/*
 MDAL - Mesh Data Abstraction Library (MIT License)
 Copyright (C) 2019 Peter Petrik (zilolv at gmail dot com)
*/

#include "mdal_tuflowfv.hpp"
#include "mdal.h"
#include "mdal_utils.hpp"
#include "mdal_netcdf.hpp"
#include <math.h>
#include <assert.h>
#include <cstring>


size_t MDAL::TuflowFVActiveFlag::activeData(
  std::shared_ptr<NetCDFFile> ncFile,
  size_t timestep,
  size_t timestepsCount,
  size_t facesCount,
  int ncidActive,
  size_t indexStart,
  size_t count,
  int *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= facesCount ) )
    return 0;
  if ( timestep >= timestepsCount )
    return 0;
  if ( ncidActive < 0 )
    return 0;

  size_t copyValues = std::min( facesCount - indexStart, count );
  std::vector<int> values = ncFile->readIntArr(
                              ncidActive,
                              timestep,
                              indexStart,
                              1,
                              copyValues
                            );

  for ( size_t i = 0; i < copyValues; ++i )
  {
    // 0 means inactive in raw data file == false (0)
    // -1 means active in raw data file == true (1)
    int val = values[i] == 0 ? 0 : 1;
    buffer[i] = val;
  }
  return copyValues;
}

MDAL::TuflowFVDataset2D::TuflowFVDataset2D(
  DatasetGroup *parent,
  double fillValX,
  double fillValY,
  int ncidX,
  int ncidY,
  Classification classificationX,
  Classification classificationY,
  int ncidActive,
  CFDatasetGroupInfo::TimeLocation timeLocation,
  size_t timesteps,
  size_t values,
  size_t ts,
  std::shared_ptr<NetCDFFile> ncFile
)
  : CFDataset2D(
      parent,
      fillValX,
      fillValY,
      ncidX,
      ncidY,
      classificationX,
      classificationY,
      timeLocation,
      timesteps,
      values,
      ts,
      ncFile
    )
  , mNcidActive( ncidActive )
{
  setSupportsActiveFlag( true );
}

size_t MDAL::TuflowFVDataset2D::activeData( size_t indexStart, size_t count, int *buffer )
{
  return MDAL::TuflowFVActiveFlag::activeData(
           mNcFile,
           mTs,
           mTimesteps,
           group()->mesh()->facesCount(),
           mNcidActive,
           indexStart,
           count,
           buffer );
}

MDAL::TuflowFVDataset3D::TuflowFVDataset3D( MDAL::DatasetGroup *parent,
    int ncidX,
    int ncidY,
    int ncidActive, CFDatasetGroupInfo::TimeLocation timeLocation,
    size_t timesteps,
    size_t volumesCount,
    size_t facesCount,
    size_t levelFacesCount,
    size_t ts,
    size_t maximumLevelsCount,
    std::shared_ptr<NetCDFFile> ncFile )
  : MDAL::Dataset3D( parent, volumesCount, maximumLevelsCount )
  , mNcidX( ncidX )
  , mNcidY( ncidY )
  , mNcidActive( ncidActive )
  , mTimesteps( timesteps )
  , mFacesCount( facesCount )
  , mLevelFacesCount( levelFacesCount )
  , mTimeLocation( timeLocation )
  , mTs( ts )
  , mNcFile( ncFile )
{
  setSupportsActiveFlag( true );

  if ( ncFile )
  {
    mNcidVerticalLevels = ncFile->arrId( "NL" );
    mNcidVerticalLevelsZ = ncFile->arrId( "layerface_Z" );
    mNcidActive2D = ncFile->arrId( "stat" );
    mNcid3DTo2D = ncFile->arrId( "idx2" );
    mNcid2DTo3D = ncFile->arrId( "idx3" );
  }
}

MDAL::TuflowFVDataset3D::~TuflowFVDataset3D() = default;

size_t MDAL::TuflowFVDataset3D::verticalLevelCountData( size_t indexStart, size_t count, int *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= mFacesCount ) )
    return 0;
  if ( mNcidVerticalLevels < 0 )
    return 0;

  size_t copyValues = std::min( mFacesCount - indexStart, count );
  std::vector<int> vals = mNcFile->readIntArr(
                            mNcidVerticalLevels,
                            indexStart,
                            copyValues
                          );
  memcpy( buffer, vals.data(), copyValues * sizeof( int ) );
  return copyValues;
}

size_t MDAL::TuflowFVDataset3D::verticalLevelData( size_t indexStart, size_t count, double *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= mLevelFacesCount ) )
    return 0;
  if ( mTs >= mTimesteps )
    return 0;
  if ( mNcidVerticalLevelsZ < 0 )
    return 0;

