import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
import javafx.scene.text.*;
import javafx.scene.canvas.*;
import javafx.scene.paint.Color;

/**
 * This program displays 25 copies of a message.  The color and 
 * position of each message is selected at random.  The font
 * of each message is randomly chosen from among five possible
 * fonts.  The messages are displayed on a white background.
 * There is a button that the user can click to redraw the
 * image using new random values.
 */
public class RandomStrings extends Application {

    private final static String MESSAGE = "Hello JavaFX"; 

    private Font font1, font2, font3, font4, font5;  // The five fonts.
    
    private Canvas canvas;  // The canvas on which the strings are drawn.
    

    public static void main(String[] args) {
        launch(args);
    }
    

    public void start( Stage stage ) {

        font1 = Font.font("Times New Roman", FontWeight.BOLD, 20);
        font2 = Font.font("Arial", FontWeight.BOLD, FontPosture.ITALIC, 28);
        font3 = Font.font("Verdana", 32);
        font4 = Font.font(40);
        font5 = Font.font("Times New Roman", FontWeight.BOLD, FontPosture.ITALIC, 60);
        
        canvas = new Canvas(500,300);
        draw();  // draw content of canvas the first time.

        Button redraw = new Button("Redraw!");
        redraw.setOnAction( e -> draw() );

        StackPane bottom = new StackPane(redraw);
        bottom.setStyle("-fx-background-color: gray; -fx-padding:5px;" + 
                            " -fx-border-color:black; -fx-border-width: 2px 0 0 0");
        BorderPane root = new BorderPane(canvas);
        root.setBottom(bottom);
        root.setStyle("-fx-border-color:black; -fx-border-width: 2px");
        
        stage.setScene( new Scene(root, Color.BLACK) );
        stage.setTitle("Random Strings");
        stage.setResizable(false);
        stage.show();
    }
    

    /**
     * The draw() method is responsible for drawing the content of the canvas.
     * It draws 25 copies of the message string, using a random color, font, and
     * position for each string.
     */
    private void draw() {

        GraphicsContext g = canvas.getGraphicsContext2D();
        
        double width = canvas.getWidth();
        double height = canvas.getHeight();
        
        g.setFill( Color.WHITE );  // fill with white background
        g.fillRect(0, 0, width, height);

        for (int i = 0; i < 25; i++) {

            // Draw one string.  First, set the font to be one of the five
            // available fonts, at random.  

            int fontNum = (int)(5*Math.random()) + 1;
            switch (fontNum) {
            case 1:
                g.setFont(font1);
                break;
            case 2:
                g.setFont(font2);
                break;
            case 3:
                g.setFont(font3);
                break;
            case 4:
                g.setFont(font4);
                break;
            case 5:
                g.setFont(font5);
                break;
            } // end switch

            // Set the color to a bright, saturated color, with random hue.

            double hue = 360*Math.random();
            g.setFill( Color.hsb(hue, 1.0, 1.0) );

            // Select the position of the string, at random.

            double x,y;
            x = -50 + Math.random()*(width+40);
            y = Math.random()*(height+20);

            // Draw the message.

            g.fillText(MESSAGE,x,y);
            
            // Also stroke the outline of the strings with black
            
            g.setStroke(Color.BLACK);
            g.strokeText(MESSAGE,x,y);

        } // end for

    } // end draw()


}  // end class RandomStrings
