/* 
 * A program to create a circle comprised of square, where sizes are determined by an dialog box. 
 */
package npw;

import painter.SPainter;
import shapes.SCircle;
import shapes.SSquare;

import javax.swing.*;
import java.awt.*;
import java.util.Random;
import java.util.Scanner;

public class CircleOfSquares {

    private void paintTheImage(){
        // input info
        int radius = getNumber("circle radius");
        int side = getNumber("square side length");

        SPainter painter = new SPainter("Circle of Squares", radius*2+50, radius*2+50);
        painter.setBrushWidth(3);
        SCircle circle = new SCircle(radius);
        SSquare square = new SSquare(side);

        paintCircleOfSquares(painter, circle, square);
    }
    private void paintCircleOfSquares(SPainter painter, SCircle circle, SSquare square){
        //position painter
        painter.mfd(circle.radius());
        painter.tr();
        //paint circle of squares
        double moved = 0;
        while (moved < circle.diameter()) {
            double chord = chordLength(circle.radius()-moved, circle);
            int squares = squaresOnLineCount(chord, square.side());
            paintRow(painter, square, squares);
            nextRow(painter, square.side());
            moved = moved + square.side();
        }
        //make invariant to painter position
        painter.tl();
        painter.mfd(circle.radius());
    }
    private void nextRow(SPainter painter, double rowHeight){
        painter.tr();
        painter.mfd(rowHeight);
        painter.tl();
    }
    //painter is at the center of the row to paint, facing right
    private void paintRow(SPainter painter, SSquare square, int squaresToPaint) {
        //move back 1/2 of the length we're painting to get ready to paint the row
        double centerOffset = ((squaresToPaint * square.side()) / 2) - square.side() / 2;
        painter.mbk(centerOffset);

        //paint rows
        int painted = 0;
        while (painted < squaresToPaint) {
            paintOneSquare(painter, square);
            painter.mfd(square.side());
            painted = painted + 1;
        }

        //method invariant to painter position
        painter.mbk(centerOffset + square.side());
    }
    private void paintOneSquare(SPainter painter, SSquare square){
        painter.setColor(randomColor());
        painter.paint(square);
        painter.setColor(Color.BLACK);
        painter.draw(square);
    }

    private static int squaresOnLineCount(double lineLength, double sideLength){
        int squares = ( (int)Math.ceil( ( lineLength - sideLength) / sideLength) + 1);
        return squares;
    }

    private double chordLength(double yOffest, SCircle circle){
        double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffest, 2));
        double chordLength = xLength * 2;
        return chordLength;
    }
    private static int getNumber(String prompt) {
        String nss = JOptionPane.showInputDialog(null,prompt+"?");
        Scanner scanner = new Scanner(nss);
        return scanner.nextInt();
    }

    private static Color randomColor() {
        Random rgen = new Random();
        int r = rgen.nextInt(256);
        int g = rgen.nextInt(256);
        int b = rgen.nextInt(256);
        return new Color(r,g,b);
    }

    public CircleOfSquares() {
        paintTheImage();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new CircleOfSquares();
            }
        });
    }

}