//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//+      Student:          Junshan Li                                  +
//+      Proj. Assignemnt: Two                                         +
//+      Due Date:         Febuary 12, 2001                            +
//+      Course Name:      MSCS 518 - Compiler Design                  +       
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// FileManager.cpp
// Implementing FileManager class.

#include <iostream.h>
#include "FileManager.h"
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// FileManager class constructor.
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
FileManager::FileManager() {
   ENDOFPROGRAM = false;
   lineNumber = 0;
   for (int i = 0; i < STRSIZE; i++) {  // initialize fileName array with nil.
      fileName[i] = '\0';
   }
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func1. Opens the named file fileName if it exists or else write an error 
// message and terminate.
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::retrieveProgram(char * aFileName) {
   fin.open(aFileName);
   if (fin.fail()) {
     cout << "Input file: " << aFileName << " opening failed!!!\n";
     exit(1);
   }
   storeFileName(aFileName);
   ENDOFPROGRAM = false;
}  // end of function retrieveProgram()

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func2. Saves fileName in a char array (string) fileName[].
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::storeFileName(char * aFileName) {
   strcpy(fileName, aFileName);
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func3. Retrieve the stored file name from the char array: fileName[].
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
char* FileManager::getProgramName() {
   return fileName;
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func4. Close the file that was opened.
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::closeProgram() {    // closes the file that was openned;
   fin.close();
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func5. Reads and returns the next charactor of the input file.
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
char FileManager::getNextChar()  {  // reads and returns next character in file
   char nextChar;

   fin.get(nextChar);
   if (fin.eof()) {
      ENDOFPROGRAM = true;
   }

   //cout << "In FileManager::getNextChar(), nextChar == " << nextChar << endl;
   return toupper(nextChar);
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func6. Returns the next charactor of the input file without extraction. 
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
char FileManager::peekNextChar() { // returns the next char without extraction.
   // istream's member function peek does the job.
   char nextOne;
   nextOne = fin.peek();

   return nextOne;
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func7. Displays the entire input file to out put device with line number 
//        in front of each line.
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::seeProgramFile() {
   // displays entire file on output device (include
   // line number for each program line
   char buffer[STRSIZE];

   while (1) {
      fin.getline(buffer, STRSIZE);
      if (fin.eof()) break;
      lineNumber++;
      cout << "Line " << lineNumber << ": " << buffer << endl;
   }
   closeProgram();
   retrieveProgram(fileName);
}

// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func8. Internal Use Only.  Returns the total number of lines of the input
//        file.  Used by function seeErrorLines().
// +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
int FileManager::countLines() {
   char buffer[STRSIZE];
   int lineNumber1 = 0;

   retrieveProgram(fileName);
   while (1) {
      fin.getline(buffer, STRSIZE);
      if (fin.eof()) break;
      lineNumber1++;
   }
   closeProgram();
   
   return (lineNumber1 - 1);
}

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func9. Displays 2 contiguous lines of a file where an error may be detected.
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::seeErrorLines(int lineNum) {
   // displays 2 contiguous lines of file starting with line=lineNum
   // if lineNum greater than 1 else display only first line.
   int n = 1;

   retrieveProgram(fileName);

   while (!fin.eof()) {
      fin.getline(buffer, STRSIZE);
      if ( (n == lineNum - 1) || (n == lineNum) ) {
         cout.width(3);
         cout << "Error in " << n << "   " << buffer << endl;
      }  // end of if
      n++;
   }  // end of while loop.
   closeProgram();
}

// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// func10. Initialized lineNumber to 0.
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
void FileManager::initLineNumber() {
   lineNumber = 0;
}