/*
 * Copyright (C) 2006-2007 Sun Microsystems, Inc. All rights reserved. Use is
 * subject to license terms.
 */

package org.jdesktop.swingbinding.adapters;

import java.beans.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.event.*;
import javax.swing.text.*;
import org.jdesktop.beansbinding.ext.BeanAdapterProvider;

/**
 * @author Shannon Hickey
 */
public final class JTextComponentAdapterProvider implements BeanAdapterProvider {

    private static final String PROPERTY_BASE = "text";
    private static final String ON_ACTION_OR_FOCUS_LOST = PROPERTY_BASE + "_ON_ACTION_OR_FOCUS_LOST";
    private static final String ON_FOCUS_LOST = PROPERTY_BASE + "_ON_FOCUS_LOST";

    public final class Adapter extends BeanAdapterBase {
        private JTextComponent component;
        private Document document;
        private boolean inDocumentListener;
        private boolean installedFilter;
        private String cachedText;
        private Handler handler;

        private Adapter(JTextComponent component, String property) {
            super(property);
            this.component = component;
        }

        public String getText() {
            return component.getText();
        }

        public String getText_ON_ACTION_OR_FOCUS_LOST() {
            return getText();
        }

        public String getText_ON_FOCUS_LOST() {
            return getText();
        }

        public void setText(String text) {
            component.setText(text);
            component.setCaretPosition(0);
            cachedText = text;
        }

        public void setText_ON_ACTION_OR_FOCUS_LOST(String text) {
            setText(text);
        }

        public void setText_ON_FOCUS_LOST(String text) {
            setText(text);
        }
        
        protected void listeningStarted() {
            cachedText = component.getText();
            handler = new Handler();
            component.addPropertyChangeListener("document", handler);

            if (property != PROPERTY_BASE) {
                component.addFocusListener(handler);
            }

            if (property == ON_ACTION_OR_FOCUS_LOST && component instanceof JTextField) {
                ((JTextField)component).addActionListener(handler);
            }

            document = component.getDocument();
            installDocumentListener();
            
        }
        
        protected void listeningStopped() {
            cachedText = null;
            component.removePropertyChangeListener("document", handler);
            
            if (property != PROPERTY_BASE) {
                component.removeFocusListener(handler);
            }
            
            if (property == ON_ACTION_OR_FOCUS_LOST && (component instanceof JTextField)) {
                ((JTextField)component).removeActionListener(handler);
            }

            uninstallDocumentListener();
            document = null;
            handler = null;
        }

        private void installDocumentListener() {
            if (property != PROPERTY_BASE) {
                return;
            }

            boolean useDocumentFilter = !(component instanceof JFormattedTextField);
            
            if (useDocumentFilter && (document instanceof AbstractDocument) &&
                    ((AbstractDocument)document).getDocumentFilter() == null) {
                ((AbstractDocument)document).setDocumentFilter(handler);
                installedFilter = true;
            } else {
                document.addDocumentListener(handler);
                installedFilter = false;
            }
        }
        
        private void uninstallDocumentListener() {
            if (property != PROPERTY_BASE) {
                return;
            }

            if (installedFilter) {
                AbstractDocument ad = (AbstractDocument)document;
                if (ad.getDocumentFilter() == handler) {
                    ad.setDocumentFilter(null);
                }
            } else {
                document.removeDocumentListener(handler);
            }
        }

        private class Handler extends DocumentFilter implements ActionListener, DocumentListener,
                FocusListener, PropertyChangeListener {

            private void updateText() {
                Object oldText = cachedText;
                cachedText = getText();
                firePropertyChange(oldText, cachedText);
            }

            private void documentTextChanged() {
                try {
                    inDocumentListener = true;
                    textChanged();
                } finally {
                    inDocumentListener = false;
                }
            }
            
            private void textChanged() {
                updateText();
            }
            
            public void propertyChange(PropertyChangeEvent pce) {
                uninstallDocumentListener();
                document = component.getDocument();
                installDocumentListener();
                updateText();
            }
            
            public void actionPerformed(ActionEvent e) {
                updateText();
            }

            public void focusLost(FocusEvent e) {
                if (!e.isTemporary()) {
                    updateText();
                }
            }
            
            public void insertUpdate(DocumentEvent e) {
                documentTextChanged();
            }
            
            public void removeUpdate(DocumentEvent e) {
                documentTextChanged();
            }
            
            public void replace(DocumentFilter.FilterBypass fb, int offset,
                    int length, String text, AttributeSet attrs)
                    throws BadLocationException {
                
                super.replace(fb, offset, length, text, attrs);
                textChanged();
            }
            
            public void insertString(DocumentFilter.FilterBypass fb, int offset,
                                     String string, AttributeSet attr) throws BadLocationException {

                super.insertString(fb, offset, string, attr);
                textChanged();
            }
            
            public void remove(DocumentFilter.FilterBypass fb, int offset, int length) throws BadLocationException {
                super.remove(fb, offset, length);
                textChanged();
            }

            public void focusGained(FocusEvent e) {}
            public void changedUpdate(DocumentEvent e) {}
        }
        
    }
    
    public boolean providesAdapter(Class<?> type, String property) {
        if (!JTextComponent.class.isAssignableFrom(type)) {
            return false;
        }

        property = property.intern();

        return property == PROPERTY_BASE ||
               property == ON_ACTION_OR_FOCUS_LOST ||
               property == ON_FOCUS_LOST;
                 
    }
    
    public Object createAdapter(Object source, String property) {
        if (!providesAdapter(source.getClass(), property)) {
            throw new IllegalArgumentException();
        }
        
        return new Adapter((JTextComponent)source, property);
    }
    
    public Class<?> getAdapterClass(Class<?> type) {
        return JTextComponent.class.isAssignableFrom(type) ?
            JTextComponentAdapterProvider.Adapter.class :
            null;
    }
    
}