/**
 *
 * Project 1 - Refugee water needs calculator
 *
 * @author Clay Shields
 *
 **/

#include <iostream>
#include <math.h>
using namespace	std;

int 
main()
{

	const double	minWaterPerPersonPerDay = 7.5;
	const double	maxWaterPerPersonPerDay = 15;

	const double	tapLitersPerMinute = 7.5;
	const double	pumpLitersPerMinute = 17;
	const double	wellLitersPerMinute = 12.5;

	const double	litersToGallons = 3.78541;
	const double	waterBufffaloCapacityGallons = 400;
	const double	waterBuffaloCapacityLiters = 400 * litersToGallons;

	const int	minutesWaterPerDay = 60 * 8;

	int		numberOfRefugees = 0;
	double		litersPerDayPerPerson = 0;
	int		numberOfTaps = 0;
	int		numberOfWells = 0;
	int		numberOfPumps = 0;
	int		numberOfBuffalosNeeded = 0;

	double		waterNeeded = 0;
	double		waterAvailable = 0;
	int		refugeeCapacity = 0;
	double		waterDeficit = 0;

	cout << "This program will determine the water needs for a refugee camp" << endl;
	cout << "based on the number of refugees, daily water needs, and the existing" << endl;
	cout << "water supplies." << endl << endl;

	cout << "Please enter the number of refugees: ";
	cin >> numberOfRefugees;
	cout << endl;

	cout << "Please enter the daily water needs for each person (in the range" << endl;
	cout << minWaterPerPersonPerDay << " liters/day to " << maxWaterPerPersonPerDay
		<< " liters/day):";
	cin >> litersPerDayPerPerson;

	if ((litersPerDayPerPerson < minWaterPerPersonPerDay) ||
	    (litersPerDayPerPerson > maxWaterPerPersonPerDay)) {

		cout << "WARNING: The water needs entered seem out of range for the minimum" << endl;
		cout << " standards in water supply, sanitation and hygiene promotion according" << endl;
		cout << "to the Sphere Project Minimum Standards in Humanitarian Response" << endl;

	}
	if (litersPerDayPerPerson <= 0) {
		cout << "Zero liters per day will lead to death." << endl;
		return 0;
	}
	cout << "Enter the number of working taps in the camp: ";
	cin >> numberOfTaps;
	cout << "Enter the number of working pumps in the camp: ";
	cin >> numberOfPumps;
	cout << "Enter the number of working wells in the camp: ";
	cin >> numberOfWells;
	cout << endl << endl;


	//Calculate the daily water needs
		waterNeeded = litersPerDayPerPerson * numberOfRefugees;

	//Calculate the water available

		waterAvailable = (((numberOfTaps * tapLitersPerMinute) +
				   (numberOfPumps * pumpLitersPerMinute) +
				   (numberOfWells * wellLitersPerMinute))
				  * minutesWaterPerDay);

	if (waterNeeded < waterAvailable) {
		refugeeCapacity = (waterAvailable - waterNeeded) / litersPerDayPerPerson;
		cout << "There is adequate water for the camp, which can support an additional "
			<< refugeeCapacity << " people" << endl;
	} else {
		waterDeficit = waterNeeded - waterAvailable;
		cout << "The camp is short of water by " << waterDeficit << " liters/day." << endl;;
		numberOfBuffalosNeeded = ceil(waterDeficit / waterBuffaloCapacityLiters);
		cout << "You will need to provide as additional " << numberOfBuffalosNeeded << " M149 Water Buffalos per day" << endl;
	}

}