/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB

   This program 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 of the License, or
   (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

#include <my_global.h>
#include <m_string.h>
#include <stdlib.h>
#include <my_getopt.h>
#include <assert.h>
#include <my_sys.h>

static int findopt (char *optpat, uint length,
		    const struct my_option **opt_res,
		    char **ffname);
static my_bool compare_strings (register const char *s, register const char *t,
				uint length);
static longlong getopt_ll (char *arg, const struct my_option *optp, int *err);
static ulonglong getopt_ull (char *arg, const struct my_option *optp,
			     int *err);
static void init_variables(const struct my_option *options);
static int setval (const struct my_option *opts, char *argument,
		   my_bool set_maximum_value);

#define DISABLE_OPTION_COUNT      2 /* currently 'skip' and 'disable' below */

/* 'disable'-option prefixes must be in the beginning, DISABLE_OPTION_COUNT
   is the number of disabling prefixes */
static const char *special_opt_prefix[]=
{"skip", "disable", "enable", "maximum", "loose", 0};

char *disabled_my_option= (char*) "0";

/* Return error values from handle_options */

#define ERR_UNKNOWN_OPTION        1
#define ERR_AMBIGUOUS_OPTION      2
#define ERR_NO_ARGUMENT_ALLOWED   3
#define ERR_ARGUMENT_REQUIRED     4
#define ERR_VAR_PREFIX_NOT_UNIQUE 5
#define ERR_UNKNOWN_VARIABLE      6
#define ERR_OUT_OF_MEMORY         7
#define ERR_UNKNOWN_SUFFIX        8
#define ERR_NO_PTR_TO_VARIABLE	  9


/* 
  function: handle_options

  Sort options; put options first, until special end of options (--), or
  until end of argv. Parse options; check that the given option matches with
  one of the options in struct 'my_option', return error in case of ambiguous
  or unknown option. Check that option was given an argument if it requires
  one. Call function 'get_one_option()' once for each option.
*/

int handle_options(int *argc, char ***argv, 
		   const struct my_option *longopts, 
		   my_bool (*get_one_option)(int,
					     const struct my_option *,
					     char *))
{
  uint opt_found, argvpos= 0, length, spec_len, i;
  my_bool end_of_options= 0, must_be_var, set_maximum_value, special_used,
          option_is_loose;
  char *progname= *(*argv), **pos, *optend, *prev_found;
  const struct my_option *optp;
  int error;

  LINT_INIT(opt_found);
  (*argc)--; /* Skip the program name */
  (*argv)++; /*      --- || ----      */
  init_variables(longopts);

  for (pos= *argv; *pos; pos++)
  {
    char *cur_arg= *pos;
    if (cur_arg[0] == '-' && cur_arg[1] && !end_of_options) /* must be opt */
    {
      char *argument=    0;
      must_be_var=       0;
      set_maximum_value= 0;
      special_used=      0;
      option_is_loose=   0;

      cur_arg++;		/* skip '-' */
      if (*cur_arg == '-' || *cur_arg == 'O') /* check for long option, */
      {                                       /* --set-variable, or -O  */
	if (*cur_arg == 'O')
	{
	  must_be_var= 1;

	  if (!(*++cur_arg))	/* If not -Ovar=# */
	  {
	    /* the argument must be in next argv */
	    if (!*++pos)
	    {
	      fprintf(stderr, "%s: Option '-O' requires an argument\n",
		      progname);
	      return ERR_ARGUMENT_REQUIRED;
	    }
	    cur_arg= *pos;
	    (*argc)--;
	  }
	}
	else if (!compare_strings(cur_arg, "-set-variable", 13) ||
		 !compare_strings(cur_arg, "-loose-set-variable", 19))
	{
	  must_be_var= 1;
	  if (cur_arg[1] == 'l')
	  {
	    option_is_loose= 1;
	    cur_arg+= 6;
	  }
	  if (cur_arg[13] == '=')
	  {
	    cur_arg+= 14;
	    if (!*cur_arg)
	    {
	      fprintf(stderr,
		      "%s: Option '--set-variable' requires an argument\n",
		      progname);
	      return ERR_ARGUMENT_REQUIRED;
	    }
	  }
	  else if (cur_arg[14]) /* garbage, or another option. break out */
	    must_be_var= 0;
	  else
	  {
	    /* the argument must be in next argv */
	    if (!*++pos)
	    {
	      fprintf(stderr,
		      "%s: Option '--set-variable' requires an argument\n",
		      progname);
	      return ERR_ARGUMENT_REQUIRED;
	    }
	    cur_arg= *pos;
	    (*argc)--;
	  }
	}
	else if (!must_be_var)
	{
	  if (!*++cur_arg)	/* skip the double dash */
	  {
	    /* '--' means end of options, look no further */
	    end_of_options= 1;
	    (*argc)--;
	    continue;
	  }
	}
	optend= strcend(cur_arg, '=');
	length= optend - cur_arg;
	if (*optend == '=')
	  optend++;
	else
	  optend=0;