  size_t copyValues = std::min( mLevelFacesCount - indexStart, count );
  std::vector<double> vals = mNcFile->readDoubleArr(
                               mNcidVerticalLevelsZ,
                               mTs,
                               indexStart,
                               1,
                               copyValues
                             );
  memcpy( buffer, vals.data(), copyValues * sizeof( double ) );
  return copyValues;
}

size_t MDAL::TuflowFVDataset3D::faceToVolumeData( size_t indexStart, size_t count, int *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= mFacesCount ) )
    return 0;
  if ( mNcid2DTo3D < 0 )
    return 0;

  size_t copyValues = std::min( mFacesCount - indexStart, count );
  std::vector<int> vals = mNcFile->readIntArr(
                            mNcid2DTo3D,
                            indexStart,
                            copyValues
                          );

  // indexed from 1 in FV, from 0 in MDAL
  for ( auto &element : vals )
    element -= 1;

  memcpy( buffer, vals.data(), copyValues * sizeof( int ) );
  return copyValues;
}

size_t MDAL::TuflowFVDataset3D::scalarVolumesData( size_t indexStart, size_t count, double *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= volumesCount() ) )
    return 0;
  if ( mTs >= mTimesteps )
    return 0;

  size_t copyValues = std::min( volumesCount() - indexStart, count );
  std::vector<double> vals;

  assert( mTimeLocation != CFDatasetGroupInfo::TimeDimensionLast );
  if ( mTimeLocation == CFDatasetGroupInfo::TimeDimensionFirst )
  {
    vals = mNcFile->readDoubleArr(
             mNcidX,
             mTs,
             indexStart,
             1,
             copyValues
           );
  }
  else     //NoTimeDimension
  {
    vals = mNcFile->readDoubleArr(
             mNcidX,
             indexStart,
             copyValues
           );
  }
  memcpy( buffer, vals.data(), copyValues * sizeof( double ) );
  return copyValues;
}

size_t MDAL::TuflowFVDataset3D::vectorVolumesData( size_t indexStart, size_t count, double *buffer )
{
  if ( ( count < 1 ) || ( indexStart >= volumesCount() ) )
    return 0;
  if ( mTs >= mTimesteps )
    return 0;

  size_t copyValues = std::min( volumesCount() - indexStart, count );
  std::vector<double> vals_x;
  std::vector<double> vals_y;

  assert( mTimeLocation != CFDatasetGroupInfo::TimeDimensionLast );
  if ( mTimeLocation == CFDatasetGroupInfo::TimeDimensionFirst )
  {
    vals_x = mNcFile->readDoubleArr(
               mNcidX,
               mTs,
               indexStart,
               1,
               copyValues
             );
    vals_y = mNcFile->readDoubleArr(
               mNcidY,
               mTs,
               indexStart,
               1,
               copyValues
             );

  }
  else
  {
    vals_x = mNcFile->readDoubleArr(
               mNcidX,
               indexStart,
               copyValues
             );
    vals_y = mNcFile->readDoubleArr(
               mNcidY,
               indexStart,
               copyValues
             );
  }


  for ( size_t i = 0; i < copyValues; ++i )
  {
    buffer[2 * i] = vals_x[i];
    buffer[2 * i + 1] = vals_y[i];
  }
  return copyValues;
}


size_t MDAL::TuflowFVDataset3D::activeData( size_t indexStart, size_t count, int *buffer )
{
  return MDAL::TuflowFVActiveFlag::activeData(
           mNcFile,
           mTs,
           mTimesteps,
           group()->mesh()->facesCount(),
           mNcidActive,
           indexStart,
           count,
           buffer );
}

// ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

MDAL::DriverTuflowFV::DriverTuflowFV():
  DriverCF( "TUFLOWFV",
            "TUFLOW FV",
            "*.nc",
            Capability::ReadMesh
          )
{
}

MDAL::DriverTuflowFV::~DriverTuflowFV() = default;

MDAL::DriverTuflowFV *MDAL::DriverTuflowFV::create()
{
  return new DriverTuflowFV();
}

MDAL::CFDimensions MDAL::DriverTuflowFV::populateDimensions( )
{
  CFDimensions dims;
  size_t count;
  int ncid;

  // 2D Mesh
  mNcFile->getDimension( "NumCells2D", &count, &ncid );
  dims.setDimension( CFDimensions::Face, count, ncid );

  mNcFile->getDimension( "MaxNumCellVert", &count, &ncid );
  dims.setDimension( CFDimensions::MaxVerticesInFace, count, ncid );

  mNcFile->getDimension( "NumVert2D", &count, &ncid );
  dims.setDimension( CFDimensions::Vertex, count, ncid );

