#include <defs.h>


static int
define_utf8( mcpu_macro_table *table, const char *name,
             const char *replacement )
{
  mcpu_text n;
  mcpu_text r;
  int       rc = -1;

  mcpu_text_init( &n );
  mcpu_text_init( &r );

  if( mcpu_text_from_utf8(&n, name) != 0 ||
      mcpu_text_from_utf8(&r, replacement ? replacement : "") != 0 )
    goto done;

  rc = mcpu_macro_define_object( table, n.data, n.length,
                                 r.data, r.length,
                                 MCPU_MACRO_ORIGIN_BUILTIN );

done:
  mcpu_text_free( &n );
  mcpu_text_free( &r );
  return( rc );
}


static int
define_unsigned( mcpu_macro_table *table, const char *name,
                 unsigned long value )
{
  char text[64];

  snprintf( text, sizeof(text), "%lu", value );
  return( define_utf8(table, name, text) );
}


static int
define_quoted( mcpu_macro_table *table, const char *name,
               const char *value )
{
  size_t n;
  char  *text;
  size_t i;
  size_t o = 0;
  int    rc;

  if( value == NULL )
    value = "";

  n = strlen( value );
  if( n > (SIZE_MAX - 3) / 2 )
  {
    errno = EOVERFLOW;
    return( -1 );
  }

  text = (char *)malloc( n * 2 + 3 );
  if( text == NULL )
    return( -1 );

  text[o++] = '"';
  for( i = 0; i < n; ++i )
  {
    if( value[i] == '\\' || value[i] == '"' )
      text[o++] = '\\';
    text[o++] = value[i];
  }
  text[o++] = '"';
  text[o] = 0;

  rc = define_utf8( table, name, text );
  free( text );
  return( rc );
}


static int
define_from_macro( mcpu_macro_table *table, const char *name,
                   const char *source_name )
{
  mcpu_text   source;
  mcpu_text   target;
  mcpu_macro *macro;
  int         rc = -1;

  mcpu_text_init( &source );
  mcpu_text_init( &target );

  if( mcpu_text_from_utf8(&source, source_name) != 0 ||
      mcpu_text_from_utf8(&target, name) != 0 )
    goto done;

  macro = mcpu_macro_find( table, source.data, source.length );
  if( macro == NULL || macro->builtin != MCPU_MACRO_BUILTIN_NONE )
  {
    errno = EINVAL;
    goto done;
  }

  rc = mcpu_macro_define_object( table, target.data, target.length,
                                 macro->replacement,
                                 macro->replacement_length,
                                 MCPU_MACRO_ORIGIN_BUILTIN );

done:
  mcpu_text_free( &source );
  mcpu_text_free( &target );
  return( rc );
}


static int
define_sized_builtin_utf8( mcpu_macro_table *table, const char *name,
                           enum mcpu_macro_builtin builtin, unsigned bits )
{
  mcpu_text n;
  int       rc;

  mcpu_text_init( &n );
  if( mcpu_text_from_utf8(&n, name) != 0 )
    return( -1 );

  rc = mcpu_macro_define_sized_builtin( table, n.data, n.length,
                                        builtin, bits );
  mcpu_text_free( &n );
  return( rc );
}


static unsigned long
mcpp_uint_decimal_digs( unsigned bits )
{
  uint64_t n;

  if( bits < 1 )
    return( 0 );

  /*
   * Number of decimal digits in 2^bits - 1.  This follows the integer-only
   * scheme used by LibMPU _int_digs(), but does not include a terminating
   * NUL.  The tighter upper approximation keeps the result exact for every
   * integer width supported by the current LibMPU family through 65536 bits.
   *
   *   log10(2) < 301029995664 / 1000000000000
   */
  n = ((uint64_t)bits * UINT64_C(301029995664) +
       UINT64_C(999999999999)) / UINT64_C(1000000000000);

  return( (unsigned long)n );
}


static unsigned long
mcpp_int_decimal_digs( unsigned bits )
{
  if( bits < 2 )
    return( 0 );

