/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkEnSightGoldBinaryReader.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkEnSightGoldBinaryReader
 * @brief   class to read binary EnSight Gold files
 *
 * vtkEnSightGoldBinaryReader is a class to read EnSight Gold files into vtk.
 * Because the different parts of the EnSight data can be of various data
 * types, this reader produces multiple outputs, one per part in the input
 * file.
 * All variable information is being stored in field data.  The descriptions
 * listed in the case file are used as the array names in the field data.
 * For complex vector variables, the description is appended with _r (for the
 * array of real values) and _i (for the array if imaginary values).  Complex
 * scalar variables are stored as a single array with 2 components, real and
 * imaginary, listed in that order.
 * @warning
 * You must manually call Update on this reader and then connect the rest
 * of the pipeline because (due to the nature of the file format) it is
 * not possible to know ahead of time how many outputs you will have or
 * what types they will be.
 * This reader can only handle static EnSight datasets (both static geometry
 * and variables).
 * @par Thanks:
 * Thanks to Yvan Fournier for providing the code to support nfaced elements.
*/

#ifndef vtkEnSightGoldBinaryReader_h
#define vtkEnSightGoldBinaryReader_h

#include "vtkIOEnSightModule.h" // For export macro
#include "vtkEnSightReader.h"


class vtkMultiBlockDataSet;

class VTKIOENSIGHT_EXPORT vtkEnSightGoldBinaryReader : public vtkEnSightReader
{
public:
  static vtkEnSightGoldBinaryReader *New();
  vtkTypeMacro(vtkEnSightGoldBinaryReader, vtkEnSightReader);
  void PrintSelf(ostream& os, vtkIndent indent) override;

protected:
  vtkEnSightGoldBinaryReader();
  ~vtkEnSightGoldBinaryReader() override;

  // Returns 1 if successful.  Sets file size as a side action.
  int OpenFile(const char* filename);


  // Returns 1 if successful.  Handles constructing the filename, opening the file and checking
  // if it's binary
  int InitializeFile(const char* filename);

  /**
   * Read the geometry file.  If an error occurred, 0 is returned; otherwise 1.
   */
  int ReadGeometryFile(const char* fileName, int timeStep,
    vtkMultiBlockDataSet *output) override;

  /**
   * Read the measured geometry file.  If an error occurred, 0 is returned;
   * otherwise 1.
   */
  int ReadMeasuredGeometryFile(const char* fileName, int timeStep,
    vtkMultiBlockDataSet *output) override;

  /**
   * Read scalars per node for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.  If there will be more than one component in
   * the data array, it is assumed that 0 is the first component added.
   */
  int ReadScalarsPerNode(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output,
    int measured = 0,
    int numberOfComponents = 1,
    int component = 0) override;

  /**
   * Read vectors per node for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.
   */
  int ReadVectorsPerNode(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output,
    int measured = 0) override;

  /**
   * Read tensors per node for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.
   */
  int ReadTensorsPerNode(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output) override;

  /**
   * Read scalars per element for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.  If there will be more than one componenet in the
   * data array, it is assumed that 0 is the first component added.
   */
  int ReadScalarsPerElement(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output,
    int numberOfComponents = 1,
    int component = 0) override;

  /**
   * Read vectors per element for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.
   */
  int ReadVectorsPerElement(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output) override;

  /**
   * Read tensors per element for this dataset.  If an error occurred, 0 is
   * returned; otherwise 1.
   */
  int ReadTensorsPerElement(const char* fileName, const char* description,
    int timeStep, vtkMultiBlockDataSet *output) override;

  /**
   * Read an unstructured part (partId) from the geometry file and create a
   * vtkUnstructuredGrid output.  Return 0 if EOF reached. Return -1 if
   * an error occurred.
   */
  int CreateUnstructuredGridOutput(int partId,
    char line[80],
    const char* name,
    vtkMultiBlockDataSet *output) override;

  /**
   * Read a structured part from the geometry file and create a
   * vtkStructuredGrid output.  Return 0 if EOF reached.
   */
  int CreateStructuredGridOutput(int partId,
    char line[256],
    const char* name,
    vtkMultiBlockDataSet *output) override;

  /**
   * Read a structured part from the geometry file and create a
   * vtkRectilinearGrid output.  Return 0 if EOF reached.
   */
  int CreateRectilinearGridOutput(int partId, char line[256], const char* name,
    vtkMultiBlockDataSet *output);

  /**
   * Read a structured part from the geometry file and create a
   * vtkImageData output.  Return 0 if EOF reached.
   */
  int CreateImageDataOutput(int partId, char line[80], const char* name,
    vtkMultiBlockDataSet *output);

  /**
   * Internal function to read in a line up to 80 characters.
   * Returns zero if there was an error.
   */
  int ReadLine(char result[80]);

  //@{
  /**
   * Internal function to read in a single integer.
   * Returns zero if there was an error.
   */
  int ReadInt(int *result);
  int ReadPartId(int *result);
  //@}

  /**
   * Internal function to read in an integer array.
   * Returns zero if there was an error.
   */
  int ReadIntArray(int *result, int numInts);

  /**
   * Internal function to read in a single long.
   * Returns zero if there was an error.
   */
  int ReadLong(vtkTypeInt64 *result);

  /**
   * Internal function to read in a float array.
   * Returns zero if there was an error.
   */
  int ReadFloatArray(float *result, int numFloats);

  /**
   * Counts the number of timesteps in the geometry file
   * This function assumes the file is already open and returns the
   * number of timesteps remaining in the file
   * The file will be closed after calling this method
   */
  int CountTimeSteps();

  //@{
  /**
   * Read to the next time step in the geometry file.
   */
  int SkipTimeStep();
  int SkipStructuredGrid(char line[256]);
  int SkipUnstructuredGrid(char line[256]);
  int SkipRectilinearGrid(char line[256]);
  int SkipImageData(char line[256]);
  //@}

  /**
   * Seeks the IFile to the nearest time step that is <= the target time step
   */
  int SeekToCachedTimeStep(const char* fileName, int realTimeStep);

  /**
   * Add an entry the time step cache
   */
  void AddTimeStepToCache(const char* fileName, int realTimeStep, vtkTypeInt64 address);

  /**
   * Read the file index, if available, and add it to the time step cache
   */
  void AddFileIndexToCache(const char* fileName);

  int NodeIdsListed;
  int ElementIdsListed;
  int Fortran;

  ifstream *GoldIFile;
  // The size of the file could be used to choose byte order.
  vtkTypeUInt64 FileSize;

  class FileOffsetMapInternal;
  FileOffsetMapInternal *FileOffsets;

private:
  int SizeOfInt;
  vtkEnSightGoldBinaryReader(const vtkEnSightGoldBinaryReader&) = delete;
  void operator=(const vtkEnSightGoldBinaryReader&) = delete;
};

#endif
