/*
$              pooya laryan
$
$        compiler - scanner design
$
*/


#include<iostream.h>
#include<fstream.h>
#include<conio.h>
#include<stdlib.h>
#include<string.h>
#include<stdio.h>


int removeblank(char [][15],int);
int chk(char [][15],int);
int scanner(char [],char []);
int isnumber(char []);

void main(void)
{
   char line[255],tokens[100][15],*pl,key,tokentype[25];
   int  i=0,j=0;
   fstream file;

   file.open("c:\\input.orb",ios::in|ios::out);
   if(!file)
     exit(0);

   clrscr();

   while(!file.eof())
   {
      file.getline(line,255);
      pl=line;
      j=0;
      for(int ln=0;ln<=strlen(line);ln++)
      {
	 if(*pl!=0 && *pl!=32)
	   {
	       // if *pl is not Blank
	       if(*pl=='*' || *pl=='/' || *pl=='+' || *pl=='-' ||
		  *pl==')' || *pl=='(' || *pl==':' || *pl=='.' ||
		  *pl==',' || *pl==';' || *pl=='>' || *pl=='<' || *pl=='=' )
		{
		   char temp=*pl;
		   tokens[i][j]='\0';
		   i++;
		   tokens[i][0]=temp;
		   tokens[i][1]='\0';
		   i++;
		   j=0;
		}
		else
		{
		   tokens[i][j]=*pl;
		   j++;
		}
	   }
	 pl++;
      }// end of line
      tokens[i][j]='\0';
      i++;
   }   // end of file set eof
   file.close();

   i=removeblank(tokens,i);
   i=chk(tokens,i);
   j=0;
   while(j<=i-1)
     {
       scanner(tokens[j],tokentype);
       cout<<tokens[j]<<"\t"<<tokentype<<endl;
       if((key=getch())==13)
	 j++;
       else if(key==8)
       {
	 j--;
	 if(j<0)
	 {
	   j=0;
	   cout<<"<<<<< BEGIN OF FILE >>>>>";
	 }
       }
     }
   //gotoxy(40,5);
   cout<<endl<<endl<<"End of SCAN"<<endl<<"Press Any key to Exit...";
   getch();
}

//---------------------------------------------------
int removeblank(char table[][15],int size)
{
  for(int i=0;i<=size;i++)
     if(strlen(table[i])==0)
     {
	for(int j=i;j<=size;j++)
	      strcpy(table[j],table[j+1]);
	size--;
     }
  return size;
}
//---------------------------------------------------
int chk(char table[][15],int size)
{
   for(int i=0;i<=size;i++)
      if(table[i][0]==':' ||table[i][0]=='<' || table[i][0]=='>')
	  if(table[i+1][0]=='=')
	    {
		table[i][1]=table[i+1][0];
		table[i][2]='\0';
		i++;
		for(int j=i;j<=size;j++)
		  strcpy(table[j],table[j+1]);
		size--;
	    }
     return size;
}
//------------------------------------------------------
int scanner(char word[],char tokentype[])
{
      if(strcmp(word,"+")==0 || strcmp(word,"*")==0 || strcmp(word,"-")==0
	|| strcmp(word,"/")==0 || strcmp(word,"mod")==0 || strcmp(word,"div")==0
	|| strcmp(word,">")==0 || strcmp(word,">=")==0
	|| strcmp(word,"<")==0 || strcmp(word,"<=")==0
	|| strcmp(word,"=")==0 || strcmp(word,":=")==0
	|| strcmp(word,",")==0 || strcmp(word,";")==0
	|| strcmp(word,".")==0 || strcmp(word,")")==0
	|| strcmp(word,"(")==0 || strcmp(word,":")==0)
		 strcpy(tokentype,"Operator");
      else if(strcmp(word,"integer")==0 || strcmp(word,"real")==0 )
		 strcpy(tokentype,"Variable type");
      else if(strcmp(word,"if")==0 || strcmp(word,"else")==0
	      || strcmp(word,"then")==0 || strcmp(word,"elseif")==0
	      || strcmp(word,"do")==0  || strcmp(word,"while")==0
	      || strcmp(word,"end")==0 || strcmp(word,"array")==0
	      || strcmp(word,"procedure")==0 || strcmp(word,"function")==0
	      || strcmp(word,"const")==0 || strcmp(word,"var")==0
	      || strcmp(word,"begin")==0 || strcmp(word,"type")==0
	      || strcmp(word,"write")==0 || strcmp(word,"writeln")==0
	      || strcmp(word,"read")==0  || strcmp(word,"readln")==0)
		 strcpy(tokentype,"Special Word");
      else if(isnumber(word)==0)
		 strcpy(tokentype,"Identifier");
      else
		 strcpy(tokentype,"Integer Number");
}
//------------------------------------------------
int isnumber(char word[])
{
   for(int i=0;i<=strlen(word)-1;i++)
     if(word[i]>='a' && word[i]<='z')
	return 0;
   return 1;
}