  /* Signed maximum is 2^(bits - 1) - 1; sign is not part of DECIMAL_DIG. */
  return( mcpp_uint_decimal_digs(bits - 1) );
}


static int
define_fixed_integer_family( mcpu_macro_table *table, unsigned bits )
{
  size_t   nb = (size_t)bits / 8;
  mpu_int *value = NULL;
  char    *text = NULL;
  char     name[96];
  size_t   text_size;
  unsigned long int_digs;
  unsigned long uint_digs;
  int      rc = -1;

  if( bits == 0 || (bits % 8) != 0 )
  {
    errno = EINVAL;
    return( -1 );
  }

  snprintf( name, sizeof(name), "__INT%u_TYPE__", bits );
  {
    char type[64];
    snprintf( type, sizeof(type), "int%u", bits );
    if( define_utf8(table, name, type) != 0 )
      return( -1 );
  }

  snprintf( name, sizeof(name), "__UINT%u_TYPE__", bits );
  {
    char type[64];
    snprintf( type, sizeof(type), "uint%u", bits );
    if( define_utf8(table, name, type) != 0 )
      return( -1 );
  }

  snprintf( name, sizeof(name), "__INT%u_WIDTH__", bits );
  if( define_unsigned(table, name, bits) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__UINT%u_WIDTH__", bits );
  if( define_unsigned(table, name, bits) != 0 )
    return( -1 );

  /*
   * TYPE/WIDTH/SIZEOF and decimal-digit metadata remain available for the
   * complete LibMPU integer family through NB_I_MAX * 8.  Only textual MAX
   * values are capped at 256 bits so -dMP stays compact and useful.
   */
  snprintf( name, sizeof(name), "__SIZEOF_INT%u__", bits );
  if( define_unsigned(table, name, bits / 8) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__SIZEOF_UINT%u__", bits );
  if( define_unsigned(table, name, bits / 8) != 0 )
    return( -1 );

  int_digs = mcpp_int_decimal_digs( bits );
  uint_digs = mcpp_uint_decimal_digs( bits );
  if( int_digs == 0 || uint_digs == 0 )
  {
    errno = EINVAL;
    return( -1 );
  }
  snprintf( name, sizeof(name), "__INT%u_DECIMAL_DIG__", bits );
  if( define_unsigned(table, name, int_digs) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__UINT%u_DECIMAL_DIG__", bits );
  if( define_unsigned(table, name, uint_digs) != 0 )
    return( -1 );

  if( bits > 256 )
    return( 0 );

  value = (mpu_int *)malloc( nb );
  if( value == NULL )
    return( -1 );

  text_size = (size_t)bits + 3;
  text = (char *)calloc( text_size, 1 );
  if( text == NULL )
    goto done;

  memset( value, 0xff, nb );
  iuitoa( (__mpu_char8_t *)text, value, RADIX_HEX, LOWERCASE, (int)nb );

  snprintf( name, sizeof(name), "__UINT%u_MAX__", bits );
  if( define_utf8(table, name, text) != 0 )
    goto done;

  /*
   * iuitoa() is the canonical LibMPU conversion.  For the signed maximum
   * the all-ones unsigned bit pattern has only its top bit cleared.
   */
  if( strlen(text) < 3 || text[0] != '0' || text[1] != 'x' )
  {
    errno = EINVAL;
    goto done;
  }
  text[2] = '7';

  snprintf( name, sizeof(name), "__INT%u_MAX__", bits );
  if( define_utf8(table, name, text) != 0 )
    goto done;

  rc = 0;

done:
  free( text );
  free( value );
  return( rc );
}

typedef void (*real_value_fn)( mpu_real *, unsigned int, int );

static int
append_real_value( mcpu_text *output, unsigned bits, real_value_fn fn )
{
  int       nb = (int)(bits / 8);
  int       max_string;
  mpu_real *value;
  char     *text;
  int       rc = -1;

  max_string = _real_max_string( nb );
  if( max_string <= 0 )
  {
    errno = EINVAL;
    return( -1 );
  }

  value = (mpu_real *)calloc( (size_t)nb, 1 );
  text = (char *)calloc( (size_t)max_string + 4096, 1 );
  if( value == NULL || text == NULL )
    goto done;

  fn( value, 0, nb );
  real_to_ascii( (__mpu_char8_t *)text, value,
                 _real_mant_digs(nb), 'e', 0, 0, nb );
  if( text[0] == 0 )
  {
    errno = EINVAL;
    goto done;
  }

  rc = mcpu_text_append_ascii( output, text );

done:
  free( text );
  free( value );
  return( rc );
}


static void
real_epsilon_wrapper( mpu_real *value, unsigned int sign, int nb )
{
  (void)sign;
  _real_epsilon( value, nb );
}


