#include "nmPebiGridViewDataBuilder.h"

#include "nmPebiGridViewData.h"

#include "nmDataAnalyzeManager.h"
#include "nmDataNumericalAnalysisCase.h"

#include <QCoreApplication>
#include <QThread>

#include <vtkCellData.h>
#include <vtkDataArray.h>
#include <vtkMath.h>
#include <vtkUnstructuredGrid.h>

namespace {

QString builderText(const char* pText)
{
    return QCoreApplication::translate("nmPebiGridViewDataBuilder", pText);
}

bool isBuilderGuiThread()
{
    QCoreApplication* pApplication = QCoreApplication::instance();
    return pApplication == NULL ||
            pApplication->thread() == QThread::currentThread();
}

}

bool nmPebiGridViewDataBuilder::build(
        nmDataAnalyzeManager* pDataManager,
        nmPebiGridViewData* pViewData,
        QString* pError)
{
    Q_ASSERT(isBuilderGuiThread());
    if(pError != NULL) {
        pError->clear();
    }
    if(!isBuilderGuiThread()) {
        if(pError != NULL) {
            *pError = builderText(
                        "Grid preview data must be built in the GUI thread.");
        }
        return false;
    }
    if(pDataManager == NULL || pViewData == NULL) {
        if(pError != NULL) {
            *pError = builderText("The grid data source is unavailable.");
        }
        return false;
    }
    if(pDataManager->thread() != QThread::currentThread()) {
        if(pError != NULL) {
            *pError = builderText(
                        "Grid preview data must be built in the GUI thread.");
        }
        return false;
    }
    if(!pDataManager->isPebiGridValid()) {
        if(pError != NULL) {
            *pError = builderText("The PEBI grid has not been committed.");
        }
        return false;
    }
    if(pDataManager->getGridType() != NM_Grid_PEBI) {
        if(pError != NULL) {
            *pError = builderText("The committed grid is not a PEBI grid.");
        }
        return false;
    }

    vtkSmartPointer<vtkUnstructuredGrid> pGrid =
            pDataManager->getUnstructuredGrid();
    if(pGrid == NULL || pGrid->GetNumberOfPoints() <= 0 ||
       pGrid->GetNumberOfCells() <= 0) {
        if(pError != NULL) {
            *pError = builderText("The committed PEBI grid is empty.");
        }
        return false;
    }

    const nmDataNumericalAnalysisCase* pAnalysisCase =
            pDataManager->getNumericalAnalysisCase();
    if(pAnalysisCase == NULL) {
        if(pError != NULL) {
            *pError = builderText("The grid version is unavailable.");
        }
        return false;
    }

    // 先在局部对象中收集完整数据，任何校验错误都不会覆盖调用方旧数据。
    nmPebiGridViewData oCandidate;
    oCandidate.m_pGrid = pGrid;
    oCandidate.m_eGridType = NM_Grid_PEBI;
    oCandidate.m_nGridInputRevision =
            pAnalysisCase->getGridInputRevision();
    oCandidate.m_nValidCellCount = pGrid->GetNumberOfCells();

    // Material 只认可 CellData 中与 VTK 单元一一对应的数组。
    vtkCellData* pCellData = pGrid->GetCellData();
    vtkDataArray* pMaterialArray = pCellData != NULL
            ? pCellData->GetArray("Material") : NULL;
    oCandidate.m_bHasMaterial = pMaterialArray != NULL &&
            pMaterialArray->GetNumberOfTuples() == pGrid->GetNumberOfCells();

    *pViewData = oCandidate;
    return true;
}