/*
 *  params.c:		Parameter file and command line parsing
 *
 *  Written by:		Stefan Frank
 *			Ullrich Hafner
 *		
 *  This file is part of FIASCO («F»ractal «I»mage «A»nd «S»equence «CO»dec)
 *  Copyright (C) 1994-2000 Ullrich Hafner <hafner@bigfoot.de>
 */

/*
 *  $Date: 2000/07/15 17:24:21 $
 *  $Author: hafner $
 *  $Revision: 5.2 $
 *  $State: Exp $
 */

#define _BSD_SOURCE 1   /* Make sure strdup() is in string.h */
#define _XOPEN_SOURCE 500  /* Make sure strdup() is in string.h */

#include "config.h"

#include <stdio.h>
#include <ctype.h>
#include <math.h>			/* strtod() on SUN sparc */

#include <stdlib.h>
#include <string.h>
 
#include <getopt.h>			/* system or ../lib */

#include "nstring.h"

#include "types.h"
#include "macros.h"
#include "bit-io.h"
#include "misc.h"
#include "fiasco.h"

#include "binerror.h"

#include "params.h"

/*****************************************************************************

				prototypes
  
*****************************************************************************/

static void
read_parameter_file (param_t *params, FILE *file);
static int
get_parameter_index (const param_t *params, const char *search_string);
static void
set_parameter (param_t *parameter, const char *value);
static void 
usage (const param_t *params, const char *progname, const char *synopsis,
       const char *comment, const char *non_opt_string,
       bool_t show_all_options, const char *sys_file_name,
       const char *usr_file_name);

/*****************************************************************************

				public code
  
*****************************************************************************/

int
parseargs (param_t *usr_params, 
           int argc, char **argv, 
           const char *synopsis,
           const char *comment, 
           const char *non_opt_string, 
           const char *path,
           const char *sys_file_name, 
           const char *usr_file_name)
/*
 *  Perform the command line parsing.
 *  List of allowed parameters is given by 'usr_params'.
 *  Command line and number of parameters are given by 'argv' and 'argc'.
 *  'synopsis' contains a brief description of the program and
 *  'comment' may contain some additional advice.
 *  Initialization order of parameters:
 *	1.) Default values given by the param_t struct
 *	2.) System parameter-file ('path'/'sys_file_name')
 *	3.) User parameter-file ($HOME/'usr_file_name')
 *	4.) Command line parameters
 *	5.) Parameter-file forced by option -f (--config-file)
 *
 *  Return value:
 *	index in ARGV of the first ARGV-element that is not an option.
 *
 *  Side effects:
 *	the elements of ARGV are permuted
 *      usr_params [].value is modified 
 */
{
   extern int optind;			/* index in ARGV of the 1st element
					   that is not an option */
   bool_t     detailed_help = NO;	/* NO if all parameters can be modified
					   with short options too */
   unsigned   n1;			/* number of user parameters */
   unsigned   n2;			/* number of system parameters */
   bool_t     read_config_file = NO;	/* will override command line */
   param_t    *params;			/* array of user and system params */
   param_t    *sys_params;		/* array of system parameters */
   param_t    detailed_sys_params [] =  /* detailed system parameters */
   {
      {"version", NULL, 'v', PFLAG, {0}, NULL,
       "Print program version number, then exit."},
      {"verbose", "NUM", 'V', PINT, {0}, "1",
       "Set level of verbosity to `%s'."},
      {"config", "FILE", 'f', PSTR, {0}, NULL,
       "Load `%s' to initialize parameters."},
      {"info", NULL, 'h', PFLAG, {0}, NULL,
       "Print brief help, then exit."},
      {"help", NULL, 'H', PFLAG, {0}, NULL,
       "Print detailed help, then exit."},
      {NULL, NULL, 0, PSTR, {0}, NULL, NULL }
   };
   param_t    short_sys_params [] =	/* short system parameters */
   {
      {"version", NULL, 'v', PFLAG, {0}, NULL,
       "Print program version number, then exit."},
      {"verbose", "NUM", 'V', PINT, {0}, "1",
       "Set level of verbosity to `%s'."},
      {"config", "FILE", 'f', PSTR, {0}, NULL,
       "Load `%s' to initialize parameters."},
      {"help", NULL, 'h', PFLAG, {0}, NULL,
       "Print this help, then exit."},
      {NULL, NULL, 0, PSTR, {0}, NULL, NULL }
   };
   char *sys_path;			/* path to system config file */

   sys_path = calloc (strlen (path) + strlen (sys_file_name) + 2,
		      sizeof (char));
   if (!sys_path)
      error ("Out of memory.");
   sprintf (sys_path, "%s/%s", path, sys_file_name);

