/*
 * [OfficialEncoding.java]
 *
 * Summary: Displays the official name of any alias encoding, letting your know if it is supported.
 *
 * Copyright: (c) 1996-2017 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 2007-07-06 initial release
 *  1.1 2008-04-05 add build to title.
 */
package com.mindprod.officialencoding;

import com.mindprod.common18.Build;
import com.mindprod.common18.CMPAboutJBox;
import com.mindprod.common18.Common18;
import com.mindprod.common18.FontFactory;
import com.mindprod.common18.HybridJ;
import com.mindprod.common18.JEButton;
import com.mindprod.common18.VersionCheck;

import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
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.nio.charset.Charset;

/**
 * Displays the official name of any alias encoding, letting your know if it is supported.
 * <p/>
 * It also displays some sample
 * characters available in that encoding.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.1 2008-04-05 add build to title.
 * @since 2007-07-06
 */
public final class OfficialEncoding extends JApplet
    {
    /**
     * height of Applet box in pixels. Does not include surrounding frame.
     */
    private static final int APPLET_HEIGHT = 254;

    /**
     * Width of Applet box in pixels.
     */
    private static final int APPLET_WIDTH = 636;

    private static final int FIRST_COPYRIGHT_YEAR = 1996;

    /**
     * undisplayed copyright notice
     */
    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String EMBEDDED_COPYRIGHT =
            "Copyright: (c) 1996-2017 Roedy Green, Canadian Mind Products, http://mindprod.com";

    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String RELEASE_DATE = "2008-04-05";

    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String TITLE_STRING = "Official Encoding";

    @SuppressWarnings( { "UnusedDeclaration" } )
    private static final String VERSION_STRING = "1.1";

    /**
     * background colour, pale green to match website
     */
    private static final Color BACKGROUND_FOR_BODY = Build.BACKGROUND_FOR_BLENDING;

    /**
     * instruction normal color
     */
    private static final Color FOREGROUND_FOR_INSTRUCTIONS = new Color( 0x339911 );

    /**
     * foreground colour for labels
     */
    private static final Color FOREGROUND_FOR_LABEL = new Color( 0x0000b0 );

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

    /**
     * background colour for official name.  Default grey is too dark
     */
    private static final Color UNBACKGROUND_FOR_EDITABLE = new Color( 0xf8f8f8 );

    /**
     * charset display font
     */
    private static final Font FONT_FORS =
            FontFactory.build( "Monospaced", Font.PLAIN, 12 );

    /**
     * instructions font
     */
    private static final Font FONT_FOR_INSTRUCTIONS =
            FontFactory.build( "Dialog", Font.PLAIN, 12 );

    /**
     * title font
     */
    private static final Font FONT_FOR_TITLE = FontFactory.build( "Dialog", Font.BOLD, 15 );

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

    /**
     * byte form of test pattern to display charSet
     */
    private static final byte[] byteTestPattern;

    static
        {
        final int rows = 4;
        final int cols = 64;
        byteTestPattern = new byte[ rows * ( cols + 1 ) - 1 ];
        int b = 0;
        for ( int i = 0; i < rows; i++ )
            {
            for ( int j = 0; j < cols; j++ )
                {
                byteTestPattern[ i * ( cols + 1 ) + j ] =
                        ( byte ) Math.max( 32, b++ );
                }
            }
        for ( int i = 0; i < rows - 1; i++ )
            {
            // add \n to end of rows but the last
            byteTestPattern[ i * ( cols + 1 ) + cols ] = '\n';
            }
        }

    /**
     * about button
     */
    private JButton about;

    /**
     * hit to look up encoding
     */
    private JButton okButton;

    /**
     * label for alias encoding name
     */
    private JLabel aliasLabel;

    /**
     * how to use program
     */
    private JLabel instructions;

    /**
     * label  for official encoding name
     */
    private JLabel officialLabel;

    /**
     * title
     */
    private JLabel title;

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

    /**
     * display first 256 chars
     */
    private JTextArea charSetDisplay;

    /**
     * encoding user enters
     */
    private JTextField alias;

    /**
     * official name of the encoding
     */
    private JTextField official;

    /**
     * allocate all components
     */
    private void buildComponents()
        {
        title = new JLabel( TITLE_STRING + " " + VERSION_STRING, JLabel.LEFT );
        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 );
        about = new JEButton( "About" );
        about.setToolTipText( "About " + TITLE_STRING + " " + VERSION_STRING );
        aliasLabel = new JLabel( "encoding name" );
        aliasLabel.setForeground( FOREGROUND_FOR_LABEL );
        officialLabel = new JLabel( "official encoding name" );
        officialLabel.setForeground( FOREGROUND_FOR_LABEL );
        alias = new JTextField();
        alias.setEditable( true );
        // avoid looking at restricted system property.
        String defaultEncodingName = Charset.
                defaultCharset().
                name();
        alias.setText( defaultEncodingName );
        okButton = new JEButton( "Convert" );
        okButton.setToolTipText( "Convert encoding to official name" );
        official = new JTextField();
        official.setBackground( UNBACKGROUND_FOR_EDITABLE );
        official.setEditable( false );
        charSetDisplay = new JTextArea( 16, 16 );
        charSetDisplay.setBackground( UNBACKGROUND_FOR_EDITABLE );
        charSetDisplay.setEditable( false );
        charSetDisplay.setFont( FONT_FORS );
        instructions =
                new JLabel(
                        "Enter an encoding name and click OK.  View the corresponding official equivalent.",
                        JLabel.CENTER );
        instructions.setForeground( FOREGROUND_FOR_INSTRUCTIONS );
        instructions.setFont( FONT_FOR_INSTRUCTIONS );
        }