	/*
	  Find first the right option. Return error in case of an ambiguous,
	  or unknown option
	*/
	optp= longopts;
	if (!(opt_found= findopt(cur_arg, length, &optp, &prev_found)))
	{
	  /*
	    Didn't find any matching option. Let's see if someone called
	    option with a special option prefix
	  */
	  if (!must_be_var)
	  {
	    if (optend)
	      must_be_var= 1; /* option is followed by an argument */
	    for (i= 0; special_opt_prefix[i]; i++)
	    {
	      spec_len= strlen(special_opt_prefix[i]);
	      if (!compare_strings(special_opt_prefix[i], cur_arg, spec_len) &&
		  cur_arg[spec_len] == '-')
	      {
		/*
		  We were called with a special prefix, we can reuse opt_found
		*/
		special_used= 1;
		cur_arg+= (spec_len + 1);
		if (!compare_strings(special_opt_prefix[i], "loose", 5))
		  option_is_loose= 1;
		if ((opt_found= findopt(cur_arg, length - (spec_len + 1),
					&optp, &prev_found)))
		{
		  if (opt_found > 1)
		  {
		    fprintf(stderr,
			    "%s: ambiguous option '--%s-%s' (--%s-%s)\n",
			    progname, special_opt_prefix[i], cur_arg,
			    special_opt_prefix[i], prev_found);
		    return ERR_AMBIGUOUS_OPTION;
		  }
		  if (i < DISABLE_OPTION_COUNT)
		    optend= disabled_my_option;
		  else if (!compare_strings(special_opt_prefix[i],"enable",6))
		    optend= (char*) "1";
		  else if (!compare_strings(special_opt_prefix[i],"maximum",7))
		  {
		    set_maximum_value= 1;
		    must_be_var= 1;
		  }
		  break; /* break from the inner loop, main loop continues */
		}
	      }
	    }
	  }
	  if (!opt_found)
	  {
	    if (must_be_var)
	    {
	      fprintf(stderr,
		      "%s: %s: unknown variable '%s'\n", progname,
		      option_is_loose ? "WARNING" : "ERROR", cur_arg);
	      if (!option_is_loose)
		return ERR_UNKNOWN_VARIABLE;
	    }
	    else
	    {
	      fprintf(stderr,
		      "%s: %s: unknown option '--%s'\n", progname,
		      option_is_loose ? "WARNING" : "ERROR", cur_arg);
	      if (!option_is_loose)
		return ERR_UNKNOWN_OPTION;
	    }
	    if (option_is_loose)
	    {
	      (*argc)--;
	      continue;
	    }
	  }
	}
	if (opt_found > 1)
	{
	  if (must_be_var)
	  {
	    fprintf(stderr, "%s: variable prefix '%s' is not unique\n",
		    progname, cur_arg);
	    return ERR_VAR_PREFIX_NOT_UNIQUE;
	  }
	  else
	  {
	    fprintf(stderr, "%s: ambiguous option '--%s' (%s, %s)\n",
		    progname, cur_arg, prev_found, optp->name);
	    return ERR_AMBIGUOUS_OPTION;
	  }
	}
	if (must_be_var && (!optp->value || optp->var_type == GET_BOOL))
	{
	  fprintf(stderr, "%s: option '%s' cannot take an argument\n",
		  progname, optp->name);
	  return ERR_NO_ARGUMENT_ALLOWED;
	}
	if (optp->arg_type == NO_ARG)
	{
	  if (optend && !special_used)
	  {
	    fprintf(stderr, "%s: option '--%s' cannot take an argument\n",
		    progname, optp->name);
	    return ERR_NO_ARGUMENT_ALLOWED;
	  }
	  if (optp->var_type == GET_BOOL)
	  {
	    /*
	      Set bool to 1 if no argument or if the user has used
	      --enable-'option-name'.
	      *optend was set to '0' if one used --disable-option
	      */
	    *((my_bool*) optp->value)= 	(my_bool) (!optend || *optend == '1');
	    (*argc)--;	    
	    continue; // For GET_BOOL get_one_option() shouldn't be called
	  }
	  argument= optend;
	}
	else if (optp->arg_type == OPT_ARG && optp->var_type == GET_BOOL)
	{
	  if (optend == disabled_my_option)
	    *((my_bool*) optp->value)= (my_bool) 0;
	  else
	  {
	    if (!optend) /* No argument -> enable option */
	      *((my_bool*) optp->value)= (my_bool) 1;
	    else /* If argument differs from 0, enable option, else disable */
	      *((my_bool*) optp->value)= (my_bool) atoi(optend) != 0;
	  }
	  (*argc)--;	    
	  continue;
	}
	else if (optp->arg_type == REQUIRED_ARG && !optend)
	{
	  /* Check if there are more arguments after this one */
	  if (!*++pos)
	  {
	    fprintf(stderr, "%s: option '--%s' requires an argument\n",
		    progname, optp->name);
	    return ERR_ARGUMENT_REQUIRED;
	  }
	  argument= *pos;
	  (*argc)--;
	}
	else
	  argument= optend;
      }
      else  /* must be short option */
      {
	for (optend= cur_arg; *optend; optend++, opt_found= 0)
	{
	  for (optp= longopts; optp->id; optp++)
	  {
	    if (optp->id == (int) (uchar) *optend)
	    {
	      /* Option recognized. Find next what to do with it */
	      opt_found= 1;
	      if (optp->var_type == GET_BOOL && optp->arg_type == NO_ARG)
	      {
		*((my_bool*) optp->value)= (my_bool) 1;
		(*argc)--;
		continue; // For GET_BOOL get_one_option() shouldn't be called
	      }
	      else if (optp->arg_type == REQUIRED_ARG ||
		       optp->arg_type == OPT_ARG)
	      {
		if (*(optend + 1))
		{
		  // The rest of the option is option argument
		  argument= optend + 1;
		  // This is in effect a jump out of the outer loop
		  optend= (char*) " ";
		}
		else if (optp->arg_type == REQUIRED_ARG)
		{
		  /* Check if there are more arguments after this one */
		  if (!*++pos)
		  {
		    fprintf(stderr, "%s: option '-%c' requires an argument\n",
			    progname, optp->id);
		    return ERR_ARGUMENT_REQUIRED;
		  }
		  argument= *pos;
		  (*argc)--;
		  /* the other loop will break, because *optend + 1 == 0 */
		}
	      }
	      if ((error= setval(optp, argument, set_maximum_value)))
	      {
		fprintf(stderr,
			"%s: Error while setting value '%s' to '%s'\n",
			progname, argument, optp->name);
		return error;
	      }
	      get_one_option(optp->id, optp, argument);
	      break;
	    }
	  }
	  if (!opt_found)
	  {
	    fprintf(stderr,
		    "%s: unknown option '-%c'\n", progname, *cur_arg);
	    return ERR_UNKNOWN_OPTION;
	  }
	}
	(*argc)--; /* option handled (short), decrease argument count */
	continue;
      }
      if ((error= setval(optp, argument, set_maximum_value)))
      {
	fprintf(stderr,
		"%s: Error while setting value '%s' to '%s'\n",
		progname, argument, optp->name);
	return error;
      }
      get_one_option(optp->id, optp, argument);

