateStack(nullptr),
      m_pStatePage(nullptr),
      m_pStateLabel(nullptr),
      m_pVtkWidget(nullptr),
      m_pRenderer(nullptr),
      m_pScene(nullptr),
      m_pSystemScene(nullptr),
      m_pCameraController(nullptr),
      m_pInteractionManager(nullptr),
      m_pImageExporter(nullptr),
      m_pViewCommandController(nullptr),
      m_pOrientationMarkerController(nullptr),
      m_pRotationCenterPicker(nullptr),
      m_pRotationCenterMarkerLayer(nullptr)
{
    Q_ASSERT(isGuiThread());

    // 1. 先创建稳定布局和状态页，避免无数据时改变容器尺寸。
    m_pMainLayout = new QVBoxLayout(this);
    m_pMainLayout->setContentsMargins(0, 0, 0, 0);
    m_pMainLayout->setSpacing(0);
    m_pStateStack = new QStackedWidget(this);
    m_pStatePage = new QWidget(m_pStateStack);
    m_pStateLabel = new QLabel(m_pStatePage);

    QVBoxLayout* pStateLayout = new QVBoxLayout(m_pStatePage);
    pStateLayout->setContentsMargins(24, 24, 24, 24);
    pStateLayout->addStretch();
    m_pStateLabel->setAlignment(Qt::AlignCenter);
    m_pStateLabel->setWordWrap(true);
    pStateLayout->addWidget(m_pStateLabel);
    pStateLayout->addStretch();

    // 2. QVTKWidget 由 Qt 父子关系拥有，并作为就绪状态页面。
    m_pVtkWidget = new QVTKWidget(m_pStateStack);
    m_pStateStack->addWidget(m_pVtkWidget);
    m_pStateStack->addWidget(m_pStatePage);
    m_pMainLayout->addWidget(m_pStateStack);

    // 3、4. RenderWindow 属于 QVTKWidget；Renderer 由本容器智能指针独占。
    vtkRenderWindow* pRenderWindow = getRenderWindow();
    vtkRenderWindowInteractor* pInteractor = getInteractor();
    m_pRenderer = vtkSmartPointer<vtkRenderer>::New();
    if(pRenderWindow != nullptr && m_pRenderer != nullptr) {
        pRenderWindow->AddRenderer(m_pRenderer);
        m_pRenderer->SetGradientBackground(true);
        m_pRenderer->SetBackground(0.67, 0.82, 0.94);
        m_pRenderer->SetBackground2(0.0, 0.5, 1.0);
    }