static int
append_real_exponent( mcpu_text *output, unsigned bits,
                      void (*fn)(mpu_int *, int, int) )
{
  int      nb_r = (int)(bits / 8);
  int      nb_e = _sizeof_exp( nb_r );
  mpu_int *value;
  char    *text;
  size_t   text_size;
  int      rc = -1;

  if( nb_e <= 0 )
  {
    errno = EINVAL;
    return( -1 );
  }

  value = (mpu_int *)calloc( (size_t)nb_e, 1 );
  text_size = (size_t)nb_e * 8 + 3;
  text = (char *)calloc( text_size, 1 );
  if( value == NULL || text == NULL )
    goto done;

  fn( value, nb_e, nb_r );
  iitoa( (__mpu_char8_t *)text, value, RADIX_DEC, LOWERCASE, nb_e );
  if( text[0] == 0 )
  {
    errno = EINVAL;
    goto done;
  }

  rc = mcpu_text_append_ascii( output, text );

done:
  free( text );
  free( value );
  return( rc );
}


static int
define_real_family( mcpu_macro_table *table, unsigned bits )
{
  char name[96];
  char type[64];
  int  nb = (int)(bits / 8);

  /*
   * Real and Complex language types exist only through the configured
   * MPU_REAL_IO_LIMIT.  Complex WIDTH is the width parameter in the language
   * type name (complex128 -> 128), while SIZEOF is twice the Real storage.
   */
  if( bits > MCPU_CPP_MPU_REAL_IO_LIMIT )
    return( 0 );

  snprintf( name, sizeof(name), "__REAL%u_TYPE__", bits );
  snprintf( type, sizeof(type), "real%u", bits );
  if( define_utf8(table, name, type) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__COMPLEX%u_TYPE__", bits );
  snprintf( type, sizeof(type), "complex%u", bits );
  if( define_utf8(table, name, type) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__REAL%u_WIDTH__", bits );
  if( define_unsigned(table, name, bits) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__COMPLEX%u_WIDTH__", bits );
  if( define_unsigned(table, name, bits) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__SIZEOF_REAL%u__", bits );
  if( define_unsigned(table, name, bits / 8) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__SIZEOF_COMPLEX%u__", bits );
  if( define_unsigned(table, name, bits / 4) != 0 )
    return( -1 );

  /*
   * These are compact structural/text-conversion properties.  They are
   * available for every configured Real type through MPU_REAL_IO_LIMIT.
   * _real_max_string() returns a character count, not a byte count.
   */
  {
    int exp_size = _sizeof_exp( nb );
    int max_strlen = _real_max_string( nb );

    if( exp_size <= 0 || max_strlen <= 0 )
    {
      errno = EINVAL;
      return( -1 );
    }

    snprintf( name, sizeof(name), "__SIZEOF_REAL%u_EXP__", bits );
    if( define_unsigned(table, name, (unsigned long)exp_size) != 0 )
      return( -1 );

    snprintf( name, sizeof(name), "__REAL%u_MAX_STRLEN__", bits );
    if( define_unsigned(table, name, (unsigned long)max_strlen) != 0 )
      return( -1 );
  }

  /*
   * Precision metadata is compact and is useful for every configured Real
   * width.  Only large textual numeric values are capped at 256 bits.
   */
  snprintf( name, sizeof(name), "__REAL%u_MANT_DIG__", bits );
  if( define_unsigned(table, name, (unsigned long)_real_mant_digs(nb)) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__REAL%u_DECIMAL_DIG__", bits );
  if( define_unsigned(table, name, (unsigned long)_real_digs(nb)) != 0 )
    return( -1 );

  if( bits > 256 )
    return( 0 );

  snprintf( name, sizeof(name), "__REAL%u_MAX__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MAX, bits) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__REAL%u_MIN__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MIN, bits) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__REAL%u_EPSILON__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_EPSILON, bits) != 0 )
    return( -1 );

  snprintf( name, sizeof(name), "__REAL%u_MAX_EXP__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MAX_EXP, bits) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__REAL%u_MIN_EXP__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MIN_EXP, bits) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__REAL%u_MAX_10_EXP__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MAX_10_EXP, bits) != 0 )
    return( -1 );
  snprintf( name, sizeof(name), "__REAL%u_MIN_10_EXP__", bits );
  if( define_sized_builtin_utf8(table, name,
                                MCPU_MACRO_BUILTIN_REAL_MIN_10_EXP, bits) != 0 )
    return( -1 );

