//Christopher Busch
//(c) 1993 all rights reserved.
//eliza.cpp

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <search.h>
#include <unistd.h>

#include "eliza.hpp"

#ifdef DMALLOC
# include "dmalloc.h"
#endif

eliza::~eliza()
{
}

bool eliza::addname(char* n,int d)  //add one name and number
{
	if(numnames < maxnames)
	{
		for(int i = strlen(n) - 1; i >= 0; i--)
			if(n[i]=='_') n[i]=' ';
//    printf("found person '%s' at %d \n",n,d);
		return thenames[numnames++].set(n,d) != NULL;
	}
	return false;
}

int namecompare(const void* a,const void* b)
{
  return strcasecmp( ((eliza::nametype*)a)->name,
                     ((eliza::nametype*)b)->name );
}

void eliza::sortnames()
{
  qsort((char*)thenames,numnames,sizeof(eliza::nametype),namecompare);
}

int eliza::getname(char* n)
{
	nametype finder;
	if(finder.set(n,0) == NULL)
		return 0;
	nametype* nt = (nametype*) bsearch((char*)&finder,(char*)thenames,numnames,
												  sizeof(nametype),namecompare);
  if( nt == NULL)
		return 0;
	return nt->dbase;
}

void eliza::reducespaces(char *m)
{
	int len = strlen(m), space = m[0] < ' ', count = 0;

	for(int i=0;i<len;i++)
	{
		if(!space || m[i]>' ' )
		{
			m[count]= (m[i]<' ' ? ' ' : m[i]);
			count++;
		}
		space = m[i] < ' ';
	}
	if(count)
		m[count]='\0';
}

int subst(char start[],char sub1[],char sub2[])
{
  int ln1 = strlen(sub1),changed=0;
  char s[MAXSIZE];
  while((start = strstr(start,sub1))!=NULL)
    {
      changed = 1;
      for(int i = 0;i<ln1;i++)
        start[i] = ' ';
      strcpy(s,start);
      sprintf(start,"%s%s",sub2,s);
    }
  return changed;
}

//Gets a word out of a string.
int fggetword(char*& input,char* outword,char& outother) //0 if done
{
	outword[0] = 0;
  char *outword0=outword;
  int curchar;
  curchar=input[0];

  while( isalnum(curchar) || curchar=='_' )
    {
      *outword=curchar;
      outword++;
      input++;
      curchar=*input;
    }
  if(*input!= '\0') input++;
  *outword='\0';
  outother=curchar;
  if( curchar == 0 && outword0[0]==0 ) return 0;
  return 1;
}

//add more then one name to some number
bool eliza::addbunch(char* names,int dbase)
{
	char aword[MAXSIZE+3];
	char otherch;
	char* theinput=names;

	while( fggetword(theinput,aword,otherch) )
	{
		if( addname(aword,dbase) == false )
			return false;
	}
	return true;
}

//This tries more exhaustively to find a name out of the database
//for example if 'Bobby Jo' fails, it will try Bobby then Jo.
int eliza::getanyname(char* n)
{
	int dbase=getname(n);

	if(dbase == 0)
	{
		char aword[MAXSIZE+3];
		char otherch;
		char* theinput = n;

		while( fggetword(theinput,aword,otherch) )
		{
			dbase = getname(aword);
			if(dbase != 0)
				return dbase;
		}
	}
	return dbase;
}

char *substit(char *in)
{
	static const char pairs[][10]=
	{ "am","are",
     "I","you",
     "mine","yours",
     "my","your",
     "me","you",
     "myself","yourself",
     //swapped order:
     "you","I",
     "yours","mine",
     "your","my",
     "yourself","myself",
		"",""
	};

	for(int i=0;pairs[i*2][0]!='\0';i++)
	{
      if(strcasecmp(in,pairs[i*2])==0)
		{
			return (char*)pairs[i*2+1];
		}
   }
	return in;
}

void fixgrammer(char s[])
{
  char newsent[MAXSIZE+20];
  newsent[0]='\0';

  char aword[MAXSIZE+3];
  char* theinput;
  theinput=s;
  char otherch;
  char ministr[]=" ";

  while( fggetword(theinput,aword,otherch))
    {
#ifdef DEBUG
      printf(">%s'%s' : '%s' , %d\n",newsent,theinput,aword,otherch);
#endif

      ministr[0]=otherch;
      strcat(newsent,substit(aword));
      strcat(newsent,ministr);