    // 5. 管理对象、图片服务和命令对象均只服务当前容器实例。
    // 业务图层和容器内部装饰分别管理；公开业务清场不会删除系统 Marker。
    m_pScene = new nmVTKScene(m_pRenderer);
    m_pSystemScene = new nmVTKScene(m_pRenderer);
    m_pCameraController = new nmVTKCameraController(m_pRenderer);
    m_pInteractionManager = new nmVTKInteractionManager(
                m_pCameraController);
    nmVTKRotationCenterMarkerLayer* pRotationCenterMarkerLayer =
            new nmVTKRotationCenterMarkerLayer(
                ROTATION_CENTER_MARKER_LAYER_ID);
    if(m_pSystemScene != nullptr &&
       m_pSystemScene->addLayer(pRotationCenterMarkerLayer)) {
        if(pRotationCenterMarkerLayer->bindRenderer(m_pRenderer)) {
            m_pRotationCenterMarkerLayer = pRotationCenterMarkerLayer;
        } else {
            m_pSystemScene->removeLayer(ROTATION_CENTER_MARKER_LAYER_ID);
        }
    } else {
        delete pRotationCenterMarkerLayer;
    }
    m_pRotationCenterPicker = new nmVTKRotationCenterPicker();
    m_pImageExporter = new nmVTKImageExporter();
    m_pImageExporter->setRenderWindow(pRenderWindow);
    m_pViewCommandController =
            new nmVTKViewCommandController(this, this);
    m_pViewCommandController->setCapabilities(
                nmVTKViewCommandController::ViewCommand_ZoomIn |
                nmVTKViewCommandController::ViewCommand_ZoomOut |
                nmVTKViewCommandController::ViewCommand_Fit |
                nmVTKViewCommandController::ViewCommand_Top |
                nmVTKViewCommandController::ViewCommand_Front |
                nmVTKViewCommandController::ViewCommand_Right |
                nmVTKViewCommandController::ViewCommand_Isometric |
                nmVTKViewCommandController::ViewCommand_ResetRotationCenter |
                nmVTKViewCommandController::ViewCommand_SaveImage |
                nmVTKViewCommandController::ViewCommand_CopyImage |
                nmVTKViewCommandController::ViewCommand_Print |
                nmVTKViewCommandController::ViewCommand_PrintPreview);
    // 命令控制器负责菜单顺序，容器继续向业务层转发同一个扩展时机。
    connect(m_pViewCommandController,
            SIGNAL(contextMenuAboutToShow(QMenu*)),
            this, SIGNAL(contextMenuAboutToShow(QMenu*)));
    connect(this, SIGNAL(rotationCenterPickingChanged(bool)),
            m_pViewCommandController,
            SLOT(setRotationCenterPicking(bool)));
    const bool bInteractionReady =
            m_pInteractionManager->bindInteractor(
                pInteractor, m_pRenderer);
    updateRotationCenterCommandAvailability();

    // 方向轴是独立辅助 Renderer；绑定失败只隐藏方向轴，不影响主视图初始化。
    m_pOrientationMarkerController =
            new nmVTKOrientationMarkerController();
    m_pOrientationMarkerController->bindInteractor(
                pInteractor, m_pRenderer);

    // 6. 只接管右键菜单，左键、中键和滚轮继续交给 VTK。
    m_pVtkWidget->installEventFilter(this);

    // 7. 基础 VTK 对象完整时进入就绪页，否则保留明确错误状态。
    if(pRenderWindow != nullptr && m_pRenderer != nullptr && bInteractionReady) {
        showReadyState();
    } else {
        showErrorState(tr("Unable to initialize the render view."));
    }
}

nmWxVTKRenderContainerWidget::~nmWxVTKRenderContainerWidget()
{
    Q_ASSERT(isGuiThread());

    // 1. 先阻止新的右键菜单回调进入销毁中的对象。
    if(m_pVtkWidget != nullptr) {
        m_pVtkWidget->removeEventFilter(this);
    }

    // 2. 先销毁 QAction，避免后续服务拆除期间再触发容器槽函数。
    if(m_pViewCommandController != nullptr) {
        delete m_pViewCommandController;
        m_pViewCommandController = nullptr;
    }

    // 3. 拾取器先恢复光标；场景标记必须在 Camera 和 Renderer 前解除观察关系。
    if(m_pRotationCenterPicker != nullptr) {
        m_pRotationCenterPicker->reset();
        delete m_pRotationCenterPicker;
        m_pRotationCenterPicker = nullptr;
    }
    nmVTKRotationCenterMarkerLayer* pRotationCenterMarkerLayer =
            getRotationCenterMarkerLayer();
    if(pRotationCenterMarkerLayer != nullptr) {
        pRotationCenterMarkerLayer->unbindRenderer();
    }

    // 4. MarkerWidget 持有 Interactor 和辅助 Renderer 引用，必须优先解绑。
    if(m_pOrientationMarkerController != nullptr) {
        m_pOrientationMarkerController->unbindInteractor();
        delete m_pOrientationMarkerController;
        m_pOrientationMarkerController = nullptr;
    }

    // 5. 图片服务不拥有 RenderWindow，先解除引用再销毁服务。
    if(m_pImageExporter != nullptr) {
        m_pImageExporter->setRenderWindow(nullptr);
        delete m_pImageExporter;
        m_pImageExporter = nullptr;
    }