  return( 0 );
}

int
mcpu_predefined_expand_builtin( enum mcpu_macro_builtin builtin,
                                unsigned bits,
                                mcpu_text *output )
{
  if( output == NULL || bits == 0 || bits > 256 ||
      bits > MCPU_CPP_MPU_REAL_IO_LIMIT )
  {
    errno = EINVAL;
    return( -1 );
  }

  switch( builtin )
  {
    case MCPU_MACRO_BUILTIN_REAL_MAX:
      return( append_real_value(output, bits, _real_max) );
    case MCPU_MACRO_BUILTIN_REAL_MIN:
      return( append_real_value(output, bits, _real_min) );
    case MCPU_MACRO_BUILTIN_REAL_EPSILON:
      return( append_real_value(output, bits, real_epsilon_wrapper) );
    case MCPU_MACRO_BUILTIN_REAL_MAX_EXP:
      return( append_real_exponent(output, bits, _real_max_exp) );
    case MCPU_MACRO_BUILTIN_REAL_MIN_EXP:
      return( append_real_exponent(output, bits, _real_min_exp) );
    case MCPU_MACRO_BUILTIN_REAL_MAX_10_EXP:
      return( append_real_exponent(output, bits, _real_max_10_exp) );
    case MCPU_MACRO_BUILTIN_REAL_MIN_10_EXP:
      return( append_real_exponent(output, bits, _real_min_10_exp) );
    default:
      errno = EINVAL;
      return( -1 );
  }
}


int
mcpu_predefined_install( mcpu_macro_table *table )
{
  unsigned bits;
  char     type[64];
  char     ref[96];

  if( table == NULL )
  {
    errno = EINVAL;
    return( -1 );
  }

  if( define_utf8(table, "_ARCH_MCPU", "1") != 0 ||
      define_quoted(table, "__MCPU_CPP_VERSION__", PACKAGE_VERSION) != 0 ||
      define_utf8(table, "__REGISTER_PREFIX__", "") != 0 ||
      define_utf8(table, "__LOCAL_LABEL_PREFIX__", "") != 0 ||
      define_utf8(table, "__USER_LABEL_PREFIX__", "") != 0 ||
      define_utf8(table, "__IMMEDIATE_PREFIX__", "") != 0 ||
      define_utf8(table, "__ORDER_LITTLE_ENDIAN__", "1234") != 0 ||
      define_utf8(table, "__ORDER_BIG_ENDIAN__", "4321") != 0 ||
      define_utf8(table, "__ORDER_PDP_ENDIAN__", "3412") != 0 )
    return( -1 );

#if MCPU_CPP_MPU_BYTE_ORDER == 1234
  if( define_utf8(table, "__MCPU_BYTE_ORDER__", "__ORDER_LITTLE_ENDIAN__") != 0 )
    return( -1 );
#else
  if( define_utf8(table, "__MCPU_BYTE_ORDER__", "__ORDER_BIG_ENDIAN__") != 0 )
    return( -1 );
#endif
  if( define_utf8(table, "__BYTE_ORDER__", "__MCPU_BYTE_ORDER__") != 0 )
    return( -1 );

#if MCPU_CPP_MPU_WORD_ORDER == 1234
  if( define_utf8(table, "__MCPU_WORD_ORDER__", "__ORDER_LITTLE_ENDIAN__") != 0 )
    return( -1 );
#else
  if( define_utf8(table, "__MCPU_WORD_ORDER__", "__ORDER_BIG_ENDIAN__") != 0 )
    return( -1 );
#endif

