/* Copyright (C) 2002-2003 Free Software Foundation, Inc.
   Contributed by Andy Vaught

This file is part of the GNU Fortran 95 runtime library (libgfortran).

Libgfortran 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, or (at your option)
any later version.

Libgfortran 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 Libgfortran; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "config.h"
#include <string.h>
#include <float.h>
#include "libgfortran.h"
#include "io.h"
#include <stdio.h>


#define star_fill(p, n) memset(p, '*', n)


typedef enum
{ SIGN_NONE, SIGN_MINUS, SIGN_PLUS }
sign_t;


void
write_a (fnode * f, const char *source, int len)
{
  int wlen;
  char *p;

  wlen = f->u.string.length < 0 ? len : f->u.string.length;

  p = write_block (wlen);
  if (p == NULL)
    return;

  if (wlen < len)
    memcpy (p, source, wlen);
  else
    {
      memcpy (p, source, len);
      memset (p + len, ' ', wlen - len);
    }
}

static int64_t
extract_int (const void *p, int len)
{
  int64_t i = 0;

  if (p == NULL)
    return i;

  switch (len)
    {
    case 1:
      i = *((const int8_t *) p);
      break;
    case 2:
      i = *((const int16_t *) p);
      break;
    case 4:
      i = *((const int32_t *) p);
      break;
    case 8:
      i = *((const int64_t *) p);
      break;
    default:
      internal_error ("bad integer kind");
    }

  return i;
}

static double
extract_real (const void *p, int len)
{
  double i = 0.0;
  switch (len)
    {
    case 4:
      i = *((const float *) p);
      break;
    case 8:
      i = *((const double *) p);
      break;
    default:
      internal_error ("bad real kind");
    }
  return i;

}


/* calculate sign()-- Given a flag that indicate if a value is
 * negative or not, return a sign_t that gives the sign that we need
 * to produce. */

static sign_t
calculate_sign (int negative_flag)
{
  sign_t s = SIGN_NONE;

  if (negative_flag)
    s = SIGN_MINUS;
  else
    switch (g.sign_status)
      {
      case SIGN_SP:
	s = SIGN_PLUS;
	break;
      case SIGN_SS:
	s = SIGN_NONE;
	break;
      case SIGN_S:
	s = options.optional_plus ? SIGN_PLUS : SIGN_NONE;
	break;
      }

  return s;
}


/* calculate_exp()-- returns the value of 10**d.  */

static double
calculate_exp (int d)
{
  int i;
  double r = 1.0;

  for (i = 0; i< (d >= 0 ? d : -d); i++)
    r *= 10;

  r = (d >= 0) ? r : 1.0 / r;

  return r;
}


/* calculate_G_format()-- geneate corresponding I/O format for
   FMT_G output.
   The rules to translate FMT_G to FMT_E or FNT_F from DEC fortran
   LRM (table 11-2, Chapter 11, "I/O Formatting", P11-25) is:

   Data Magnitude                              Equivalent Conversion
   0< m < 0.1-0.5*10**(-d-1)                   Ew.d[Ee]
   m = 0                                       F(w-n).(d-1), n' '
   0.1-0.5*10**(-d-1)<= m < 1-0.5*10**(-d)     F(w-n).d, n' '
   1-0.5*10**(-d)<= m < 10-0.5*10**(-d+1)      F(w-n).(d-1), n' '
   10-0.5*10**(-d+1)<= m < 100-0.5*10**(-d+2)  F(w-n).(d-2), n' '
   ................                           ..........
   10**(d-1)-0.5*10**(-1)<= m <10**d-0.5       F(w-n).0,n(' ')
   m >= 10**d-0.5                              Ew.d[Ee]

   notes: for Gw.d ,  n' ' means 4 blanks
          for Gw.dEe, n' ' means e+2 blanks  */

static fnode *
calculate_G_format (fnode *f, double value, int len, int *num_blank)
{
  int e = f->u.real.e;
  int d = f->u.real.d;
  int w = f->u.real.w;
  fnode *newf;
  double m, exp_d;
  int low, high, mid;
  int ubound, lbound;

  newf = get_mem (sizeof (fnode));

  /* Absolute value.  */
  m = (value > 0.0) ? value : -value;

  /* In case of the two data magnitude ranges,
     generate E editing, Ew.d[Ee].  */
  exp_d = calculate_exp (d);
  if ((m > 0.0 && m < 0.1 - 0.05 / (double) exp_d)
      || (m >= (double) exp_d - 0.5 ))
    {
      newf->format = FMT_E;
      newf->u.real.w = w;
      newf->u.real.d = d;
      newf->u.real.e = e;
      *num_blank = e + 2;
      return newf;
    }

