/**
 *                    BioJava development code
 *
 * This code may be freely distributed and modified under the
 * terms of the GNU Lesser General Public Licence.  This should
 * be distributed with the code.  If you do not have a copy,
 * see:
 *
 *      http://www.gnu.org/copyleft/lesser.html
 *
 * Copyright for this code is held jointly by the individual
 * authors.  These should be listed in @author doc comments.
 *
 * For more information on the BioJava project and its aims,
 * or to join the biojava-l mailing list, visit the home page
 * at:
 *
 *      http://www.biojava.org/
 *
 * Created on Sep 14, 2011
 * Created by Andreas Prlic
 *
 * @since 3.0.2
 */
package org.biojava.nbio.structure.align.gui.autosuggest;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Vector;
import java.util.concurrent.atomic.AtomicBoolean;




/** A JTextField that can make suggestions for auto-complete.
 *
 * @author Andreas Prlic
 *
 */
public class JAutoSuggest extends JTextField{

        /**
         *
         */
        private static final long serialVersionUID = 8591734727984365156L;

        private static final String DEFAULT_TEXT= "Please enter text ...";

        String defaultText;
        private JDialog dialog;
        private Point location;
        private JList list;

        private Vector<String> suggestions;

        /** last word that was entered by user */
        private String lastWord ;

        AutoSuggestProvider autoSuggestProvider;

        Font regular;
        Font busy;

        SuggestionFetcher matcher;

        public JAutoSuggest(){
                super();

                init();
        }

        public JAutoSuggest(int size){
                super(size);
                init();
        }

        public JAutoSuggest(Frame owner){
                owner.addComponentListener(new ComponentListener() {
                        @Override
                        public void componentShown(ComponentEvent e) {
                                updateLocation();
                        }

                        @Override
                        public void componentResized(ComponentEvent e) {
                                updateLocation();
                        }

                        @Override
                        public void componentMoved(ComponentEvent e) {
                                updateLocation();
                        }

                        @Override
                        public void componentHidden(ComponentEvent e) {
                                updateLocation();
                        }
                });
                owner.addWindowListener(new WindowListener() {
                        @Override
                        public void windowOpened(WindowEvent e) {
                        }

                        @Override
                        public void windowIconified(WindowEvent e) {
                                dialog.setVisible(false);
                        }

                        @Override
                        public void windowDeiconified(WindowEvent e) {
                        }

                        @Override
                        public void windowDeactivated(WindowEvent e) {
                        }

                        @Override
                        public void windowClosing(WindowEvent e) {
                                dialog.dispose();
                        }

                        @Override
                        public void windowClosed(WindowEvent e) {
                                dialog.dispose();
                        }

                        @Override
                        public void windowActivated(WindowEvent e) {
                        }
                });
                addFocusListener(new FocusListener() {
                        @Override
                        public void focusLost(FocusEvent e) {
                                System.out.println("Lost Focus");
                                dialog.setVisible(false);

                                if (getText().trim().equals("") && e.getOppositeComponent() != null && e.getOppositeComponent().getName() != null) {
                                        if (!e.getOppositeComponent().getName().equals("suggestFieldDropdownButton")) {
                                                setText(defaultText);
                                        }
                                } else if (getText().trim().equals("")) {
                                        setText(defaultText);
                                }
                        }

                        @Override
                        public void focusGained(FocusEvent e) {
                                System.out.println("Lost Gained");
                                if (getText().trim().equals(defaultText)) {
                                        setText("");
                                }

                                showSuggest();
                        }
                });




                init();

                // set dialog owner...
                //dialog.setD

        }


        private void initSuggestionList() {
                list = new JList();
                list.addMouseListener(new MouseListener() {
                        private int selected;

                        @Override
                        public void mousePressed(MouseEvent e) {
                        }

                        @Override
                        public void mouseReleased(MouseEvent e) {
                                if (selected == list.getSelectedIndex()) {
                                        // provide double-click for selecting a suggestion
                                        setText((String) list.getSelectedValue());

                                        dialog.setVisible(false);
                                }
                                selected = list.getSelectedIndex();
                        }

                        @Override
                        public void mouseExited(MouseEvent e) {
                        }

                        @Override
                        public void mouseEntered(MouseEvent e) {
                        }

                        @Override
                        public void mouseClicked(MouseEvent e) {
                        }
                });
                dialog.add(new JScrollPane(list, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                                JScrollPane.HORIZONTAL_SCROLLBAR_NEVER));
                dialog.pack();
                addKeyListener(new KeyListener() {
                        @Override
                        public void keyTyped(KeyEvent e) {
                        }