      (*argc)--; /* option handled (short or long), decrease argument count */
    }
    else /* non-option found */
      (*argv)[argvpos++]= cur_arg;
  }
  return 0;
}

/*
  function: setval

  Arguments: opts, argument
  Will set the option value to given value
*/

static int setval (const struct my_option *opts, char *argument,
		   my_bool set_maximum_value)
{
  int err= 0;

  if (opts->value && argument)
  {
    gptr *result_pos= (set_maximum_value) ?
      opts->u_max_value : opts->value;

    if (!result_pos)
      return ERR_NO_PTR_TO_VARIABLE;

    switch (opts->var_type) {
    case GET_INT:
    case GET_UINT:           /* fall through */
      *((int*) result_pos)= (int) getopt_ll(argument, opts, &err);
      break;
    case GET_LONG:
    case GET_ULONG:          /* fall through */
      *((long*) result_pos)= (long) getopt_ll(argument, opts, &err);
      break;
    case GET_LL:
      *((longlong*) result_pos)= getopt_ll(argument, opts, &err);
      break;
    case GET_ULL:
      *((ulonglong*) result_pos)= getopt_ull(argument, opts, &err);
      break;
    case GET_STR:
      *((char**) result_pos)= argument;
      break;
    case GET_STR_ALLOC:
      if ((*((char**) result_pos)))
	my_free((*(char**) result_pos),
		MYF(MY_WME | MY_FAE));
      if (!(*((char**) result_pos)= my_strdup(argument, MYF(MY_WME))))
	return ERR_OUT_OF_MEMORY;
      break;
    default:    /* dummy default to avoid compiler warnings */
      break;
    }
    if (err)
      return ERR_UNKNOWN_SUFFIX;
  }
  return 0;
}