    // 6. Interactor 必须先释放对默认 Style 的 VTK 引用。
    if(m_pInteractionManager != nullptr) {
        m_pInteractionManager->unbindInteractor();
        delete m_pInteractionManager;
        m_pInteractionManager = nullptr;
    }

    // 7. 两个 Scene 均在 Camera 和 Renderer 前清空；系统装饰先解除所有权。
    if(m_pSystemScene != nullptr) {
        m_pRotationCenterMarkerLayer = nullptr;
        m_pSystemScene->clear();
        delete m_pSystemScene;
        m_pSystemScene = nullptr;
    }
    if(m_pScene != nullptr) {
        m_pScene->clear();
        delete m_pScene;
        m_pScene = nullptr;
    }

    // 8. 相机控制器仅解除 Renderer 非所有权引用。
    if(m_pCameraController != nullptr) {
        m_pCameraController->setRenderer(nullptr);
        delete m_pCameraController;
        m_pCameraController = nullptr;
    }

    // 9. 最后从 RenderWindow 移除并释放当前实例 Renderer。
    vtkRenderWindow* pRenderWindow = getRenderWindow();
    if(pRenderWindow != nullptr && m_pRenderer != nullptr) {
        pRenderWindow->RemoveRenderer(m_pRenderer);
    }
    m_pRenderer = nullptr;
    // QVTKWidget、状态页和布局随后由 Qt 父子关系自动销毁。
}

QVTKWidget* nmWxVTKRenderContainerWidget::getVtkWidget() const
{
    return m_pVtkWidget;
}

vtkRenderer* nmWxVTKRenderContainerWidget::getRenderer() const
{
    return m_pRenderer;
}

vtkRenderWindow* nmWxVTKRenderContainerWidget::getRenderWindow() const
{
    return m_pVtkWidget != nullptr ? m_pVtkWidget->GetRenderWindow() : nullptr;
}

vtkRenderWindowInteractor*
nmWxVTKRenderContainerWidget::getInteractor() const
{
    vtkRenderWindow* pRenderWindow = getRenderWindow();
    return pRenderWindow != nullptr ? pRenderWindow->GetInteractor() : nullptr;
}

nmVTKScene* nmWxVTKRenderContainerWidget::getScene() const
{
    return m_pScene;
}

nmVTKViewCommandController*
nmWxVTKRenderContainerWidget::getViewCommandController() const
{
    return m_pViewCommandController;
}

nmVTKOrientationMarkerController*
nmWxVTKRenderContainerWidget::getOrientationMarkerController() const
{
    return m_pOrientationMarkerController;
}

void nmWxVTKRenderContainerWidget::setViewCommandCapabilities(
        nmVTKViewCommandController::ViewCommands eCommands)
{
    if(!eCommands.testFlag(
           nmVTKViewCommandController::ViewCommand_SetRotationCenter)) {
        // 能力移除前先结束模式，QAction 仅在随后同步隐藏和禁用。
        cancelRotationCenterPicking();
    }
    if(m_pViewCommandController != nullptr) {
        m_pViewCommandController->setCapabilities(eCommands);
    }
    updateRotationCenterMarkerVisibility();
}

void nmWxVTKRenderContainerWidget::setRotationCenterPickTarget(
        vtkProp* pTarget)
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread() || m_pRotationCenterPicker == nullptr) {
        return;
    }

    if(pTarget == nullptr ||
       m_pRotationCenterPicker->getPickTarget() != pTarget) {
        cancelRotationCenterPicking();
        m_pRotationCenterPicker->setPickTarget(pTarget);
    }
    if(pTarget == nullptr) {
        hideRotationCenterMarker();
    }
    updateRotationCenterCommandAvailability();
    updateRotationCenterMarkerVisibility();
}

bool nmWxVTKRenderContainerWidget::isRotationCenterPicking() const
{
    return m_pRotationCenterPicker != nullptr &&
            m_pRotationCenterPicker->isActive();
}

