/*
 *                 Sun Public License Notice
 *
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 *
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.xml.text.syntax.dom;

import java.util.*;
import javax.swing.text.BadLocationException;

import org.w3c.dom.*;
import org.netbeans.modules.xml.text.syntax.*;
import org.netbeans.modules.xml.spi.dom.*;
import org.netbeans.editor.*;

/**
 * Represents tag syntax element. It also represent DOM Element.
 * This duality means that one document element is represented by
 * two DOM Element instances - one for start tag and one for
 * end tag. This is hidden during document traversal but never relay on
 * equals. The equals is used for syntax element
 * purposes.
 */
public abstract class Tag extends SyntaxNode implements Element, XMLTokenIDs {
    
    protected NamedNodeMap domAttributes;
    
    protected String name;
    
    public Tag(XMLSyntaxSupport support, TokenItem from, int to, String name, Collection attribs) {
        super( support, from,to );
        this.name = name;
    }
    
    public final short getNodeType() {
        return Node.ELEMENT_NODE;
    }
    
    public final String getNodeName() {
        return getTagName();
    }
    
    public final String getTagName() {
        return name;
    }
    
    /**
     * Create properly bound attributes and cache results.
     * Parse attributes from first token.
     */
    public synchronized NamedNodeMap getAttributes() {
        
        // cached results not implemented
        if (domAttributes != null) return domAttributes;
        
        Map map = new HashMap(3);
        
        SCAN_LOOP:
            for (TokenItem next = first.getNext(); next != null; next = next.getNext()) {
                TokenID id = next.getTokenID();
                String name;
                String value;
                if (id == ARGUMENT) {
                    TokenItem attributeStart = next;
                    name = next.getImage();
                    while (next.getTokenID() != VALUE) {
                        next = next.getNext();
                        if (next == null) break SCAN_LOOP;
                    }
                    
                    // fuzziness to relax minor tokenization changes
                    String image = next.getImage();
                    char test = image.charAt(0);
                    if (image.length() == 1) {
                        if (test == '"' || test == '\'') {
                            next = next.getNext();
                        }
                    }
                    
                    if (next == null) break SCAN_LOOP;
                    value = next.getImage();
                    
                    Object key = NamedNodeMapImpl.createKey(name);
                    map.put(key, new AttrImpl(support, attributeStart, this));
                    
                    next = Util.skipAttributeValue(next, test);
                    if (next == null) break SCAN_LOOP;
                } else if (id == WS) {
                    // just skip
                } else {
                    break; // end of element markup
                }
            }
            
            // domAttributes = new NamedNodeMapImpl(map);
            return new NamedNodeMapImpl(map);
    }
    
    public String getAttribute(String name) {
        Attr attribute = getAttributeNode(name);
        if (attribute == null) return null;
        return attribute.getValue();
    }
    
    public final void setAttribute(String name, String value) {
        NamedNodeMap attributes = getAttributes();
        Node attr = attributes.getNamedItem(name);
        if (attr != null) {
            attr.setNodeValue(value);
        } else {
            String stringToInsert = " " + name + "=" + '"' + value + '"';
            
            // Get the document and lock it
            BaseDocument doc = (BaseDocument)support.getDocument();
            doc.atomicLock();
            
            // An attribute with the name was not found for the element
            // Let's add it to the end
            int insertStart = offset + length - 1;
            
            SCAN_LOOP:
                for (TokenItem next = first.getNext(); next != null; next = next.getNext()) {
                    TokenID id = next.getTokenID();
                    if (id == ARGUMENT) {
                        while (next.getTokenID() != VALUE) {
                            next = next.getNext();
                            if (next == null) break SCAN_LOOP;
                        }
                        
                        if (next == null) break SCAN_LOOP;
                        
                        String image = next.getImage();
                        char test = image.charAt(0);
                        
                        while (next.getTokenID() == VALUE || next.getTokenID() == CHARACTER) {
                            String actualValue = Util.actualAttributeValue(image);
                            if (!actualValue.equals(image)) {
                                insertStart = next.getOffset() + actualValue.length();
                                break SCAN_LOOP;
                            }
                            next = next.getNext();
                            if (next == null) break SCAN_LOOP;
                            
                            // Check if this is the last token in the element and set the
                            // insertStart if it is
                            image = next.getImage();
                            insertStart = next.getOffset();
                            if (image.length() > 0 && image.charAt(image.length() - 1) == '>') {
                                // The element is closing
                                insertStart += image.length() - 1;
                                if (image.length() > 1 && image.charAt(image.length() - 2) == '/') {
                                    // We have a closed element at the form 
                                    insertStart--;
                                }
                            }
                        }
                        
