/**************************************************************************/
/*  CSE2304 Prac3A Sample Source Code                                     */
/**************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include "global.h"
#include "routines.h"

/* this function initializes the necessary routines and variables */
void init( ) 
{
  int i;
  char * reserved_words_parameter_file="reserved_words";
  char * operators_parameter_file="operators";
  char * punctuations_parameter_file="punctuations";
  flag_single_quote=OFF;
  flag_double_quote=OFF;
  flag_number=OFF;
  flag_letter=OFF;
  for(i=0;i<100;i++) buffer[i]='\0';
  position=0;

  reserved_words=init_list_reserved_words(reserved_words_parameter_file);
  operators=init_list_operators(operators_parameter_file);
  punctuations=init_list_punctuations(punctuations_parameter_file);
  white_space=init_white_space();

  counter_string=0;
  counter_char=0;
  counter_identifier=0;
  counter_number=0;
  counter_comment=0;

}


/* this function parses the read character and does necessary classification and updates the statistics
 * it's the central part of the program
 */
void process(int input)
{
  int is_reserved_word, is_operators;
  int idx;
  int i;

  /***************** when the status of the flag_double_quote is ON *********/ 
  if((flag_double_quote==ON)&&(input!='\"'))
    {
      return;
    }

  /***************** when the status of the flag_single_quote is ON *********/
  if((flag_single_quote==ON)&&(input!='\'')) 
    {
      return;
    }

  /***********************when the status of the flag_comment is ON *******/ 
  if(flag_comment==ON)
  {
    if((input=='*')&&(position==0))
      {
	buffer[0]='*';
	position++;
	return;
      }
    if((input=='/')&&(buffer[0]=='*')&&(position==1))
      {
	flag_comment=OFF;
	position=0;
	for(i=0;i<100;i++) buffer[i]='\0';
	return;
      }
    else return;
  }


  /**********************when the status of the flag_number is ON ************/
  if((flag_number==ON) && !(((input>=48)&&(input<=57))||(input==46)||(input=='e')||(input=='-')||(input=='+'))) /* please check ASCII table for the values I use here */
    {
      flag_number=OFF;
      update_numbers();
     
    }

  if((flag_number==ON) &&(input=='e'))
    {
      for(i=0;i<position;i++)
	{
	  if(buffer[i]=='e')
	    {
	      flag_number=OFF;
	      position=0;
	      for(i=0;i<100;i++) buffer[i]='\0';
	      update_numbers();
	      return;
	    }
	}
      
      buffer[position++]=input;
      return;
	 
    }

  if((flag_number==ON) && ((input=='+')||(input=='-')))
    {
      for(i=0;i<position;i++)
	{
	  if(buffer[i]=='e')
	    {
	      buffer[position++]=input;
	      return;
	    }
	}
      flag_number=OFF;
      for(i=0;i<100;i++) buffer[i]='\0';
      position=0;
      update_numbers();
    }

  /**********************when the status of the flag_letter is ON ************/
  if((flag_letter==ON) &&!(((input>=65)&&(input<=90))||((input>=97)&&(input<=122))||(input=='_')||((input>=48)&&(input<=57)))) /* what if input is not a lexical letter ? */
    {
      flag_letter=OFF;
      is_reserved_word=search_reserved_words(reserved_words,buffer,&idx);
      if(is_reserved_word==ON) update_reserved_words(reserved_words,idx);
      else update_identifiers();
      for(i=0;i<100;i++) buffer[i]='\0';
      position=0;
     }

  if((flag_letter==ON)&&((input=='_')||((input>=48)&&(input<=57))))
  {
    buffer[position++]=input;
    return;
  }

  /******************when the status of the flag_operator is ON **************/
  if(flag_operator==ON)/* what if input is not a operator letter ? */
    {
      if(!is_operator_char(input))
	{
	  flag_operator=OFF;
	  is_operators=search_operators(operators,buffer,&idx);
	  if(is_operators==ON)
	    {
	      update_operators(operators, idx);
	      for(i=0;i<100;i++) buffer[i]='\0';
	      position=0;
	    }
	  else if ((buffer[0]='/')&&(input=='*')&&(position==1))
	    {
	      flag_comment=ON;
	      buffer[0]=0;
	      position=0;
	      return;
	    }
	}
      else if(input=='*')
	{
	  if(buffer[0]=='/')      /* the previous input is '/'  */
	    {
	      flag_operator=OFF;
	      flag_comment=ON;
	      for(i=0;i<100;i++) buffer[i]='\0';
	      position=0;
	      return;
	    }
	}

      else
	{
	  buffer[position++]=input;
	  return;
	    