  /* Use binary search to find the data magnitude range.  */
  mid = 0;
  low = 0;
  high = d + 1;
  lbound = 0;
  ubound = d + 1;

  while (low <= high)
    {
      double temp;
      mid = (low + high) / 2;

      /* 0.1 * 10**mid - 0.5 * 10**(mid-d-1)  */
      temp = 0.1 * calculate_exp (mid) - 0.5 * calculate_exp (mid - d - 1);

      if (m < temp)
        {
          ubound = mid;
          if (ubound == lbound + 1)
            break;
          high = mid - 1;
        }
      else if (m > temp)
        {
          lbound = mid;
          if (ubound == lbound + 1)
            {
              mid ++;
              break;
            }
          low = mid + 1;
        }
      else
        break;
    }

  /* Generate the F editing. F(w-4).(-(mid-d-1)), 4' '.  */
  newf->format = FMT_F;
  newf->u.real.w = f->u.real.w - 4;

  /* Special case.  */
  if (m == 0.0)
    newf->u.real.d = d - 1;
  else
    newf->u.real.d = - (mid - d - 1);

  *num_blank = 4;

  /* For F editing, the scale factor is ignored.  */
  g.scale_factor = 0;
  return newf;
}


/* output_float() -- output a real number according to its format
                     which is FMT_G free */

static void
output_float (fnode *f, double value, int len)
{
  int w, d, e, e_new;
  int digits;
  int nsign, nblank, nesign;
  int sca, neval, itmp;
  char *p;
  const char *q, *intstr, *base;
  double n;
  format_token ft;
  char exp_char = 'E';
  int with_exp = 1;
  int scale_flag = 1 ;
  double minv = 0.0, maxv = 0.0;
  sign_t sign = SIGN_NONE, esign = SIGN_NONE;

  int intval = 0, intlen = 0;
  int j;
  
  /* EXP value for this number */
  neval = 0;

  /* Width of EXP and it's sign*/
  nesign = 0;

  ft = f->format;
  w = f->u.real.w;
  d = f->u.real.d + 1;

  /* Width of the EXP */
  e = 0;

  sca = g.scale_factor;
  n = value;

  sign = calculate_sign (n < 0.0);
  if (n < 0)
    n = -n;

  /* Width of the sign for the whole number */
  nsign = (sign == SIGN_NONE ? 0 : 1);

  digits = 0;
  if (ft != FMT_F)
    {
      e = f->u.real.e;
    }
  if (ft == FMT_F || ft == FMT_E || ft == FMT_D)
    {
      if (ft == FMT_F)
        scale_flag = 0;
      if (ft == FMT_D)
        exp_char = 'D' ;
      minv = 0.1;
      maxv = 1.0;

      /* Here calculate the new val of the number with consideration
         of Globle Scale value */
      while (sca >  0)
        {
          minv *= 10.0;
          maxv *= 10.0;
          n *= 10.0;
          sca -- ;
          neval --;
        }

      /* Now calculate the new Exp value for this number */
      sca = g.scale_factor;
      while(sca >= 1)
        {
          sca /= 10;
          digits ++ ;
        }
    }

   if (ft == FMT_EN )
     {
       minv = 1.0;
       maxv = 1000.0;
     }
   if (ft == FMT_ES)
     {
       minv = 1.0;
       maxv = 10.0;
     }

   /* OK, let's scale the number to appropriate range */
   while (scale_flag && n > 0.0 && n < minv)
     {
       if (n < minv)
         {
           n = n * 10.0 ;
           neval --;
         }
     }
   while (scale_flag && n > 0.0 && n > maxv)
     {
       if (n > maxv)
         {
           n = n / 10.0 ;
           neval ++;
         }
     }

  /* It is time to process the EXP part of the number. 
     Value of 'nesign' is 0 unless following codes is executed.
  */
  if (ft != FMT_F)
    {
     /* Sign of the EXP value */
     if (neval >= 0)
       esign = SIGN_PLUS;
     else
       {
         esign = SIGN_MINUS;
         neval = - neval ;
       }

      /* Width of the EXP*/
      e_new = 0;
      j = neval;
      while (j > 0)
        {
           j = j / 10;
           e_new ++ ;
        }
      if (e <= e_new)
         e = e_new;

     /* Got the width of EXP */
     if (e < digits)
       e = digits ;