  // 3D Mesh
  mNcFile->getDimension( "NumCells3D", &count, &ncid );
  dims.setDimension( CFDimensions::Volume3D, count, ncid );

  mNcFile->getDimension( "NumLayerFaces3D", &count, &ncid );
  dims.setDimension( CFDimensions::StackedFace3D, count, ncid );

  // Time
  mNcFile->getDimension( "Time", &count, &ncid );
  dims.setDimension( CFDimensions::Time, count, ncid );

  return dims;
}

void MDAL::DriverTuflowFV::populateElements( Vertices &vertices, Edges &, Faces &faces )
{
  populateVertices( vertices );
  populateFaces( faces );
}

void MDAL::DriverTuflowFV::populateVertices( MDAL::Vertices &vertices )
{
  assert( vertices.empty() );
  size_t vertexCount = mDimensions.size( CFDimensions::Vertex );
  vertices.resize( vertexCount );
  Vertex *vertexPtr = vertices.data();

  // Parse 2D Mesh
  const std::vector<double> vertices2D_x = mNcFile->readDoubleArr( "node_X", vertexCount );
  const std::vector<double> vertices2D_y = mNcFile->readDoubleArr( "node_Y", vertexCount );
  const std::vector<double> vertices2D_z = mNcFile->readDoubleArr( "node_Zb", vertexCount );

  for ( size_t i = 0; i < vertexCount; ++i, ++vertexPtr )
  {
    vertexPtr->x = vertices2D_x[i];
    vertexPtr->y = vertices2D_y[i];
    vertexPtr->z = vertices2D_z[i];
  }
}

void MDAL::DriverTuflowFV::populateFaces( MDAL::Faces &faces )
{
  assert( faces.empty() );
  size_t faceCount = mDimensions.size( CFDimensions::Face );
  size_t vertexCount = mDimensions.size( CFDimensions::Vertex );
  ( void )vertexCount;
  faces.resize( faceCount );

  // Parse 2D Mesh
  size_t verticesInFace = mDimensions.size( CFDimensions::MaxVerticesInFace );
  std::vector<int> face_nodes_conn = mNcFile->readIntArr( "cell_node", faceCount * verticesInFace );
  std::vector<int> face_vertex_counts = mNcFile->readIntArr( "cell_Nvert", faceCount );

  for ( size_t i = 0; i < faceCount; ++i )
  {
    size_t nVertices = static_cast<size_t>( face_vertex_counts[i] );
    std::vector<size_t> idxs;

    for ( size_t j = 0; j < nVertices; ++j )
    {
      size_t idx = verticesInFace * i + j;
      size_t val = static_cast<size_t>( face_nodes_conn[idx] - 1 ); //indexed from 1
      assert( val < vertexCount );
      idxs.push_back( val );
    }
    faces[i] = idxs;
  }
}

MDAL::DateTime MDAL::DriverTuflowFV::defaultReferenceTime() const
{
  return DateTime( 1990, 1, 1 );
}

void MDAL::DriverTuflowFV::calculateMaximumLevelCount()
{
  if ( mMaximumLevelsCount < 0 )
  {
    mMaximumLevelsCount = 0;
    int ncidVerticalLevels = mNcFile->arrId( "NL" );
    if ( ncidVerticalLevels < 0 )
      return;

    const size_t maxBufferLength = 1000;
    size_t indexStart = 0;
    size_t facesCount = mDimensions.size( CFDimensions::Face );
    while ( true )
    {
      size_t copyValues = std::min( facesCount - indexStart, maxBufferLength );
      if ( copyValues <= 0 ) break;
      std::vector<int> vals = mNcFile->readIntArr(
                                ncidVerticalLevels,
                                indexStart,
                                copyValues
                              );

      mMaximumLevelsCount = std::max( mMaximumLevelsCount, *std::max_element( vals.begin(), vals.end() ) );
      indexStart += copyValues;
    }
  }
}

void MDAL::DriverTuflowFV::addBedElevation( MDAL::MemoryMesh *mesh )
{
  MDAL::addBedElevationDatasetGroup( mesh, mesh->vertices );
}

std::string MDAL::DriverTuflowFV::getCoordinateSystemVariableName()
{
  const std::string projFile = MDAL::replace( mFileName, ".nc", ".prj" );
  return "file://" + projFile;
}

std::set<std::string> MDAL::DriverTuflowFV::ignoreNetCDFVariables()
{
  std::set<std::string> ignore_variables;

