/* Filename:  readform.cpp

   Author:  Br. David Carlson

   Date:  February 1, 1998

   Revised:  July 13, 2000 to use modern headers.

   This program prompts the user for the name of a file to read.  This
   must be a formatted text file as created by the makeform program.
   It assumes that each product name consists of just one word of up to
   40 characters.  The data from the file is displayed on the screen.
*/

#include <iostream>
#include <iomanip>
#include <fstream>   // needed for files
using namespace std;


const int MaxString = 120;

typedef char StringType[MaxString];


/* Given:  InStream     An input file stream already open for reading.
           StringMax    The maximum number of characters that can be put
                        into String, including the NULL that marks the
                        end of the string.
   Task:   To read up to StringMax - 1 characters from InStream, storing
           them in String, but stopping if a newline is read or end of
           file or an error condition is reached.
   Return: String       The string just read, with a NULL appended to
                        mark the end of the string.  If a newline was
                        read, it is not stored in String.
           The number of characters read into String (not counting the NULL)
           is returned in the function name.
*/
int MyGetLine(istream & InStream, char * String, int StringMax)
   {
   char Ch;
   int Count, Last;

   Count = 0;
   Last = StringMax - 1;
   Ch = InStream.get();

   while ((Ch != '\n') && (! InStream.fail()))
      {
      if (Count < Last)
         String[Count++] = Ch;
      Ch = InStream.get();
      }

   String[Count] = NULL;
   return Count;
   }


/* Given:   InFile   A file stream already opened for input.
   Assumes: That InFile is associated with a text file of the type 
            described at the top of this program.
   Task:    To read the data from InFile and display it on the screen.
   Return:  InFile   The modified file stream.
*/
void DisplayFile(fstream & InFile)
   {
   StringType ProductName;
   float Price;
   int Count = 0;

   InFile >> ProductName;

   while (! InFile.fail())
      {
      InFile >> Price;
      InFile.get(); // read the newline and discard it
      cout << setw(40) << ProductName << setw(12) << Price
         << endl;
      Count++;

      if (Count == 22)
         {
         Count = 0;
         cout << "   Press ENTER to go on...";
         cin.get();
         }

      InFile >> ProductName;
      }

   if (Count != 0)
      {
      cout << "   Press ENTER to go on...";
      cin.get();
      }
   }


int main(void)
   {
   StringType FileName;
   fstream InFile;

   cout << "Enter the name of the text file to be read: ";
   MyGetLine(cin, FileName, MaxString);

   InFile.open(FileName, ios::in);
   if (InFile.fail())
      {
      cerr << "Could not open file " << FileName << endl;
      exit(1);
      }

   DisplayFile(InFile);
   InFile.close();
   return 0;
   }