     /* Minimum value of the width would be 2 */
     if (e < 2)
       e = 2;

     nesign =  1 ;  /* We must give a position for the 'exp_char' */
     if (e > 0)
       nesign = e + nesign + (esign != SIGN_NONE ? 1 : 0);
   }


  intval = n;
  intstr = itoa (intval);
  intlen = strlen (intstr);

  q = rtoa (n, len, d);
  digits = strlen (q);

  /* Select a width if none was specified.  */
  if (w <= 0)
    w = digits + nsign;

  p = write_block (w);
  if (p == NULL)
    return;

  base = p;

  nblank = w - (nsign + intlen + d + nesign);
  if (nblank == -1 && ft != FMT_F)
     {
       with_exp = 0;
       nesign -= 1;
       nblank = w - (nsign + intlen + d + nesign);
     }
  /* don't let a leading '0' cause field overflow */
  if (nblank == -1 && ft == FMT_F && q[0] == '0')
     {
        q++;
        nblank = 0;
     }

  if (nblank < 0)
    {
      star_fill (p, w);
      goto done;
    }
  memset (p, ' ', nblank);
  p += nblank;

  switch (sign)
    {
    case SIGN_PLUS:
      *p++ = '+';
      break;
    case SIGN_MINUS:
      *p++ = '-';
      break;
    case SIGN_NONE:
      break;
    }

  memcpy (p, q, intlen + d + 1);
  p += intlen + d;

  if (nesign > 0)
    {
      if (with_exp)
         *p++ = exp_char;
      switch (esign)
        {
        case SIGN_PLUS:
          *p++ = '+';
          break;
        case SIGN_MINUS:
          *p++ = '-';
          break;
        case SIGN_NONE:
          break;
        }
      q = itoa (neval);
      digits = strlen (q);

      for (itmp = 0; itmp < e - digits; itmp++)
        *p++ = '0';
      memcpy (p, q, digits);
      p[digits]  = 0;
    }

done:
  return ;
}

void
write_l (fnode * f, char *source, int len)
{
  char *p;
  int64_t n;
                                                                                
  p = write_block (f->u.w);
  if (p == NULL)
    return;

  memset (p, ' ', f->u.w - 1);
  n = extract_int (source, len);
  p[f->u.w - 1] = (n) ? 'T' : 'F';
}

/* write_float() -- output a real number according to its format */

static void
write_float (fnode *f, const char *source, int len)
{
  double n;
  int nb =0, res;
  char * p, fin;
  fnode *f2 = NULL;

  n = extract_real (source, len);

  if (f->format != FMT_B && f->format != FMT_O && f->format != FMT_Z)
   {
     res = finite (n);
     if (res == 0)
       {
         nb =  f->u.real.w;
         if (nb <= 4)
            nb = 4;
         p = write_block (nb);
         memset (p, ' ' , 1);
         
         res = isinf (n);
         if (res != 0)
         {
            if (res > 0)
               fin = '+';
            else
               fin = '-';
         
             memset (p + 1, fin, nb - 1);
          }
         else
             sprintf(p + 1, "NaN");
         return;
       }
   }

  if (f->format != FMT_G)
    {
      output_float (f, n, len);
    }
  else
    {
      f2 = calculate_G_format(f, n, len, &nb);
      output_float (f2, n, len);
      if (f2 != NULL)
        free_mem(f2);

      if (nb > 0)
        {
          p = write_block (nb);
          memset (p, ' ', nb);
        }
   }
}


static void
write_int (fnode *f, const char *source, int len, char *(*conv) (uint64_t))
{
  uint32_t ns =0;
  uint64_t n = 0;
  int w, m, digits, nzero, nblank;
  char *p, *q;

  w = f->u.integer.w;
  m = f->u.integer.m;

  n = extract_int (source, len);

  /* Special case */

  if (m == 0 && n == 0)
    {
      if (w == 0)
        w = 1;

      p = write_block (w);
      if (p == NULL)
        return;

      memset (p, ' ', w);
      goto done;
    }


  if (len < 8)
     {
       ns = n;
       q = conv (ns);
     }
  else
      q = conv (n);

  digits = strlen (q);

  /* Select a width if none was specified.  The idea here is to always
   * print something. */

  if (w == 0)
    w = ((digits < m) ? m : digits);

  p = write_block (w);
  if (p == NULL)
    return;

  nzero = 0;
  if (digits < m)
    nzero = m - digits;