   /*
    *  Set parameters defaults
    */
   {
       param_t *p;
      
       for (p = usr_params; p->name != NULL; p++)
       {
           set_parameter (p, p->default_value);
           if (p->optchar == '\0')
               detailed_help = YES;
       }

      sys_params = detailed_help ? detailed_sys_params : short_sys_params;
      
      for (p = sys_params; p->name != NULL; p++)
          set_parameter (p, p->default_value);
   }
   /*
    *  Append system command line option to user parameters
    */
   for (n1 = 0; usr_params [n1].name != NULL; n1++)
      ;
   for (n2 = 0; sys_params [n2].name != NULL; n2++)
      ;
   params = calloc (n1 + n2 + 1, sizeof (param_t));
   if (!params)
      error ("Out of memory.");

   memcpy (params, usr_params, n1 * sizeof (param_t));
   memcpy (params + n1, sys_params, (n2 + 1) * sizeof (param_t));
   /*
    *  Try to open the system resource file 'path'/'sys_file_name'
    */
   {
      FILE *parameter_file = open_file (sys_path, NULL, READ_ACCESS);
      if (parameter_file == NULL)
/*
	 warning ("No system resource file found.");
*/ {}
      else
      {
	 read_parameter_file (params, parameter_file);
	 fclose (parameter_file);
      }
   }
   /*
    *  Try to read user resource file $HOME/'usr_file_name'
    */
   {
      FILE *parameter_file = open_file (usr_file_name, "HOME", READ_ACCESS);
      if (parameter_file != NULL)
      {
	 read_parameter_file (params, parameter_file);
	 fclose (parameter_file);
      }
   }
   /*
    *  Parse command line options
    */
   {
      extern char   *optarg;		/* argument of current option */
      struct option *long_options;	/* array of long options */
      int	     option_index = 0;
      char	     optstr [MAXSTRLEN]; /* string containing the legitimate
					    option characters */
      int	     optchar;		/* found option character */

      /*
       *  Build short option string for getopt_long (). 
       */
      {
	 param_t *p;			/* counter */
	 char	 *ptr_optstr;		/* pointer to position in string */
	 
	 ptr_optstr = optstr;
	 for (p = params; p->name != NULL; p++)
	    if (p->optchar != '\0')
	    {
	       *ptr_optstr++ = p->optchar;
	       if (p->type == POSTR)
	       {
		  *ptr_optstr++ = ':';
		  *ptr_optstr++ = ':';
	       }
	       else if (p->type != PFLAG)
		  *ptr_optstr++ = ':';
	    }
	 *ptr_optstr = '\0';
      }
      
      /*
       *  Build long option string for getopt_long (). 
       */
      {
	 int i;
	 
	 long_options = calloc (n1 + n2 + 1, sizeof (struct option));
	 if (!long_options)
	    error ("Out of memory.");
	 for (i = 0; params [i].name != NULL; i++)
	 {
	    long_options [i].name    = params [i].name;
	    switch (params [i].type)
	    {
	       case PFLAG:
		  long_options [i].has_arg = 0;
		  break;
	       case POSTR:
		  long_options [i].has_arg = 2;
		  break;
	       case PINT:
	       case PSTR:
	       case PFLOAT:
	       default:
		  long_options [i].has_arg = 1;
		  break;
	    }
	    long_options [i].has_arg = params [i].type != PFLAG;
	    long_options [i].flag    = NULL;
	    long_options [i].val     = 0;
	 }
      }
      