  ignore_variables.insert( getTimeVariableName() );
  ignore_variables.insert( "NL" );
  ignore_variables.insert( "cell_Nvert" );
  ignore_variables.insert( "cell_node" );
  ignore_variables.insert( "idx2" );
  ignore_variables.insert( "idx3" );
  ignore_variables.insert( "cell_X" );
  ignore_variables.insert( "cell_Y" );
  ignore_variables.insert( "cell_Zb" );
  ignore_variables.insert( "cell_A" );
  ignore_variables.insert( "node_X" );
  ignore_variables.insert( "node_Y" );
  ignore_variables.insert( "node_Zb" );
  ignore_variables.insert( "layerface_Z" );
  ignore_variables.insert( "stat" );

  return ignore_variables;
}

void MDAL::DriverTuflowFV::parseNetCDFVariableMetadata( int varid,
    std::string &variableName,
    std::string &name,
    bool *is_vector,
    bool *isPolar,
    bool *is_x )
{
  *is_vector = false;
  *is_x = true;
  *isPolar = false;

  std::string long_name = mNcFile->getAttrStr( "long_name", varid );
  if ( long_name.empty() || ( long_name == "??????" ) )
  {
    name = variableName;
  }
  else
  {
    if ( MDAL::startsWith( long_name, "maximum value of " ) )
      long_name = MDAL::replace( long_name, "maximum value of ", "" ) + "/Maximums";

    if ( MDAL::startsWith( long_name, "minimum value of " ) )
      long_name = MDAL::replace( long_name, "minimum value of ", "" ) + "/Minimums";

    if ( MDAL::startsWith( long_name, "time at maximum value of " ) )
      long_name = MDAL::replace( long_name, "time at maximum value of ", "" ) + "/Time at Maximums";

    if ( MDAL::startsWith( long_name, "time at minimum value of " ) )
      long_name = MDAL::replace( long_name, "time at minimum value of ", "" ) + "/Time at Minimums";

    variableName = long_name;

    if ( MDAL::startsWith( long_name, "x_" ) )
    {
      *is_vector = true;
      name = MDAL::replace( long_name, "x_", "" );
    }
    else if ( MDAL::startsWith( long_name, "y_" ) )
    {
      *is_vector = true;
      *is_x = false;
      name = MDAL::replace( long_name, "y_", "" );
    }
    else
    {
      name = long_name;
    }
  }
}

std::string MDAL::DriverTuflowFV::getTimeVariableName() const
{
  return "ResTime";
}

std::shared_ptr<MDAL::Dataset> MDAL::DriverTuflowFV::create2DDataset(
  std::shared_ptr<MDAL::DatasetGroup> group,
  size_t ts,
  const MDAL::CFDatasetGroupInfo &dsi,
  double fill_val_x, double fill_val_y )
{
  std::shared_ptr<MDAL::TuflowFVDataset2D> dataset = std::make_shared<MDAL::TuflowFVDataset2D>(
        group.get(),
        fill_val_x,
        fill_val_y,
        dsi.ncid_x,
        dsi.ncid_y,
        dsi.classification_x,
        dsi.classification_y,
        mNcFile->arrId( "stat" ),
        dsi.timeLocation,
        dsi.nTimesteps,
        dsi.nValues,
        ts,
        mNcFile
      );
  dataset->setStatistics( MDAL::calculateStatistics( dataset ) );
  return std::move( dataset );
}

std::shared_ptr<MDAL::Dataset> MDAL::DriverTuflowFV::create3DDataset( std::shared_ptr<MDAL::DatasetGroup> group, size_t ts,
    const MDAL::CFDatasetGroupInfo &dsi,
    double, double )
{
  calculateMaximumLevelCount();

  assert( dsi.timeLocation != CFDatasetGroupInfo::TimeDimensionLast );
  std::shared_ptr<MDAL::TuflowFVDataset3D> dataset = std::make_shared<MDAL::TuflowFVDataset3D>(
        group.get(),
        dsi.ncid_x,
        dsi.ncid_y,
        mNcFile->arrId( "stat" ),
        dsi.timeLocation,
        dsi.nTimesteps,
        mDimensions.size( CFDimensions::Type::Volume3D ),
        mDimensions.size( CFDimensions::Type::Face ),
        mDimensions.size( CFDimensions::Type::StackedFace3D ),
        ts,
        mMaximumLevelsCount,
        mNcFile
      );

  dataset->setStatistics( MDAL::calculateStatistics( dataset ) );
  return std::move( dataset );
}

std::vector<std::pair<double, double>> MDAL::DriverTuflowFV::parseClassification( int varid ) const
{
  MDAL_UNUSED( varid );
  return std::vector<std::pair<double, double>>();
}