import java.util.Scanner;

public class FootprintCalculator {

	public static void main(String[] args) {
		System.out.println("We will calculate the CO2 emissions for your transportation in a year. After answering a few of the following questions that appear. Please answer with numbers.");
		carbonPrivateAutoUseage();
		carbonPrivateAutoOwnership();
		carbonPublicTransport();
		carbonAirTransport();

		double kgCO2 = carbonPrivateAutoUseage();
		double kgCO2Car = carbonPrivateAutoOwnership();
		double kgC02OnBus = carbonPublicTransport();
		double totalHaul = carbonAirTransport();
		double overallTotal = carbonTotal(kgCO2, kgCO2Car, kgC02OnBus, totalHaul);
		printReport(kgCO2, kgCO2Car, kgC02OnBus, totalHaul, overallTotal);
	}

	public static Scanner userInput = new Scanner(System.in);

	// Total amount of carbon produce per year by driving a car
	public static double carbonPrivateAutoUseage() {
		System.out.println("How many liters of gasoline do you use per day?");
		double litersPerDay = userInput.nextDouble();
		System.out.println("How many kilometers do you drive per day?");
		double kmPerDay = userInput.nextDouble();
		double fuelEfficiency = kmPerDay/litersPerDay;
		double litresUsedPerYear = 365 * (kmPerDay/fuelEfficiency);
		double kgCO2 = 12.85 * litresUsedPerYear;
		return kgCO2;
	}

	// Total amount of carbon produced per year from owning a car
	public static double carbonPrivateAutoOwnership() {
		System.out.println("How old is your car?");
		double ageOfCar = userInput.nextDouble();
		double kgC02PerGJ = 1.94;
		double carbonManufactureCar = (kgC02PerGJ*120) + ((3.8*kgC02PerGJ)*ageOfCar);
		double kgCO2Car = carbonManufactureCar/ageOfCar;
		return kgCO2Car;
	}

	// Total amount of carbon produced per year by public transport
	public static double carbonPublicTransport() {
		System.out.println("How many kilometers do you ride the bus per day?");
		double busRide = userInput.nextDouble();
		double kgC02OnBus = (0.18*busRide) * 365;
		return kgC02OnBus;
	}

	// Total amount of carbon produced per year by air transport
	public static double carbonAirTransport() {
		System.out.println("How many kilometers in total have you flown on domestic flights this year?");
		double domesticFlight = userInput.nextDouble();
		System.out.println("How many kilometers in total have you flown on international flights this year?");
		double internationalFlight = userInput.nextDouble();
		double smallHaul = 0.10*domesticFlight;
		double bigHaul = 0.2*internationalFlight;
		double totalHaul = smallHaul+bigHaul;
		return totalHaul;
	}

	// Total amount of carbon produced per year in metric tons
	public static double carbonTotal(double kgCO2, double kgCO2Car, double kgC02OnBus, double totalHaul) {
		double overallTotal = (kgCO2 + kgCO2Car + kgC02OnBus + totalHaul)/1000;
		return overallTotal;
	}

	public static void printReport(double kgCO2, double kgCO2Car, double kgC02OnBus, double totalHaul, double overallTotal){
		System.out.println("You produce an annual total of metric " + overallTotal + " tons of CO2 per year for your personal transport.");
		System.out.println("The breakdown is as follows:");
		System.out.println("Private Automobile Usage          " + kgCO2);
		System.out.println("Private Automobile Ownership      " + kgCO2Car);
		System.out.println("Public Transport                  " + kgC02OnBus);
		System.out.println("Air Transport                     " + totalHaul);

	}
}