void nmWxVTKRenderContainerWidget::hideRotationCenterMarker()
{
    Q_ASSERT(isGuiThread());
    nmVTKRotationCenterMarkerLayer* pMarkerLayer =
            getRotationCenterMarkerLayer();
    if(isGuiThread() && pMarkerLayer != nullptr) {
        pMarkerLayer->setMarkerVisible(false);
    }
}

bool nmWxVTKRenderContainerWidget::installInteractionStyle(
        vtkInteractorStyle* pStyle)
{
    Q_ASSERT(isGuiThread());
    cancelRotationCenterPicking();
    const bool bSucceeded = isGuiThread() &&
            m_pInteractionManager != nullptr &&
            m_pInteractionManager->installInteractionStyle(pStyle);
    updateRotationCenterCommandAvailability();
    return bSucceeded;
}

bool nmWxVTKRenderContainerWidget::restoreDefaultInteraction()
{
    Q_ASSERT(isGuiThread());
    cancelRotationCenterPicking();
    const bool bSucceeded = isGuiThread() &&
            m_pInteractionManager != nullptr &&
            m_pInteractionManager->restoreDefaultInteraction();
    updateRotationCenterCommandAvailability();
    return bSucceeded;
}

void nmWxVTKRenderContainerWidget::clearInteractionStyle()
{
    Q_ASSERT(isGuiThread());
    cancelRotationCenterPicking();
    if(isGuiThread() && m_pInteractionManager != nullptr) {
        m_pInteractionManager->clearInteractionStyle();
    }
    updateRotationCenterCommandAvailability();
}

void nmWxVTKRenderContainerWidget::renderView()
{
    Q_ASSERT(isGuiThread());
    vtkRenderWindow* pRenderWindow = getRenderWindow();
    // Scene、Layer 和相机均不隐式渲染，批量更新最终汇聚到此入口。
    if(isGuiThread() && pRenderWindow != nullptr) {
        synchronizeRotationCenterMarker();
        pRenderWindow->Render();
    }
}

bool nmWxVTKRenderContainerWidget::fitTopViewWithoutRender()
{
    Q_ASSERT(isGuiThread());
    cancelRotationCenterPicking();
    // 相机控制器本身不触发 Render，便于业务图层完成整批更新后只渲染一次。
    return isGuiThread() && m_pCameraController != nullptr &&
            m_pCameraController->setTopView();
}

bool nmWxVTKRenderContainerWidget::resetRotationCenterWithoutRender()
{
    Q_ASSERT(isGuiThread());
    cancelRotationCenterPicking();
    if(!isGuiThread() || m_pCameraController == nullptr ||
       !m_pCameraController->resetRotationCenter()) {
        return false;
    }

    double dCenter[3];
    if(!m_pCameraController->getRotationCenter(dCenter)) {
        return false;
    }
    return applyRotationCenter(
                dCenter[0], dCenter[1], dCenter[2], true);
}

void nmWxVTKRenderContainerWidget::showReadyState()
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread()) {
        return;
    }
    // 状态页与 VTK 页尺寸稳定，切换页面不会重建 RenderWindow 或 Renderer。
    m_pStateStack->setCurrentWidget(m_pVtkWidget);
    if(m_pViewCommandController != nullptr) {
        m_pViewCommandController->setViewAvailable(true);
    }
    updateRotationCenterMarkerVisibility();
    if(m_pOrientationMarkerController != nullptr) {
        m_pOrientationMarkerController->setViewAvailable(true);
    }
    renderView();
}

void nmWxVTKRenderContainerWidget::showEmptyState(const QString& sMessage)
{
    showMessageState(ViewState_Empty, sMessage);
}

void nmWxVTKRenderContainerWidget::showErrorState(const QString& sMessage)
{
    showMessageState(ViewState_Error, sMessage);
}

