The Object-Oriented Text Star Trek Game in C++

/* ---------------------------------------------------------
Super Star Trek
C++ Port Copyright 2008, James M. Curran    <jamescurran@mvps.org>
based upon the C Port, Copyright 1996, Chris Nystrom
based upon the PC Basic port, Copyright 1978, Workman Publishing
based upon the HP Basic original, PD circa 1971, Mike Mayfield

C++ code licensed using the Code Project Open License v1.02
http://www.codeproject.com/info/cpol10.aspx
 -------------------------------------------------------------- */
// Shields.cpp: implementation of the Shields class.
//
//////////////////////////////////////////////////////////////////////

#include "Shields.h"
#include "Ship.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

Shields::Shields(Ship& s): ShipSystem(s)
{
	nLevel = 0;
}

Shields::~Shields()
{

}


bool Shields::activate()
{
	cout << "Energy available = " << ship.Energy() + GetLevel() << endl << endl;

	cout << "Input number of units to sheilds: ";

	int	   nNewShields;
	cin >> nNewShields;

	cout << endl;

	if ( (nNewShields < 0)  || nLevel == nNewShields)
    {
      cout << "<Sheilds Unchanged>" << endl << endl;
    }
	else
	{
		if (nNewShields >= ship.Energy() + nLevel)
		{
			cout << "Sheild Control Reports:" << endl;
			cout << "  'This is not the Federation Treasury.'" << endl;
			cout << "<Sheilds Unchanged>" << endl << endl;
		}
		else
		{
			ship.AddEnergy(nLevel);			// put back what we were using
			ship.UseEnergy(nNewShields);	// remove what we are using.
			SetLevel(nNewShields);

			cout << "Deflector Control Room report:" << endl;
			cout << "  'Shields now at " << nLevel << " units per your command.'" << endl << endl;
		}
	}
	return(true);
}

int Shields::BorrowFromReserves(int eng)
{
	int energy = std::min(this->nLevel, eng);
	nLevel -= energy;
	return energy;
}