/* 
  function: findopt

  Arguments: opt_pattern, length of opt_pattern, opt_struct, first found
  name (ffname)

  Go through all options in the my_option struct. Return number
  of options found that match the pattern and in the argument
  list the option found, if any. In case of ambiguous option, store
  the name in ffname argument
*/

static int findopt (char *optpat, uint length,
		    const struct my_option **opt_res,
		    char **ffname)
{
  int count;
  struct my_option *opt= (struct my_option *) *opt_res;

  for (count= 0; opt->name; opt++)
  {
    if (!compare_strings(opt->name, optpat, length)) /* match found */
    {
      (*opt_res)= opt;
      if (!count)
	*ffname= (char *) opt->name;     /* we only need to know one prev */
      if (length == strlen(opt->name))   /* exact match */
	return 1;
      count++;
    }
  }
  return count;
}


/* 
  function: compare_strings

  Works like strncmp, other than 1.) considers '-' and '_' the same.
  2.) Returns -1 if strings differ, 0 if they are equal
*/

static my_bool compare_strings(register const char *s, register const char *t,
			       uint length)
{
  char const *end= s + length;
  for (;s != end ; s++, t++)
  {
    if ((*s != '-' ? *s : '_') != (*t != '-' ? *t : '_'))
      return 1;
  }
  return 0;
}

/*
  function: eval_num_suffix

  Transforms a number with a suffix to real number. Suffix can
  be k|K for kilo, m|M for mega or g|G for giga.
*/

static longlong eval_num_suffix (char *argument, int *error, char *option_name)
{
  char *endchar;
  longlong num;
  
  *error= 0;
  num= strtoll(argument, &endchar, 10);
  if (*endchar == 'k' || *endchar == 'K')
    num*= 1024L;
  else if (*endchar == 'm' || *endchar == 'M')
    num*= 1024L * 1024L;
  else if (*endchar == 'g' || *endchar == 'G')
    num*= 1024L * 1024L * 1024L;
  else if (*endchar)
  {
    fprintf(stderr,
	    "Unknown suffix '%c' used for variable '%s' (value '%s')\n",
	    *endchar, option_name, argument);
    *error= 1;
    return 0;
  }
  return num;
}

/* 
  function: getopt_ll

  Evaluates and returns the value that user gave as an argument
  to a variable. Recognizes (case insensitive) K as KILO, M as MEGA
  and G as GIGA bytes. Some values must be in certain blocks, as
  defined in the given my_option struct, this function will check
  that those values are honored.
  In case of an error, set error value in *err.
*/

static longlong getopt_ll (char *arg, const struct my_option *optp, int *err)
{
  longlong num;
  
  num= eval_num_suffix(arg, err, (char*) optp->name);
  if (num < (longlong) optp->min_value)
    num= (longlong) optp->min_value;
  else if (num > 0 && (ulonglong) num > (ulonglong) (ulong) optp->max_value
	   && optp->max_value) // if max value is not set -> no upper limit
    num= (longlong) (ulong) optp->max_value;
  num= ((num - (longlong) optp->sub_size) / (optp->block_size ?
					     (ulonglong) optp->block_size :
					     1L));
  return (longlong) (num * (optp->block_size ? (ulonglong) optp->block_size :
			    1L));
}

/*
  function: getopt_ull

  This is the same as getopt_ll, but is meant for unsigned long long
  values.
*/

static ulonglong getopt_ull (char *arg, const struct my_option *optp, int *err)
{
  ulonglong num;

  num= eval_num_suffix(arg, err, (char*) optp->name);  
  if (num < (ulonglong) optp->min_value)
    num= (ulonglong) optp->min_value;
  else if (num > 0 && (ulonglong) num > (ulonglong) (ulong) optp->max_value
	   && optp->max_value) // if max value is not set -> no upper limit
    num= (ulonglong) (ulong) optp->max_value;
  num= ((num - (ulonglong) optp->sub_size) / (optp->block_size ?
					      (ulonglong) optp->block_size :
					      1L));
  return (ulonglong) (num * (optp->block_size ? (ulonglong) optp->block_size :
			     1L));
}

