import javafx.application.Application;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.scene.layout.Pane;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;

/**
 * This program demonstrates how to do your own layout.  The root container
 * for the screen is a Pane, which will resize its children to their
 * preferred size, but will not set their location.  This program does
 * not do anything useful.
 *
 * The program sets the locations of a canvas that shows a checkerboard
 * and a label.  The Pane will set the size of the label.  Since a canvas
 * is not resizable, it is simply shown at its natural size.  Two
 * buttons are also shown.  They are set to be "unmanaged" which stops
 * any container from setting their size and positions.  This makes it
 * possible to set the size of the buttons as well as their locations.
 */

public class OwnLayoutDemo extends Application {

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

    //-------------------------------------------------------------------------

    Checkerboard board;  // A canvas on which a checker board is drawn,
                         // defined by a static nested subclass.

    Button resignButton;      // Two buttons.
    Button newGameButton;

    Label message;   // A label for displaying messages to the user.

    int clickCount;   // Counts how many times the button was clicked.


    /**
     * The start method uses a Pane as a root node of the scene.  The preferred
     * size of the Pane is set explicitly to 500-by-420; the stage will take its
     * size from the preferred size of the Pane.  Four child nodes are added to
     * the Pane.  The location of each child is set, and sizes are set for
     * two buttons.  The buttons are set to be unmanaged to stop the Pane
     * from setting their sizes.  (Without the preferred size for the Pane,
     * it would be just large enough to show the checkerboard and the label,
     * but not the buttons, which it ignores.)
     */
    public void start(Stage stage) {

        /* Create the child nodes. */

        board = new Checkerboard(); // a subclass of Canvas, defined below
        board.draw();  // draws the content of the checkerboard

        newGameButton = new Button("New Game");
        newGameButton.setOnAction( e -> doNewGame() );

        resignButton = new Button("Resign");
        resignButton.setOnAction( e -> doResign() );

        message = new Label("Click \"New Game\" to begin.");
        message.setTextFill( Color.rgb(100,255,100) ); // Light green.
        message.setFont( Font.font(null, FontWeight.BOLD, 18) );

        /* Set the location of each child by calling its relocate() method */

        board.relocate(20,20);
        newGameButton.relocate(370, 120);
        resignButton.relocate(370, 200);
        message.relocate(20, 370);
        
        /* Set the sizes of the buttons.  For this to have an effect, make
         * the butons "unmanaged."  If they are managed, the Pane will set
         * their sizes. */
        
        resignButton.setManaged(false);
        resignButton.resize(100,30);
        newGameButton.setManaged(false);
        newGameButton.resize(100,30);
        
        /* Create the Pane and give it a preferred size. */
        
        Pane root = new Pane();
        
        root.setPrefWidth(500);
        root.setPrefHeight(420);
        
        /* Add the child nodes to the Pane and set up the rest of the GUI */

        root.getChildren().addAll(board, newGameButton, resignButton, message);
        root.setStyle("-fx-background-color: darkgreen; -fx-border-color: darkred; -fx-border-width:3");
        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.setTitle("Doing your own layout");
        stage.show();

    } // end start()

    
    /**
     * A method to be called when the user clicks "New Game"
     */
    private void doNewGame() {
        clickCount++;
        if (clickCount == 1)
            message.setText("First click:  \"New Game\" was clicked.");
        else
            message.setText("Click no. " + clickCount + ":  \"New Game\" was clicked."); 
    }
    
    
    /**
     * A method to be called when the user clicks "Resign"
     */
    private void doResign() {
        clickCount++;
        if (clickCount == 1)
            message.setText("First click:  \"Resign\" was clicked.");
        else
            message.setText("Click no. " + clickCount + ":  \"Resign\" was clicked."); 
    }


    /**
     * This canvas displays a 320-by-320 checkerboard pattern with
     * a 2-pixel dark red border.  The canvas will be exactly
     * 324-by-324 pixels.
     */
    private static class Checkerboard extends Canvas {

        public Checkerboard() {
            super(324,324); // Call constructor from Canvas class to set the size.
        }

        /**
         * Draws the content of the canvas.
         */
        public void draw() {
            
            GraphicsContext g = getGraphicsContext2D();

            // Draw a 2-pixel dark red border around the edges of the board.

            g.setStroke(Color.DARKRED);
            g.setLineWidth(2);
            g.strokeRect( 1, 1, 322, 322 );

            // Draw  checkerboard pattern in gray and lightGray.

            for (int row = 0; row < 8; row++) {
                for (int col = 0; col < 8; col++) {
                    if ( row % 2 == col % 2 )
                        g.setFill(Color.LIGHTGRAY);
                    else
                        g.setFill(Color.GRAY);
                    g.fillRect(2 + col*40, 2 + row*40, 40, 40);
                }
            }
            
        }
        
    } // end nested class Checkerboard


} // end class OwnLayoutDemo