    }
  strcpy(s,newsent);

}

//enables $variable translation
void eliza::addrest(char* replied, char* talker,
		    char* rep,char* target,char* rest)
{
  trim(rest);
  char* i;
  char* point   = replied;
  char* str     = rep;
  char* toofar = replied+repsize-1;
	while ( *str != '\0')
	{
		if ( *str != '$' )
		{
      *point++ = *str++;
			if(point==toofar) 
			{
				*point='\0'; return;
			}
      continue;
    }
    ++str;
    switch( *str )         /*add $Variable commands here*/
      {
      case 'n':
        i=talker;
        break;
      case 't':
        i=target;
        break;
      case 'r':
        i=rest;
        break;
      case '$':
        i="$";
        break;
      case 0:
        continue;
      case 'A':  //dont change THIS - Chris Busch  //author
			i=(char*)eliza_title;
			break;
      case 'V': //dont change THIS!   //Version
			i=(char*)eliza_version;
			break;
      case 'C': //dont change this!  //Compile time
			i= __DATE__ " " __TIME__;
			break;
      default:
			i="$UNDEFINED";
			break;
      }
    ++str;
		while ( ( *point = *i ) != '\0' )
		{
      ++point;
      ++i;
			if(point==toofar) 
			{
				*point='\0'; return;
			}
    }
  }
  *point++ = '\0';
}

//nothing can be NULL!!!
char* eliza::processdbase(char* talker,char* message,char* target,int dbase)
{
	static char replied[repsize];
	char *rep=NULL;

	if( dbase<0 || dbase>numdbases) return "dbase error in processnumber";

  	if(strlen(message)>MAXSIZE) return "You talk too much.";

  	strcpy(replied,"I dont really know much about that, say more.");

  	reducespaces(message);
  	trim(message);
  	int overflow=10; //runtime check so we dont have circular cont jumps
  	do
	{
	  thekeys[dbase].reset();
	  while(thekeys[dbase].curr()!=NULL)
	  {
		  int i=0,rest=0;
		  if(match(thekeys[dbase].curr()->key.getlogic(),message,i,rest))
        {
			  rep=thekeys[dbase].curr()->key.getrndreply();
			  fixgrammer(&message[rest]);
			  addrest(replied,talker,rep,target,&message[rest]);
			  reducespaces(replied);
			  return replied;
        }
		  thekeys[dbase].advance();
	  }
		dbase=thekeys[dbase].contdbase;
		overflow--;
	}
	while(dbase>=0 && overflow>0);
	if(overflow <=0)
	{
    return "potential circular cont (@) jump in databases";
  }
  return replied;
}

bool eliza::loaddata(char file[],char recurflag)
{
  //NOTE!!!! numdbases is the count of dbases!!!
  if(numdbases>=maxdbases) return false;

  FILE *data;
  char str[MAXSIZE];
  if((data=fopen(file,"rt"))==NULL)
    {
#ifdef DEBUG
      puts("File error!");
#endif
      return false;
    }
  int linecount=0;

