/* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   Copyright (c) 2015-2019 The plumed team
   (see the PEOPLE file at the root of the distribution for a list of names)

   See http://www.plumed.org for more information.

   This file is part of plumed, version 2.

   plumed is free software: you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   plumed is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with plumed.  If not, see <http://www.gnu.org/licenses/>.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
#include "AnalysisBase.h"
#include "ReadAnalysisFrames.h"
#include "reference/ReferenceConfiguration.h"
#include "reference/MetricRegister.h"
#include "core/PlumedMain.h"
#include "core/ActionSet.h"
#include "core/ActionRegister.h"
#include "core/ActionSetup.h"
#include "tools/IFile.h"

//+PLUMEDOC ANALYSIS READ_DISSIMILARITY_MATRIX
/*
Read a matrix of dissimilarities between a trajectory of atomic configurations from a file.

\par Examples

*/
//+ENDPLUMEDOC

namespace PLMD {
namespace analysis {

class ReadDissimilarityMatrix : public AnalysisBase {
private:
  unsigned nnodes;
  std::vector<DataCollectionObject> fake_data;
  std::string fname, wfile;
//  Matrix<double> dissimilarities;
  std::vector<std::vector<double> > dissimilarities;
  std::vector<double> weights;
public:
  static void registerKeywords( Keywords& keys );
  explicit ReadDissimilarityMatrix( const ActionOptions& ao );
  unsigned getNumberOfDataPoints() const ;
// Return the index of the data point in the base class
  unsigned getDataPointIndexInBase( const unsigned& idata ) const ;
/// This gives an error as if we read in the matrix we dont have the coordinates
  DataCollectionObject& getStoredData( const unsigned& idata, const bool& calcdist );
/// Tell everyone we have dissimilarities
  bool dissimilaritiesWereSet() const { return true; }
/// Get the dissimilarity between two data points
  double getDissimilarity( const unsigned&, const unsigned& );
/// Get the weight from the input file
  double getWeight( const unsigned& idata );
/// Just tell plumed to stop
  void update();
/// Read in the dissimilarity matrix
  void runFinalJobs();
/// This does nothing
  void performAnalysis() {};
/// Overwrite virtual function in base class
  void performTask( const unsigned&, const unsigned&, MultiValue& ) const { plumed_error(); }
};

PLUMED_REGISTER_ACTION(ReadDissimilarityMatrix,"READ_DISSIMILARITY_MATRIX")

void ReadDissimilarityMatrix::registerKeywords( Keywords& keys ) {
  AnalysisBase::registerKeywords( keys );
  keys.add("compulsory","FILE","an input file containing the matrix of dissimilarities");
  keys.add("optional","WFILE","input file containing weights of points");
  keys.reset_style("USE_OUTPUT_DATA_FROM","optional");
}

ReadDissimilarityMatrix::ReadDissimilarityMatrix( const ActionOptions& ao ):
  Action(ao),
  AnalysisBase(ao),
  nnodes(1)
{
  setStride(1); // Set the stride equal to one to ensure we don't get stuck in an infinite loop
  std::vector<ActionSetup*> setupActions=plumed.getActionSet().select<ActionSetup*>();
  if( my_input_data && (plumed.getActionSet().size()-setupActions.size())!=1 ) error("should only be this action and the READ_ANALYSIS_FRAMES command in the input file");
  if( !my_input_data && plumed.getActionSet().size()!=0 ) error("read dissimilarity matrix command must be at top of input file");

  parse("FILE",fname);
  log.printf("  reading dissimilarity matrix from file %s \n",fname.c_str() );
  parse("WFILE",wfile);

  if( wfile.length()>0 ) log.printf("  reading weights of nodes from file named %s \n",wfile.c_str() );
  else log.printf("  setting weights of all nodes equal to one\n");
}

void ReadDissimilarityMatrix::update() { if(!my_input_data) plumed.stop(); }

void ReadDissimilarityMatrix::runFinalJobs() {
  IFile mfile; mfile.open(fname);
  // Read in first line
  std::vector<std::string> words; nnodes=0;
  while( nnodes==0 ) {
    Tools::getParsedLine( mfile, words );
    nnodes=words.size();
  }

  std::vector<double> tmpdis( nnodes );
  for(unsigned j=0; j<nnodes; ++j) Tools::convert( words[j], tmpdis[j] );
  dissimilarities.push_back( tmpdis );

  while( Tools::getParsedLine( mfile, words ) ) {
    if( words.size()!=nnodes ) error("bad formatting in matrix file");
    for(unsigned j=0; j<nnodes; ++j) Tools::convert( words[j], tmpdis[j] );
    dissimilarities.push_back( tmpdis );
  }
  mfile.close();
  if( my_input_data && dissimilarities.size()!=getNumberOfDataPoints() ) {
    error("mismatch between number of data points in trajectory and the dimensions of the dissimilarity matrix");
  }
  if( !my_input_data ) fake_data.resize( dissimilarities.size() );

  weights.resize( dissimilarities.size() );
  if( wfile.length()>0 ) {
    IFile wfilef; wfilef.open(wfile);
    for(unsigned i=0; i<weights.size(); ++i) {
      Tools::getParsedLine( wfilef, words ); Tools::convert( words[0], weights[i] );
    }
    wfilef.close();
  } else {
    weights.assign(weights.size(),1.0);
  }
}

unsigned ReadDissimilarityMatrix::getNumberOfDataPoints() const {
  if( my_input_data ) return AnalysisBase::getNumberOfDataPoints();
  return dissimilarities.size();
}

unsigned ReadDissimilarityMatrix::getDataPointIndexInBase( const unsigned& idata ) const {
  return idata;
}

double ReadDissimilarityMatrix::getDissimilarity( const unsigned& iframe, const unsigned& jframe ) {
  return dissimilarities[iframe][jframe]*dissimilarities[iframe][jframe];
}

DataCollectionObject& ReadDissimilarityMatrix::getStoredData( const unsigned& idata, const bool& calcdist ) {
  plumed_massert( !calcdist, "cannot calc dist as this data was read in from input");
  if( my_input_data ) return AnalysisBase::getStoredData( idata, calcdist );
  return fake_data[idata];
}

double ReadDissimilarityMatrix::getWeight( const unsigned& idata ) {
  plumed_assert( idata<dissimilarities.size() ); return weights[idata];
}

}
}