      /*
       *  Parse comand line
       */
      while ((optchar = getopt_long (argc, argv, optstr, long_options,
				     &option_index)) != EOF)
      {
	 int param_index = -1;
	 
	 switch (optchar)
	 {
	    case 0:
	       param_index = option_index;
	       break;
	    case ':':
	       if (detailed_help)
		  fprintf (stderr,
			   "Try `%s -h' or `%s --help' for "
			   "more information.\n",
			   argv [0], argv [0]);
	       else
		  fprintf (stderr, "Try `%s --help' for more information.\n",
			   argv [0]);
	       exit (2);
	       break;
	    case '?':
	       if (detailed_help)
		  fprintf (stderr,
			   "Try `%s -h' or `%s --help' "
			   "for more information.\n",
			   argv [0], argv [0]);
	       else
		  fprintf (stderr, "Try `%s --help' for more information.\n",
			   argv [0]);
	       exit (2);
	       break;
	    default:
	       {
		  int i;
		  
		  for (i = 0; params [i].name != NULL; i++)
		     if (params [i].optchar == optchar)
		     {
			param_index = i;
			break;
		     }
	       }
	 }
	 /*
	  *  Check for system options
	  */
	 if (param_index >= 0)
	 {
	    set_parameter (params + param_index, optarg ? optarg : "");
	    if (streq (params [param_index].name, "help"))
	       usage (params, argv [0], synopsis, comment, non_opt_string,
		      YES, sys_path, usr_file_name);
	    else if (streq (params [param_index].name, "info"))
	       usage (params, argv [0], synopsis, comment, non_opt_string,
		      NO, sys_path, usr_file_name);
	    else if (streq (params [param_index].name, "version"))
	    {
	       fprintf (stderr, "%s " VERSION "\n", argv [0]);
	       exit (2);
	    }
	    else if (streq (params [param_index].name, "verbose"))
	       fiasco_set_verbosity (
               * (fiasco_verbosity_e *) parameter_value (params,
                                                         "verbose"));
	    else if (streq (params [param_index].name, "config"))
	       read_config_file = YES;
	    param_index = -1;		/* clear index flag */
	 }
      }

      free (long_options);
   }
   
   /*
    *  Read config-file if specified by option -f
    */
   if (read_config_file)
   {
      char *filename;

      if ((filename = (char *) parameter_value (params, "config")) != NULL)
      {
	 FILE *parameter_file;		/* input file */
	 
	 warning ("Options set in file `%s' will override"
		  " command line options.", filename);
	 parameter_file = open_file (filename, NULL, READ_ACCESS);
	 if (parameter_file != NULL)
	 {
	    read_parameter_file (params, parameter_file);
	    fclose (parameter_file);
	 }
	 else
	    file_error (filename);
      }
      else
	 error ("Invalid config filename.");
   }

   memcpy (usr_params, params, n1 * sizeof (param_t)); /* fill user struct */
   free (sys_path);
   
   return optind;
}
 
void *
parameter_value (const param_t *params, const char *name)
/*
 *  Extract value of parameter 'name.' of the given parameters 'params'.
 *
 *  Return value:
 *	value of given parameter
 */
{
   int pind = get_parameter_index (params, name);

   if (pind < 0)
      error ("Invalid parameter `%s'.", name);

   if (params [pind].type == PSTR || params [pind].type == POSTR)
      return (void *) params [pind].value.s;
      
   return (void *) &(params [pind].value);
}

void
ask_and_set (param_t *params, const char *name, const char *msg)
/*
 *  Ask user (print given message 'msg') for missing mandatory
 *  parameter 'name' of the given parameters 'params'.
 *
 *  No return value.
 *
 *  Side effects:
 *	'params ['name'].value' is changed
 */
{ 
   char answer [MAXSTRLEN];
   int  index = get_parameter_index (params, name);

   if (index < 0)
      error ("Invalid parameter %s.", name);

   if (msg)
      fprintf (stderr, "%s\n", msg);
  
   switch (params [index].type)
   {
      case PFLAG:			/* Unusual, at least. */
	 warning ("Flags should be initialized and set on demand, "
		  "not request");
      case PINT:
      case PSTR:
      case POSTR:
      case PFLOAT:
	 scanf (MAXSTRLEN_SCANF, answer);
	 set_parameter (&params [index], answer);
	 break;
      default:
	 error ("Invalid parameter type for %s", name);
   }
} 

void
write_parameters (const param_t *params, FILE *output)
/*
 *  Write all parameter settings to 'output'.
 *
 *  No return value.
 */
{
   int pind;