/* 
  function: init_variables

  initialize all variables to their default values
*/

static void init_variables(const struct my_option *options)
{
  for (; options->name; options++)
  {
    if (options->value)
    {
      switch (options->var_type) {
      case GET_BOOL:
	*((my_bool*) options->u_max_value)= *((my_bool*) options->value)=
	  (my_bool) options->def_value;
	break;
      case GET_INT:
	*((int*) options->u_max_value)= *((int*) options->value)=
	  (int) options->def_value;
	break;
      case GET_UINT:
	*((uint*) options->u_max_value)= *((uint*) options->value)=
	  (uint) options->def_value;
	break;
      case GET_LONG:
	*((long*) options->u_max_value)= *((long*) options->value)=
	  (long) options->def_value;
	break;
      case GET_ULONG:
	*((ulong*) options->u_max_value)= *((ulong*) options->value)=
	  (ulong) options->def_value;
	break;
      case GET_LL:
	*((longlong*) options->u_max_value)= *((longlong*) options->value)=
	  (longlong) options->def_value;
	break;
      case GET_ULL:
	*((ulonglong*) options->u_max_value)= *((ulonglong*) options->value)=
	  (ulonglong) options->def_value;
	break;
      default: /* dummy default to avoid compiler warnings */
	break;
      }
    }
  }
}


/*
  function: my_print_options

  Print help for all options and variables.
*/

void my_print_help(const struct my_option *options)
{
  uint col, name_space= 22, comment_space= 57;
  const char *line_end;
  const struct my_option *optp;

  for (optp= options; optp->id; optp++)
  {
    if (optp->id < 256)
    {
      printf("  -%c, ", optp->id);
      col= 6;
    }
    else
    {
      printf("  ");
      col= 2;
    }
    printf("--%s", optp->name);
    col+= 2 + strlen(optp->name);
    if (optp->var_type == GET_STR || optp->var_type == GET_STR_ALLOC)
    {
      printf("%s=name%s ", optp->arg_type == OPT_ARG ? "[" : "",
	     optp->arg_type == OPT_ARG ? "]" : "");
      col+= (optp->arg_type == OPT_ARG) ? 8 : 6;
    }
    else if (optp->var_type == GET_NO_ARG || optp->var_type == GET_BOOL)
    {
      putchar(' ');
      col++;
    }
    else
    {
      printf("%s=#%s ", optp->arg_type == OPT_ARG ? "[" : "",
	     optp->arg_type == OPT_ARG ? "]" : "");
      col+= (optp->arg_type == OPT_ARG) ? 5 : 3;
    }
    if (col > name_space && optp->comment && *optp->comment)
    {
      putchar('\n');
      col= 0;
    }
    for (; col < name_space; col++)
      putchar(' ');
    if (optp->comment && *optp->comment)
    {
      const char *comment= optp->comment, *end= strend(comment);

      while ((uint) (end - comment) > comment_space)
      {
	for (line_end= comment + comment_space; *line_end != ' '; line_end--);
	for (; comment != line_end; comment++)
	  putchar(*comment);
	comment++; // skip the space, as a newline will take it's place now
	putchar('\n');
	for (col= 0; col < name_space; col++)
	  putchar(' ');
      }
      printf("%s", comment);
    }
    putchar('\n');
  }
}


/*
  function: my_print_options

  Print variables.
*/

void my_print_variables(const struct my_option *options)
{
  uint name_space= 34, length;
  char buff[255];
  const struct my_option *optp;

  printf("\nVariables (--variable-name=value)\n");
  printf("and boolean options {FALSE|TRUE}  Value (after reading options)\n");
  printf("--------------------------------- -----------------------------\n");
  for (optp= options; optp->id; optp++)
  {
    if (optp->value)
    {
      printf("%s", optp->name);
      length= strlen(optp->name);
      for (; length < name_space; length++)
	putchar(' ');
      switch (optp->var_type) {
      case GET_STR:
      case GET_STR_ALLOC:                    /* fall through */
	printf("%s\n", *((char**) optp->value) ? *((char**) optp->value) :
	       "(No default value)");
	break;
      case GET_BOOL:
	printf("%s\n", *((my_bool*) optp->value) ? "TRUE" : "FALSE");
	break;
      case GET_INT:
	printf("%d\n", *((int*) optp->value));
	break;
      case GET_UINT:
	printf("%d\n", *((uint*) optp->value));
	break;
      case GET_LONG:
	printf("%lu\n", *((long*) optp->value));
	break;
      case GET_ULONG:
	printf("%lu\n", *((ulong*) optp->value));
	break;
      case GET_LL:
	printf("%s\n", llstr(*((longlong*) optp->value), buff));
	break;
      case GET_ULL:
	longlong2str(*((ulonglong*) optp->value), buff, 10);
	printf("%s\n", buff);
	break;
      default: /* dummy default to avoid compiler warnings */
	break;
      }
    }
  }
}