    /**
     * look up the official name of the alias
     */
    private void getOfficialName()
        {
        try
            {
            final String canonicalName =
                    Charset.forName( alias.getText().trim() ).name();
            official.setText( canonicalName );
            charSetDisplay.setText( new String( byteTestPattern,
                    canonicalName ) );
            }
        catch ( Exception exception )
            {
            official.setText( "not supported" );
            }
        }

    /**
     * register listeners
     */
    private void hookComponents()
        {
        about.addActionListener( new ActionListener()
            {
            public void actionPerformed( ActionEvent e )
                {
                // open aboutbox frame
                new CMPAboutJBox( TITLE_STRING,
                        VERSION_STRING,
                        "Looks up the official name of an encoding.",
                        "",
                        "freeware",
                        RELEASE_DATE,
                        FIRST_COPYRIGHT_YEAR,
                        "Roedy Green",
                        "OFFICIALENCODING",
                        "1.8" );
                }
            } );
        okButton.addActionListener( new ActionListener()
            {
            public void actionPerformed( ActionEvent e )
                {
                getOfficialName();
                }
            } );
        // trigger also if hits enter
        alias.addActionListener( new ActionListener()
            {
            public void actionPerformed( ActionEvent e )
                {
                getOfficialName();
                }
            } );
        }

    /**
     * layout
     *
     * @param contentPane JApplet contentPage
     */
    private void layoutComponents( Container contentPane )
        {
        // --0----------1-------2-----3--
        // 0 title----- --title2---  about
        // 1 "encoding"  "official"------
        // 2 encoding ok  official--------
        // 3 --- instructions -----------
        // x y w h wtx wty anchor fill T L B R padx pady
        contentPane.add( title,
                new GridBagConstraints( 0,
                        0,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.NONE,
                        new Insets( 10, 10, 5, 5 ),
                        0,
                        0 )
        );
        contentPane.add( title2,
                new GridBagConstraints( 1,
                        0,
                        2,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.NONE,
                        new Insets( 10, 5, 5, 5 ),
                        0,
                        0 )
        );
        contentPane.add( about,
                new GridBagConstraints( 3,
                        0,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.EAST,
                        GridBagConstraints.NONE,
                        new Insets( 10, 5, 5, 10 ),
                        0,
                        0 )
        );
        contentPane.add( aliasLabel,
                new GridBagConstraints( 0,
                        1,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.NONE,
                        new Insets( 0, 10, 0, 10 ),
                        0,
                        0 )
        );
        contentPane.add( officialLabel,
                new GridBagConstraints( 3,
                        1,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.EAST,
                        GridBagConstraints.NONE,
                        new Insets( 0, 10, 0, 10 ),
                        0,
                        0 )
        );
        contentPane.add( alias,
                new GridBagConstraints( 0,
                        2,
                        1,
                        1,
                        50.0,
                        0.0,
                        GridBagConstraints.WEST,
                        GridBagConstraints.HORIZONTAL,
                        new Insets( 5, 10, 5, 10 ),
                        0,
                        0 )
        );
        contentPane.add( okButton,
                new GridBagConstraints( 1,
                        2,
                        1,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.CENTER,
                        GridBagConstraints.NONE,
                        new Insets( 5, 10, 5, 10 ),
                        0,
                        0 )
        );
        contentPane.add( official,
                new GridBagConstraints( 2,
                        2,
                        2,
                        1,
                        50.0,
                        0.0,
                        GridBagConstraints.EAST,
                        GridBagConstraints.HORIZONTAL,
                        new Insets( 5, 10, 5, 10 ),
                        0,
                        0 )
        );
        contentPane.add( charSetDisplay,
                new GridBagConstraints( 0,
                        3,
                        4,
                        1,
                        0.0,
                        100.0,
                        GridBagConstraints.CENTER,
                        GridBagConstraints.BOTH,
                        new Insets( 0, 10, 5, 10 ),
                        0,
                        0 )
        );
        contentPane.add( instructions,
                new GridBagConstraints( 0,
                        4,
                        4,
                        1,
                        0.0,
                        0.0,
                        GridBagConstraints.CENTER,
                        GridBagConstraints.BOTH,
                        new Insets( 0, 10, 10, 10 ),
                        0,
                        0 )
        );
        }

    /**
     * Allow this Applet to run as an application as well.
     *
     * @param args command line arguments ignored.
     */
    public static void main( String args[] )
        {
        HybridJ.fireup( new OfficialEncoding(),
                TITLE_STRING + " " + VERSION_STRING
                /* too narrow for usual title */,
                APPLET_WIDTH,
                APPLET_HEIGHT );
        } // end main

    /**
     * Called by the browser or Applet viewer to inform
     * this Applet that it has been loaded into the system.
     */
    @Override
    public void init()
        {
        // use JDK 1.5 so can do unsigned lookup of default encoding.
        if ( !VersionCheck.isJavaVersionOK( 1, 8, 0, this ) )
            {
            return;
            }
        Common18.setLaf();
        Container contentPane = this.getContentPane();
        contentPane.setLayout( new GridBagLayout() );
        contentPane.setBackground( BACKGROUND_FOR_BODY );
        buildComponents();
        layoutComponents( contentPane );
        hookComponents();
        getOfficialName();
        this.validate();
        this.setVisible( true );
        }
    }