   if (!params || !output)
      error ("Parameters must be not NULL.");

   for (pind = 0; params [pind].name != NULL; pind++)
   {
      fprintf (output, "# %s = ", params [pind].name);
      switch (params [pind].type)
      {
	 case PFLAG:
	    fprintf (output, "%s\n", params [pind].value.b ? "TRUE" : "FALSE");
	    break;
	 case PINT:
	    fprintf (output, "%d\n", params [pind].value.i);
	    break;
	 case PFLOAT:
	    fprintf (output, "%.4f\n", (double) params [pind].value.f);
	    break;
	 case PSTR:
	 case POSTR:
	    fprintf (output, "%s\n", params [pind].value.s);
	    break;
	 default:
	    error ("Invalid type %d for parameter %s",
		   params [pind].type, params [pind].name);
      }
   }
   fputc ('\n', output);
}

/*****************************************************************************

				private code
  
*****************************************************************************/

static void
set_parameter (param_t *parameter, const char *value)
/*
 *  Set value of 'parameter' to 'value'.
 *
 *  No return value.
 *
 *  Side effects:
 *	'parameter.value' is changed accordingly
 */
{
   assert (parameter);
   
   switch (parameter->type)
   {
      case PFLAG:
	 if (value != NULL && *value != '\0')
	 {
	    if (strcaseeq (value, "TRUE"))
	       parameter->value.b = YES;
	    else if (strcaseeq (value, "FALSE"))
	       parameter->value.b = NO;
	    else if (strcaseeq (value, "YES"))
	       parameter->value.b = YES;
	    else if (strcaseeq (value, "NO"))
	       parameter->value.b = NO;
	    else
	    {
	       long int	data;
	       char	*endptr;
	    
	       data = strtol (value, &endptr, 0);
	       if (*endptr != '\0' || endptr == value)
		  warning ("Invalid value `%s' converted to %d",
			   value, (int) data);
	       parameter->value.b = data ? YES : NO;
	    }
	 }
	 else
	    parameter->value.b = !parameter->value.b;
	 break;
      case PINT:
	 {
	    long int  data;
	    char     *endptr;
	    
	    data = strtol (value, &endptr, 0);
	    if (*endptr != '\0' || endptr == value)
	       warning ("Invalid value `%s' converted to %d",
			value, (int) data);
	    parameter->value.i = data;
	 }
	 break;
      case PFLOAT:
	 {
	    double	data;
	    char	*endptr;
	    
	    data = strtod (value, &endptr);
	    if (*endptr != '\0' || endptr == value)
	       warning ("Invalid value `%s' converted to %f",
			value, (double) data);
	    parameter->value.f = data;
	 }
	 break;
      case PSTR:
      case POSTR:
	 parameter->value.s = value ? strdup (value) : NULL;
	 break;
      default:				
	 error ("Invalid parameter type for %s", parameter->name);
   }
}

static int
get_parameter_index (const param_t *params, const char *search_string)
/*
 *  Search for parameter with name 'search_string' in parameter struct.
 *
 *  Return value:
 *	index of parameter or -1 if no matching parameter has been found
 */
{
   int n;
   int index = -1;

   assert (params && search_string);

   for (n = 0; params [n].name != NULL; n++)
      if (strcaseeq (params [n].name, search_string))
      {
	 index = n;
	 break;
      }

   return index;
}

static void
read_parameter_file (param_t *params, FILE *file)
/*
 *  Read parameter settings from 'file'.
 *
 *  No return value.
 *
 *  Side effects:
 *	'params [].value' are changed if specified in 'file'
 */
{
   char buffer [MAXSTRLEN];
   int  n = 0;

   assert (params && file);

   while (fgets (buffer, MAXSTRLEN, file) != NULL)
   {
      char *b;				/* temporary variable */
      char *name;			/* parameter name */
      char *value;			/* parameter value */
      int   pind;			/* current argument number */
      
      b = strchr (buffer, '#');
      if (b != NULL)			/* Strip comments. */
	 *b = '\0';

      b = strchr (buffer, '=');
      if (b == NULL)			/* Strip lines that contain no '=' */
	 continue;
      *b = '\0';			/* Replace '=' by string terminator */

