/* read_description.c -- read parameters from description file

Copyright (C) 2012, 2013, 2014 INRIA

This file is part of GNU MPC.

GNU MPC 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.

GNU MPC 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 this program. If not, see http://www.gnu.org/licenses/ .
*/

#include <string.h>
#include "mpc-tests.h"

static size_t read_keyworddesc (mpc_datafile_context_t* datafile_context,
                                char **buffer_ptr, size_t buffer_length);

/* tuple to link name with the enum value */
typedef struct  {
  const char * name;  /* type name */
  mpc_param_t  val;   /* type enum */
} param_typeval_t;

/* available types for function description */
static const param_typeval_t sparam_typeval[]= {
  { "int"                 , NATIVE_INT  },
  { "unsigned long int"   , NATIVE_UL   },
  { "unsigned long"       , NATIVE_UL   },
  { "long int"            , NATIVE_L    },
  { "long"                , NATIVE_L    },
  { "double"              , NATIVE_D    },
  { "long double"         , NATIVE_LD   },
  { "double _Complex"     , NATIVE_DC   },
  { "long double _Complex", NATIVE_LDC  },
  { "intmax_t"            , NATIVE_IM   },
  { "uintmax_t"           , NATIVE_UIM  },
  { "mpz_ptr"             , GMP_Z       },
  { "mpz_srcptr"          , GMP_Z       },
  { "mpq_ptr"             , GMP_Q       },
  { "mpq_srcptr"          , GMP_Q       },
  { "mpf_ptr"             , GMP_F       },
  { "mpf_srcptr"          , GMP_F       },
  { "mpfr_inex"           , MPFR_INEX   },
  { "mpfr_ptr"            , MPFR        },
  { "mpfr_srcptr"         , MPFR        },
  { "mpfr_rnd_t"          , MPFR_RND    },
  { "mpc_inex"            , MPC_INEX    },
  { "mpc_ptr"             , MPC         },
  { "mpc_srcptr"          , MPC         },
  { "mpc_rnd_t"           , MPC_RND     },
  { "mpcc_inex"           , MPCC_INEX   }
};

/* read primitives */

static size_t
read_keyworddesc (mpc_datafile_context_t* datafile_context,
                  char **buffer_ptr,
                  size_t buffer_length)
{
  size_t pos;
  char *buffer;

  pos = 0;
  buffer = *buffer_ptr;

  while (datafile_context->nextchar != EOF
         && datafile_context->nextchar != '#'
         && datafile_context->nextchar != '\n')
    {
      if (pos + 1 > buffer_length)
        {
          if (buffer_length == 0)
            buffer_length = pos + 1;
          buffer = (char *) realloc (buffer, 2 * buffer_length);
          buffer_length *= 2;
          if (buffer == NULL)
            {
              printf ("Cannot allocate memory\n");
              exit (1);
            }
        }
      buffer[pos++] = (char) datafile_context->nextchar;
      datafile_context->nextchar = getc (datafile_context->fd);
    }
  while (pos>0 && isspace(buffer[pos-1])) pos--;

  if (pos + 1 > buffer_length)
    {
      buffer = (char *) realloc (buffer, buffer_length + 1);
      buffer_length++;
      if (buffer == NULL)
        {
          printf ("Cannot allocate memory\n");
          exit (1);
        }
    }
  buffer[pos] = '\0';

  *buffer_ptr = buffer;

  return buffer_length;
}

/* return the enum associated to name */
static mpc_param_t
description_findtype (const char *name)
{

  mpc_param_t r = sparam_typeval[0].val;
  size_t s = 0;
  const size_t send = sizeof (sparam_typeval) / sizeof (param_typeval_t);

  while (s < send && strcmp (sparam_typeval[s].name, name) != 0)
    s++;

  if (s < send)
    r = sparam_typeval[s].val;
  else
    {
      printf ("Error: Unable to find the type  '%s'\n",name);
      exit (1);
    }
  return r;
}

