#ifndef SIMFRONT_H
#define SIMFRONT_H

#include "mdapi.h"
#include "mdio.h"
#include "ihash.h"

#ifdef __cplusplus
extern "C" {
#endif


#define  TRUE  1

#define  PDBVEL      1000.0      /* conversion factor for vel to PDB */
#define  INV_PDBVEL     0.001    /* conversion factor for PDB to vel */
                  /* Xplor PDB stores velocity as A/ps, we need A/fs */

/* prototypes from linked engine */
MD_Errcode deven_create_engine(MD_Sim *);
void deven_destroy_engine(MD_Sim *);

typedef MD_Errcode (*FCreate)(MD_Sim *);
typedef void (*FDestroy)(MD_Sim *);

#define  TBUFLEN   10
#define  ARRAYLEN  10
#define  INITLEN   10

#define  STRING_SIZE     1024

#define  ERRMSG_SIZE     1024
#define  ERRMSG_MSG_PREC  928
#define  ERRMSG_FILE_PREC  64

#define  ARRLEN(x)  (sizeof(x) / sizeof(x[0]))

#define  ABORT(sf, msg)  terminate(sf, msg, __FILE__, __LINE__)

#define  ERRMSG(sf, msg)  errmsg(sf, msg, __FILE__, __LINE__)


struct SimFront_Tag;


typedef struct ConfigKeywd_Tag {
  const char *keywd;
  int (*set)(struct SimFront_Tag *, char *value);
} ConfigKeywd;


typedef struct CallbackInfo_Tag {
  char reductitle[STRING_SIZE];
  char reducfmt[STRING_SIZE];
  int numcols;
  int titlefreq;
} CallbackInfo;


typedef struct SimFront_Tag {
  /* error message buffer */
  char errmsg[ERRMSG_SIZE];

  /* command line parameters */
  const char *simfront;
  const char *configfile;
  const char *engine;
  FCreate create;
  FDestroy destroy;

  /* handle to simulation */
  MD_Sim *sim;

  /* SimFront config file keywords and hash table */
  const ConfigKeywd *cfkwd;
  int cfkwdnum;
  Ihash kwdtable;

  /* SimFront parameters set from config file */
  char **paramfilelist;
  int paramfilelistnum;
  int paramfilelistmax;
  char *topofile;
  char *coorfile;
  char *bincoorfile;
  char *velfile;
  char *binvelfile;
  char *cwd;
  char *outputfile;
  int isoutputbin;
  char *restartfile;
  int isrestartbin;
  int restartfreq;
  int energyfreq;
  int numsteps;
  double temperature;

  /*
   * Explanatory note:
   *
   * Structures Param, Pbuf, Topo, Tbuf, Pdb, and Binres all come from
   * the MDIO library.  This library interface is quite awkward and needs
   * to be redesigned to make it easier to use.
   */

  /* force field parameter file and buffer space */
  /* (in this case, space is dynamically allocated through Pbuf) */
  Param param;
  Pbuf pbuf;
  MD_Int id_atomparam, id_bondparam, id_angleparam, id_dihedparam,
         id_imprparam, id_nbfixparam;

  /* topology file and buffer space */
  /* (in this case, space is statically allocated and assigned to Tbuf) */
  Topo topo;
  Tbuf tbuf;
  MD_Atom atom[TBUFLEN];
  MD_Bond bond[TBUFLEN];
  MD_Angle angle[TBUFLEN];
  MD_Dihed dihed[TBUFLEN];
  MD_Impr impr[TBUFLEN];
  MD_Excl excl[TBUFLEN];
  MD_Int id_atom, id_bond, id_angle, id_dihed, id_impr, id_excl;

  /* trajectory file and buffer space */
  /* (in this case, buffer dvecbuf is provided directly to library calls) */
  Pdb pdb;
  Binres binres;
  MD_Dvec dvecbuf[ARRAYLEN];
  MD_Int id_pos, id_vel;

  /* callback info that doesn't change */
  CallbackInfo cbinfo;

} SimFront;


/* prototypes */

int init(SimFront *sf, int argc, char **argv);
void cleanup(SimFront *sf);
void terminate(SimFront *sf, const char *msg, const char *file, int line);
void errmsg(SimFront *sf, const char *msg, const char *file, int line);
void warning(SimFront *sf, const char *fmt, ...);
int setup_config(SimFront *sf);
int setup_params(SimFront *sf);
int setup_topology(SimFront *sf);
int setup_trajectory(SimFront *sf);
int setup_callbacks(SimFront *sf);
int run_simulation(SimFront *sf);


#ifdef __cplusplus
}
#endif

#endif /* SIMFRONT_H */