/* This file is part of Lemma, a geophysical modelling and inversion API.
 * More information is available at http://lemmasoftware.org
 */

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/**
 * @file
 * @date      08/07/2014 04:16:25 PM
 * @version   $Id$
 * @author    Trevor Irons (ti)
 * @email     Trevor.Irons@xri-geo.com
 * @copyright Copyright (c) 2014, XRI Geophysics, LLC
 * @copyright Copyright (c) 2014, Trevor Irons
 */

#include <vtkUnstructuredGrid.h>

#include <vtkUnstructuredGridReader.h>
#include <vtkUnstructuredGridWriter.h>

#include <vtkXMLUnstructuredGridReader.h>
#include <vtkXMLUnstructuredGridWriter.h>
#include <vtkDoubleArray.h>
#include <vtkPointData.h>

#include <cmath>


int main(int argc, char**argv) {

    std::cout << "Mesh processing routine\n";
    if (argc<3) {
        std::cout << "usage:\n" << "./utVTKEdge  inMesh.vtu outG.vtu" << std::endl;
    }

    vtkXMLUnstructuredGridReader* Reader = vtkXMLUnstructuredGridReader::New();
        std::cout << "Reading" << argv[1] << std::endl;
        Reader->SetFileName(argv[1]);
        Reader->Update();

        int nc = Reader->GetOutput()->GetNumberOfCells()  ;
        int nn = Reader->GetOutput()->GetNumberOfPoints()  ;

    std::cout << "Processing grid with nodes=" << nn << "\t cells=" << nc << "\n";

    // Input magnet size TODO get from file or .geo file even?
    double R = .25;          // radius of magnet
    double D0 = 10;          // Top of magnet
    double D1 = 11;          // Bottom of magnet
    double eps = 1e-2;       // epsilon for on the point
    // Pol = double[3];

    // Declare new array for the data
    vtkDoubleArray* G = vtkDoubleArray::New();
        G->SetNumberOfComponents(1);
        G->SetNumberOfTuples(nn);
        G->SetName("G");

    // Loop over nodes, look at position, set with G if on boundary
    double point[3];
    for (int in=0; in<nn; ++in) {
        Reader->GetOutput()->GetPoint(in, &point[0]);
        //std::cout << point[0] << "\t" <<point[1] << "\t" << point[2] << std::endl;
        double raddist = sqrt( point[0]*point[0] + point[1]*point[1] );
        if ( raddist > R - eps && raddist < R + eps && point[2] < D1 && point[2] > D0 ) {
            if ( point[1] < 0 ) {
                G->InsertTuple1( in,   1 );
            } else if (point[1] > 0) {
                G->InsertTuple1( in,  -1 );
            } else {
                G->InsertTuple1( in, 0 );
            }
        } else {
            G->InsertTuple1( in, 0 );
        }

    }

    // Add new data
    Reader->GetOutput()->GetPointData()->SetScalars( G );

    // Write out new file
    vtkXMLUnstructuredGridWriter* Writer = vtkXMLUnstructuredGridWriter::New();
        Writer->SetInputConnection(Reader->GetOutputPort());
        Writer->SetFileName( argv[2] );
        Writer->Write();

    Reader->Delete();


}