/* return the name  associated to the enum */
const char*
read_description_findname (mpc_param_t e)
{

  const char * name = NULL;
  size_t s = 0;
  const size_t send = sizeof (sparam_typeval) / sizeof (param_typeval_t);

  while (s < send && sparam_typeval[s].val != e)
    s++;

  if (s<send)
    name = sparam_typeval[s].name;
  else
    {
      printf ("Error: Unable to find the enum type\n");
      exit (1);
    }
  return name;
}


/* read the description file and fill param */
void
read_description (mpc_fun_param_t* param, const char *filename)
{
  mpc_datafile_context_t datafile_context;
  const char *pathname = filename;
  char *namestr = NULL;
  char *buffer = NULL;
  size_t len = 0;
  int nbout = 0;
  int nbin = 0;
  int rnd_mode = 0;
  int j;

  open_datafile (&datafile_context, filename);

  /* read NAME fields */
  tpl_skip_whitespace_comments(&datafile_context);
  len = read_keyworddesc (&datafile_context, &namestr, len);
  if (namestr == NULL || strcmp (namestr,"NAME:") != 0)
    {
      printf ("Error: Unable to read 'NAME:' in file '%s'\n",
              filename);
      exit (1);
    }

  tpl_skip_whitespace_comments (&datafile_context);
  read_keyworddesc (&datafile_context, &namestr, len);
  if (namestr == NULL)
    {
      printf ("Error: Unable to read the name of the function in file '%s'\n",
              filename);
      exit (1);
    }
  param->name = namestr;
  namestr = NULL;

  /* read RETURN fields */
  tpl_skip_whitespace_comments (&datafile_context);
  len = 0;
  len = read_keyworddesc (&datafile_context, &buffer, len);
  if (buffer == NULL || strcmp (buffer,"RETURN:") != 0)
    {
      printf ("Error: Unable to read 'RETURN:' in file '%s'\n",
              pathname);
      exit (1);
    }

  tpl_skip_whitespace_comments (&datafile_context);
  len = read_keyworddesc (&datafile_context, &buffer, len);
  if (buffer == NULL)
    {
      printf ("Error: Unable to read the return type of the function"
              " in file '%s'\n", pathname);
      exit (1);
    }
  param->T[nbout++] = description_findtype (buffer);

  /* read OUPUT fields */
  tpl_skip_whitespace_comments (&datafile_context);
  len = read_keyworddesc (&datafile_context, &buffer, len);
  if (buffer == NULL || strcmp (buffer,"OUTPUT:")!=0)
    {
      printf ("Error: Unable to read 'OUTPUT:' in file '%s'\n",
              pathname);
      exit (1);
    }

  while (!feof (datafile_context.fd))
    {
      tpl_skip_whitespace_comments (&datafile_context);
      len = read_keyworddesc (&datafile_context, &buffer, len);
      if (buffer == NULL)
        {
          printf ("Error: Unable to read the output type of the function"
                  " in file '%s'\n", pathname);
          exit (1);
        }
      if (strcmp (buffer, "INPUT:") == 0)
        break; /* exit the output loop */
      param->T[nbout++] = description_findtype (buffer);
    }

  /* read INPUT fields */
  while (!feof (datafile_context.fd))
    {
      tpl_skip_whitespace_comments (&datafile_context);
      len = read_keyworddesc (&datafile_context, &buffer, len);
      if (buffer == NULL)
        {
          printf ("Error: Unable to read the input type of the function"
                  " in file '%s'\n", pathname);
          exit (1);
        }
      if (strlen (buffer) == 0 && feof (datafile_context.fd))
        break;
      param->T[nbout+nbin] = description_findtype (buffer);
      if (param->T[nbout+nbin] == MPC_RND || param->T[nbout+nbin] == MPFR_RND)
        rnd_mode++;
      nbin++;
    }
  free (buffer);

  param->nbout = nbout;
  param->nbin  = nbin;
  param->nbrnd = rnd_mode;

  /* duplicate output parameters at the end for the expected values */
  for (j = 0; j < param->nbout; j++)
    {
      MPC_ASSERT (nbout + nbin + j < PARAMETER_ARRAY_SIZE);
      param->T[nbout + nbin + j] = param->T[j];
    }

  close_datafile(&datafile_context);
}