#include "nmVTKOrientationMarkerController.h"

#include <QCoreApplication>
#include <QThread>

#include <vtkAxesActor.h>
#include <vtkCaptionActor2D.h>
#include <vtkMath.h>
#include <vtkOrientationMarkerWidget.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkTextProperty.h>

namespace {

// OrientationMarkerWidget 会维护观察关系和辅助 Renderer，只能在 GUI 线程操作。
bool isOrientationMarkerGuiThread()
{
    QCoreApplication* pApplication = QCoreApplication::instance();
    return pApplication == nullptr ||
            pApplication->thread() == QThread::currentThread();
}

// 方向轴杆和箭头使用各自的方向色，标签颜色由独立函数统一设置。
void setAxisColor(vtkProperty* pShaftProperty,
                   vtkProperty* pTipProperty,
                   double dRed,
                   double dGreen,
                   double dBlue)
{
    if(pShaftProperty != nullptr) {
        pShaftProperty->SetColor(dRed, dGreen, dBlue);
    }
    if(pTipProperty != nullptr) {
        pTipProperty->SetColor(dRed, dGreen, dBlue);
    }
}

void setCaptionColor(vtkCaptionActor2D* pCaptionActor,
                     double dRed,
                     double dGreen,
                     double dBlue)
{
    if(pCaptionActor != nullptr &&
       pCaptionActor->GetCaptionTextProperty() != nullptr) {
        pCaptionActor->GetCaptionTextProperty()->SetColor(
                    dRed, dGreen, dBlue);
    }
}

}

nmVTKOrientationMarkerController::nmVTKOrientationMarkerController()
    : m_pAxesActor(vtkSmartPointer<vtkAxesActor>::New()),
      m_pMarkerWidget(
          vtkSmartPointer<vtkOrientationMarkerWidget>::New()),
      m_pInteractor(nullptr),
      m_pRenderer(nullptr),
      m_bVisible(true),
      m_bViewAvailable(false)
{
    Q_ASSERT(isOrientationMarkerGuiThread());

    m_dViewport[0] = 0.015;
    m_dViewport[1] = 0.015;
    m_dViewport[2] = 0.13;
    m_dViewport[3] = 0.13;

    if(m_pAxesActor != nullptr) {
        m_pAxesActor->SetXAxisLabelText("X");
        m_pAxesActor->SetYAxisLabelText("Y");
        m_pAxesActor->SetZAxisLabelText("Z");
        setAxisColor(m_pAxesActor->GetXAxisShaftProperty(),
                     m_pAxesActor->GetXAxisTipProperty(),
                     1.0, 0.0, 0.0);
        setAxisColor(m_pAxesActor->GetYAxisShaftProperty(),
                     m_pAxesActor->GetYAxisTipProperty(),
                     0.0, 1.0, 0.0);
        setAxisColor(m_pAxesActor->GetZAxisShaftProperty(),
                     m_pAxesActor->GetZAxisTipProperty(),
                     0.0, 0.0, 1.0);
        setCaptionColor(m_pAxesActor->GetXAxisCaptionActor2D(),
                        1.0, 1.0, 1.0);
        setCaptionColor(m_pAxesActor->GetYAxisCaptionActor2D(),
                        1.0, 1.0, 1.0);
        setCaptionColor(m_pAxesActor->GetZAxisCaptionActor2D(),
                        1.0, 1.0, 1.0);
    }

    if(m_pMarkerWidget != nullptr) {
        // 构造阶段尚未绑定 Interactor，只关闭键盘入口并保存默认视口。
        m_pMarkerWidget->KeyPressActivationOff();
        m_pMarkerWidget->SetViewport(m_dViewport);
    }
}

nmVTKOrientationMarkerController::~nmVTKOrientationMarkerController()
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    unbindInteractor();
    m_pMarkerWidget = nullptr;
    m_pAxesActor = nullptr;
}

bool nmVTKOrientationMarkerController::bindInteractor(
        vtkRenderWindowInteractor* pInteractor,
        vtkRenderer* pRenderer)
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    if(!isOrientationMarkerGuiThread()) {
        return false;
    }

    // 每次绑定都从干净状态开始，避免 Widget 保留旧窗口的观察关系。
    unbindInteractor();

    vtkRenderWindow* pRenderWindow = pInteractor != nullptr ?
                pInteractor->GetRenderWindow() : nullptr;
    if(pInteractor == nullptr || pRenderer == nullptr ||
       pRenderWindow == nullptr || pRenderer->GetRenderWindow() != pRenderWindow ||
       m_pAxesActor == nullptr || m_pMarkerWidget == nullptr) {
        return false;
    }

    m_pInteractor = pInteractor;
    m_pRenderer = pRenderer;

