// $Id: Extract.cpp,v 1.17 2005-01-01 19:35:39 geuzaine Exp $
//
// Copyright (C) 1997-2005 C. Geuzaine, J.-F. Remacle
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
// 
// Please report all bugs and problems to <gmsh@geuz.org>.

#include "Plugin.h"
#include "Extract.h"
#include "List.h"
#include "Views.h"
#include "Context.h"
#include "Malloc.h"

#if defined(HAVE_MATH_EVAL)
#include "matheval.h"
#endif

extern Context_T CTX;

StringXNumber ExtractOptions_Number[] = {
  {GMSH_FULLRC, "iView", NULL, -1.}
};

StringXString ExtractOptions_String[] = {
  {GMSH_FULLRC, "Expression0", NULL, "v0"},
  {GMSH_FULLRC, "Expression1", NULL, ""},
  {GMSH_FULLRC, "Expression2", NULL, ""}
};

extern "C"
{
  GMSH_Plugin *GMSH_RegisterExtractPlugin()
  {
    return new GMSH_ExtractPlugin();
  }
}

GMSH_ExtractPlugin::GMSH_ExtractPlugin()
{
  ;
}

void GMSH_ExtractPlugin::getName(char *name) const
{
  strcpy(name, "Extract");
}

void GMSH_ExtractPlugin::getInfos(char *author, char *copyright, char *help_text) const
{
  strcpy(author, "C. Geuzaine (geuz@geuz.org)");
  strcpy(copyright, "DGR (www.multiphysics.com)");
  strcpy(help_text,
         "Plugin(Extract) extracts a combination of\n"
	 "components from the view `iView'. If\n"
	 "`Expression1' or `Expression2' is empty, the\n"
	 "plugin creates a scalar view using\n"
	 "`Expression0'; otherwise the plugin creates\n"
	 "a vector view. In addition to the usual\n"
	 "mathematical functions (Exp, Log, Sqrt, Sin,\n"
	 "Cos, Fabs, etc.) and operators (+, -, *, /, ^),\n"
	 "the expressions can contain the symbols v0,\n"
	 "v1, v2, ..., vn, which represent the n\n"
	 "components of the field, and the symbols x, y\n"
	 "and z, which represent the three spatial\n"
	 "coordinates. If `iView' < 0, the plugin is\n"
	 "run on the current view.\n"
	 "\n"
	 "Plugin(Extract) creates one new view.\n");
}

int GMSH_ExtractPlugin::getNbOptions() const
{
  return sizeof(ExtractOptions_Number) / sizeof(StringXNumber);
}

StringXNumber *GMSH_ExtractPlugin::getOption(int iopt)
{
  return &ExtractOptions_Number[iopt];
}

int GMSH_ExtractPlugin::getNbOptionsStr() const
{
  return sizeof(ExtractOptions_String) / sizeof(StringXString);
}

StringXString *GMSH_ExtractPlugin::getOptionStr(int iopt)
{
  return &ExtractOptions_String[iopt];
}

void GMSH_ExtractPlugin::catchErrorMessage(char *errorMessage) const
{
  strcpy(errorMessage, "Extract failed...");
}

static void extract(char *expr[3], List_T *inList, int inNb, 
		    List_T *outListScalar, int *outNbScalar, 
		    List_T *outListVector, int *outNbVector, 
		    int nbTime, int nbNod, int nbComp)
{
  if(!inNb)
    return;

  int outNbComp, *outNb;
  List_T *outList;
  
  if(!strlen(expr[1]) || !strlen(expr[2])){
    outNbComp = 1;
    outNb = outNbScalar;
    outList = outListScalar;
  }
  else{
    outNbComp = 3;
    outNb = outNbVector;
    outList = outListVector;
  }

  // if we have MathEval, we can evaluate arbitrary expressions;
  // otherwise, we only allow to extract single components