void nmWxVTKRenderContainerWidget::showRenderingState(
        const QString& sMessage)
{
    showMessageState(ViewState_Rendering, sMessage);
}

void nmWxVTKRenderContainerWidget::zoomIn()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->zoomIn()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::zoomOut()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->zoomOut()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::fitView()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->fitView()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::resetCamera()
{
    cancelRotationCenterPicking();
    // 控制器用返回值表示相机是否确实改变，成功时只提交一次渲染。
    if(m_pCameraController != nullptr && m_pCameraController->resetCamera()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::setTopView()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->setTopView()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::setFrontView()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->setFrontView()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::setRightView()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr && m_pCameraController->setRightView()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::setIsometricView()
{
    cancelRotationCenterPicking();
    if(m_pCameraController != nullptr &&
       m_pCameraController->setIsometricView()) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::setRotationCenter(
        double dX,
        double dY,
        double dZ)
{
    cancelRotationCenterPicking();
    if(applyRotationCenter(dX, dY, dZ, true)) {
        renderView();
    }
}

void nmWxVTKRenderContainerWidget::resetRotationCenter()
{
    if(resetRotationCenterWithoutRender()) {
        renderView();
    }
}

bool nmWxVTKRenderContainerWidget::applyRotationCenter(
        double dX,
        double dY,
        double dZ,
        bool bShowMarker)
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread() || m_pCameraController == nullptr ||
       !m_pCameraController->setRotationCenter(dX, dY, dZ)) {
        return false;
    }

    // CameraController 是独立枢轴的唯一逻辑状态源；Marker 只保存显示副本。
    nmVTKRotationCenterMarkerLayer* pMarkerLayer =
            getRotationCenterMarkerLayer();
    if(pMarkerLayer != nullptr) {
        if(!pMarkerLayer->setWorldCenter(dX, dY, dZ)) {
            return false;
        }
        if(bShowMarker) {
            pMarkerLayer->setMarkerVisible(true);
        }
    }
    synchronizeRotationCenterMarker();
    return true;
}

void nmWxVTKRenderContainerWidget::cancelRotationCenterPicking()
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread()) {
        return;
    }

    if(m_pRotationCenterPicker != nullptr) {
        // reset 同时清除待消费 Release，并按进入模式前状态恢复光标。
        m_pRotationCenterPicker->reset();
    }
    emit rotationCenterPickingChanged(false);
}

bool nmWxVTKRenderContainerWidget::handleRotationCenterPickEvent(
        QEvent* pEvent)
{
    if(m_pRotationCenterPicker == nullptr || pEvent == nullptr) {
        return false;
    }

    const nmVTKRotationCenterPicker::PickEventResult oResult =
            m_pRotationCenterPicker->handleEvent(pEvent);
    if(oResult.eOutcome ==
       nmVTKRotationCenterPicker::PickOutcome_Hit) {
        double dPosition[3];
        if(m_pRotationCenterPicker->getPickedPosition(dPosition) &&
           applyRotationCenter(dPosition[0], dPosition[1],
                               dPosition[2], true)) {
            // 独立旋转中心和 Marker 已作为一批提交，只渲染一次。
            renderView();
        }
    }

    if(oResult.eOutcome !=
       nmVTKRotationCenterPicker::PickOutcome_None) {
        emit rotationCenterPickingChanged(false);
    }
    return oResult.bConsumed;
}

void nmWxVTKRenderContainerWidget::synchronizeRotationCenterMarker()
{
    nmVTKRotationCenterMarkerLayer* pMarkerLayer =
            getRotationCenterMarkerLayer();
    if(pMarkerLayer != nullptr && pMarkerLayer->isMarkerVisible()) {
        // synchronize 只更新世界几何，绝不从图层内部触发 Render。
        pMarkerLayer->synchronize();
    }
}

void nmWxVTKRenderContainerWidget::updateRotationCenterMarkerVisibility()
{
    nmVTKRotationCenterMarkerLayer* pMarkerLayer =
            getRotationCenterMarkerLayer();
    if(pMarkerLayer == nullptr) {
        return;
    }

