import objectdraw.*;
import java.awt.*;

/**
 * A recursive broccoli object that gradually grows.
 */
public class GrowingBroccoli extends ActiveObject {

    // pause between each growth of the broccoli
    private static final int PAUSE_TIME = 25;

    // dark green color for broccoli
    private static final Color BROCCOLI_COLOR = new Color(0, 135, 0);

    // diameter of broccoli bud
    private static final int BUD_SIZE = 3;
    
    // determines the angle between adjacent branches
    private static final double BRANCH_ANGLE_INC = Math.PI / 9.0;

    // Below this size draw flower
    private static final double SIZE_SMALLEST_BRANCH = 25.0;

    // How much broccoli shrinks each call
    private final static double SHRINK_FACTOR = 0.75;

    // stem of broccoli
    private AngLine stem;

    // branches of broccoli
    private GrowingBroccoli leftBranch, centerBranch, rightBranch;

    // canvas to draw objects
    private DrawingCanvas canvas;

    // size of stem
    private double stemLength; 

    // angle of stem with positive x-axis
    private double stemAngle;   

    // Draw broccoli by recursively drawing branches (and flower)
    public GrowingBroccoli(Location startLocation, double stemLength,
            double stemAngle, DrawingCanvas canvas) {

        this.stemLength = stemLength;
        this.stemAngle = stemAngle;
        this.canvas = canvas;
               
        // draw initial stem (of starting length 1)
        stem = new AngLine(startLocation, 1, stemAngle, canvas);
        stem.setColor(BROCCOLI_COLOR);
  
        start();
    }

    // recursively draw new BroccoliBranches or flowers according to the length
    // of the current branch
    public void run() {
        
        // calculate the x and y steps for each step of the animation
        Location start = stem.getStart();
        Location end = stem.getEnd();
        double xStep = end.getX() - start.getX();
        double yStep = end.getY() - start.getY();

        while (start.distanceTo(stem.getEnd()) < stemLength) {
            
            // grow the stem
            Location curEnd = stem.getEnd();
            Location newEnd = new Location(curEnd.getX() + xStep, curEnd.getY() + yStep);
            stem.setEnd(newEnd);
            pause(PAUSE_TIME);
            
        }

        if (stemLength > SIZE_SMALLEST_BRANCH) {
            
            // draw more branches
            leftBranch = new GrowingBroccoli(stem.getEnd(), stemLength * SHRINK_FACTOR,
                stemAngle + BRANCH_ANGLE_INC, canvas);
            centerBranch = new GrowingBroccoli(stem.getEnd(), stemLength * SHRINK_FACTOR,
                stemAngle, canvas);
            rightBranch = new GrowingBroccoli(stem.getEnd(), stemLength * SHRINK_FACTOR,
                stemAngle - BRANCH_ANGLE_INC, canvas);
                
        } else {
            
            // broccoli 'leaf', draw a yellow bud
            FilledOval bud = new FilledOval(stem.getEnd(), BUD_SIZE, BUD_SIZE, canvas);
            bud.setColor(Color.YELLOW);
            
        }

    }

}