eliot/dic/dic_search.c

/* Eliot                                                                     */
/* Copyright (C) 1999  Antoine Fraboulet                                     */
/*                                                                           */
/* This file is part of Eliot.                                               */
/*                                                                           */
/* Eliot 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.                                       */
/*                                                                           */
/* Elit 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */

/**
 *  \file   dic_search.c
 *  \brief  Dictionary lookup functions
 *  \author Antoine Fraboulet
 *  \date   2002
 */

#include <ctype.h>
#include <stdlib.h>
#include <string.h>

#include "dic_internals.h"
#include "dic.h"
#include "regexp.h"
#include "dic_search.h"
#include "libdic_a-er.h" /* generated by bison */
#include "scanner.h"     /* generated by flex  */
#include "automaton.h"

/*
 * shut down the compiler
 */
static int yy_init_globals (yyscan_t yyscanner )
{
  yy_init_globals(yyscanner);
  return 0;
}

/**
 * Dic_seel_edgeptr
 * walk the dictionary until the end of the word
 * @param dic : dictionnary
 * @param s : current pointer to letters
 * @param eptr : current edge in the dawg
 */
static Dawg_edge*
Dic_seek_edgeptr(const Dictionary dic, const char* s, Dawg_edge *eptr)
{
  if (*s)
    {
      Dawg_edge *p = dic->dawg + eptr->ptr;
      do {
        if (p->chr == (unsigned)(*s & DIC_CHAR_MASK))
          return Dic_seek_edgeptr (dic,s + 1, p);
      } while (!(*p++).last);
      return dic->dawg;
    }
  else
    return eptr;
}


/**
 * Dic_search_word : direct application of Dic_seek_edgeptr
 * @param dic : dictionary
 * @param word : word to lookup
 * @result 0 not a valid word, 1 ok
 */

int
Dic_search_word(const Dictionary dic, const char* word)
{
  Dawg_edge *e;
  e = Dic_seek_edgeptr(dic,word,dic->dawg + dic->root);
  return e->term;
}


/**
 * global variables for Dic_search_word_by_len :
 *
 * a pointer to the structure is passed as a parameter
 * so that all the search_* variables appear to the functions
 * as global but the code remains re-entrant.
 * Should be better to change the algorithm ...
 */

struct params_7plus1_t {
 Dictionary search_dic;
 int search_len;
 int search_wordlistlen;
 int search_wordlistlenmax;
 char search_wordtst[DIC_WORD_MAX];
 char search_letters[DIC_LETTERS];
 char (*search_wordlist)[RES_7PL1_MAX][DIC_WORD_MAX];
};

static void
Dic_search_word_by_len(struct params_7plus1_t *params, int i, Dawg_edge *edgeptr)
{
  /* depth first search in the dictionary */
  do {
    /* we use a static array and not a real list so we have to stop if
     * the array is full */
    if (params->search_wordlistlen >= params->search_wordlistlenmax)
      break;

    /* the test is false only when reach the end-node */
    if (edgeptr->chr)
      {

	/* is the letter available in search_letters */
	if (params->search_letters[edgeptr->chr])
	  {
	    params->search_wordtst[i] = edgeptr->chr + 'A' - 1;
	    params->search_letters[edgeptr->chr] --;
	    if (i == params->search_len)
	      {
		if ((edgeptr->term)
		  /* && (params->search_wordlistlen < params->search_wordlistlenmax) */)
		  strcpy((*params->search_wordlist)[params->search_wordlistlen++],params->search_wordtst);
	      }
	    else /* if (params->search_wordlistlen < params->search_wordlistlenmax) */
	      {
		Dic_search_word_by_len(params,i + 1, params->search_dic->dawg + edgeptr->ptr);
	      }
	    params->search_letters[edgeptr->chr] ++;
	    params->search_wordtst[i] = '\0';
	  }