    const bool bVisible = m_pViewCommandController != nullptr &&
            m_pViewCommandController->isViewAvailable() &&
            m_pViewCommandController->getCapabilities().testFlag(
                nmVTKViewCommandController::ViewCommand_SetRotationCenter) &&
            m_pRotationCenterPicker != nullptr &&
            m_pRotationCenterPicker->hasPickTarget() &&
            pMarkerLayer->hasWorldCenter();
    pMarkerLayer->setMarkerVisible(bVisible);
}

void nmWxVTKRenderContainerWidget::updateRotationCenterCommandAvailability()
{
    if(m_pViewCommandController == nullptr) {
        return;
    }

    const bool bAvailable = m_pRotationCenterPicker != nullptr &&
            m_pRotationCenterPicker->hasPickTarget() &&
            getRotationCenterMarkerLayer() != nullptr &&
            m_pInteractionManager != nullptr &&
            m_pInteractionManager->isDefaultInteractionActive();
    m_pViewCommandController->setRotationCenterPickingAvailable(
                bAvailable);
}

nmVTKRotationCenterMarkerLayer*
nmWxVTKRenderContainerWidget::getRotationCenterMarkerLayer() const
{
    if(m_pSystemScene == nullptr || m_pRotationCenterMarkerLayer == nullptr ||
       m_pSystemScene->getLayer(ROTATION_CENTER_MARKER_LAYER_ID) !=
           m_pRotationCenterMarkerLayer) {
        return nullptr;
    }
    return m_pRotationCenterMarkerLayer;
}

void nmWxVTKRenderContainerWidget::setRotationCenterPickingEnabled(
        bool bEnabled)
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread()) {
        return;
    }

    if(!bEnabled) {
        cancelRotationCenterPicking();
        return;
    }

    const bool bCommandAvailable = m_pViewCommandController != nullptr &&
            m_pViewCommandController->isViewAvailable() &&
            m_pViewCommandController->getCapabilities().testFlag(
                nmVTKViewCommandController::ViewCommand_SetRotationCenter);
    const bool bCanStart = bCommandAvailable &&
            m_pRotationCenterPicker != nullptr &&
            m_pRotationCenterPicker->getPickTarget() != nullptr &&
            getRotationCenterMarkerLayer() != nullptr &&
            m_pInteractionManager != nullptr &&
            m_pInteractionManager->isDefaultInteractionActive();
    if(!bCanStart ||
       !m_pRotationCenterPicker->start(m_pVtkWidget, m_pRenderer)) {
        if(m_pRotationCenterPicker != nullptr) {
            m_pRotationCenterPicker->reset();
        }
        updateRotationCenterCommandAvailability();
        emit rotationCenterPickingChanged(false);
        return;
    }

    emit rotationCenterPickingChanged(true);
}

bool nmWxVTKRenderContainerWidget::eventFilter(
        QObject* pObject,
        QEvent* pEvent)
{
    if(pObject != m_pVtkWidget || pEvent == nullptr) {
        return QWidget::eventFilter(pObject, pEvent);
    }

    // 一次性拾取优先于 VTK 相机交互和右键菜单，并继续吞掉对应 Release。
    if(m_pRotationCenterPicker != nullptr &&
       (m_pRotationCenterPicker->isActive() ||
        m_pRotationCenterPicker->hasPendingRelease()) &&
       handleRotationCenterPickEvent(pEvent)) {
        return true;
    }

    if(pEvent->type() == QEvent::FocusOut) {
        // 延后到本轮焦点切换结束，避免点击工具按钮启动模式时被旧 FocusOut 取消。
        QTimer::singleShot(
                    0, this,
                    SLOT(cancelRotationCenterPickingAfterFocusOut()));
    }