  /* See if things will work */

  nblank = w - (nzero + digits);

  if (nblank < 0)
    {
      star_fill (p, w);
      goto done;
    }

  memset (p, ' ', nblank);
  p += nblank;

  memset (p, '0', nzero);
  p += nzero;

  memcpy (p, q, digits);

done:
  return;
}

static void
write_decimal (fnode *f, const char *source, int len, char *(*conv) (int64_t))
{
  int64_t n = 0;
  int w, m, digits, nsign, nzero, nblank;
  char *p, *q;
  sign_t sign;

  w = f->u.integer.w;
  m = f->u.integer.m;

  n = extract_int (source, len);

  /* Special case */

  if (m == 0 && n == 0)
    {
      if (w == 0)
        w = 1;

      p = write_block (w);
      if (p == NULL)
        return;

      memset (p, ' ', w);
      goto done;
    }

  sign = calculate_sign (n < 0);
  if (n < 0)
    n = -n;

  nsign = sign == SIGN_NONE ? 0 : 1;
  q = conv (n);

  digits = strlen (q);

  /* Select a width if none was specified.  The idea here is to always
   * print something. */

  if (w == 0)
    w = ((digits < m) ? m : digits) + nsign;

  p = write_block (w);
  if (p == NULL)
    return;

  nzero = 0;
  if (digits < m)
    nzero = m - digits;

  /* See if things will work */

  nblank = w - (nsign + nzero + digits);

  if (nblank < 0)
    {
      star_fill (p, w);
      goto done;
    }

  memset (p, ' ', nblank);
  p += nblank;

  switch (sign)
    {
    case SIGN_PLUS:
      *p++ = '+';
      break;
    case SIGN_MINUS:
      *p++ = '-';
      break;
    case SIGN_NONE:
      break;
    }

  memset (p, '0', nzero);
  p += nzero;

  memcpy (p, q, digits);

done:
  return;
}


/* otoa()-- Convert unsigned octal to ascii */

static char *
otoa (uint64_t n)
{
  char *p;

  if (n == 0)
    {
      scratch[0] = '0';
      scratch[1] = '\0';
      return scratch;
    }

  p = scratch + sizeof (SCRATCH_SIZE) - 1;
  *p-- = '\0';

  while (n != 0)
    {
      *p = '0' + (n & 7);
      p -- ;
      n >>= 3;
    }

  return ++p;
}


/* btoa()-- Convert unsigned binary to ascii */

static char *
btoa (uint64_t n)
{
  char *p;

  if (n == 0)
    {
      scratch[0] = '0';
      scratch[1] = '\0';
      return scratch;
    }

  p = scratch + sizeof (SCRATCH_SIZE) - 1;
  *p-- = '\0';

  while (n != 0)
    {
      *p-- = '0' + (n & 1);
      n >>= 1;
    }

  return ++p;
}


void
write_i (fnode * f, const char *p, int len)
{

  write_decimal (f, p, len, (void *) itoa);
}


void
write_b (fnode * f, const char *p, int len)
{

  write_int (f, p, len, btoa);
}


void
write_o (fnode * f, const char *p, int len)
{

  write_int (f, p, len, otoa);
}

void
write_z (fnode * f, const char *p, int len)
{

  write_int (f, p, len, xtoa);
}


void
write_d (fnode *f, const char *p, int len)
{
  write_float (f, p, len);
}


void
write_e (fnode *f, const char *p, int len)
{
  write_float (f, p, len);
}


void
write_f (fnode *f, const char *p, int len)
{
  write_float (f, p, len);
}


void
write_en (fnode *f, const char *p, int len)
{
  write_float (f, p, len);
}


void
write_es (fnode *f, const char *p, int len)
{
  write_float (f, p, len);
}


/* write_x()-- Take care of the X/TR descriptor */

void
write_x (fnode * f)
{
  char *p;

  p = write_block (f->u.n);
  if (p == NULL)
    return;

  memset (p, ' ', f->u.n);
}


/* List-directed writing */


/* write_char()-- Write a single character to the output.  Returns
 * nonzero if something goes wrong. */

static int
write_char (char c)
{
  char *p;

  p = write_block (1);
  if (p == NULL)
    return 1;

  *p = c;

  return 0;
}


/* write_logical()-- Write a list-directed logical value */
/* Default logical output should be L2
  according to DEC fortran Manual. */
static void
write_logical (const char *source, int length)
{
  write_char (' ');
  write_char (extract_int (source, length) ? 'T' : 'F');
}


