//                  -*- mode:c++; tab-width:4 -*-
// File: tools.cpp - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
//  the tools library.
//  Assorted utility routines for use in C++ programs.
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#include "tools.hpp"

// --------------------------------------------------------------------------
// I/O Utilities. -----------------------------------------------------------
// ---------------------------------------------------------------------------
// Used to flush the cin buffer as in cin >> x >> flush;  or cin >> flush;
istream&
flush( istream& is ) {  return is.seekg( 0, ios::end ); }

// ---------------------------------------------------------------------------
// Print a neat header on the output.

void
fbanner( ostream& fout )
{   char date[16], time[10];
    when(date, time);
    fout << "\n---------------------------------------------------------------\n"
         << "\t" << NAME
         << "\n\t" << CLASS << "\n\t" <<  date << "\t" << time << endl
         << "---------------------------------------------------------------\n";
}

// ---------------------------------------------------------------------------
//  Print termination message.

void bye( void ) {
    cout << "\n---------------------------------------------------------------"
            "\nNormal termination.\n" ;
}

// --------------------------------------------------------------------------
//  This is a handy function for messages of all sorts.
//  It formats and prints a message.
//  params: a format followed by a variable number of data items to print.

void
say (const char* format, ...)
{   va_list vargs;                               // optional arguments

    va_start(vargs, format);
    vfprintf(stdout, format, vargs);
    fprintf(stdout, "\n");
}


// --------------------------------------------------------------------------
// Delay progress of program for some number of seconds using a "busy wait".

void
delay( int seconds )
{
    do { seconds = sleep( seconds ); } while (seconds > 0);
}

// ----------------------------------------------------------------------------
//  Error handling and error recovery.
//-----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
// This function is for error messages.
//    It takes a format argument followed by any number of data arguments.
//    It formats and prints an error message, then exits.

void
fatal (const char* format, ...)
{   va_list vargs;                               // optional arguments

    cout << flush;
    va_start(vargs, format);
    vfprintf(stdout, format, vargs);
    fprintf(stdout, "\n");
    exit(1);
}

// ----------------------------------------------------------------------------
// Routines for handling the time and date.
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
// Store the current date and time in the arguments.
//      System's date format is: "Fri Jun  9 10:15:55 1995\n"
//      After extraction, date is: "Fri Jun  9 1995"    hour is: "10:15:55"

void
when( cstring date, cstring hour)
{
    time_t now;           // Stores an integer encoding of the date and time.
    char* nowstring;    // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);                   // Convert to string form.
    strncpy( date, nowstring, 10);             // Extract day, month, date.
    strncpy( &date[10], &nowstring[19], 5);    // Extract space and year.
    date[15]  = '\0';                          // Add the string terminator.
    strncpy( hour, &nowstring[11], 8);         // Copy hour:minutes:seconds.
    hour[8]  = '\0';                           // Add the string terminator.
}

// ----------------------------------------------------------------------------
// Store the current date in the argument and return a pointer to it.
//      date format is: "Fri Jun  9 1995"

cstring
today( cstring date )
{
    time_t now;          // Stores an integer encoding of the date and time.
    cstring nowstring;   // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);                   // Convert to string form.
    strncpy( date, nowstring, 10);             // Extract day, month, date.
    strncpy( &date[10], &nowstring[19], 5);    // Extract space and year.
    date[15]  = '\0';                          // Add the string terminator.
    return( date );
}

// ----------------------------------------------------------------------------
// Store the current time in hour and return a pointer to it.
//      hour format is: "10:15:55"

cstring
oclock( cstring hour)
{
    time_t now;          // Stores an integer encoding of the date and time.
    cstring nowstring;   // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);              // Convert to string form.
    strncpy( hour, &nowstring[11], 8);    // Extract hour, minutes, seconds.
    hour[8]  = '\0';                      // Add the string terminator.
    return( hour );
}