/*
 * [SnapTime.java]
 *
 * Summary: A stopwotch variant.
 *
 * Copyright: (c) 2016-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.0 2016-06-16 initial version
 */
package com.mindprod.snaptime;

import com.mindprod.common18.Build;
import com.mindprod.common18.CMPAboutJBox;
import com.mindprod.common18.FontFactory;
import com.mindprod.common18.HybridJ;
import com.mindprod.common18.JEButton;
import com.mindprod.common18.Laf;
import com.mindprod.common18.VersionCheck;

import javax.swing.JApplet;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.SimpleDateFormat;
import java.util.GregorianCalendar;
import java.util.TimeZone;
import java.util.Timer;
import java.util.TimerTask;

/**
 * A stopwotch variant.
 * <p/>
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.0 2016-06-16 initial version
 * @noinspection FieldCanBeLocal
 * @since 2016-06-16
 */
public final class SnapTime extends JApplet implements ActionListener, ChangeListener
    {
    /**
     * height of Applet box in pixels. Does not include surrounding frame.
     */
    private static final int APPLET_HEIGHT = 220;

    /**
     * Width of Applet box in pixels.  Oddly displays as 286
     */
    private static final int APPLET_WIDTH = 350;

    private static final int FIRST_COPYRIGHT_YEAR = 2016;

    /**
     * copyright not displayed
     *
     * @noinspection UnusedDeclaration
     */
    private static final String EMBEDDED_COPYRIGHT =
            "Copyright: (c) 2016-2017 Roedy Green, Canadian Mind Products, http://mindprod.com";

    private static final String RELEASE_DATE = "2016-06-16";

    private static final String TITLE_STRING = "SnapTime";

    private static final String VERSION_STRING = "1.0";

    private static final Color BACKGROUND_FOR_APPLET = new Color( 0xfaf0e6 )/* linen */;

    private static final Color FOREGROUND_FOR_APPLET = new Color( 0x1e90ff )/* dodger blue */;

    /**
     * for titles
     */
    private static final Color FOREGROUND_FOR_TITLE = new Color( 0xdc143c );

    /**
     * for for titles and About buttons
     */
    private static final Font FONT_FOR_TITLE = FontFactory.build( "Dialog", Font.BOLD, 16 );

    /**
     * for for title second line
     */
    private static final Font FONT_FOR_TITLE2 = FontFactory.build( "Dialog", Font.PLAIN, 14 );

    /**
     * DARK_GREEN Colour.
     */
    private static final Color FOREGROUND_FOR_TEXT = new Color( 0x008000 );

    /**
     * Wedgewood blue.
     */
    private static final Color FOREGROUND_FOR_SNAPLIST = new Color( 0x5157ff );

    /**
     * Local date formatter.
     */
    private static final SimpleDateFormat FLOCAL = new SimpleDateFormat( "h:mm:ss:SSS aa" );   // aa=AM/PM

    /**
     * where lsist of time snaps are displayed
     */
    private JTextArea snaps;

    /**
     * button to request another password
     */
    private JEButton snapButton;

    /**
     * Displayed title
     */
    private JLabel title;

    /**
     * title, second line
     */
    private JLabel title2;

    /**
     * control to contain the PC's time
     */
    private JTextField pcTimeText;

    /**
     * allocate all components
     */
    private void buildComponents()
        {
        title = new JLabel( TITLE_STRING + " " + VERSION_STRING );
        title.setForeground( FOREGROUND_FOR_TITLE );
        title.setFont( FONT_FOR_TITLE );
        title2 = new JLabel(
                "released:" +
                RELEASE_DATE +
                " build:" +
                Build.BUILD_NUMBER
        );
        title2.setFont( FONT_FOR_TITLE2 );
        title2.setForeground( FOREGROUND_FOR_TITLE );
        pcTimeText = new JTextField();
        pcTimeText.setForeground( FOREGROUND_FOR_TEXT );
        pcTimeText.setEditable( false );
        pcTimeText.setHorizontalAlignment( JTextField.CENTER );
        snaps = new JTextArea( 20, 15 );
        snaps.setForeground( FOREGROUND_FOR_SNAPLIST );
        snaps.setEditable( false );
        snapButton = new JEButton( "SNAP" );
        snapButton.setToolTipText(
                "Take a snapshot of the time." );
        }

    /**
     * build a menu with Look & Feel and About across the top
     */
    private void buildMenu()
        {
        // turn on anti-alias
        System.setProperty( "swing.aatext", "true" );
        final JMenuBar menubar = new JMenuBar();
        setJMenuBar( menubar );
        final JMenu lafMenu = Laf.buildLookAndFeelMenu();
        if ( lafMenu != null )
            {
            menubar.add( lafMenu );
            }
        final JMenu menuHelp = new JMenu( "Help" );
        menubar.add( menuHelp );
        final JMenuItem aboutItem = new JMenuItem( "About" );
        menuHelp.add( aboutItem );
        aboutItem.addActionListener( e ->
        {
        // open aboutbox frame
        new CMPAboutJBox( TITLE_STRING,
                VERSION_STRING,
                "Stop watch variant.",
                "",
                "freeware",
                RELEASE_DATE,
                FIRST_COPYRIGHT_YEAR,
                "Roedy Green",
                "SNAPTIME",
                "1.8" );
        } );
        }

