/**
 * This program demonstrates class inheritance by creating
 * the Circle class which is inherited by the Cylinder class.
 * It contains classic geometric functions such as area,
 * surface area and volume.
 *
 * @author     Francisco, Graham
 * @assignment ICS 212 Assignment 23
 * @date       4/25/2019
 */
#include <iostream>
using namespace std;

/**
 * This represents the class for circles. It contains the radius of the circle
 * and it can calculate its area.
 */
class Circle {

  /*
  Public variables and functions can be accessed outside
  the class definition, i.e. they can be used in main().
  */
  public:

    //Constant variable holding the value of Pi.
    static const double PI = 3.1415926;

    /**
     * Default constructor for the Circle class. Has no parameters.
     */
    Circle() {
      //default radius
      radius = 1.0;
    }

    /**
     * Additional constructor that allows the user to set a custom radius for
     * the circle.
     */
    Circle(double radiusParam) {
      //If input is negative, turn it to positive, if 0, set to default 1
      if (radiusParam < 0) {
          radius = radiusParam * -1.0;
      } else if (radiusParam == 0) {
          radius = 1.0;
      } else {
          radius = radiusParam;
      }
    }

    /**
     * Sets the circle's radius based on the user's input.
     */
    void setRadius(double radiusParam) {
      if (radiusParam < 0) {
          radius = radiusParam * -1.0;
      } else if (radiusParam == 0) {
          radius = 1.0;
      } else {
          radius = radiusParam;
      }
    }

    /**
     * Returns the radius of the circle.
     */
    double getRadius() const {
      return radius;
    }

    /**
     * Calculates and returns the area of the circle.
     */
    double area() {
        return PI * radius * radius;
    }

  /*
  Protected variables and functions cannot be accessed outside
  the class definition, i.e. they can't be used in main(). Although
  they are accessible by inherent classes.
  */
  protected:
    // protected data member
    double radius;
};

/**
 *
 */
class Cylinder: public Circle {

  /*
  Public variables and functions can be accessed outside
  the class definition, i.e. they can be used in main().
  */
  public:

    /**
     * Default constructor.
     * Constructs a Square object with 0 length and width.
     */
    Cylinder(double radiusParam, double heightParam): Circle(radiusParam) {
      //If input is negative, turn it to positive, if 0, set to default 1
      if (heightParam < 0) {
          height = heightParam * -1.0;
      } else if (heightParam == 0) {
          height = 1.0;
      } else {
          height = heightParam;
      }
    }

    /**
     * Sets the Cylinder's height based on the user's input.
     */
    void setHeight(double heightParam) {
      //If input is negative, turn it to positive, if 0, set to default 1
      if (heightParam < 0) {
          height = heightParam * -1.0;
      } else if (heightParam == 0) {
          height = 1.0;
      } else {
          height = heightParam;
      }
    }

    /**
     * Returns the radius of the circle.
     */
    double getHeight() const {
      return height;
    }

    /**
     * Calculates and returns the surface area of the cylinder.
     */
    double area() {
      return (2 * PI * radius * height) + (2 * PI * radius * radius);
    }

    /**
     * Calculates and returns the volume of the cylinder.
     */
    double volume() {
      return PI * radius * radius * height;
    }

  /*
  Protected variables and functions cannot be accessed outside
  the class definition, i.e. they can't be used in main(). Although
  they are accessible by inherent classes.
  */
  protected:
    // protected data member
    double height;

};

int main() {

  cout << "Test Circle class default constructor and area() function:" << endl;
  Circle circle1;

  cout << "Circle circle1: radius = " << circle1.getRadius() << endl;
  cout << "area = " << circle1.area() << endl;

  cout << "\n";

  cout << "Test Circle class constructor with radius:" << endl;
  Circle circle2(-10);

  cout << "Circle circle2: radius = " << circle2.getRadius() << endl;
  cout << "Test set method, set circle2 to radius 5..." << endl;
  circle2.setRadius(5);
  cout << "radius = " << circle2.getRadius() << endl;

  cout << "\n";

  cout << "Test Cylinder class given radius and height:" << endl;
  Cylinder cylinder1(20, -30);

  cout << "Cylinder cylinder1: radius = " << cylinder1.getRadius();
  cout << "; height = " << cylinder1.getHeight() << endl;
  cout << "surface area = " << cylinder1.area() << endl;
  cout << "volume = " << cylinder1.volume() << endl;

  cout << "\n";

  cout << "Test set method, set cylinder1 to radius 40 and height 50..." << endl;
  cylinder1.setRadius(40);
  cylinder1.setHeight(50);
  cout << "radius = " << cylinder1.getRadius() << "; height = " << cylinder1.getHeight() << endl;
  cout << "surface area = " << cylinder1.area() << endl;
  cout << "volume = " << cylinder1.volume() << endl;

  return 0;
}