  if( define_unsigned(table, "__MCPU_MACHINE_REGISTER_WIDTH__",
                       MCPU_CPP_MPU_REGISTER_WIDTH) != 0 ||
      define_unsigned(table, "__MCPU_REAL_IO_LIMIT__",
                       MCPU_CPP_MPU_REAL_IO_LIMIT) != 0 ||
      define_unsigned(table, "__MCPU_MATH_FN_LIMIT__",
                       MCPU_CPP_MPU_MATH_FN_LIMIT) != 0 ||
      define_unsigned(table, "__MCPU_INT_MAX_WIDTH__",
                       MCPU_CPP_MPU_INT_MAX_WIDTH) != 0 ||
      define_unsigned(table, "__MCPU_REAL_MAX_WIDTH__",
                       MCPU_CPP_MPU_REAL_IO_LIMIT) != 0 ||
      define_unsigned(table, "__MCPU_COMPLEX_MAX_WIDTH__",
                       MCPU_CPP_MPU_REAL_IO_LIMIT) != 0 ||
      define_unsigned(table, "__SIZEOF_POINTER__", 8) != 0 ||
      define_unsigned(table, "__MCPU_POINTER_WIDTH__", 64) != 0 ||
      define_unsigned(table, "__MCPU_SIZEOF_SIZE__", MCPU_CPP_SIZEOF_SIZE_T) != 0 ||
      define_unsigned(table, "__MCPU_SIZE_WIDTH__", MCPU_CPP_SIZE_WIDTH) != 0 ||
      define_unsigned(table, "__SIZEOF_PTRDIFF__", 8) != 0 ||
      define_unsigned(table, "__PTRDIFF_WIDTH__", 64) != 0 ||
      define_utf8(table, "__CHAR8_TYPE__", "char8") != 0 ||
      define_utf8(table, "__CHAR16_TYPE__", "char16") != 0 ||
      define_unsigned(table, "__CHAR8_WIDTH__", 8) != 0 ||
      define_unsigned(table, "__CHAR16_WIDTH__", 16) != 0 ||
      define_unsigned(table, "__SIZEOF_CHAR8__", 1) != 0 ||
      define_unsigned(table, "__SIZEOF_CHAR16__", 2) != 0 ||
      define_utf8(table, "__CHAR8_MAX__", "0xff") != 0 ||
      define_utf8(table, "__CHAR16_MAX__", "0xffff") != 0 )
    return( -1 );

  for( bits = 8; bits != 0 && bits <= MCPU_CPP_MPU_INT_MAX_WIDTH; bits *= 2 )
  {
    if( define_fixed_integer_family(table, bits) != 0 )
      return( -1 );
  }

  snprintf( type, sizeof(type), "uint%u", (unsigned)MCPU_CPP_SIZE_WIDTH );
  if( define_utf8(table, "__MCPU_SIZE_TYPE__", type) != 0 )
    return( -1 );
  snprintf( ref, sizeof(ref), "__UINT%u_MAX__", (unsigned)MCPU_CPP_SIZE_WIDTH );
  if( define_from_macro(table, "__MCPU_SIZE_MAX__", ref) != 0 )
    return( -1 );

  snprintf( type, sizeof(type), "int%u", (unsigned)MCPU_CPP_SSIZE_WIDTH );
  if( define_utf8(table, "__MCPU_SSIZE_TYPE__", type) != 0 ||
      define_unsigned(table, "__MCPU_SSIZE_WIDTH__", MCPU_CPP_SSIZE_WIDTH) != 0 ||
      define_unsigned(table, "__MCPU_SIZEOF_SSIZE__", MCPU_CPP_SIZEOF_SSIZE_T) != 0 )
    return( -1 );
  if( MCPU_CPP_SSIZE_WIDTH <= 256 )
  {
    snprintf( ref, sizeof(ref), "__INT%u_MAX__", (unsigned)MCPU_CPP_SSIZE_WIDTH );
    if( define_from_macro(table, "__MCPU_SSIZE_MAX__", ref) != 0 )
      return( -1 );
  }

  if( define_utf8(table, "__PTRDIFF_TYPE__", "int64") != 0 ||
      define_unsigned(table, "__PTRDIFF_WIDTH__", 64) != 0 ||
      define_utf8(table, "__PTRDIFF_MAX__", "0x7fffffffffffffff") != 0 ||
      define_utf8(table, "__INTPTR_TYPE__", "int64") != 0 ||
      define_utf8(table, "__UINTPTR_TYPE__", "uint64") != 0 ||
      define_unsigned(table, "__INTPTR_WIDTH__", 64) != 0 ||
      define_unsigned(table, "__UINTPTR_WIDTH__", 64) != 0 ||
      define_utf8(table, "__INTPTR_MAX__", "0x7fffffffffffffff") != 0 ||
      define_utf8(table, "__UINTPTR_MAX__", "0xffffffffffffffff") != 0 )
    return( -1 );

  for( bits = 32; bits != 0 && bits <= MCPU_CPP_MPU_REAL_IO_LIMIT; bits *= 2 )
  {
    if( define_real_family(table, bits) != 0 )
      return( -1 );
  }

  return( 0 );
}