    /**
     * display PC local time. Used by both refresh and background updater
     */
    private void displayPCTime()
        {
        // intern to reduce garbage collection frequency
        // Avoid flicker, since can easily tell if no change.
        GregorianCalendar pcTime = new GregorianCalendar(); // get current time of day
        FLOCAL.setTimeZone( TimeZone.getDefault() );
        final String t = FLOCAL.format( pcTime.getTime() ).intern();
        // setText is thread safe, but not getText
        pcTimeText.setText( t );
        } // end displayPCTime

    /**
     * What happens after SNAP button hit.
     */
    private void hit()
        {
        displayPCTime();  // extra non-scheduled
        // add current time to the list,
        final String now = pcTimeText.getText();
        snaps.append( now + "\n" );
        }

    /**
     * Install listeners
     */
    private void installHooks()
        {
        snapButton.addActionListener( this );
        }

    /**
     * Layout components in a GridBag
     *
     * @param contentPane JApplet contentPane.
     */
    private void layoutComponents( Container contentPane )
        {
        // layout
        // ---   0-------------1--------------
        // 0---- title ------- title2---
        // 1 ----time --   --snaps----
        // 2 -----SNAP---  ------------
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( title,
                new GridBagConstraints( 0,
                        0,
                        2,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.NONE,
                        new Insets( 10, 5, 5, 5 ),
                        0,
                        0
                )
        );
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( title2,
                new GridBagConstraints( 1,
                        0,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.EAST,
                        GridBagConstraints.NONE,
                        new Insets( 10, 5, 5, 10 ),
                        0,
                        0
                )
        );
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( pcTimeText,
                new GridBagConstraints( 0,
                        1,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.HORIZONTAL,
                        new Insets( 5, 5, 5, 5 ),
                        100,
                        0 )
        );
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( new JScrollPane( snaps,
                        JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                        JScrollPane.HORIZONTAL_SCROLLBAR_NEVER ),
                new GridBagConstraints( 1,
                        1,
                        1,
                        1,
                        0.0,
                        1.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.NONE,
                        new Insets( 5, 5, 5, 5 ),
                        100,
                        100 )
        );
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( snapButton,
                new GridBagConstraints( 0,
                        2,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.EAST,
                        GridBagConstraints.NONE,
                        new Insets( 5, 5, 10, 5 ),
                        20,
                        10
                )
        );
        }

    /**
     * set up an event to happen later
     */
    private void startClockDisplay()
        {
        // repeat
        new Timer().schedule( new ScheduleRunner(), 0, 200 /** every 200 ms */ );
        }

    /**
     * Allow JApplet to be run as an Application
     *
     * @param args not used.
     */
    public static void main( String[] args )
        {
        HybridJ.fireup( new SnapTime(),
                TITLE_STRING + " " + VERSION_STRING,
                APPLET_WIDTH,
                APPLET_HEIGHT );
        }

    /**
     * Invoked when an action occurs.
     *
     * @param e event, not used
     */
    public void actionPerformed( ActionEvent e )
        {
        hit();
        }

    /**
     * Called by the browser or Applet viewer to inform
     * this Applet that it is being reclaimed and that it should destroy
     * any resources that it has allocated.
     */
    @Override
    public void destroy()
        {
        title2 = null;
        title = null;
        }

    /**
     * Called by the browser or Applet viewer to inform
     * this Applet that it has been loaded into the system.
     */
    @Override
    public void init()
        {
        Container contentPane = this.getContentPane();
        if ( !VersionCheck.isJavaVersionOK( 1, 8, 0, contentPane ) )
            {
            // effectively abort
            return;
            }
        buildMenu(); // also initial L&F
        contentPane.setLayout( new GridBagLayout() );
        contentPane.setBackground( BACKGROUND_FOR_APPLET );
        contentPane.setForeground( FOREGROUND_FOR_APPLET );
        buildComponents();
        layoutComponents( contentPane );
        installHooks();
        startClockDisplay();
        this.validate();
        this.setVisible( true );
        }

    /**
     * Applet has scrolled onscreen.
     */
    public void start()
        {
        }

    /**
     * Invoked when the target of the listener has changed its state.
     *
     * @param e a ChangeEvent object, not used
     */
    public void stateChanged( ChangeEvent e )
        {
        hit();
        }

    /**
     * Applet scrolled offscreen
     */
    public void stop()
        {
        }

    /**
     * run method will be invoked when time is up.
     */
    private class ScheduleRunner extends TimerTask
        {
        /**
         * executed when time is up.
         */
        public void run()
            {
            displayPCTime();
            }
        } // end inner class ScheduleRunner
    }