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package ztp2;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Piotr Biskup
 */
public class Ellipsoid extends HttpServlet {


     private class Deffect {
         private double x;
         private double y;
         private double z;
         private double r;

        public Deffect(double x, double y, double z, double r) {
            this.x = x;
            this.y = y;
            this.z = z;
            this.r = r;
        }

        public boolean pointInsideSphere(double xp, double yp, double zp){

            if(  ((xp-x)*(xp-x) + (yp-y)*(yp-y) + (zp-z)*(zp-z)) <= r*r ) return true;

            return false;
        }

    }



     private List<Deffect> deffects = new ArrayList<>();
     private double a;
     private double b;
     private double c;
     private double v;
     private double g;
     private static final int points = 10_000_000;
     private int pointInsideDeffects;
     private double realMass;


    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code>
     * methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try (PrintWriter out = response.getWriter()) {
           out.println(realMass);
        }

        pointInsideDeffects = 0;
        deffects.clear();
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        double x = Double.parseDouble(request.getParameter("x"));
        double y = Double.parseDouble(request.getParameter("y"));
        double z = Double.parseDouble(request.getParameter("z"));
        double r = Double.parseDouble(request.getParameter("r"));

        Deffect d = new Deffect(x,y,z,r);

        deffects.add(d);
        //processRequest(request, response);
    }

    /**
     * Handles the HTTP <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        a = Double.parseDouble(request.getParameter("a"));
        b = Double.parseDouble(request.getParameter("b"));
        c = Double.parseDouble(request.getParameter("c"));
        v = Double.parseDouble(request.getParameter("v"));
        g = Double.parseDouble(request.getParameter("g"));


         pointInsideDeffects =  monteCarlo(points);

         double ellipsoideMass = v*(1.0 - (double)pointInsideDeffects/(double)points)*ellipsoideVolume();
         double deffectsMass = g*( (double)pointInsideDeffects/(double)points)*ellipsoideVolume();


         realMass = ellipsoideMass + deffectsMass;

        processRequest(request, response);
    }




    private boolean pointInsideEllipsoide(double xp, double yp, double zp){

            if( ((xp*xp)/(a*a) + (yp*yp)/(b*b) + (zp*zp)/(c*c)) <= 1.0 ) return true;

            return false;
        }

    private double generateVariable(double axis){
        Random random = new Random();
        int minus = random.nextInt(2);
        double a = random.nextDouble()*axis;
        if(minus == 1) a=a*(-1.0);
        return a;
    }

    private int monteCarlo(int n){

        int  insidePoints = 0;

         for(int i =0;i<n; i++){

            double x = generateVariable(a);
            double y = generateVariable(b);
            double z = generateVariable(c);

            if(!pointInsideEllipsoide(x, y, z))
                i--;
            else{
                for(Deffect d: deffects){
                    if(d.pointInsideSphere(x, y, z))
                    {
                        insidePoints++;
                        break;
                    }
                }
            }


        }

         return  insidePoints;
    }

    private double ellipsoideVolume(){
        return (4.0/3.0)*Math.PI*a*b*c;
    }

}