#include <regex.h>
#include <cmath>
#include <cstring>
#include <cstdlib>
#include <cassert>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <string>
#include <fstream>
#include "loadRamses.hpp"
#include "load_data.hpp"
#include "fortran.hpp"
#include <map>

using namespace std;

CosmoTool::GadgetData *CosmoTool::loadRamses(const char *name)
{
  GadgetData *gd = (GadgetData *)malloc(sizeof(GadgetData));
  int id = 1;
  uint32_t totPart = 0;

  cout << "Detecting number of files and particles..." << endl;
  while (1)
    {
      ostringstream ss_fname;  
      ss_fname << name << setfill('0') << setw(5) << id;
      string fname = ss_fname.str();

      cout <<  " ... " << fname << endl;

      try
	{
	  UnformattedRead infile(fname);
	  
	  int nCpu, ndim, nPar;
	  
	  infile.beginCheckpoint();
	  nCpu = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  ndim = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  nPar = infile.readInt32();
	  infile.endCheckpoint();
	  
	  cout << "    NUMCPU=" << nCpu <<  " NUMDIM=" << ndim << " NumPart=" << nPar << endl;
	  
	  totPart += nPar;
	  id++;
	}
      catch (const NoSuchFileException& e)
	{
	  break;
	}
    }

  assert (totPart <= ((~(size_t)0)/sizeof(ParticleState)));
  size_t memSize = sizeof(ParticleState)*(size_t)totPart;
  cout << " Needing " << memSize / 1024 << " kBytes" << endl;
  gd->particles = (ParticleState *)malloc(memSize);
  assert(gd->particles != 0);
  gd->NumPart = totPart;
  gd->ntot_withmasses = totPart;
  gd->header.npart[0] = totPart;
  for (int k = 1; k < 6; k++)
    {
      gd->header.npart[k] = 0;
      gd->header.mass[k] = 0;
    }
  gd->header.num_files = id;
  gd->header.BoxSize = 200.0 * 1000; // kPc
  gd->header.Omega0 = 0.30; // ????
  gd->header.OmegaLambda = 0.70; // ????
  gd->header.HubbleParam = 0.70; // ????

  cout << " Total number part=" << totPart << endl
       << "Loading particles ..." << endl;

  uint32_t curPos = 0;
  id = 1;
  while (1)
    {
      ostringstream ss_fname;  
      ss_fname << name << setfill('0') << setw(5) << id;
      string fname = ss_fname.str();

      cout <<  " ... " << id;
      cout.flush();
      
      try {
	UnformattedRead infile(fname);
	
	int nCpu, ndim, nPar;
	
	
	infile.beginCheckpoint();
	nCpu = infile.readInt32();
	infile.endCheckpoint();
	
	infile.beginCheckpoint();
	ndim = infile.readInt32();
	infile.endCheckpoint();
	
	infile.beginCheckpoint();
	nPar = infile.readInt32();
	infile.endCheckpoint();
	
	ParticleState *s = &gd->particles[curPos];
	
	for (uint32_t i = nPar; i > 0; i--,s++)
	  s->Mass = 1.0;
	
	s = &gd->particles[curPos];
	infile.beginCheckpoint();
	for (uint32_t i = nPar; i > 0; i--)
	  {
	    s->Pos[0] = infile.readReal32();
	    s->Pos[0] *= gd->header.BoxSize;
	    s++;
	  }
	infile.endCheckpoint();

	s = &gd->particles[curPos];
	infile.beginCheckpoint();
	for (uint32_t i = nPar; i > 0; i--)
	{
	  s->Pos[1] = infile.readReal32();
	  s->Pos[1] *= gd->header.BoxSize;
	  s++;
	}
	infile.endCheckpoint();

	s = &gd->particles[curPos];
	infile.beginCheckpoint();
	for (uint32_t i = nPar; i > 0; i--)
	  {
	    s->Pos[2] = infile.readReal32();
	    s->Pos[2] *= gd->header.BoxSize;
	    s++;
	  }
	infile.endCheckpoint();

 	infile.beginCheckpoint();
	for (uint32_t i = 0; i < nPar; i++)
	  {
	    gd->particles[curPos+i].Vel[0] = infile.readReal32();
	  }
	infile.endCheckpoint();
	
	infile.beginCheckpoint();
	for (uint32_t i = 0; i < nPar; i++)
	  {
	    gd->particles[curPos+i].Vel[1] = infile.readReal32();
	  }
 	infile.endCheckpoint();

 	infile.beginCheckpoint();
	for (uint32_t i = 0; i < nPar; i++)
	  {
	    gd->particles[curPos+i].Vel[2] = infile.readReal32();
	  }
	infile.endCheckpoint();

	curPos += nPar;
      }
      catch (const NoSuchFileException& e)
	{
	  break;
	}

 
      id++;
    }

  cout << endl;

  return gd;
}

typedef struct 
{
  double unitLength;
  double aexp;
  double boxSize;
} InfoData;

int readInfoFile(const char *basename, int outputId, InfoData& info)
{
  ostringstream ss_fname;  
  ss_fname << basename << "/info_" << setfill('0') << setw(5) << outputId << ".txt";

  cout << "Opening info file " << ss_fname.str() << endl;
  ifstream infile(ss_fname.str().c_str());
  if (!infile)
    return 0;

  int err;
  regex_t unit_l_rx;