    // 显式指定主 Renderer，不能依赖鼠标位置推断多 Renderer 窗口的父相机。
    m_pMarkerWidget->SetOrientationMarker(m_pAxesActor);
    m_pMarkerWidget->SetDefaultRenderer(m_pRenderer);
    m_pMarkerWidget->SetCurrentRenderer(m_pRenderer);
    m_pMarkerWidget->SetInteractor(m_pInteractor);
    updateEnabledState();

    bool bBindingValid =
            m_pMarkerWidget->GetInteractor() == m_pInteractor &&
            m_pMarkerWidget->GetDefaultRenderer() == m_pRenderer &&
            m_pMarkerWidget->GetOrientationMarker() ==
                m_pAxesActor.GetPointer();
    if(bBindingValid && m_bVisible && m_bViewAvailable) {
        bBindingValid = m_pMarkerWidget->GetEnabled() != 0 &&
                m_pMarkerWidget->GetInteractive() == 0 &&
                m_pMarkerWidget->GetCurrentRenderer() == m_pRenderer;
    }
    if(!bBindingValid) {
        unbindInteractor();
        return false;
    }
    return true;
}

void nmVTKOrientationMarkerController::unbindInteractor()
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    if(!isOrientationMarkerGuiThread()) {
        return;
    }

    if(m_pMarkerWidget == nullptr) {
        m_pInteractor = nullptr;
        m_pRenderer = nullptr;
        return;
    }

    // 只有已绑定且实际启用时才禁用，重复解绑不会触发 VTK 状态警告。
    if(m_pMarkerWidget->GetInteractor() != nullptr &&
       m_pMarkerWidget->GetEnabled() != 0) {
        m_pMarkerWidget->SetEnabled(0);
    }

    // 完整解绑会释放 Widget 持有的 Actor、Renderer 和 Interactor 引用。
    m_pMarkerWidget->SetOrientationMarker(nullptr);
    m_pMarkerWidget->SetDefaultRenderer(nullptr);
    m_pMarkerWidget->SetCurrentRenderer(nullptr);
    m_pMarkerWidget->SetInteractor(nullptr);
    m_pInteractor = nullptr;
    m_pRenderer = nullptr;
}

void nmVTKOrientationMarkerController::setVisible(bool bVisible)
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    if(!isOrientationMarkerGuiThread()) {
        return;
    }

    m_bVisible = bVisible;
    updateEnabledState();
}

bool nmVTKOrientationMarkerController::isVisible() const
{
    return m_bVisible;
}

void nmVTKOrientationMarkerController::setViewAvailable(bool bAvailable)
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    if(!isOrientationMarkerGuiThread()) {
        return;
    }

    m_bViewAvailable = bAvailable;
    updateEnabledState();
}

bool nmVTKOrientationMarkerController::isViewAvailable() const
{
    return m_bViewAvailable;
}

bool nmVTKOrientationMarkerController::setViewport(
        double dXMinimum,
        double dYMinimum,
        double dXMaximum,
        double dYMaximum)
{
    Q_ASSERT(isOrientationMarkerGuiThread());
    if(!isOrientationMarkerGuiThread() ||
       !vtkMath::IsFinite(dXMinimum) ||
       !vtkMath::IsFinite(dYMinimum) ||
       !vtkMath::IsFinite(dXMaximum) ||
       !vtkMath::IsFinite(dYMaximum) ||
       dXMinimum < 0.0 || dYMinimum < 0.0 ||
       dXMaximum > 1.0 || dYMaximum > 1.0 ||
       dXMaximum <= dXMinimum || dYMaximum <= dYMinimum ||
       m_pMarkerWidget == nullptr) {
        return false;
    }

    m_dViewport[0] = dXMinimum;
    m_dViewport[1] = dYMinimum;
    m_dViewport[2] = dXMaximum;
    m_dViewport[3] = dYMaximum;
    m_pMarkerWidget->SetViewport(m_dViewport);
    return true;
}

void nmVTKOrientationMarkerController::updateEnabledState()
{
    if(m_pMarkerWidget == nullptr) {
        return;
    }

    const bool bShouldEnable = m_pAxesActor != nullptr &&
            m_pInteractor != nullptr &&
            m_pRenderer != nullptr &&
            m_pMarkerWidget->GetInteractor() == m_pInteractor &&
            m_pMarkerWidget->GetDefaultRenderer() == m_pRenderer &&
            m_pMarkerWidget->GetOrientationMarker() ==
                m_pAxesActor.GetPointer() &&
            m_bVisible && m_bViewAvailable;
    if(bShouldEnable) {
        // VTK 7.1 禁用 Widget 后会清空 CurrentRenderer，恢复前必须重新指定。
        m_pMarkerWidget->SetCurrentRenderer(m_pRenderer);
        m_pMarkerWidget->SetEnabled(1);
        if(m_pMarkerWidget->GetEnabled() != 0 &&
           m_pMarkerWidget->GetInteractive() != 0) {
            // Interactive 只有在首次成功启用后设置才会被 VTK 正确接受。
            m_pMarkerWidget->SetInteractive(0);
        }
        return;
    }

    // 临时隐藏只禁用 Widget，保留 Marker、Interactor 和默认 Renderer 绑定。
    if(m_pMarkerWidget->GetInteractor() != nullptr &&
       m_pMarkerWidget->GetEnabled() != 0) {
        m_pMarkerWidget->SetEnabled(0);
    }
}