	}

    }

  /* when the current symbol is white space symbol */  
  if((flag_single_quote==OFF)&&(flag_double_quote==OFF)&&(input==' '))
  {
    position=0;
    for(i=0;i<100;i++) buffer[i]='\0';

    //  search_white_space(white_space,input,&idx); 
    //  update_white_space(white_space,idx);  
    return;
  }

  /* if the current symbol is single quote mark */
  else if(input=='\'')  /* process the '\' */
    {
      if(flag_single_quote==OFF) 
	{
	  flag_single_quote=ON;
	  return;
	}
      else
	{ 
	  update_characters();
	  flag_single_quote=OFF;
	  return;
	}
    }

  /* if the current symbol is double quote mark */
  else if(input=='\"')   /* process the '\"' */
    {
      if(flag_double_quote==OFF)
	{
	  flag_double_quote=ON;
	  return;
	}
      else
	{
	  update_strings();
	  flag_double_quote=OFF;
	  return;
	}
    }

  if(((input>=48)&&(input<=57))||(input==46))  /* see if input is a number */
  {
    if(flag_number==OFF)
      {
	flag_number=ON;
	for(i=0;i<100;i++) buffer[i]='\0';
	position=0;
	buffer[position++]=input;
	return;
      }
    else
      {
	buffer[position++]=input;
	return;
      }
  }

  if(((input>=65)&&(input<=90))||((input>=97)&&(input<=122))||(input=='_'))/* see if input is a lexical letter */
    {
      if(flag_letter==OFF)
	{
	  flag_letter=ON;
	  buffer[position++]=input;
	  return;
	}
      else
	{
	  buffer[position++]=input;
          return;
        }
    }

  if((input==';')||(input==',')||(input=='(')||(input==')')||(input=='{')||(input=='}')||(input=='[')||(input==']'))/* please check ASCII table for the values I use here */
  {
      
    if(flag_letter==ON) 
      {
	flag_letter=OFF;
	is_reserved_word=search_reserved_words(reserved_words,buffer,&idx);
	if(is_reserved_word==ON) update_reserved_words(reserved_words,idx);
	else update_identifiers();
	for(i=0;i<100;i++) buffer[i]='\0';
	position=0;
     }
    else if(flag_number==ON)
      {
	flag_number=OFF;
	update_numbers();
	for(i=0;i<100;i++) buffer[i]='\0';
	position=0;
      }

    search_punctuations(punctuations,input,&idx);
    update_punctuations(punctuations,idx);
    for(i=0;i<100;i++) buffer[i]='\0';
    position=0;
    return;
 
  }

  if(is_operator_char(input)) /* whether the current input is an operator symbol?*/
  {
    if(flag_operator==OFF)
      {
	flag_operator=ON;
	buffer[position++]=input;
	return;
      }
    else
      {
	buffer[position++]=input;
	return;
      }
  }

  return;
}

/* this function calculates and output the final results */
void end( ) 
{
  calculate_and_print_results();
  end_list_reserved_words(reserved_words);
  end_list_operators(operators);
  end_list_punctuations(punctuations);
  end_white_space(white_space);
}

int main(int argc, char *argv[])
{
  int input;
  FILE *fp;
  if(argc<2) 
    {
      printf("The Usage of the program is:\n");
      printf("prac3a [c program file]\n");
      exit(0);
    }

  if((fp=fopen(argv[1],"r"))==NULL)
    {
      printf(" The program can't open the c source file, please check the directory and the file name\n");
      exit(0);
    }

  init();

  while((input=fgetc(fp))!=EOF)
    {
      process(input);
    }


  printf(" The source file is successfully parsed!\n");
  end(); 
  printf(" Game Over! Thanks for your Using!\n");
  exit(0);  

}