#if defined(HAVE_MATH_EVAL)
  void *f[3] = { NULL, NULL, NULL };
  for(int i = 0; i < outNbComp; i++){
    f[i] = evaluator_create(expr[i]);
    if(!f[i]){
      Msg(GERROR, "Invalid expression '%s'", expr[i]);
      for(int j = 0; j < i; j++)
	if(f[j]) evaluator_destroy(f[j]);
      return;
    }
  }
#else
  int comp[3] = { 0, 0, 0 };
  for(int i = 0; i < outNbComp; i++){
    if     (!strcmp(expr[i], "v0")) comp[i] = 0;
    else if(!strcmp(expr[i], "v1")) comp[i] = 1;
    else if(!strcmp(expr[i], "v2")) comp[i] = 2;
    else if(!strcmp(expr[i], "v3")) comp[i] = 3;
    else if(!strcmp(expr[i], "v4")) comp[i] = 4;
    else if(!strcmp(expr[i], "v5")) comp[i] = 5;
    else if(!strcmp(expr[i], "v6")) comp[i] = 6;
    else if(!strcmp(expr[i], "v7")) comp[i] = 7;
    else if(!strcmp(expr[i], "v8")) comp[i] = 8;
    else{
      Msg(GERROR, "Invalid expression '%s'", expr[i]);
      return;
    }
  }
#endif

  int nb = List_Nbr(inList) / inNb;
  for(int i = 0; i < List_Nbr(inList); i += nb) {
    double *x = (double *)List_Pointer_Fast(inList, i);
    double *y = (double *)List_Pointer_Fast(inList, i + nbNod);
    double *z = (double *)List_Pointer_Fast(inList, i + 2 * nbNod);
    for(int j = 0; j < 3 * nbNod; j++)
      List_Add(outList, List_Pointer_Fast(inList, i + j));
    for(int j = 0; j < nbTime; j++){
      for(int k = 0; k < nbNod; k++){
	double xx = x[k];
	double yy = y[k];
	double zz = z[k];
	double d[9] = {0., 0., 0., 0., 0., 0., 0., 0., 0.};
	for(int l = 0; l < nbComp; l++)
	  List_Read(inList, i + 3 * nbNod + nbNod * nbComp * j + nbComp * k + l, &d[l]);
	for(int l = 0; l < outNbComp; l++){
#if defined(HAVE_MATH_EVAL)
	  char *names[] = { "x", "y", "z", "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v8" };
	  double values[] = { xx, yy, zz, d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], d[8] };
	  double res = evaluator_evaluate(f[l], sizeof(names)/sizeof(names[0]), names, values);
#else
	  double res = d[comp[l]];
#endif
	  List_Add(outList, &res);
	}
      }
    }
    (*outNb)++;
  }

#if defined(HAVE_MATH_EVAL)
  for(int i = 0; i < outNbComp; i++)
    evaluator_destroy(f[i]);
#endif
}

Post_View *GMSH_ExtractPlugin::execute(Post_View * v)
{
  int iView = (int)ExtractOptions_Number[0].def;
  char *expr[3] = { ExtractOptions_String[0].def, 
		    ExtractOptions_String[1].def,
		    ExtractOptions_String[2].def };

  if(iView < 0)
    iView = v ? v->Index : 0;

  if(!List_Pointer_Test(CTX.post.list, iView)) {
    Msg(GERROR, "View[%d] does not exist", iView);
    return v;
  }

  Post_View *v1 = *(Post_View **)List_Pointer(CTX.post.list, iView);
  Post_View *v2 = BeginView(1);