/* write_integer()-- Write a list-directed integer value. */

static void
write_integer (const char *source, int length)
{
  char *p;
  const char *q;
  int digits;
  int width = 12;

  q = itoa (extract_int (source, length));

  digits = strlen (q);

  if(width < digits )
    width = digits ;
  p = write_block (width) ;

  memset(p ,' ', width - digits) ;
  memcpy (p + width - digits, q, digits);
}


/* write_character()-- Write a list-directed string.  We have to worry
 * about delimiting the strings if the file has been opened in that
 * mode. */

static void
write_character (const char *source, int length)
{
  int i, extra;
  char *p, d;

  switch (current_unit->flags.delim)
    {
    case DELIM_APOSTROPHE:
      d = '\'';
      break;
    case DELIM_QUOTE:
      d = '"';
      break;
    default:
      d = ' ';
      break;
    }

  if (d == ' ')
    extra = 0;
  else
    {
      extra = 2;

      for (i = 0; i < length; i++)
	if (source[i] == d)
	  extra++;
    }

  p = write_block (length + extra);
  if (p == NULL)
    return;

  if (d == ' ')
    memcpy (p, source, length);
  else
    {
      *p++ = d;

      for (i = 0; i < length; i++)
	{
	  *p++ = source[i];
	  if (source[i] == d)
	    *p++ = d;
	}

      *p = d;
    }
}


/* Output the Real number with default format.
   According to DEC fortran LRM, default format for
   REAL(4) is 1PG15.7E2, and for REAL(8) is 1PG25.15E3  */

static void
write_real (const char *source, int length)
{
  fnode f ;
  int org_scale = g.scale_factor;
  f.format = FMT_G;
  g.scale_factor = 1;
  if (length < 8)
    {
      f.u.real.w = 15;
      f.u.real.d = 7;
      f.u.real.e = 2;
    }
  else
    {
      f.u.real.w = 24;
      f.u.real.d = 15;
      f.u.real.e = 3;
    }
  write_float (&f, source , length);
  g.scale_factor = org_scale;
}


static void
write_complex (const char *source, int len)
{

  if (write_char ('('))
    return;
  write_real (source, len);

  if (write_char (','))
    return;
  write_real (source + len, len);

  write_char (')');
}


/* write_separator()-- Write the separator between items. */

static void
write_separator (void)
{
  char *p;

  p = write_block (options.separator_len);
  if (p == NULL)
    return;

  memcpy (p, options.separator, options.separator_len);
}


/* list_formatted_write()-- Write an item with list formatting.
 * TODO: handle skipping to the next record correctly, particularly
 * with strings. */

void
list_formatted_write (bt type, void *p, int len)
{
  static int char_flag;

  if (current_unit == NULL)
    return;

  if (g.first_item)
    {
      g.first_item = 0;
      char_flag = 0;
    }
  else
    {
      if (type != BT_CHARACTER || !char_flag ||
	  current_unit->flags.delim != DELIM_NONE)
	write_separator ();
    }

  switch (type)
    {
    case BT_INTEGER:
      write_integer (p, len);
      break;
    case BT_LOGICAL:
      write_logical (p, len);
      break;
    case BT_CHARACTER:
      write_character (p, len);
      break;
    case BT_REAL:
      write_real (p, len);
      break;
    case BT_COMPLEX:
      write_complex (p, len);
      break;
    default:
      internal_error ("list_formatted_write(): Bad type");
    }

  char_flag = (type == BT_CHARACTER);
}

void
namelist_write (void)
{
   namelist_info * t1, *t2;
   int len,num;
   void * p;

   num = 0;
   write_character("&",1);
   write_character (ioparm.namelist_name, ioparm.namelist_name_len);
   write_character("\n",1);

   if (ionml != NULL)
     {
       t1 = ionml;
       while (t1 != NULL)
        {
          num ++;
          t2 = t1;
          t1 = t1->next;
          write_character(t2->var_name, strlen(t2->var_name));
          write_character("=",1);
          len = t2->len;
          p = t2->mem_pos;
          switch (t2->type)
            {
            case BT_INTEGER:
              write_integer (p, len);
              break;
            case BT_LOGICAL:
              write_logical (p, len);
              break;
            case BT_CHARACTER:
              write_character (p, len);
              break;
            case BT_REAL:
              write_real (p, len);
              break;
            case BT_COMPLEX:
              write_complex (p, len);
              break;
            default:
              internal_error ("Bad type for namelist write");
            }
         write_character(",",1);
         if (num > 5)
           {
              num = 0;
              write_character("\n",1);
           }
        }
     }
     write_character("/",1);

}