  while(fgets(str,MAXSIZE-1,data)!=NULL)
    {
      linecount++;
#ifdef DEBUG
      puts(str);
#endif
      trim(str);
		 if(strlen(str)>0)
		 {
          if(str[0]>='1' && str[0]<='9')
			 {
				 thekeys[numdbases].curr()->key.addreply( str[0]-'0', &(str[1]) );
#ifdef DEBUG
            //puts("reply found");
#endif
			}
			else switch(str[0])
				 {
				  case '\0' :
					 break;
				  case '(':
					 thekeys[numdbases].addkey();
					 thekeys[numdbases].curr()->key.addlogic(str);
#ifdef DEBUG
            //puts("logic found");
#endif
					 break;
          case '#':
#ifdef DEBUG
            puts("rem");
#endif
            break;
          case '"':
            fprintf(stderr,"%s\n",&str[1]);
            break;
          case '\'':
            fprintf(stdout,"%s\n",&str[1]);
            break;
          case '>': //add another database
            if(numdbases<maxdbases-1) numdbases++;
            else
	      fputs("response database is full. numdbases>maxdbases",stderr);
				if(!addbunch(&str[1],numdbases) )
				{
              puts("name database is full.");
            }
            break;
	  case '%': //include another file inline
	    trim(str+1);
	    if(!loaddata(str+1,1)) //recurflag set
	      printf("including inline '%s' failed at %d!\n",str+1,linecount);
	    break;
	  case '@': //add continue to another database jump
				if(thekeys[numdbases].contdbase==allkeys::contnotset)
				{
	      trim(str+1);
	      for(char* i=str+1;*i!=0;i++) if(*i=='_') *i=' ';
	      sortnames();
	      int contd=getname(str+1);
	      thekeys[numdbases].contdbase=contd;
//	      printf("found cont link %s to %d\n",str,contd);
				}
				else
	      printf(" @ continue already used for database %d at %d\n"
		     ,numdbases,linecount);
	    break;
	  default:
            printf("extraneous line: '%s' at %d\n",str,linecount);
          }
        }
    }
  fclose(data);
	if(!recurflag)
	{
    numdbases++;
    sortnames();
  }
  return true;
}

char* eliza::trim(char str[])
{
  int i,a,ln;
  for(ln=strlen(str);(ln>0) && (str[ln-1]<=' ');ln--);
  str[ln]=0;
  for(i=0;(i<ln) && (str[i]<=' ');i++);
  if(i>0)
    for(ln-=i,a=0;a<=ln;a++)
      str[a]=str[a+i];
  return str;
}

int eliza::doop(char op,int a,int b)
{
  switch(op)
    {
    case '\0':
    case '&': return a && b;
            case '|': return a || b;
            case '~': return a && !b;
            default:
#ifdef DEBUG
              printf("Errored Op! %c\n",op);
#endif
              return 0;
            }
}

int eliza::lowcase(char ch)
{
  if(ch>='A' && ch<='Z') return ch+32;
  return ch;
}

int eliza::strpos(char *s,char *sub)
{
  int i,a,lns=strlen(s),lnsub=strlen(sub),run,space=1;
	if(sub[0]=='=')
	{
		// = exact equality operator
    return strcasecmp(&sub[1],s) ? 0 : lns;
  }
	if(sub[0]=='^')
	{
		// match start operator
    return strncasecmp(&sub[1],s,lnsub-1) ? 0 : lns;
  }
  if(lnsub>lns) return 0;

  run=lns-lnsub;
  for(i=0;i<=run;i++)
    {
      if(space)
        {
          for(a=0;a<lnsub && (lowcase(s[i+a])==sub[a]);a++);
#ifdef DEBUG
          //printf("hey %d r:%d",a,i+a);
#endif
          if(a==lnsub) return (i+a);
        }
      space=s[i]==' ';
    }

  return 0;
}

#define encounterop                  \
trim(ph);                    \
if(strlen(ph))               \
{                            \
        a=strpos(m,ph);      \
        if(a>0) rest=a;      \
        res=doop(op,res,a);  \
}                            \
len=ph[0]=0;

int eliza::match(char s[],char m[],int& in,int& rest)
{
  int l=strlen(s),res=1,op='\0',a;
  char ph[MAXSIZE];
  int len=0;
  ph[0]=0;
#ifdef DEBUG
  //puts(s);
  //puts(m);
#endif
  while(s[in]!='(') in++;
  in++;
  for(;in<l;in++)
    {
      switch(s[in])
        {
        case '(':
#ifdef DEBUG
          //printf("in %d into...\n",in);
#endif
          a=match(s,m,in,rest);
          if(op=='\0') res=a;
          else
            res=doop(op,res,a);
          break;
        case '&':
          encounterop
            op='&';
          break;
        case '|':
          encounterop
            op='|';
          break;
        case '~':
          encounterop
            op='~';
          break;
        case ')':
#ifdef DEBUG
          //printf("p:'%s'\n",ph);
#endif
          trim(ph);
          if(strlen(ph))
            {
              a=strpos(m,ph);
              if(a>0) rest=a;
              return doop(op,res,a);
			}
			else return res;

          break;
        default:
          ph[len++]=s[in];
          ph[len]='\0';
        }

    }
  return res;
}