/*

 * Copyright (c) 1998, 2006, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package javax.swing.text.html;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import java.net.MalformedURLException;

import java.net.URL;

import javax.swing.text.*;

import javax.swing.*;

import javax.swing.border.*;

import javax.swing.event.*;

import java.util.*;

/**

 * HiddenTagView subclasses EditableView to contain a JTextField showing

 * the element name. When the textfield is edited the element name is

 * reset. As this inherits from EditableView if the JTextComponent is

 * not editable, the textfield will not be visible.

 *

 * @author  Scott Violet

 */

class HiddenTagView extends EditableView implements DocumentListener {

    HiddenTagView(Element e) {

        super(e);

        yAlign = 1;

    }

    protected Component createComponent() {

        JTextField tf = new JTextField(getElement().getName());

        Document doc = getDocument();

        Font font;

        if (doc instanceof StyledDocument) {

            font = ((StyledDocument)doc).getFont(getAttributes());

            tf.setFont(font);

        }

        else {

            font = tf.getFont();

        }

        tf.getDocument().addDocumentListener(this);

        updateYAlign(font);

        // Create a panel to wrap the textfield so that the textfields

        // laf border shows through.

        JPanel panel = new JPanel(new BorderLayout());

        panel.setBackground(null);

        if (isEndTag()) {

            panel.setBorder(EndBorder);

        }

        else {

            panel.setBorder(StartBorder);

        }

        panel.add(tf);

        return panel;

    }

    public float getAlignment(int axis) {

        if (axis == View.Y_AXIS) {

            return yAlign;

        }

        return 0.5f;

    }

    public float getMinimumSpan(int axis) {

        if (axis == View.X_AXIS && isVisible()) {

            // Default to preferred.

            return Math.max(30, super.getPreferredSpan(axis));

        }

        return super.getMinimumSpan(axis);

    }

    public float getPreferredSpan(int axis) {

        if (axis == View.X_AXIS && isVisible()) {

            return Math.max(30, super.getPreferredSpan(axis));

        }

        return super.getPreferredSpan(axis);

    }

    public float getMaximumSpan(int axis) {

        if (axis == View.X_AXIS && isVisible()) {

            // Default to preferred.

            return Math.max(30, super.getMaximumSpan(axis));

        }

        return super.getMaximumSpan(axis);

    }

    // DocumentListener methods

    public void insertUpdate(DocumentEvent e) {

        updateModelFromText();

    }

    public void removeUpdate(DocumentEvent e) {

        updateModelFromText();

    }

    public void changedUpdate(DocumentEvent e) {

        updateModelFromText();

    }

    // View method

    public void changedUpdate(DocumentEvent e, Shape a, ViewFactory f) {

        if (!isSettingAttributes) {

            setTextFromModel();

        }

    }

    // local methods

    void updateYAlign(Font font) {

        Container c = getContainer();

        FontMetrics fm = (c != null) ? c.getFontMetrics(font) :

            Toolkit.getDefaultToolkit().getFontMetrics(font);

        float h = fm.getHeight();

        float d = fm.getDescent();

        yAlign = (h > 0) ? (h - d) / h : 0;

    }

    void resetBorder() {

        Component comp = getComponent();

        if (comp != null) {

            if (isEndTag()) {

                ((JPanel)comp).setBorder(EndBorder);

            }

            else {

                ((JPanel)comp).setBorder(StartBorder);

            }

        }

    }

    /**

     * This resets the text on the text component we created to match

     * that of the AttributeSet for the Element we represent.

     * <p>If this is invoked on the event dispatching thread, this

     * directly invokes <code>_setTextFromModel</code>, otherwise

     * <code>SwingUtilities.invokeLater</code> is used to schedule execution

     * of <code>_setTextFromModel</code>.

     */

    void setTextFromModel() {

        if (SwingUtilities.isEventDispatchThread()) {

            _setTextFromModel();

        }

        else {

            SwingUtilities.invokeLater(new Runnable() {

                public void run() {

                    _setTextFromModel();

                }

            });

        }

    }

    /**

     * This resets the text on the text component we created to match

     * that of the AttributeSet for the Element we represent.

     */

    void _setTextFromModel() {

        Document doc = getDocument();

        try {

            isSettingAttributes = true;

            if (doc instanceof AbstractDocument) {

                ((AbstractDocument)doc).readLock();

            }

            JTextComponent text = getTextComponent();

            if (text != null) {

                text.setText(getRepresentedText());

                resetBorder();

                Container host = getContainer();

                if (host != null) {

                    preferenceChanged(this, true, true);

                    host.repaint();

                }

            }

        }

        finally {

            isSettingAttributes = false;

            if (doc instanceof AbstractDocument) {

                ((AbstractDocument)doc).readUnlock();

            }

        }

    }

    /**

     * This copies the text from the text component we've created

     * to the Element's AttributeSet we represent.