      /*
       *  Extract value of parameter
       */
      for (value = b + 1; ISSPACE (*value); value++) 
	 ;				/* Delete leading spaces */

      for (b = value + strlen (value) - 1; b >= value && ISSPACE (*b); b--)
	 *b = '\0';			/* Delete trailing spaces. */

      /*
       *  Extract parameter name
       */
      for (name = buffer; ISSPACE (*name); name++) 
	 ;				/* Delete leading spaces */

      for (b = name + strlen (name) - 1; b >= name && ISSPACE (*b); b--)
	 *b = '\0';			/* Delete trailing spaces. */

      pind = get_parameter_index (params, name);
      if (pind >= 0)
	 set_parameter (&params [pind], value);
      
      n++;
   }
}   

static void 
usage (const param_t *params, const char *progname, const char *synopsis,
       const char *comment, const char *non_opt_string,
       bool_t show_all_options, const char *sys_file_name,
       const char *usr_file_name)
/*
 *  Generates and prints command line description from param_t struct 'params'.
 *  'progname' is the name of the excecutable, 'synopsis' a short program
 *  description, and 'comment' some more advice.
 *  If flag 'show_all_options' is set then print also options that are not
 *  associated with a short option character.
 *  'sys_file_name' and 'usr_file_name' are filenames to parameter files.
 *
 *  No return value.
 */
{
   int	  i;
   size_t width = 0;
   
   fprintf (stderr, "Usage: %s [OPTION]...%s\n", progname,
	    non_opt_string ? non_opt_string : " ");
   if (synopsis != NULL)
      fprintf (stderr, synopsis);
   fprintf (stderr, "\n\n");
   fprintf (stderr, "Mandatory or optional arguments to long options "
	    "are mandatory or optional\nfor short options too. "
	    "Default values are surrounded by {}.\n");
   for (i = 0; params [i].name != NULL; i++)
      if (params [i].optchar != '\0' || show_all_options)
      {
	 if (params [i].type == POSTR)
	    width = max (width, (strlen (params [i].name)
				 + strlen (params [i].argument_name) + 2));
	 else if (params [i].type != PFLAG)
	    width = max (width, (strlen (params [i].name)
				 + strlen (params [i].argument_name)));
	 else
	    width = max (width, (strlen (params [i].name)) - 1);
      }
   
   for (i = 0; params [i].name != NULL; i++)
      if (params [i].optchar != '\0' || show_all_options)
      {
	 if (params [i].optchar != '\0')
	    fprintf (stderr, "  -%c, --", params [i].optchar);
	 else
	    fprintf (stderr, "      --");
	 
	 if (params [i].type == POSTR)
	    fprintf (stderr, "%s=[%s]%-*s  ", params [i].name,
		     params [i].argument_name,
		     max (0, (width - 2 - strlen (params [i].name)
			   - strlen (params [i].argument_name))), "");
	 else if (params [i].type != PFLAG)
	    fprintf (stderr, "%s=%-*s  ", params [i].name,
		  width - strlen (params [i].name),
		  params [i].argument_name);
	 else
	    fprintf (stderr, "%-*s  ", width + 1, params [i].name);

	 fprintf (stderr, params [i].use, params [i].argument_name);
	 
	 switch (params [i].type)
	 {
	    case PFLAG:
	       break;
	    case PINT:
	       fprintf (stderr, "{%d}", params [i].value.i);
	       break;
	    case PFLOAT:
	       fprintf (stderr, "{%.2f}", (double) params [i].value.f);
	       break;
	    case PSTR:
	    case POSTR:
	       if (params [i].value.s)
		  fprintf (stderr, "{%s}", params [i].value.s);
	       break;
	    default:
	       error ("type %d for %s invalid",
		      params [i].type, params [i].name);
	 }
	 fprintf (stderr, "\n");
      }
   fprintf (stderr, "\n");
   fprintf (stderr, "Parameter initialization order:\n");
   fprintf (stderr,
	    "1.) %s\n2.) $HOME/%s\t 3.) command line\t 4.) --config=file",
	    sys_file_name, usr_file_name);
   fprintf (stderr, "\n\n");
   if (comment != NULL)
      fprintf (stderr, "%s\n", comment);

   exit (1);
}

