/* l5.c - Don Yang (uguu.org)

   04/17/05
                                                                           */

#include<ctype.h>
#include<stdio.h>
#include<stdlib.h>
#include<time.h>


typedef union
{
   char *w;
   int i;
} Element;

typedef struct
{
   int size, max;
   Element *d;
} List;

List Index[26], AllWords;
char *t;


int SLen(char *d)
{
   int r;
   for(r = 0; *d != '\0'; d++, r++);
   return r;
}

void PutStr(char *d)
{
   printf("%s", d);
}

void Reset(List *l)
{
   l->d = NULL;
   l->size = l->max = 0;
}

void AddToList(List *l, char *d)
{
   Element *tmp, *a, *b;
   int size;

   if( l->d == NULL )
   {
      if( (l->d = (Element*)malloc((l->max = 32) * sizeof(Element))) == NULL )
         return;
   }
   if( l->size + 1 > l->max )
   {
      if( (tmp = (Element*)malloc((l->max * 2) * sizeof(Element))) == NULL )
         return;
      a = tmp;
      b = l->d;
      for(size = l->size; size-- > 0; a++->i = b++->i);
      free(l->d);
      l->d = tmp;
      l->max <<= 1;
   }
   l->d[l->size++].w = d;
}

void FreeList(List *l)
{
   if( l->d != NULL )
      free(l->d);
}

void Tokenize(char *text, int size)
{
   for(t = text; size-- > 0; *(t++) = '\0')
   {
      if( isalpha(*t) )
      {
         *t = tolower(*t);
         AddToList(&Index[*t - 'a'], (char*)AllWords.size);
         AddToList(&AllWords, t);
         for(; size-- > 0 ? isalnum(*t) : 0; t++)
            *t = tolower(*t);
         size++;
      }
   }
}

int PartialMatch(char *a, char *b)
{
   int c;

   for(c = 0; *a != '\0' && *b != '\0' && *a == *b; a++, b++, c++);
   return c;
}


int main(int argc, char **argv)
{
   FILE *infile;
   char *text;
   int size, i, j, k, k0, k1, a, c0, column, margin;

   if( argc < 2 )
      return printf("%s <file> [width] [...]\n", *argv);

   if( (infile = fopen(argv[1], "rb")) == NULL )
      return printf("Can not open %s\n", argv[1]);
   fseek(infile, 0, SEEK_END);
   if( (size = ftell(infile)) < 1 )
   {
      fclose(infile);
      return printf("%s too small\n", argv[1]);
   }
   fseek(infile, 0, SEEK_SET);
   if( (text = (char*)malloc(size + 1)) == NULL )
      return fclose(infile);
   fread(text, size, 1, infile);
   text[size] = '\0';
   fclose(infile);

   for(i = 0; i < 26; Reset(&Index[i++]));
   Reset(&AllWords);
   Tokenize(text, size);

   if( (size = (argc > 2) ? atoi(argv[2]) : 80) < 1 )
      size = 80;

   srand(time(NULL));
   if( argc > 3 )
   {
      for(a = argc; a-- > 3;)
      {
         putchar('\n');
         t = argv[a];
         column = SLen(t);
         for(i = 0; i < column; i++)
            t[i] = tolower(t[i]);
         PutStr(t);

         margin = size - 1 - SLen(argv[a - 1]);

         while( column < margin )
         {
            do
            {
               c0 = *t - 'a';
               do
               {
                  i = rand() % AllWords.size;
                  if( c0 < 0 || c0 >= 26 )    break;
                  if( Index[c0].size == 0 )   break;
                  i = Index[c0].d[rand() % Index[c0].size].i;
                  k0 = PartialMatch(t, AllWords.d[i].w);
                  for(j = 0; j < Index[c0].size / 2; j++)
                  {
                     k = Index[c0].d[rand() % Index[c0].size].i;
                     if( (k1 = PartialMatch(t, AllWords.d[k].w)) > k0 )
                     {
                        i = k;
                        k0 = k1;
                     }
                  }
                  i = (i + 1) % AllWords.size;
               } while(0);

            } while( column + 1 + SLen(AllWords.d[i].w) >= size );

            putchar(' ');
            PutStr(t = AllWords.d[i].w);
            column += 1 + SLen(t);
         }
      }
   }
   else
   {
      column = size;
      for(i = 0; i < AllWords.size; i++)
      {
         if( (column + 1 + SLen(AllWords.d[i].w)) >= size )
         {
            putchar('\n');
            column = 0;
         }
         else
         {
            putchar(' ');
            column++;
         }
         printf(AllWords.d[i].w);
         column += SLen(AllWords.d[i].w);
      }
   }
   PutStr("\n\n");

   for(i = 0; i < 26; FreeList(&Index[i++]));
   FreeList(&AllWords);
   free(text);
   return 0;
}