#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "simfront.h"


/*
 * read and set force field parameters
 */

int setup_params(SimFront *sf)
{
  Param *param = &(sf->param);
  Pbuf *pbuf = &(sf->pbuf);
  MD_Sim *sim = sf->sim;
  MD_Int paramtype;
  int k;

  /* read in each param file in the order listed in config file */
  for (k = 0;  k < sf->paramfilelistnum;  k++) {
    if (param_open(param, sf->paramfilelist[k], PARAM_XPLOR)) {
      ERRMSG(sf, "call to param_open failed");
      return -1;
    }
    /*
     * Here is the strangeness in the MDIO Param interface:
     *
     *   Must have some amount of initial buffer space
     *   (this was set up in init()).  Return value from
     *   param_read() indicates by nonzero which buffer is
     *   full so that we need to resize in case any additional
     *   space is needed.
     *
     *   As params are read in, atom strings for each bond type
     *   are hashed with the array index for that bond.  This
     *   allows fast lookup for index when reading topology.
     *   Any params that are redefined are still placed in next
     *   additional pbuf array space, but the index value that
     *   the hashed string returns is silently overwritten to
     *   the new index (but no warning message is given).
     */
    while ((paramtype = param_read(param)) != 0) {
      void *vp;
      switch (paramtype) {
      case MD_ATOM_PARAM:
        vp = (void *) pbuf->atomp;
        vp = realloc(vp, (pbuf->atomp_len + INITLEN) * sizeof(MD_Atom_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->atomp = (MD_Atom_Param *) vp;
        pbuf->atomp_len += INITLEN;
        break;
  
      case MD_BOND_PARAM:
        vp = (void *) pbuf->bondp;
        vp = realloc(vp, (pbuf->bondp_len + INITLEN) * sizeof(MD_Bond_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->bondp = (MD_Bond_Param *) vp;
        pbuf->bondp_len += INITLEN;
        break;
  
      case MD_ANGLE_PARAM:
        vp = (void *) pbuf->anglep;
        vp = realloc(vp, (pbuf->anglep_len + INITLEN) * sizeof(MD_Angle_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->anglep = (MD_Angle_Param *) vp;
        pbuf->anglep_len += INITLEN;
        break;
  
      case MD_DIHED_PARAM:
        vp = (void *) pbuf->dihedp;
        vp = realloc(vp, (pbuf->dihedp_len + INITLEN) * sizeof(MD_Dihed_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->dihedp = (MD_Dihed_Param *) vp;
        pbuf->dihedp_len += INITLEN;
        break;
  
      case MD_IMPR_PARAM:
        vp = (void *) pbuf->imprp;
        vp = realloc(vp, (pbuf->imprp_len + INITLEN) * sizeof(MD_Impr_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->imprp = (MD_Impr_Param *) vp;
        pbuf->imprp_len += INITLEN;
        break;
  
      case MD_NBFIX_PARAM:
        vp = (void *) pbuf->nbfixp;
        vp = realloc(vp, (pbuf->nbfixp_len + INITLEN) * sizeof(MD_Nbfix_Param));
        if (vp == NULL) {
          ERRMSG(sf, strerror(errno));
          return -1;
        }
        pbuf->nbfixp = (MD_Nbfix_Param *) vp;
        pbuf->nbfixp_len += INITLEN;
        break;
  
      default:
        ERRMSG(sf, "unknown return value from param_read");
        return -1;
      }
    } /* end while loop read param file */
    if (param_close(param)) {
      ERRMSG(sf, "call to param_close failed");
      return -1;
    }
  } /* end for loop process all param files */


  /* set engine force field param data arrays */

  if (MD_setlen(sim, sf->id_atomparam, pbuf->atomp_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_atomparam, pbuf->atomp, pbuf->atomp_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  if (MD_setlen(sim, sf->id_bondparam, pbuf->bondp_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_bondparam, pbuf->bondp, pbuf->bondp_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  if (MD_setlen(sim, sf->id_angleparam, pbuf->anglep_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_angleparam, pbuf->anglep, pbuf->anglep_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  if (MD_setlen(sim, sf->id_dihedparam, pbuf->dihedp_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_dihedparam, pbuf->dihedp, pbuf->dihedp_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  if (MD_setlen(sim, sf->id_imprparam, pbuf->imprp_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_imprparam, pbuf->imprp, pbuf->imprp_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  if (MD_setlen(sim, sf->id_nbfixparam, pbuf->nbfixp_num) || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }
  if (MD_setdata(sim, sf->id_nbfixparam, pbuf->nbfixp, pbuf->nbfixp_num, 0)
      || MD_wait(sim)) {
    ERRMSG(sf, MD_errmsg(sim));
    return -1;
  }

  return 0;
}