import element.*;
import java.util.Random;

public class Functions
{
    public static int rand(int low, int high, Random gen)
    // pre: low <= high
    // post: returns uniformly random value v, low <= v <= high
    {
        return (Math.abs(gen.nextInt())%(high-low+1))+low;
    }

    public static int square(int n)
    // post: returns the square of the value n
    {
        return n*n;
    }

    public static int sumOfSquares(int n)
    // pre: n >= 0
    // post: returns the sum of squares of values between 0 and n
    {
        int sum = 0;  // intermediate result
        int i;
        for (i = 1; i <= n; i++)
        {
            sum = sum + square(i); // calls our square function
        }
        return sum;
    }
    
    public static Pt opposite(DrawingWindow d, Pt p)
    // pre: p is a valid point, d a valid window
    // post: returns the point that is opposite of p in d
    {
        int windowRight = d.bounds().right();
        int windowBottom = d.bounds().bottom();
        Pt oppositeP = new Pt(windowRight-p.x(), windowBottom-p.y());
        return oppositeP;
    }

    public static void mirror()
    {
        DrawingWindow d = new DrawingWindow();
        d.awaitMousePress();    // drawing starts with mouse press

        Pt current, next;               // points

        current = d.getMouse();         // initial location
        while (d.mousePressed())
        {
            next = d.getMouse();        // get next mouse position
            d.moveTo(current);          // draw the "right" image
            d.lineTo(next);

            d.moveTo(opposite(d,current)); // draw mirrored segment
            d.lineTo(opposite(d,next));
            current = next;
        }
    }


    public static void main(String args[])
    {
        ConsoleWindow c = new ConsoleWindow();
        DrawingWindow d = new DrawingWindow();
        int i, count=0;
        Random gen;

        c.out.println("Square of 3 is (9?): "+square(3));
        c.out.println("Sum of squares from 1 to 10 is (?): "+sumOfSquares(10));

        Pt p = new Pt(50,70);
        c.out.println("Point opposite of point "+p+" is "+opposite(d,p));

        gen = new Random();
        for (i = 0; i < 1000; i++)
        {
            if (rand(42,141,gen) == 42) count++;
        }
        c.out.println(count*100.0/1000.0+"% of 100 sided die roles are zero.");

        mirror();
        System.exit(0);
    }


}