	/* the letter is of course available if we have a joker available */
	if (params->search_letters[0])
	  {
	    params->search_wordtst[i] = edgeptr->chr + 'a' - 1;
	    params->search_letters[0] --;
	    if (i == params->search_len)
	      {
		if ((edgeptr->term)
		     /* && (params->search_wordlistlen < params->search_wordlistlenmax) */)
		  strcpy((*(params->search_wordlist))[params->search_wordlistlen++],params->search_wordtst);
	      }
	    else /* if (params->search_wordlistlen < params->search_wordlistlenmax) */
	      {
		Dic_search_word_by_len(params,i + 1,params->search_dic->dawg + edgeptr->ptr);
	      }
	    params->search_letters[0] ++;
	    params->search_wordtst[i] = '\0';
	  }
      }
  } while (! (*edgeptr++).last);
}

void
Dic_search_7pl1(const Dictionary dic, const char* rack,
                char buff[DIC_LETTERS][RES_7PL1_MAX][DIC_WORD_MAX],
                int joker)
{
  int i,j,wordlen;
  const char* r = rack;
  struct params_7plus1_t params;
  Dawg_edge *root_edge;

  for(i=0; i < DIC_LETTERS; i++)
    for(j=0; j < RES_7PL1_MAX; j++)
      buff[i][j][0] = '\0';

  for(i=0; i<DIC_LETTERS; i++)
    params.search_letters[i] = 0;

  if (dic == NULL || rack == NULL)
    return;

  /*
   * the letters are verified and changed to the dic internal
   * representation (*r & DIC_CHAR_MASK)
   */
  for(wordlen=0; wordlen < DIC_WORD_MAX && *r; r++)
    {
      if (isalpha(*r))
	{
	  params.search_letters[(int)*r & DIC_CHAR_MASK]++;
          wordlen++;
	}
      else if (*r == '?')
	{
	  if (joker)
	    {
	      params.search_letters[0]++;
	      wordlen++;
	    }
	  else
	    {
	      strncpy(buff[0][0],"** joker **",DIC_WORD_MAX);
	      return;
	    }
	}
    }

  if (wordlen < 1)
    return;

  root_edge = dic->dawg + (dic->dawg[dic->root].ptr);

  params.search_dic = dic;
  params.search_wordlistlenmax = RES_7PL1_MAX;

  /* search for all the words that can be done with the letters */
  params.search_len = wordlen - 1;
  params.search_wordtst[wordlen]='\0';
  params.search_wordlist = & buff[0];
  params.search_wordlistlen = 0;
  Dic_search_word_by_len(&params,0,root_edge);

  /* search for all the words that can be done with the letters +1 */
  params.search_len = wordlen;
  params.search_wordtst[wordlen + 1]='\0';
  for(i='a'; i <= 'z'; i++)
    {
      params.search_letters[i & DIC_CHAR_MASK]++;

      params.search_wordlist = & buff[i & DIC_CHAR_MASK];
      params.search_wordlistlen = 0;
      Dic_search_word_by_len(&params,0,root_edge);

      params.search_letters[i & DIC_CHAR_MASK]--;
    }
}

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

void
Dic_search_Racc(const Dictionary dic, const char* word,
                char wordlist[RES_RACC_MAX][DIC_WORD_MAX])
{
  /* search_racc will try to add a letter in front and at the end of a word */

  int i,wordlistlen;
  Dawg_edge *edge;
  char wordtst[DIC_WORD_MAX];

  for(i=0; i < RES_RACC_MAX; i++)
    wordlist[i][0] = 0;

  if (dic == NULL || wordlist == NULL)
    return;

  /* let's try for the front */
  wordlistlen = 0;
  strcpy(wordtst+1,word);
  for(i='a'; i <= 'z'; i++)
    {
      wordtst[0] = i;
      if (Dic_search_word(dic,wordtst) && wordlistlen < RES_RACC_MAX)
	strcpy(wordlist[wordlistlen++],wordtst);
    }

  /* add a letter at the end */
  for(i=0; word[i]; i++)
    wordtst[i] = word[i];

  wordtst[i  ] = '\0';
  wordtst[i+1] = '\0';

  edge = Dic_seek_edgeptr(dic,word,dic->dawg + dic->root);

