// Author: Matt Johnson
// FileName: parsedTokens.h 
// Course: CS 284 - Operating Systems
// Section: A 
// Instructor: Matt Johnson 
// 
// This is the header file which contains the class definition of the 
// parsedTokens class. The job of the parsedTokens class is to parse out the 
// command line and store the tokens.
// 
// Current Version is 1.0.
// 
// Revision History
// ------------------------------------------------------------------------
// Version 0.1:
// Spring Semester 2004
// - Created class.  
// Version 0.2: 
// Spring Semester 2004
// - Added the ability to execute a basic command from from the command line.
// - Added a PrintTokens function which will output the data stored in the 
//   object.
// ------------------------------------------------------------------------
// Version 1.0:
// September 15, 2004
// - Cleaned up class for use by students in CS 284.
// - Class parses and stores the command line tokens.
// ------------------------------------------------------------------------

#ifndef parsedTokens_h
#define parsedTokens_h

#include <string>
#include <vector>
#include <iostream>
#include <fstream>

using std::vector;
using std::string;

class ParsedTokens
{
   public:
      // PreConditions:  None. 
      // PostConditions: Object is created. 
      ParsedTokens();

      // PreConditions:  None.
      // PostConditions: Object is destroyed.
      ~ParsedTokens();

      // PreConditions:  The char* argument must be a command line from the 
      //                 shell. It should be properly formatted and delimited. 
      // PostConditions: Tokens are removed and added to this container. 
      void ParseAndAddTokens(char * commandLine);

      // PreConditions:  None.
      // PostConditions: Internal iterator starts at the beginning of the 
      //                 containter. 
      void StartIterator();

      // PreConditions:  None.
      // PostConditions: The inToken argument has been set to the next token.
      //                 If the operation has succeeded, it will return true.
      //                 Otherwise, it will return false. 
      bool GetNextToken(std::string &inToken);

      // PreConditions:  The ostream object must be open and ready for writing. 
      // PostConditions: Contents of the container will be sent to the ostream
      //                 object.
      void PrintTokens(std::ostream &ofile, char *args[] = 0);

      // PreConditions:  None. 
      // PostConditions: Container is empty.
      void Clear();

      // PreConditions:  None. 
      // PostConditions: Returns the number of tokens stored.
      unsigned int GetNumTokens();

      unsigned int GetNumPipes();

      string operator[](unsigned int index);

   private:
      // PreConditions:  None.
      // PostConditions: Function will return true or false, which will 
      //                 indicate whether the input character is a delimiter.
      bool IsDelimiter(char ch);

      // PreConditions:  User must specify whether to add the special character
      //                 to the container with the second bool argument.
      // PostConditions: Function will return true or false, which will 
      //                 indicate whether the input character is a special
      //                 character. If the character is indeed a special 
      //                 character, and the user specified true in the second
      //                 argument, that character will be added to the 
      //                 container as a seperate token.
      bool IsSpecialCharacter(char ch, bool addToContainer);

      std::vector<std::string> tokens_;
      unsigned int iterCount_;
};

#endif