  //  const char *pattern = "^unit_l[ ]*=[ ]*([0-9\\.E+\\-]+)";
  const char *pattern = "^([A-Za-z_]+)[ ]*=[ ]*([0-9\\.E+\\-]+)";

  err = regcomp (&unit_l_rx, pattern, REG_EXTENDED);
  cout << unit_l_rx.re_nsub << endl;
  if (err)
    {
      char errString[255];
      regerror(err, &unit_l_rx, errString, sizeof(errString));
      cout << errString << endl;
      abort();
    }

  map<string,double> infoMap;
  string line;
  while (getline(infile, line))
    {
      regmatch_t allMatch[4];
      if (!regexec(&unit_l_rx, line.c_str(), 4, allMatch, 0))
	{
	  uint32_t start0 = allMatch[1].rm_so, end0 = allMatch[1].rm_eo;
	  uint32_t start1 = allMatch[2].rm_so, end1 = allMatch[2].rm_eo;

	  string keyword = line.substr(start0, end0-start0);
	  istringstream iss(line.substr(start1, end1-start1));
	  double unitLength;

	  iss >> unitLength;

	  infoMap[keyword] = unitLength;
	  
	}
    }
  
  regfree(&unit_l_rx);

  info.unitLength = infoMap["unit_l"];
  info.aexp = infoMap["aexp"];
  info.boxSize = infoMap["boxlen"];
  
  return 1;
}

CosmoTool::PurePositionData *CosmoTool::loadRamsesPosition(const char *basename, int outputId)
{
  PurePositionData *gd = (PurePositionData *)malloc(sizeof(PurePositionData));
  int id = 1;
  uint32_t totPart = 0;
  int nCpu = 0;
  InfoData info;
  
  static const double CM_IN_MPC = 3.08e24;

  if (!readInfoFile(basename, outputId, info))
    return 0;

  double L0 = info.boxSize*info.unitLength/CM_IN_MPC/info.aexp;
  cout << "L0=" << L0 << " Mpc" << endl;

  cout << "Detecting number of files and particles..." << endl;
  while (1)
    {
      ostringstream ss_fname;  
      ss_fname << basename << "/part_" << setfill('0') << setw(5) << outputId << ".out" << setfill('0') << setw(5) << id;
      string fname = ss_fname.str();

      cout <<  " ... " << fname << endl;
      

      try
	{
	  UnformattedRead infile(fname);
	  
	  int nCpu, ndim, nPar;
	  
	  infile.beginCheckpoint();
	  nCpu = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  ndim = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  nPar = infile.readInt32();
	  infile.endCheckpoint();
	  
	  cout << "    NUMCPU=" << nCpu <<  " NUMDIM=" << ndim << " NumPart=" << nPar << endl;
	  
	  totPart += nPar;
	  id++;
	}
      catch (const NoSuchFileException& e)
	{
	  break;
	}

    }

  assert (totPart <= ((~(size_t)0)/sizeof(FCoordinates)));
  size_t memSize = sizeof(FCoordinates)*(size_t)(totPart+totPart/nCpu);
  cout << " Needing " << memSize / 1024 << " kBytes" << endl;
  gd->pos = (FCoordinates *)malloc(sizeof(FCoordinates)*totPart);
  assert(gd->pos != 0);
  gd->NumPart = totPart;
  gd->BoxSize = L0*1000; 

  cout << " Total number part=" << totPart << endl
       << "Loading particles ..." << endl;

  uint32_t curPos = 0;
  id = 1;
  while (1)
    {
      ostringstream ss_fname;  
      ss_fname << basename << "/part_" << setfill('0') << setw(5) << outputId << ".out" << setfill('0') << setw(5) << id;
     
      string fname = ss_fname.str();
      int *idP;

      cout <<  " ... " << id;
      cout.flush();
      
      try
	{
	  UnformattedRead infile(fname);
	  
	  int nCpu, ndim, nPar;
	  
	  infile.beginCheckpoint();
	  nCpu = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  ndim = infile.readInt32();
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  nPar = infile.readInt32();
	  infile.endCheckpoint();
	  

	  FCoordinates *s = new FCoordinates[nPar];
	  
	  for (int k = 0; k < 3; k++)
	    {
	      infile.beginCheckpoint();
	      for (uint32_t i = 0; i < nPar; i++)
		{
		  s[i][k] = infile.readReal32();
		  s[i][k] *= gd->BoxSize;
		}
	      infile.endCheckpoint();
	    }

	  // SKIP VELOCITIES
	  for (int k = 0; k < 3; k++) {	
	    infile.beginCheckpoint();
	    for (uint32_t i = nPar; i > 0; i--)
	      {
		infile.readReal32();
	      }
	    infile.endCheckpoint();
	  }
	  
	  float minMass = INFINITY;
	  infile.beginCheckpoint();
	  for (uint32_t i = nPar; i > 0; i--)
	    {
	      float dummyF = infile.readReal32();
	      if (dummyF < minMass) minMass = dummyF;
	    }
	  infile.endCheckpoint();
	  
	  infile.beginCheckpoint();
	  for (uint32_t i = 0; i < nPar; i++)
	    {
	      int id = infile.readInt32();
	      id--;
	      assert(id >= 0);
	      assert(id < totPart);
	      memcpy(&gd->pos[id], &s[i], sizeof(FCoordinates));
	    }
	  infile.endCheckpoint();
      
	  delete[] s;
	  
	  curPos += nPar;
	} catch (const NoSuchFileException& e)
	{
	  break;
	}
      id++;
    }

  cout << endl;

  return gd;
}

#if 0
int main(int argc, char **argv)
{
  GadgetData *gd = loadRamses(argv[1]);
}

#endif

#if 0
int main(int argc, char **argv)
{
  GadgetData *gd = loadRamses(argv[1]);
}

#endif