  /* points to what the next letter can be */
  edge = dic->dawg + edge->ptr;

  if (edge != dic->dawg)
    {
      do {
	  if (edge->term && wordlistlen < RES_RACC_MAX)
	    {
	      wordtst[i] = edge->chr + 'a' - 1;
	      strcpy(wordlist[wordlistlen++],wordtst);
	    }
      } while (!(*edge++).last);
    }
}

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


void
Dic_search_Benj(const Dictionary dic, const char* word,
                char wordlist[RES_BENJ_MAX][DIC_WORD_MAX])
{
  int i,wordlistlen;
  char wordtst[DIC_WORD_MAX];
  Dawg_edge *edge0,*edge1,*edge2,*edgetst;

  for(i=0; i < RES_BENJ_MAX; i++)
    wordlist[i][0] = 0;

  if (dic == NULL || word == NULL)
    return;

  wordlistlen = 0;

  strcpy(wordtst+3,word);
  edge0 = dic->dawg + (dic->dawg[dic->root].ptr);
  do {
    wordtst[0] = edge0->chr + 'a' - 1;
    edge1 = dic->dawg + edge0->ptr;
    do {
      wordtst[1] = edge1->chr + 'a' - 1;
      edge2  = dic->dawg + edge1->ptr;
      do {
	wordtst[2] = edge2->chr + 'a' - 1;
	edgetst = Dic_seek_edgeptr(dic,word,edge2);
	if (edgetst->term && wordlistlen < RES_BENJ_MAX)
	  strcpy(wordlist[wordlistlen++],wordtst);
      } while (!(*edge2++).last);
    } while (!(*edge1++).last);
  } while (!(*edge0++).last);
}


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

struct params_cross_t {
 Dictionary dic;
 int wordlen;
 int wordlistlen;
 int wordlistlenmax;
 char mask[DIC_WORD_MAX];
};


void
Dic_search_cross_rec(struct params_cross_t *params,
		     char wordlist[RES_CROS_MAX][DIC_WORD_MAX],
		     Dawg_edge *edgeptr)
{
  Dawg_edge *current = params->dic->dawg + edgeptr->ptr;

  if (params->mask[params->wordlen] == '\0' && edgeptr->term)
    {
      if (params->wordlistlen < params->wordlistlenmax)
	strcpy(wordlist[params->wordlistlen++],params->mask);
    }
  else if (params->mask[params->wordlen] == '.')
    {
      do
	{
	  params->mask[params->wordlen] = current->chr + 'a' - 1;
	  params->wordlen ++;
	  Dic_search_cross_rec(params,wordlist,current);
	  params->wordlen --;
	  params->mask[params->wordlen] = '.';
	}
      while (!(*current++).last);
    }
  else
    {
      do
	{
	  if (current->chr == (unsigned int)(params->mask[params->wordlen] & DIC_CHAR_MASK))
	    {
	      params->wordlen ++;
	      Dic_search_cross_rec(params,wordlist,current);
	      params->wordlen --;
	      break;
	    }
	}
      while (!(*current++).last);
    }
}



void
Dic_search_Cros(const Dictionary dic, const char* mask,
                char wordlist[RES_CROS_MAX][DIC_WORD_MAX])
{
  int  i;
  struct params_cross_t params;

  for(i=0; i < RES_CROS_MAX; i++)
    wordlist[i][0] = 0;

  if (dic == NULL || mask == NULL)
    return;

  for(i=0; i < DIC_WORD_MAX && mask[i]; i++)
    {
      if (isalpha(mask[i]))
	params.mask[i] = (mask[i] & DIC_CHAR_MASK) + 'A' - 1;
      else
	params.mask[i] = '.';
    }
  params.mask[i] = '\0';

  params.dic            = dic;
  params.wordlen        = 0;
  params.wordlistlen    = 0;
  params.wordlistlenmax = RES_CROS_MAX;
  Dic_search_cross_rec(&params, wordlist, dic->dawg + dic->root);
}