                        if (next == null) break SCAN_LOOP;
                    } else if (id == WS) {
                        // just skip
                    } else {
                        break; // end of element markup
                    }
                }
                
                // Update the document
                try {
                    doc.insertString(insertStart, stringToInsert, null);
                    doc.invalidateSyntaxMarks();
                } catch( BadLocationException e ) {
                    throw new DOMException(DOMException.INVALID_STATE_ERR , e.getMessage());
                } finally {
                    doc.atomicUnlock();
                }
        }
        
        // Update this object's member variables
        retokenizeObject();
    }
    
    public final void removeAttribute(String name) {
        throw new ROException();
    }
    
    public Attr getAttributeNode(String name) {
        NamedNodeMap map = getAttributes();
        Node node = map.getNamedItem(name);
        return (Attr) node;
    }
    
    public final Attr setAttributeNode(Attr attribute) {
        throw new ROException();
    }
    
    public final Attr removeAttributeNode(Attr attribute) {
        throw new ROException();
    }
    
    public NodeList getElementsByTagName(String name) {
        throw new ROException();
    }
    
    /**
     * Returns previous sibling by locating pairing start tag
     * and asking it for previous non-start tag SyntaxNode.
     */
    public Node getPreviousSibling() {
        SyntaxNode prev = getStartTag();
        if (prev == null) return null;
        prev = findPrevious(prev);
        if (prev instanceof StartTag) {
            return null;
        } else {
            return prev;
        }
    }
    
    /**
     * Returns next sibling by locating pairing end tag
     * and asking it for next non-end tag SyntaxNode.
     */
    public Node getNextSibling() {
        SyntaxNode next = getEndTag();
        if (next == null) return null;
        next = findNext(next);
        if (next instanceof EndTag) {
            return null;
        } else {
            return next;
        }
    }
    
    public Node getFirstChild() {
        NodeList list = getChildNodes();
        if (list.getLength() == 0) return null;
        return getChildNodes().item(0);
    }
    
    public Node getLastChild() {
        NodeList list = getChildNodes();
        if (list.getLength() == 0) return null;
        return list.item(list.getLength());
    }
    
    protected abstract Tag getStartTag();
    
    protected abstract Tag getEndTag();
    
    //    public boolean equals(Object obj) {
    //        if ((obj instanceof Tag) == false) return false;
    //        return false;
    //    }
    
    
    // unsupported DOM level 2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    public String getAttributeNS(String namespaceURI, String localName) {
        throw new UOException();
    }
    
    public void setAttributeNS(String namespaceURI, String qualifiedName, String value) {
        throw new UOException();
    }
    
    public void removeAttributeNS(String namespaceURI, String localName) {
        throw new UOException();
    }
    
    public Attr getAttributeNodeNS(String namespaceURI, String localName) {
        throw new UOException();
    }
    
    public Attr setAttributeNodeNS(Attr newAttr) {
        throw new UOException();
    }
    
    public NodeList getElementsByTagNameNS(String namespaceURI, String localName) {
        throw new UOException();
    }
    
    public boolean hasAttribute(String name) {
        throw new UOException();
    }
    
    public boolean hasAttributeNS(String namespaceURI, String localName) {
        throw new UOException();
    }
    
    public void retokenizeObject() {
        // Update this object's member variables
        try {
            first = support.getTokenChain(offset, support.getDocument().getLength());
        } catch (BadLocationException e) {
            throw new DOMException(DOMException.INVALID_STATE_ERR , e.getMessage());
        }
    }

    /**
     * We guarantee DOM Node equality by using Java Object's equals.
     * It's potentionally dangerous as it mixes StartTags and EndTags.
     * Never put this object into vector of so until you assumes DOM Node
     * equality.
     * 

     * I would appreciate a methos at DOM that would define
     * Node equals not Objevt's equals.
     */
    public final boolean equals(Object obj) {
        if (obj == this) return true;
        if (obj instanceof Tag) {
            Tag tag = (Tag) obj;
            Tag t1 = tag.getStartTag();
            Tag t2 = getStartTag();
            if (t1 == null || t2 == null) return false;
            return t1.superEquals(t2);
        }
        return false;
    }

    private boolean superEquals(Tag tag) {
        return super.equals(tag);
    }

    /**
     * The same as for equals it's DOM node hashcode.
     */
    public final int hashCode() {
        Tag tag = getStartTag();
        if (tag == null || tag == this) {
            return super.hashCode();
        } else {
            return tag.hashCode();
        }
    }
}