     * <p>If this is invoked on the event dispatching thread, this

     * directly invokes <code>_updateModelFromText</code>, otherwise

     * <code>SwingUtilities.invokeLater</code> is used to schedule execution

     * of <code>_updateModelFromText</code>.

     */

    void updateModelFromText() {

        if (!isSettingAttributes) {

            if (SwingUtilities.isEventDispatchThread()) {

                _updateModelFromText();

            }

            else {

                SwingUtilities.invokeLater(new Runnable() {

                    public void run() {

                        _updateModelFromText();

                    }

                });

            }

        }

    }

    /**

     * This copies the text from the text component we've created

     * to the Element's AttributeSet we represent.

     */

    void _updateModelFromText() {

        Document doc = getDocument();

        Object name = getElement().getAttributes().getAttribute

            (StyleConstants.NameAttribute);

        if ((name instanceof HTML.UnknownTag) &&

            (doc instanceof StyledDocument)) {

            SimpleAttributeSet sas = new SimpleAttributeSet();

            JTextComponent textComponent = getTextComponent();

            if (textComponent != null) {

                String text = textComponent.getText();

                isSettingAttributes = true;

                try {

                    sas.addAttribute(StyleConstants.NameAttribute,

                                     new HTML.UnknownTag(text));

                    ((StyledDocument)doc).setCharacterAttributes

                        (getStartOffset(), getEndOffset() -

                         getStartOffset(), sas, false);

                }

                finally {

                    isSettingAttributes = false;

                }

            }

        }

    }

    JTextComponent getTextComponent() {

        Component comp = getComponent();

        return (comp == null) ? null : (JTextComponent)((Container)comp).

                                       getComponent(0);

    }

    String getRepresentedText() {

        String retValue = getElement().getName();

        return (retValue == null) ? "" : retValue;

    }

    boolean isEndTag() {

        AttributeSet as = getElement().getAttributes();

        if (as != null) {

            Object end = as.getAttribute(HTML.Attribute.ENDTAG);

            if (end != null && (end instanceof String) &&

                ((String)end).equals("true")) {

                return true;

            }

        }

        return false;

    }

    /** Alignment along the y axis, based on the font of the textfield. */

    float yAlign;

    /** Set to true when setting attributes. */

    boolean isSettingAttributes;

    // Following are for Borders that used for Unknown tags and comments.

    //

    // Border defines

    static final int circleR = 3;

    static final int circleD = circleR * 2;

    static final int tagSize = 6;

    static final int padding = 3;

    static final Color UnknownTagBorderColor = Color.black;

    static final Border StartBorder = new StartTagBorder();

    static final Border EndBorder = new EndTagBorder();

    static class StartTagBorder implements Border, Serializable {

        public void paintBorder(Component c, Graphics g, int x, int y,

                                int width, int height) {

            g.setColor(UnknownTagBorderColor);

            x += padding;

            width -= (padding * 2);

            g.drawLine(x, y + circleR,

                       x, y + height - circleR);

            g.drawArc(x, y + height - circleD - 1,

                      circleD, circleD, 180, 90);

            g.drawArc(x, y, circleD, circleD, 90, 90);

            g.drawLine(x + circleR, y, x + width - tagSize, y);

            g.drawLine(x + circleR, y + height - 1,

                       x + width - tagSize, y + height - 1);

            g.drawLine(x + width - tagSize, y,

                       x + width - 1, y + height / 2);

            g.drawLine(x + width - tagSize, y + height,

                       x + width - 1, y + height / 2);

        }

        public Insets getBorderInsets(Component c) {

            return new Insets(2, 2 + padding, 2, tagSize + 2 + padding);

        }

        public boolean isBorderOpaque() {

            return false;

        }

    } // End of class HiddenTagView.StartTagBorder

    static class EndTagBorder implements Border, Serializable {

        public void paintBorder(Component c, Graphics g, int x, int y,

                                int width, int height) {

            g.setColor(UnknownTagBorderColor);

            x += padding;

            width -= (padding * 2);

            g.drawLine(x + width - 1, y + circleR,

                       x + width - 1, y + height - circleR);

            g.drawArc(x + width - circleD - 1, y + height - circleD - 1,

                      circleD, circleD, 270, 90);

            g.drawArc(x + width - circleD - 1, y, circleD, circleD, 0, 90);

            g.drawLine(x + tagSize, y, x + width - circleR, y);

            g.drawLine(x + tagSize, y + height - 1,

                       x + width - circleR, y + height - 1);

            g.drawLine(x + tagSize, y,

                       x, y + height / 2);

            g.drawLine(x + tagSize, y + height,

                       x, y + height / 2);

        }

        public Insets getBorderInsets(Component c) {

            return new Insets(2, tagSize + 2 + padding, 2, 2 + padding);

        }

        public boolean isBorderOpaque() {

            return false;

        }

    } // End of class HiddenTagView.EndTagBorder

} // End of HiddenTagView