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

struct params_regexp_t {
  Dictionary dic;
  int minlength;
  int maxlength;
  automaton automaton;
  struct search_RegE_list_t *charlist;
  char word[DIC_WORD_MAX];
  int  wordlen;
  int  wordlistlen;
  int  wordlistlenmax;
};

void
Dic_search_regexp_rec(struct params_regexp_t *params,
		      int state,
		      Dawg_edge *edgeptr,
		      char wordlist[RES_REGE_MAX][DIC_WORD_MAX])
{
  int next_state;
  Dawg_edge *current;
  /* if we have a valid word we store it */
  if (automaton_get_accept(params->automaton,state) && edgeptr->term)
    {
      int l = strlen(params->word);
      if (params->wordlistlen < params->wordlistlenmax &&
	  params->minlength <= l                        &&
	  params->maxlength >= l)
	{
	  strcpy(wordlist[params->wordlistlen++],params->word);
	}
    }
  /* we now drive the search by exploring the dictionary */
  current = params->dic->dawg + edgeptr->ptr;
  do {
    /* the current letter is current->chr */
    next_state = automaton_get_next_state(params->automaton,state,current->chr);
    /* 1 : the letter appears in the automaton as is */
    if (next_state)
      {
	params->word[params->wordlen] = current->chr + 'a' - 1;
	params->wordlen ++;
	Dic_search_regexp_rec(params,next_state,current,wordlist);
	params->wordlen --;
	params->word[params->wordlen] = '\0';
      }
  } while (!(*current++).last);
}


    /**
     * function prototype for parser generated by bison
     */
int  regexpparse(yyscan_t scanner, NODE** root,
		 struct search_RegE_list_t *list,
		 struct regexp_error_report_t *err);

void
Dic_search_RegE(const Dictionary dic, const char* re,
                char wordlist[RES_REGE_MAX][DIC_WORD_MAX],
		struct search_RegE_list_t *list)
{
  int i,p,n,value;
  int ptl[REGEXP_MAX+1];
  int PS [REGEXP_MAX+1];
  NODE* root;
  yyscan_t scanner;
  YY_BUFFER_STATE buf;
  automaton a;
  char stringbuf[250];
  struct params_regexp_t params;
  struct regexp_error_report_t report;

  /* init */
  for(i=0; i < RES_REGE_MAX; i++)
    wordlist[i][0] = 0;

  if (dic == NULL || re == NULL)
    return;

  /* (expr)# */
  sprintf(stringbuf,"(%s)#",re);
  for(i=0; i < REGEXP_MAX; i++)
    {
      PS[i] = 0;
      ptl[i] = 0;
    }

  report.pos1 = 0;
  report.pos2 = 0;
  report.msg[0] = '\0';

  /* parsing */
  regexplex_init( &scanner );
  buf   = regexp_scan_string( stringbuf, scanner );
  root  = NULL;
  value = regexpparse( scanner , &root, list, &report);
  regexp_delete_buffer(buf,scanner);
  regexplex_destroy( scanner );

  if (value)
    {
#ifdef DEBUG_FLEX_IS_BROKEN
      fprintf(stderr,"parser error at pos %d - %d : %s\n",
	      report.pos1, report.pos2, report.msg);
#endif
      regexp_delete_tree(root);
      return ;
    }

  n = 1;
  p = 1;
  regexp_parcours(root, &p, &n, ptl);
  PS [0] = p - 1;
  ptl[0] = p - 1;

  regexp_possuivante(root,PS);

  if ((a = automaton_build(root->PP,ptl,PS,list)) != NULL)
    {
      params.dic            = dic;
      params.minlength      = list->minlength;
      params.maxlength      = list->maxlength;
      params.automaton      = a;
      params.charlist       = list;
      memset(params.word,'\0',sizeof(params.word));
      params.wordlen        = 0;
      params.wordlistlen    = 0;
      params.wordlistlenmax = RES_REGE_MAX;
      Dic_search_regexp_rec(&params, automaton_get_init(a), dic->dawg + dic->root, wordlist);

      automaton_delete(a);
    }
  regexp_delete_tree(root);
}

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