                        @Override
                        public void keyPressed(KeyEvent e) {
                                updateLocation();
                        }

                        @Override
                        public void keyReleased(KeyEvent e) {
                                if (e.getKeyCode() == KeyEvent.VK_ESCAPE) {
                                        dialog.setVisible(false);
                                        return;
                                } else if (e.getKeyCode() == KeyEvent.VK_DOWN) {
                                        if (dialog.isVisible()) {
                                                list.setSelectedIndex(list.getSelectedIndex() + 1);
                                                list.ensureIndexIsVisible(list.getSelectedIndex() + 1);
                                                return;
                                        } else {
                                                showSuggest();
                                        }
                                } else if (e.getKeyCode() == KeyEvent.VK_UP) {
                                        list.setSelectedIndex(list.getSelectedIndex() - 1);
                                        list.ensureIndexIsVisible(list.getSelectedIndex() - 1);
                                        return;
                                } else if (e.getKeyCode() == KeyEvent.VK_ENTER
                                                && list.getSelectedIndex() != -1 && suggestions.size() > 0) {
                                        setText((String) list.getSelectedValue());


                                        dialog.setVisible(false);
                                        return;
                                }
                                showSuggest();
                        }
                });

        }

        private void init(){
                autoSuggestProvider =  new DefaultAutoSuggestProvider();
                lastWord = "";
                regular = getFont();
                busy = new Font(getFont().getName(), Font.ITALIC, getFont().getSize());
                suggestions = new Vector<String>();
                defaultText = DEFAULT_TEXT;


                dialog = new JDialog();
                dialog.setUndecorated(true);
                dialog.setFocusableWindowState(false);
                dialog.setFocusable(false);

                initSuggestionList();
        }

        public String getDefaultText() {
                return defaultText;
        }

        public void setDefaultText(String defaultText) {
                this.defaultText = defaultText;
        }

        public AutoSuggestProvider getAutoSuggestProvider() {
                return autoSuggestProvider;
        }

        public void setAutoSuggestProvider(AutoSuggestProvider autoSuggestProvider) {
                this.autoSuggestProvider = autoSuggestProvider;
        }

        /**
         * Force the suggestions to be displayed (Useful for buttons
         * e.g. for using JSuggestionField like a ComboBox)
         */
        public void showSuggest() {

                assert(getText() != null);
                lastWord = getText().trim();
                        //autoSuggestProvider.getSuggestion(lastWord);



                if (!getText().toLowerCase().contains(lastWord.toLowerCase())) {
                        suggestions.clear();
                }

                if (matcher != null) {
                        matcher.setStop();
                }
                matcher = new SuggestionFetcher();

                //SwingUtilities.invokeLater(matcher);
                matcher.execute();
                lastWord = getText().trim();
                updateLocation();
        }

        /**
         * Force the suggestions to be hidden (Useful for buttons, e.g. to use
         * JSuggestionField like a ComboBox)
         */
        public void hideSuggest() {
                dialog.setVisible(false);
        }

        /**
         * @return boolean Visibility of the suggestion window
         */
        public boolean isSuggestVisible() {
                return dialog.isVisible();
        }



        /**
         * Place the suggestion window under the JTextField.
         */
        private void updateLocation() {
                try {
                        location = getLocationOnScreen();
                        location.y += getHeight();
                        dialog.setLocation(location);
                } catch (IllegalComponentStateException e) {
                        return; // might happen on window creation
                }
        }


        /** fetch suggestions from SuggestionProvider
         *
         *
         *
         */
        private class SuggestionFetcher extends SwingWorker<String, Object> {
                /** flag used to stop the thread */
                private AtomicBoolean stop = new AtomicBoolean(false);

                String previousWord;
                /**
                 * Standard run method used in threads
                 * responsible for the actual search
                 */
                @Override
                public String doInBackground() {
                        try {
                                setFont(busy);
                                String userInput = getText().trim();
                                if ( userInput == null || userInput.equals(""))
                                        return "";

                                if ( previousWord != null){
                                        if ( userInput.equals(previousWord))
                                                return "";
                                }
                                previousWord = userInput;

                                suggestions = autoSuggestProvider.getSuggestion(userInput);

                                setFont(regular);

                                if (suggestions.size() > 0) {
                                        list.setListData(suggestions);
                                        list.setSelectedIndex(0);
                                        list.ensureIndexIsVisible(0);
                                        dialog.setVisible(true);
                                } else {
                                        dialog.setVisible(false);
                                }
                        } catch (Exception e) {
                                //e.printStackTrace();
                                // ignore...

                        }
                        return "Done.";
                }

                public void setStop(){
                        stop.set(true);
                }


        }
}