    if(pEvent->type() == QEvent::MouseButtonPress) {
        QMouseEvent* pMouseEvent = static_cast<QMouseEvent*>(pEvent);
        if(pMouseEvent->button() == Qt::RightButton) {
            // 菜单引用命令控制器长期持有的 QAction，不在每次右键时重复创建。
            QMenu oMenu(this);
            if(m_pViewCommandController != nullptr) {
                m_pViewCommandController->populateContextMenu(&oMenu);
            }
            if(!oMenu.isEmpty()) {
                oMenu.exec(pMouseEvent->globalPos());
            }
            // 返回 true 只消费右键按下，避免 VTK 同时启动一次交互动作。
            return true;
        }
        return false;
    }
    return QWidget::eventFilter(pObject, pEvent);
}

void nmWxVTKRenderContainerWidget::cancelRotationCenterPickingAfterFocusOut()
{
    if(m_pVtkWidget != nullptr && !m_pVtkWidget->hasFocus() &&
       m_pRotationCenterPicker != nullptr &&
       (m_pRotationCenterPicker->isActive() ||
        m_pRotationCenterPicker->hasPendingRelease())) {
        cancelRotationCenterPicking();
    }
}

void nmWxVTKRenderContainerWidget::saveImage()
{
    if(m_pImageExporter == nullptr) {
        return;
    }
    synchronizeRotationCenterMarker();
    // 实际编码格式由 QImage 按调用方选择的扩展名决定。
    const QString sFileName = QFileDialog::getSaveFileName(
                this,
                tr("Save Image"),
                QString(),
                tr("PNG Image (*.png);;JPEG Image (*.jpg);;BMP Image (*.bmp)"));
    if(!sFileName.isEmpty() && !m_pImageExporter->saveImage(sFileName)) {
        QMessageBox::warning(this,
                             tr("Save Failed"),
                             tr("Unable to save the image."));
    }
}

void nmWxVTKRenderContainerWidget::copyImage()
{
    synchronizeRotationCenterMarker();
    if(m_pImageExporter != nullptr &&
       !m_pImageExporter->copyImageToClipboard()) {
        QMessageBox::warning(this,
                             tr("Copy Failed"),
                             tr("Unable to capture the image."));
    }
}

void nmWxVTKRenderContainerWidget::printImage()
{
    if(m_pImageExporter != nullptr) {
        synchronizeRotationCenterMarker();
        m_pImageExporter->printImage(this);
    }
}

void nmWxVTKRenderContainerWidget::printPreview()
{
    if(m_pImageExporter != nullptr) {
        synchronizeRotationCenterMarker();
        m_pImageExporter->printPreview(this);
    }
}

void nmWxVTKRenderContainerWidget::showMessageState(
        ViewState eState,
        const QString& sMessage)
{
    Q_ASSERT(isGuiThread());
    if(!isGuiThread() || m_pStateStack == nullptr ||
       m_pStatePage == nullptr || m_pStateLabel == nullptr) {
        return;
    }

    // 所有非就绪状态共用同一页面，仅错误状态使用警示颜色。
    if(eState == ViewState_Error) {
        m_pStateLabel->setStyleSheet("QLabel { color: #a32626; }");
    } else {
        m_pStateLabel->setStyleSheet("QLabel { color: #4a4a4a; }");
    }
    m_pStateLabel->setText(sMessage);
    m_pStateStack->setCurrentWidget(m_pStatePage);
    // 非就绪状态先结束临时工具并清除手工标记，再禁用和取消 QAction。
    cancelRotationCenterPicking();
    hideRotationCenterMarker();
    if(m_pViewCommandController != nullptr) {
        m_pViewCommandController->setViewAvailable(false);
    }
    if(m_pOrientationMarkerController != nullptr) {
        m_pOrientationMarkerController->setViewAvailable(false);
    }
}

bool nmWxVTKRenderContainerWidget::isGuiThread() const
{
    QCoreApplication* pApplication = QCoreApplication::instance();
    return pApplication == nullptr ||
            pApplication->thread() == QThread::currentThread();
}