  // points
  extract(expr, v1->SP, v1->NbSP, v2->SP, &v2->NbSP, v2->VP, &v2->NbVP, v1->NbTimeStep, 1, 1);
  extract(expr, v1->VP, v1->NbVP, v2->SP, &v2->NbSP, v2->VP, &v2->NbVP, v1->NbTimeStep, 1, 3);
  extract(expr, v1->TP, v1->NbTP, v2->SP, &v2->NbSP, v2->VP, &v2->NbVP, v1->NbTimeStep, 1, 9);
  // lines			                                  
  extract(expr, v1->SL, v1->NbSL, v2->SL, &v2->NbSL, v2->VL, &v2->NbVL, v1->NbTimeStep, 2, 1);
  extract(expr, v1->VL, v1->NbVL, v2->SL, &v2->NbSL, v2->VL, &v2->NbVL, v1->NbTimeStep, 2, 3);
  extract(expr, v1->TL, v1->NbTL, v2->SL, &v2->NbSL, v2->VL, &v2->NbVL, v1->NbTimeStep, 2, 9);
  // triangles			                                  
  extract(expr, v1->ST, v1->NbST, v2->ST, &v2->NbST, v2->VT, &v2->NbVT, v1->NbTimeStep, 3, 1);
  extract(expr, v1->VT, v1->NbVT, v2->ST, &v2->NbST, v2->VT, &v2->NbVT, v1->NbTimeStep, 3, 3);
  extract(expr, v1->TT, v1->NbTT, v2->ST, &v2->NbST, v2->VT, &v2->NbVT, v1->NbTimeStep, 3, 9);
  // quadrangles		                                  
  extract(expr, v1->SQ, v1->NbSQ, v2->SQ, &v2->NbSQ, v2->VQ, &v2->NbVQ, v1->NbTimeStep, 4, 1);
  extract(expr, v1->VQ, v1->NbVQ, v2->SQ, &v2->NbSQ, v2->VQ, &v2->NbVQ, v1->NbTimeStep, 4, 3);
  extract(expr, v1->TQ, v1->NbTQ, v2->SQ, &v2->NbSQ, v2->VQ, &v2->NbVQ, v1->NbTimeStep, 4, 9);
  // tets			                                  
  extract(expr, v1->SS, v1->NbSS, v2->SS, &v2->NbSS, v2->VS, &v2->NbVS, v1->NbTimeStep, 4, 1);
  extract(expr, v1->VS, v1->NbVS, v2->SS, &v2->NbSS, v2->VS, &v2->NbVS, v1->NbTimeStep, 4, 3);
  extract(expr, v1->TS, v1->NbTS, v2->SS, &v2->NbSS, v2->VS, &v2->NbVS, v1->NbTimeStep, 4, 9);
  // hexas			                                  
  extract(expr, v1->SH, v1->NbSH, v2->SH, &v2->NbSH, v2->VH, &v2->NbVH, v1->NbTimeStep, 8, 1);
  extract(expr, v1->VH, v1->NbVH, v2->SH, &v2->NbSH, v2->VH, &v2->NbVH, v1->NbTimeStep, 8, 3);
  extract(expr, v1->TH, v1->NbTH, v2->SH, &v2->NbSH, v2->VH, &v2->NbVH, v1->NbTimeStep, 8, 9);
  // prisms			                                  
  extract(expr, v1->SI, v1->NbSI, v2->SI, &v2->NbSI, v2->VI, &v2->NbVI, v1->NbTimeStep, 6, 1);
  extract(expr, v1->VI, v1->NbVI, v2->SI, &v2->NbSI, v2->VI, &v2->NbVI, v1->NbTimeStep, 6, 3);
  extract(expr, v1->TI, v1->NbTI, v2->SI, &v2->NbSI, v2->VI, &v2->NbVI, v1->NbTimeStep, 6, 9);
  // pyramids			                                  
  extract(expr, v1->SY, v1->NbSY, v2->SY, &v2->NbSY, v2->VY, &v2->NbVY, v1->NbTimeStep, 5, 1);
  extract(expr, v1->VY, v1->NbVY, v2->SY, &v2->NbSY, v2->VY, &v2->NbVY, v1->NbTimeStep, 5, 3);
  extract(expr, v1->TY, v1->NbTY, v2->SY, &v2->NbSY, v2->VY, &v2->NbVY, v1->NbTimeStep, 5, 9);

  // copy time data
  for(int i = 0; i < List_Nbr(v1->Time); i++)
    List_Add(v2->Time, List_Pointer(v1->Time, i));
  // finalize
  char name[1024], filename[1024];
  sprintf(name, "%s_Extract", v1->Name);
  sprintf(filename, "%s_Extract.pos", v1->Name);
  EndView(v2, 1, filename, name);
  return v2;
}