import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.font.TextLayout;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.text.DateFormat;
import java.util.Date;

import javax.imageio.ImageIO;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.Timer;


/**
 * @author Donald Yessick
 *
 **/
@SuppressWarnings("serial")
public class Lab8 extends JComponent {   
	/**
	 * main is the driver for our program
	 * @param args not used
	 **/
    public static void main(String[] args) {
    	Lab8 labComponent = new Lab8();
    	labComponent.getWindow().setVisible(true);
    	labComponent.timer.start();
    }
	/**
	 * getWindow is a helper to keep main clean and simple
	 * handles the details of creating a window
	 * for our JComponent
	 * @returns a window with our component
	 **/
	private JFrame getWindow() {
		//this is the lab8 object
	    JFrame window = new JFrame(this.toString());
	    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	    window.setSize(	this.getToolkit().getScreenSize());
	    window.setContentPane(this);
	    return window;
	}
	/**
	 *  toString is predefined but not very usefully 
	 *  @return a string representing this object
	 **/
	public String toString(){
		return "lab 8";
	}
	/**
	 * paintComponent renders the JComponent to the window
	 * @param Graphics
	 **/
    public void paintComponent(Graphics oldGraphics) {
    	Graphics2D g = (Graphics2D) oldGraphics;
    	
    	g.setBackground(Color.ORANGE );
    	g.clearRect(50,50,this.getWidth()-100, this.getHeight()-100);
        String dateToday = DateFormat.getDateInstance(DateFormat.SHORT).format(new Date());
       	g.setBackground(Color.BLACK );
    	g.clearRect(50, this.getHeight()-150,this.getWidth()-100, 100);
        g.setColor(Color.ORANGE);
        g.setFont(new Font("Lucida Bright", Font.BOLD+Font.ITALIC, 24));
        this.printCenterCaption(g, dateToday);   
        g.transform(linearMapping);		//rotation magic
    	paintCenterURLImage(g, "http://dyessick.com/Coastal/images/don_simpson.png");       
    }
	/**
	 * paintURLImage is a helper function that paints an image. 
	 * This method has some nastiness to it. putting it all in
	 * paintComponent would simply make that method nasty too. 
	 * @param g Graphics2D on which to draw the image
	 * @param stringURL universal resource locator for image
	 */
	BufferedImage simpsonize = null;
    private void paintCenterURLImage(Graphics2D g, String stringURL) {
		URL url;
		if (simpsonize == null){
			try {
				url = new URL(stringURL);
				simpsonize = ImageIO.read(url);			
			} catch (MalformedURLException badUrl) {
				badUrl.printStackTrace();
	    		System.out.println("ABORTING: " + badUrl.toString());
	    		System.exit(0);
			} catch (IOException ioError) {
				ioError.printStackTrace();
	    		System.out.println("ABORTING: " + ioError.toString());
	    		System.exit(0);
			} catch (Exception otherError) {//this alone is sufficient 
				otherError.printStackTrace();
	    		System.out.println("ABORTING: " + otherError.toString());
	    		System.exit(0);
	    	}
    	}
		int imageWidth = simpsonize.getWidth();
		int imageHeight = simpsonize.getHeight();
		int screenWidth = this.getWidth();
		int screenHeight = this.getHeight();
		int xCenter = screenWidth/2;
		int yCenter = screenHeight/2;
		int xTopLeft = xCenter - imageWidth/2;
		int yTopLeft = yCenter - imageHeight/2;
		int xBottomRight = xTopLeft+imageWidth;
		int yBottomRight = yTopLeft+imageHeight;
		g.drawImage(	//scales and draws image on the fly
				simpsonize, 				//the image
				xTopLeft, yTopLeft,			//top left coordinate to place image
				xBottomRight,yBottomRight,  //bottom right coordinate to scale image
				0, 0, 						//where to start in the image --you can choose part of the image
				imageWidth,imageHeight,     //where to end in the image --you can choose part of the image
				null,						//transparent fill color, e.g. Color.YELLOW, leave as null, or omit to leave transparent
				null);						//ImageObserver -- null will do -- can be used to alert when finished
    }
    /**
     * centerString draws a string centered at the bottom of the window
     * @param g Graphics2D on which to draw the text
     * @param text String to draw
     */
    private void printCenterCaption(Graphics2D g, String text)
    {
    	TextLayout graphicRep;
    	graphicRep = new TextLayout(text, g.getFont(), g.getFontRenderContext());
    	int winWidth = this.getWidth();
    	int winHeight = this.getHeight()-50 ;//50 is my bottom border
    	int txtWidth = graphicRep.getBounds().getBounds().width; //I know, I know, "getBounds().getBounds()" it is ridiculous
    	int txtHeight = graphicRep.getBounds().getBounds().height;//but other methods were no less clean (the first getBounds is type double)
    	graphicRep.draw(g, winWidth/2-txtWidth/2, (winHeight)-(100-txtHeight)/2); //the space is 100 high 
    }
    /**
     * The AffineTransform class represents a 2D affine transform that performs a linear mapping from 2D coordinates to other 2D coordinates 
     * that preserves the "straightness" and "parallelness" of lines. Affine transformations can be constructed using sequences of 
     * translations, scales, flips, rotations, and shears. 
     * 
     * Such a coordinate transformation can be represented by a 3 row by 3 column matrix with an implied last row of [ 0 0 1 ]. 
     * This matrix transforms source coordinates (x,y) into destination coordinates (x',y') by considering them to be a column vector 
     * and multiplying the coordinate vector by the matrix according to the following process: 

        [ x']   [  m00  m01  m02  ] [ x ]   [ m00x + m01y + m02 ]
        [ y'] = [  m10  m11  m12  ] [ y ] = [ m10x + m11y + m12 ]
        [ 1 ]   [   0    0    1   ] [ 1 ]   [         1         

     */
    private AffineTransform linearMapping = new AffineTransform();//will store the rotation transform   
    /**
     * timer forces repainting (with new rotation) every 15000 milliseconds (15 seconds))
     * this is syntactically ugly so don't get hung up on it
     * key idea, repaint(), forces the screen to repaint
     */
    protected Timer timer = new Timer(500, new ActionListener(){
    	public void actionPerformed(ActionEvent time){
    		linearMapping.rotate(Math.PI/180*3.14, getWidth()/2, getHeight()/2); //rotates linearMapping 3.14 degrees (in radians)
    		repaint();
    	}});
}